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Conference vicki::boats

Title:Powerboats
Notice:Introductions 2 /Classifieds 3 / '97 Ski Season 1267
Moderator:KWLITY::SUTER
Created:Thu May 12 1988
Last Modified:Wed Jun 04 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:1275
Total number of notes:18109

703.0. "AUTO ENGINE MARINE CONVERSIONS???" by POBOX::SWENSON () Wed Jul 04 1990 11:43

    Does anyone make conversion kits to turn an auto engine into a marine
    engine?  About twenty years ago I had a catalog of this kind of
    hardware.  About twenty years ago I didn't have a boat!
T.RTitleUserPersonal
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703.1OSCO- Sauderton, PABIZNIS::CADMUSThu Jul 05 1990 12:1154
    
    
    OSCO corp in sauderton PA(the peple that make the manifolds) offer
    conversion kits.
    
    You need :  (assuming an inboard, not I/O)
    
    . change head gaskets (you need marine gaskets if you are Salt water
    cooled), also intake manifold gasket on a V/8
    
    . Marine(spark arresting) starter and alternator
    
    . mechanical advace only distributor
    
    . wedge block for mounting carb or new intake manifold with built in 
     "wedge" - (marine engines are at quite an angle from the horizontal
    and the carb has to be level)
    
    . Bell housing
    
    . drive plate for transmission shaft
    
    . marine reversee gear and mounts.
    
    . flame arrestor for carb
    
    . marine water circulation pump
    
    . engine mounted raw water pump
    
    . assorted mounts and pulleys for raw water pump and alternator
    
    . water cooled exhaust manifolds
    
    .CG approved fuel pump
    
    . engine mounts
    
    . replace all core plugs with brass core plugs (freeze plugs) if not
    already equipped with brass plugs.
    
    One caution- use a truck block , not automotive- although the
    car/truck engines may have the same displacement, the truck engines are
    a lot beefier as they are designed to handle the higher loads. The car
    enginesd have a nasty habit of disintegrating under the costant high
    loads in marine service.
    
    You might be better off finding a good used set up with a bad engine-
    get all the accessories rebuilt ( starter, carb, alternator, etc)
    and rebuild a truck block.
    
    Another difference is that the marine engines use different cams than
    cars/trucks- especilly the late model smog engines.
    
703.2Engine rotation may be differentSALEM::NORCROSS_WThu Jul 05 1990 13:5815
    You will also need to decide which direction you need the engine
    to rotate.  Many single engine applications rotate opposite of 
    a car's rotation.  Firing order changes as well as the distributor.
    I am slowly rebuilding a 1964 Interceptor Motor which is based on
    a 260 cubic inch Ford block.  As long as you specify "Marine" for
    such things as starter, alternator, and carb. you can generally
    order them at a reasonable price at auto parts stores although I
    did have to send my carb to Michigan to a "Coast Guard Authorized"
    carb rebuilding shop which specialized in obsolete carbs.  I probably
    should have converted to a Holly marine carb but I'm trying to stay
    original.  I do not have a "wedge" plate on my motor but maybe the
    carb was designed for angled installation.  Make sure that anything
    having to do with the electrical system or fuel system is Coast
    Guard approved or you take the chance of having an explosion.
    Wayne
703.3Rev Rot. not a problem in single screwBIZNIS::CADMUSMon Jul 09 1990 11:0827
    
    
     Most modern inboards and I/O's drive off the flywheel end which gives 
    CCW rotation. This is standard rotation for single screw boats. Some of
    the older marine engines based on automotive blocks drove off the
    timing case and and engine rotation was reversed from the automotive.
    My old Kermath (based on 4 cyl Jeep/Continental engine) was that way-
    
     Distributor and camshaft are different (and expensive) on engine that
    have reverse rotation- sometimes oil pump has to be changed also as it
    drives off the camshaft in many engines.
    
     Don't worry about the reverse rotation if you have single screw- the
    standard rotation is CCW (looking at the flywheel)  for both automotive
    and marine engines. all the coversion kits I have seen drive from the
    flywheel end.OMC, Crusader, Mercruiser use CCW (standard automotive)
    rotation on their inboards and I/o's for single screw.
    
    Check with OSCO- also I just got a new catalog in the mail- great  has
    gaskets, water pumps, ignition systems, manifolds, starters,
    alternators  etc.- none of the clothes and schlock you find in the
    other catalogs- looks like it's geared to boatbuilders and commercial
    boating.
    
    National Marine Supply Corp
    800-645-2565 
    
703.4CCW - Are you sure?DNEAST::OKERHOLM_PAUMon Jul 09 1990 13:5612
    Re .3> 
    	I'll be the first to admit my memory ain't worth much but I'm 
    pretty sure that the props on most single screw boats rotate CW (looking 
    at them from the stern). I think this is standard for all outboards, 
    inboards and I/O's. 
    	I realize reply .3 stated engine rotation vs prop rotation so maybe
    there is no disconnect. Is that the case? Does the rotation go through
    a reversal between the flywheel and the prop? Or is the explanation of
    the reference point causing my confusion? Or do we disagree on which way 
    the world goes around? :^)
    
    Paul    
703.5CW/Righted handed propsLEVERS::SWEETMon Jul 09 1990 15:544
    I agree with Paul, right handed prop's are the norm. This is also
    why most single screw boats will not back to the port.
    
    Bruce
703.6Maybe that's what "reverse gear" does?SALEM::NORCROSS_WMon Jul 09 1990 15:577
    Paul, we are both confused.  Could have something to do with the
    tranny being called a "reverse gear" in alot of the literature
    I've received (see note 690).  A "reverse gear" tranny could be
    reversing the direction of rotation by the time the prop is
    turned.  I'm dealing with something from the mid-sixties that just
    is very different from what is available today.
    Wayne
703.7Reversing is in the gearing!BIZNIS::CADMUSMon Jul 09 1990 17:2546
    
    
    re:.4
    
    Paul: There is a reversal- in the outdrive on the I/O's , the V drive
    , or the reduction gears. I'm not certain wether the 1:1 reverse gears
    reverse direction also. Almost all of the lobster boats in Maine use
    Chevvy or olds engines driven from the flywheel end with a marine
    reverse gear (reverse gear comes from the old days when a transmission
    , if used would have forward/neutral. The early engines were 2 stroke,
    so reversing was accomplished by running the engine backwards, ala 
    a modern golf cart)
    
    
     If I recall, the last time I looked at the OSCO catalog for conversin
    kits, tou could specify LH rotation, RH rotation, ratio, and wether the
    input/output roattion was the same or opposite  for the
    tranmissions/reverse gears.
    
     The I/O's handle dual engines by having one I/O in reverse with a LH
    prop and the other in forward with a RH prop, and both engines CCW
    rotation from the flywheel end.
    
     The bottom line is that it is a lot cheaper to mess around with gears
    and clutches than major engine components or the drive manufacturers.
    
    
     I've also seen setups where both engines are the same roattion, in a
    twin screw set up, with one driving from the flywheel wide and one from
    the timing case side- sure looked funny!
    
     The conversions use a std automotive bell housing and flywheel- a
    drive plate is bolted to the flywheel instead of the clutch components
    and the transmission bolts right up to the bell housing.
    
     I have a friend on the west coast who has an older 38' Chris Craft-
    engines were 460 CI (lincoln Blocks) and tired- he replaced both with 
    standard rotation Chevy 350 conversions- gained better performance and
    improved economy (he claims because of the weight loss- those old
    Chris's weighed a ton!) 
                           
    
    
     
    
    
703.8GET AN OSCO CATALOG?POBOX::SWENSONFri Jul 13 1990 01:082
    How do I go about getting an OSCO catalog?  Got an address and phone
    number?
703.9ward...HYEND::J_BORZUMATOFri Jul 13 1990 10:444
    Ward Maring in Winthrop Ma. sells their products. they may be able
    to give you OSCO's phone # etc...
    
    Jim.
703.10HERE'S OSCO INFOBIZNIS::CADMUSFri Jul 13 1990 11:055
      OSCO MARINE CORP
      PO BOX 136
      SOUDERTON, PA
      (215) 855-8268
    
703.11My engine and prop turn clockwiseSALEM::NORCROSS_WTue Jul 17 1990 09:1020
    I just had to check my boat's engine rotation this morning.  (Note:
    this is an old 1965 Century inboard with an Interceptor Ford small
    block V-8).  The engine and prop both turn in a clockwise (right
    hand) direction which leads me to believe that at  least the 1:1
    direct drive inboard trannys do not reverse the direction of rotation.
    (Note: rotation viewed from back of boat)
    The Mallory distributor designates if the engine is a left hand
    (distributor "model A") or a right hand (distributor "model B").
    The literature which I received from Warner Marine tranny (see note
    690) states that their transmission (with a few exceptions) will
    rotate in either direction if the pump is properly indexed.  There
    were a couple of trannys listed (both reduction models) which actually
    reversed the direction of rotation.  The others required a right
    hand prop for clockwise rotation and a left hand prop for
    counter-clockwise rotation. If you are going to convert an engine
    for inboard use, may I suggest that you call Boyd Jackson at Marine
    Gear (Rowley, Ma.) to get the right set-up.  He's been very helpful
    to me.  If you're doing an I/O and the I/O reverses the direction
    of rotation internally, then you can you a standard (counter clockwise
    rotating) engine without a problem.
703.12Trailer Boat Mag. has letters on engine conv.SALEM::NORCROSS_WTue Jul 24 1990 10:5410
    This month's Trailer Boat magazine has a couple of good letters
    responding to a letter in last month's edition from a reader who
    wanted to convert a 400 cu. in Chevy to marine use.  The responses
    to that letter are very interesting.  They give a good idea of
    what to choose as a base engine (short stroke for low end torque
    and reliabilty, strong lower end to sustain high RPM's for continued
    periods of time, etc.)  You may want to read the letters before
    you choose an engine to convert.  (I wouldn't use a 400 cu. in.
    Chevy after reading the letters!)
    Wayne
703.13marine-quality spark plugsMIZZEN::DEMERSTue Apr 20 1993 13:047
sorta related topic - couldn't find a better fit...

I understand what makes some components "marine-quality".  What is done to
spark plugs for marine applications?


/Chris
703.14I only put my boat in marine quality waterAPACHE::URBANTue Apr 20 1993 14:436
    >>> What is done to spark plugs for marine applications?                       
    
    I suspect the price is doubled at mail order houses and tripled at
    marinas.
    
    ;>)
703.15oh yeh""""""""""""FDCV07::BORZUMATOTue Apr 20 1993 17:045
    
    The catalogs and marinas sell "designer plugs"
    
    
    The difference is none.
703.16No differences, in "most" casesGOLF::WILSONThink Spring!Wed Apr 21 1993 13:3623
    In general, there's nothing different about a marine plug except
    that it's heat range is geared to the intended use.  But that
    makes it no different from automotive plugs, which also have their 
    own specific heat ranges.
    
    I suspect the major difference in marine plugs *is* that most
    people buy them from marinas, at 2X or 3X the regular price. 
    If you can buy them somewhere else, you'll find that prices are
    much more in line with automotive plugs.  I buy Champion J4C,
    J6C, and J8C marine plugs at WalMart for something like $1.47 
    each.  I think they carry some of the other popular marine
    plugs also.  
    
    There is at least one exception to the "no difference" rule
    however.  Champion has a line of plugs that is supposedly
    treated or plated in some way for the marine environment.  They
    cost about 5 bucks a piece, and use the standard numbering 
    system, with a "Q" in front, i.e. Q-L77JC4.  They seem to work 
    well, I got 3 *full* seasons of use out of the set I had in my 
    88hp Johnson V-4.  Maybe a set of standard plugs would have 
    worked as well, I don't know.  
    
    Rick
703.17Big Block marine conversionKAHALA::SUTERNever too Hot!Thu Jun 24 1993 13:5945
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Note 1068.0              Big Block marine conversion....              No replies
HURON::VALLIERE                                      36 lines  24-JUN-1993 12:55
--------------------------------------------------------------------------------


	I am hoping someone can answer my questions.... (I read note 703)

	I currenly have a 1987 454 Magnum running 330 HP. There was 
	extensive corrosion damage to the due to a cracked exhaust 
	manifold. I am looking for the least expensive way to replace 
	the motor.

	I found a 454 motor that came out of a Corvette that has been recently
	machined and still disassembled - new piston, rings rods, etc.- for
	about $1000.  Before purchasing it I want to be	certain that the motor 
	will perform properly for a marine application.

	This motor is a 2 bolt main, cast crank, .030 bore and running 11:1 
	compression.  It is basically setup up as a stock Corvette motor - 
	nothing radical... The main difference between the 2 motors that I 
	noticed is that the head and intake manifolds are setup with oval 
	ports. My existing motor has square ports. 

	** What are the performance considerations and tradeoffs? is it my
	understanding that the oval port produce more low end torque...

	** At the time I write this, I am uncertain whether my present motor
	is a 2 bolt or 4 bolt main? - Will a 2 bolt main handle the loads?

	My plan is to strip the timing chain assembly (double roller chain)
	and cams from my old motor. Get marine gaskets, bronze freeze plugs and
	purchase new exhaust manifolds and risers.

	The outdrive is rated sufficiently to handle 400+ HP. Any other
	considerations that I should keep in mind.

	Thanks, Ed
	

703.18Look closely...KAHALA::SUTERNever too Hot!Thu Jun 24 1993 14:0720
    
    Ed,
    
    	Just a few thoughts...
    
    	Are manifolds for the oval exhaust ports available?
    
    	I'd guess that 2 bolt mains would be fine...
    
    	Don't forget to swap the starter also as it's "ignition protected".
    
    	The carb is probably "marine" on your current engine.
    
    	How about rotation? same?
    
    	I'd be a little leary of a "DIS-ASSEMBLED" motor. I'd feel
    much better about buying one I can listen to.... BTW: I understand
    that a complete new marine engine is about 3-4k...
    
    Rick
703.19remanufactured and guaranteed!KAHALA::SUTERNever too Hot!Thu Jun 24 1993 14:098
    
    Oh yeah...
    
    	And a small block chevy shortblock from Targetmaster can be
    found for about 600 bucks... Big blocks must be available also
    one would think...
    
    Rick
703.20how about a new oneUSCTR1::BORZUMATOThu Jun 24 1993 14:5910
    
    I know a short block 350 chevy can be had for about 1300-1400
    
    American...  New in the box, why screw around with this corvette
    
    engine in peices....  plus you'll have a warranty, and a new 
    
    block ready for marine use...
    
    JIm.
703.21what about truck version?SALEM::LAYTONThu Jun 24 1993 15:595
    How about a truck version of that 454?  Would it's price fall somewhere
    between auto and marine?  Like 4 bolt mains, but not bronze freeze
    plugs?
    
    Carl
703.22FWIWSALEM::LAYTONThu Jun 24 1993 16:037
    Oh, yeah, I remember reading in a boat mag about some speed boat or
    other that they (Chevrolet) put a Corvette motor into as a publicity
    stunt.  There were no plans by the boat mfgr to make that motor an 
    option, since the marine version would be quite a bit more durable 
    over the long haul.  
    
    Carl
703.23Go for it!SALEM::NORCROSS_WFri Jun 25 1993 10:2727
    Actually, this sounds like alot of fun.  First, if the noter is used to
    running with a 454, then they are not going to be happy going down to a
    350, plus the expense of buying some of the parts that don't come with
    a Target master 350 engine (marine bellhousing, motor and tranny mounts,
    etc) will make up the difference in cost anyways.  Personally, I would
    rather have the engine apart to check it out prior to buying it.  Just
    because someone claims to have rebuilt the engine, they may have done a
    poor or incomplete job or used inferior bolts, etc.  By having it
    apart, you can still check it to make sure it's been properly machined
    before it's put back together.  I would then take the pieces to someone
    who will take the time to properly re-assemble it using high grade
    fastners and internal components.
    
    On the 454, I may be wrong cause I'm no Chevy expert, but I don't
    believe that the 454 ever came in a 4 bolt version, just the 350. 
    There are machine shops/engine builders that can modify a 2 bolt engine
    to 4 bolt for racing purposes, but the Chev 454 normally doesn't need
    it.  Also, oval ports will generally produce less horsepower but a good
    engine builder, while putting your engine back together, could clean up
    the ports and make a big difference.  Using difference heads will
    require the use of the intake manifold from that engine.  The marine
    carb may not fit.  Besides the starter, you also have to swap over your
    distributor, alternator, water pump, motor mounts, etc.
    If the price of the machined 454 is right, I'ld go for it.  Sounds like
    fun.
    Wayne
    
703.24Trader Magazine has enginesNWD002::SASLOW_STSTEVEFri Jun 25 1993 12:414
    Get a copy of the National Boat Trader. In it, are ads for marine
    engines from places that will ship anywhere at good prices. At least,
    you will have good pricing information.
    
703.25TOOK::SWISTJim Swist LKG2-2/T2 DTN 226-7102Fri Jun 25 1993 14:005
    re: .23  You gain 70 propshaft HP (230 vs 300) going from 5.7L up
    to 7.4L (these are 1993 Merc stats, but yours probably wouldn't be
    much different).  I am told (by someone who went in the opposite
    direction) that the 70HP came at a ridiculous cost in increased fuel
    consumption.   Seems that the big block is disproportionally piggy. 
703.26decision timeHURON::VALLIEREFri Jun 25 1993 14:3724
	Thanks for all the responses. Wayne (note 23) captured my logic.
	The engine is in pieces where everything can be inspected. 
	Secondly, my mechanic has literally built many hundreds of 
	engines (he use to work at GM in the seventies). The motor was
	machined by a reputable machine shop. There is some risk but
	both the mechanic and shop will stand by their work.
	
	I am also replacing the exhaust manifolds and risers and essentially
	stripping my old motor, distributor, carb, etc. for remainder of the
	parts. If it plays out the way I hope, I will essentially have a 
	new motor for about $2200. (thats with the motor, new 
	exhaust manifolds and labor). 

	As a side note,  I am replacing a motor that was 330 HP with a motor
	spec'd at 390+ HP. My boat is a 25 ft Corsair (pretty rare around 
	here), and its top speed was 65 MPH. With an additional 60 HP, it
	should be interesting.... the options for this boat was a single
	big block or twin 350's. The high performance twins were spec'd out 
	for a top speed about 75.

	I have pretty much made the decision to go this route (unless the 
	mechanic finds anything wrong when he inspects the motor)- I will let 
	you know how I make out...
703.27The old Big Block vs. Small Block discussion!SALEM::NORCROSS_WMon Jun 28 1993 07:5818
    re:703.25
    
    I would think that gas mileage would be highly dependent on application
    (ie: size of boat) and user habits (are you happy just being on plane
    or is being the fastest boat around important).  You would think that a
    big Harley motorcycle would not get good gas mileage but when allowed
    to poke along, the Japanese multi-valve, multi-cylinder, multi-carb high
    tech screamers don't come close in fuel economy.  Also, the big block
    doesn't even have to break out in a sweat while the small block has to
    work hard constantly.  Unless one wants to install two small blocks in
    place of the one big block which would be a nightmare when it came time
    to make new holes and seal up the old one for the outdrives!
    I'ld take a big block anyday.  I would have to give up the front seat
    in my 15 footer, though!
    One note of caution to the original noter.  You are taking a healthy
    jump in horsepower.  Make sure your drive system can take it.  You may
    want to rebuild it while you are at it.
    Wayne
703.28MKOTS3::RONEYMon Jun 28 1993 12:3915
    Can I give my two cents?
    
    Wayne, threr are versions of 454's that have four bolt mains. I think
    the Mercruiser 454 Magnums are. You are right about the fuel difference
    between the 350 vs. 454. A couple of things to remember. If you are
    using a standard Rochester Quadra-Jet carb, Mercruiser version, the
    secondaries don't kick in til after 3200 rpm. If you have trim tabs you
    can get your boat up on plan quicker and trim out the drive, hold a
    good speed and back off on the throttle to conserve fuel. I've been in
    boats with 454's that will run at 2800-3000rpm and cruise at 30-32mph. 
    That's how you conserve fuel.
    454's are very torquey engines and they will pull better as Wayne has
    mentioned. You have to rev up the 350's to get them to perform. 
    
    Bob 
703.29my 2 cents...USCTR1::BORZUMATOMon Jun 28 1993 15:1827
    
    On milage etc.   I've read a zillion rags over the years.
    
    i like the ones with the boat tests, regardless of the engine
    
    size, or whether its diesel, when they show opitimum cruise
    
    speed/rpm it seems its always around 1 mile per gal.
    
    On the 454 concept, i'm not an expert, my neighbor is,
    
    his thoughts on 454's is that they are pigs. He votes
    
    for the smaller blocks ala 350 etc.   My thoughts are 
    
    that you need to understand the application.
    
    On conserving fuel, the best approach is to go beyond cruising
    
    rpm, lets say cruising is 3200, go to 3500 and pull back
    
    closing the carb, you'll find that you will have the same 
    
    speed, but will be closing the carb instead of opening it.
    
    JIm
    
703.30I agree!SOLVIT::RONEYMon Jun 28 1993 16:2711
    re:29
    
    Jim,
    
    I think we are talking about the same thing. Power up, throttle back
    and cruise! 
    
    The other issue that some folks have not mentioned is the type of hull
    being used. 
    
    Bob
703.31SWAM2::WOYAK_JIMon Jun 28 1993 19:0017
    You might need to re-prop, you can call one of the aftermarket folks
    and they can guide you..I assume you have a newer Bravo..They are good
    to about 550 H.P. so the drive should hold up..These drives have a top
    bearing lubrication problem at very high speeds (upper 80's + ) but
    there are kits/solutions and i do not think you will be in that area.
     I would watch the compression, you mentioned 11:1 which is a tad high
    for dock pump fuel..The bottom end on the big blocks are quite good
    but you might consider having the heads worked as that most likely
    will give you the best bang for the buck.
     As per small block - big block issues raised by a few folks..The
    weakest link in a very high H.P. small block is the drive. The other
    is longivity of the motor..Horse power for horse power "in marine use"
    a big block will outlast a small block and well deliver much more
    torque which is what you need in normal use..
    
    Jim
    
703.32Compression ratio??SUBSYS::CHESTERMon Jun 28 1993 20:4511
    You should check the compression ratio.  Mainly if you are using the
    80+ octane stuff at the marina pump.  In the base note the corvette
    engine was 11:1.  I think Mercruiser used 9:1 and sets the carb rich to
    reduce pinging.  
    
    If you have access to good gas.  go for it.  Sounds like fun.  
    I have a chevy catalog of performance parts and how to info.  Drop me
    line if you you want to borry or copy it.
    
    KC
    
703.33Gas Problems???MKOTS3::RONEYTue Jun 29 1993 10:4710
    If that big block is pushing more than 9.5:1 comp ratio you are going
    to have a gas problem. Some Marina's on Lake Winni are selling premium 
    gas because of the amount of big engines in customer's boats. 
    
    Last week-end I had the opportunity to try out a 25' Checkmate powered
    by a well tuned 454 Magnum and that boat hit 70 without even trying
    hard!!! Boy those big blocks have torque and sure sound great......
    
    
    Bob
703.34SALEM::NORCROSS_WTue Jun 29 1993 13:322
    Was that with or without your wife in the boat?
    
703.35MKOTS3::RONEYTue Jun 29 1993 13:507
    
    Wayne,
    
    Without, of course.........
    
    
    Bob
703.36Did she say, "We gotta have this boat!" :>)APACHE::URBANTue Jun 29 1993 14:443
    So tell me, how long did it take her to figure out it was a set up?
    
    Tom
703.37What Boat?SOLVIT::RONEYTue Jun 29 1993 15:4921
    
    Tom,
    
    One of the things that I had working for me is that I have quite a few
    friends that have performance boats. Sometimes they will come up to see
    us, more than one at a time. She is use to seeing boats of that caliber
    around even though she doesn't know one from the other. 
    When my daughter asked who owned the boat and I was silent, or didn't
    give an immediate answer, I think that got her wondering. It took til
    late Saturday afternoon before she asked.......
    And of course, in a sheepish kind of way, I said "we could be the new
    owners"! How does that phrase go, "Silence is golden".
    She's a real good sport about things. After all we've been together for
    over 23 years and as she said, haven't we been here before?
    
    Tom, do you think I have a chance when she starts asking questions like
    is this thing a "GAS PIG"?
    
    
    Bob
       
703.38flop/drip, flop/drip....GUCCI::HERBAl is the *first* nameTue Jun 29 1993 23:003
    ....and you were'n foolish enough to accept a beer before going those
    speeds were you? My experience on an Olds powered Checkmate (squirt) is
    that it will foam a beer out all over your lap within a minute.
703.39MKOTS3::RONEYWed Jun 30 1993 09:3715
    re.38
    
    No I didn't pop a beer! We didn't foam any beers, but boy that boat
    will get your attention when you stuff the throttle into the dashboard. 
    Who said big blocks don't go???
    
    I've been in other 25' Checkmates,but this one really is setup nice. It
    has a couple of bolt on goodies like a bullet cone on the Bravo drive
    and it's swinging a 25" pitch Mirage prop. Most 25' Checkmates will run
    in the low to mid sixties. This one will do 73.......... That's what
    the owner says. We came close. It was pretty calm when we went for a
    speed run. A little more chop in the water and we would have done
    better,
    
    Bob
703.40Gas Pig? It's all relative, eh?APACHE::URBANThu Jul 01 1993 09:0815
    I know what you mean about a good sport..mine reads me like a book.  
    In a way thats good cause it sets the
    expectations and allows you to work on getting the right 'mood' set
    before you start verbalizing the 'plan'.  
    
    Re: Gas pig?  What I would do is every couple of days be sitting with
    a boat magazine and casually relate some 'worst performance' figures,
    including GPH, MPG of the piggiest boats I can find,  Ocean racers,
    mega-yatchs, Queen Mary, who cares...avoid mentioning size, weight, how 
    many engines.  THen, when the question come up on the checkmate, tapdance!
    (e.g. "Well, depends on how you drive it.";)  It wont work, but
    your feeble attempts to pre-dispose and ultimate try to dodge may
    count for some points when the truth is told on the Checkmate!  
    
                   Tom          
703.41It's getting better!MKOTS3::RONEYThu Jul 01 1993 10:4617
    Tom,
    
    It's funny that you mention the stuff around various boats and being
    "GAS PIGS". There was a discussion last nite. Boy was it funny! 
    It started off with,"do you really want to spend that kind of money and
    only get to use the d_mn thing a half a dozen times a year? But Hon
    look at the fun we can have during those times. Will this thing be any
    better on gas than the one you had? Of course! I remember Ted's wife
    telling me that their seasonal gas bill for one year was $2700. What's
    this one going to be like? (Ted's boat is a 30' Formula with a pair of
    Mercruiser 400hp 454's, TRS drives etc.) The Checkmate is nothing like
    Ted's for gas consumption! 
    
    Round two, maybe this week-end at the lake with no boat and a house
    full of people.......
    
    Bob....I'm....still....trying........ 
703.42The Philosophy of Fuel ConsumptionROGER::GAUDETBecause the Earth is 2/3 waterTue Jul 06 1993 17:2513
Why is it that us people who obviously have the big bucks (we're boat owners,
we must have money oozing out of every crevice in our being :-}) are so
concerned about the "gas mileage" of our boats?  Someone once told me the
following in reference to a guy who walks into a Rolls Royce dealership and asks
the saleman, "What's the EPA rating of *that* car?" pointing to the $160,000
model on the showroom floor.  The salesman says, "Sir, if you have to ask that
question, you can't afford this car!"

Isn't it the same with our multi-thousand dollar joy-toys?  Sorry, long weekend,
many beers, terrific sunburn.  I know, I know, I'm preaching to the choir!
:-) :-) :-)

...Roger...
703.43just a referenceUSCTR1::BORZUMATOWed Jul 07 1993 08:3920
    
    Concern about fuel consumption may not always relate to the expense
    as a whole.
    
    I think most would agree on the following:
    
    1. If fuel consumption increases significantly there must be a 
       reason, therefore its a good idea to "keep an eye on it"
       Its just a reference.
    
    2. Depending on how you use your boat, lets says you need to travel
       a distance to get somewhere, offshore fishing, you better
       understand what you consuming.
    
    
    Sounds real rationale, i keep the reciepts and log the hrs. on the when
    i fuel, just as a reference.  If there is some relative consistency
    then all is relatively well.
    
    JIm
703.44Gas Tax Refund!MKOTS3::RONEYThu Jul 08 1993 10:337
    Jim,
    
    If you use that boat in N.H., don't forget to save the gas slips so you
    can turn in your tax refund at the end of the season.
    
    
    Bob
703.45Chevette --> Bayliner?KAHALA::SUTERNever too Hot!Tue Jul 13 1993 16:2818
>Note 1074.4              I/O Bottom end Engine knocking                   4 of 5
>DWOMV2::KINNEY                                        8 lines  13-JUL-1993 15:10
>                                 -< bad news >-
>--------------------------------------------------------------------------------
>    i have just heard from the mechanic 
>    The engine is lost.
>    he said the piston came of connecting rod and thru the cylinder wall.
>    he said i was looking at a bill of $2510.00 for rebuilt motor and labor
>    charges will amount to close to $800.00.
>    He had no explanation as to what would have caused this.
>    
>    row,row,row your boat.....
    
    
    	How about converting a JY 4 cylinder into the boat instead. Gotta
    be easier than performing the same task for a V8?
    
    Rick
703.46Upsize/upgrade opportunity ??ASDS::BURGESSWaiting for ZEUS to comeWed Jul 14 1993 12:4318
	For anyone in this unfortunate position,

	a) my sympathies (not worth much, I know)

	b) the suggestion that the 4.3 litre V6 will drop in almost 
	anywhere the 3.0 litre straight 4 comes out of - and will add
	substantially to the desirability of the boat.  One would have 
	to get prices, but I'd guess the price difference would be
	well worth it.  This is the chevvy/gmc small pick up truck
	engine. 

	c) a comment that I think the biggest size the gm 4 banger 
	comes in for cars and trucks is 2.8 litre, though most are 2.5


	Reg

703.47Big block runs strongHURON::VALLIERETue Jul 20 1993 10:5160

	To finish my story - per note 17.... 


	I purchased the Corvette big block for $1000.00. This motor was
	completely dissassembled and the parts that came with the block 
	were all new and high performance grade - pistons, rings
	lifters, etc. Everything had just come back from the machine shop. 
	Oddly enough, the machine shop had inserted brass freeze plugs for 
	the Corvette. We swapped out the cam from my original motor. Since 
	this was somewhat a foreign motor to us , everthing was measured to
	ensure all was in spec prior to assembly.

	The original 454 magnum (330 HP) was a 2 bolt main. When I made 
	inquiries to marinas to whether the the big blocks were 2 bolt or
	4 bolts (before I purchased the new motor)- I got very conflicting 
	information. I finally talked to a machine shop who builds boat 
	motors, he said that all 454's stock are 2 bolt mains. When he goes 
	beyond 500 - 600 HP - they will build it with a 4 bolt main.

	Anyway, the assembly went reasonably well - there were lots of little
	things like the oil dip stick was a different arrangement, the 
	starter had to be rebuilt, etc. 

	The mechanic charged for 40 hours and I had about 20 hours into it. 

	My expenses ran - 40 hours labor - $1085 ( he works pretty cheap)
			  motor		 - $1000
		    	  other parts    - $ 235

				total    - $2320

	I will be selling off my old block and heads so I figure this 
	inconvenience has cost me about $2000 for a new motor installed.
	It certainly beats the quotes of $3500 plus installation...

	I spent the last two weeks at Cape Cod with the boat. I did not even
	have to turn a screw or make an adjustment. I ran it about 25 hours
	over that time. I did not yet run it wide open so I do not have any
	real comparisons based on speed but the motor appears noticeably 
	stronger than my last motor. By the bore and compression, the new
	motor is about 410 HP. I ran it up to about 3800 RPM (thats about
	55mph and it was barely working..). I did notice an increase in 
	fuel consumption but I have not calculated it as I write this.

	The biggest concern with the new motor was detonation. We dropped
	down a heat range on the plugs and also backed off the timing 
	2 degrees. I am also running 93 octane. I periodically checked the 
	plugs after I ran the boat and they are fine. 

	My final analysis, no - I do not have a warranty on the motor but
	I do know exactly what I have and confident that it was put 	
	together properly. However, I feel a whole lot better that I have 
	25 hours under my belt. I know that I would not have been happy to 
	drop downto a 350 CI. After having the big block its just not the same.
	I am now anxious to put a few more hours on the engine, re-prop it 
	and see what this boat and motor can do....

	Ed
703.48Big Blocks are GREAT!MKOTS3::RONEYWed Jul 21 1993 11:2828
    
    Ed,
    
    Sounds like you did your homework and came up with a good package and
    satisfied your needs. I've had various types of 427 and 454 big blocks.
    Once you get a taste of that torque you're hooked! 
    
    That detonation concern is a valid one. Be careful, the compression of
    the engine may be the deciding factor for you. 
    
    In regard to what's got 2 bolt a 4 bolt mains. You mentioned that the
    454 MAGNUM (330hp) is 2 bolt. Point of information, 330 hp 454
    Mercruiser is a 7.4 litre. It's not a 454 MAGNUM. A 454 MAGNUM has 365
    hp at the prop and has 4 bolt mains with an aluninum medium rise intake
    manifold. Everything from there up in horsepower rates in Mercruiser
    engines has 4 bolt mains. i.e. 370 hp, 400hp, 420hp, 500+hp and then
    into the 502 c.i. blocks and bigger like 511, 572, and even 600+ c.i.
    
    If you run your stock cam you could probably run around 4800-5000 rpm
    with the right prop. As you know performance of boats also has alot to
    do with the type of hull and drive as well....... 
    
    Lots of luck with your new TOY..........
    
    Don't forget to save a few bucks for GAS. Once you start to use this
    beauty I think you are going to see your  gas consumption go to H___!!!
    
    Bob
703.49Exhaust manifold gasketsKAHALA::SUTERand now for something you&#039;ll really like!Mon Apr 01 1996 16:3211
	Geez, I know there's a note about Marine vs. Auto *PARTS* but
I sure can't find it.... and I'm the mod! This note will do...

	Anyone know if the exhaust manifold gaskets are something that
must be purchased as Marine, or will the local NAPA store carry the same
thing? This is for a 1987 351 PCM.

Rick

ps. The good news is that it ain't a lifter making noise!
703.50exhaust manifold gasketsFABSIX::J_KASPERTue Apr 02 1996 03:185
NAPA CARRIES A COMPLETE LINE OF MARINE PARTS.

THE EXHAUST GASKETS ARE NORMALLY A METALIC MATERIAL AND ARE THE SAME SIZE AND 
SHAPE AS AUTOMOTIVE, IF THE AUTOMOTIVE ARE OF THAT TYPE OF MATERIAL THEN USE
THEM   I DONT KNOW WHAT THE DIFFERENCE IN COST IS BUT I DONT THINK IT IS MUCH
703.51Don't need no snapped studs...KAHALA::SUTERand now for something you&#039;ll really like!Tue Apr 02 1996 09:5310
	Thanks Jack, I knew the head gaskets were different in some metallic
way, but I wasn't sure about the exhaust manifold gaskets. I'll ask the local
parts store about Marine version. If there is any justice in this world I won't
need to resort to NECC! :-)

	I am still very leary of removing an exhaust manifold DURING the
SEASON, but I may get over that....

Rick