Conference vicki::boats

    
    	Does this sound familiar?? Hmmm........
    
    	I've got a Holley 4bbl downstairs, it's either a 600 or a 650.
    I think it's a 650. It came off guess what.... You are more
    than welcome to try it out, when I replaced it on Daze with a 
    new one, it didn't solve Daze's problem (that particular problem),
    so I assume it's fine.
    
    	The things you mentioned about playing with the timing, lead
    me to believe that maybe the distributor isn't feeling well.
    Have you checked the advance springs? I assume it's a manual
    advance rather than vacuum. The springs are cheap and available
    at the local speed shop.
    
    Rick

I also suspect the distributer. Possibly the timing chain...lord forbid.
    
    During the maiden voyage of my friends boat...the engine ran fine...
    
    ...up to about 2500 rpm, then she backfired all over the place.
    
    Problem: The timing chain. Not to say that this is your problem
    but it does sound like something mechanical rather than carb mixture
    problems.

    RE: .1
    
    The NAME of my boat?  Unfortunately the previous owner never gave
    it one and I've never thought about giving it one.  It's just "The
    Boat" to me.  I'm sure my wallet has a few choice names for it
    though... :-)
    
    I knew you'd find this stuff familiar, Rick.  I may take you up
    on your offer to borrow your carb if I don't get a new one soon.
    I want to run my boat before I winterize it but my other carb is
    in pieces and the intake is sitting with 4 holes in it right now.
    Maybe I'll borrow your carb just for the weekend.  Of course, I'd
    rather swipe your 351 PCM, but I'd probably have difficulty getting
    past the sentry!  :-)
    
    The distributor is vacuum advance, at least as far as I know.  It
    has one of those bell housings sticking out of the side with a hose
    that connects to the carb.  It is also a pain since it butts into
    the thermostat housing when I try to advance the timing.  May be
    time for some filing!  :-)  Good advice about the distributor (both
    .1 and .2) ... maybe I should consider a replacement there also.
    
    Curiosity forces me to ask this...what problem were you trying to
    track down when you replaced your carb?
    
    RE: .2
    
    I replaced the timing chain and gears when I rebuilt the motor.
    I remember that the chain was quite loose when I replaced it but
    I assume it's OK now.  The motor has only 25 hours on it since the
    rebuild.
    
    My backfiring seems to occur only way up in the RPM range, like
    near 4000.  I can cruise at 3500 without a problem, but when the
    motor feels the load of a turn near 4000 she'll start to spit and
    sputter (and it sounds like the motor is gonna jump through the
    motor box).
    
    					...Roger...

    If this engine has mechanical points (it sounds like it) then a
    prime suspect is point gap. Have you measured the dwell with a meter
    and adjusted while running or just used a feeler gauge ? My Mercruiser
    had a similar problem with stalling and skipping that a dwell meter
    fixed. Most of the time backfiring is an ignition problem. You should
    be able to watch the advance mechanism work by use of a timing light.

    Once again, if you have mechanical points, could be point float
    at high RPM.  Try replacing the points, perhaps with high RPM ones
    from a speed shop.

    I re-gapped the points with a feeler gauge and also adjusted things
    with a dwell meter.  This helped quite a bit, but it was still the
    advance in timing that cleared up the stalling-in-gear problem.
    I was told by several mechanic types that the carb jet screws were
    not working properly since they could twist them all the way out
    and the motor would not react.  I got a "live" demo of how they
    should work when I borrowed the 750 carb... a 1/4 turn either in
    or out (from the "right spot") made the motor start to choke.  I
    was told that there could be a problem with the metering block within
    the carb.  I am told that a real rebuild kit contains many gaskets,
    o-rings, etc. that are used to set this metering block correctly.
    I have no idea what my carb was set at when it was rebuilt.  When
    I got the carb back the guy said "I ran it around town on my Camaro
    and it felt good!" so I figured that meant it should run on the
    boat.  I did put an 8-degree angle spacer on the intake to level
    the carb out.  That seemed to help too, especially when setting
    the floats.
    
    But I still suspect that the carb is just tired...whatever that
    means.
    
    					...Roger...

    Roger,
    
    I am no expert at this stuff but...
    
    My car('78 V8) was having a backfiring problem when I tried to
    "punch it" at about 30 mph.  A after changing rotors, distributors,
    timing and carb settings someone suggested it may be the sparkplug
    wires( they were orginal equipment).  Put on a new set and it has
    worked great for the last two years.   Like I said I do not know
    if this is your problem but it may be something ELSE to think about.
    
    Good Luck,
    Mike Smith
    

    RE: Mike S.
    
    Another fine thought.  I certainly don't rule anything out, but
    I put a new set of wires on last year in my quest to resolve this
    problem.  As a matter of fact (and here's where someone may get
    a brainstorm) I ordered, direct from Ford, a special Motorcraft
    distributor cap with extra-wide wire contact spacing designed to
    "eliminate crosstalk with the distributor," so they told me.  The
    cap, of course, comes with a special extra-wide rotor, all of which
    fit perfectly on the existing distributor.  So I said "Great, I'll
    get some bionic wires to go with this new-fangled cap" and I ran
    out and got a set (for $30.00) of Cobra "Magnum" wires, 8mm bright
    blue with 18,000 levels of insulation and shielding, etc.  Seemed
    to run fine.  Thus, with new plugs, wires, rotor and cap, I think
    I've eliminated the electrical problem, at least from the top of
    the distributor.
    
    Therefore, you guys with the distributor suggestion have jumped
    right into an area which I haven't yet "replaced" so you may be
    on to something.  Any thoughts on things I may have overlooked when
    installing the new cap?  Special points too?  I put a set of "marine"
    points and condenser (that's what the cross-reference book said
    at the parts store) when I installed the cap.
    
    Just trying to eliminate the obvious first.  Thanks for your ideas.
    Keep those thoughts coming...gotta keep the ol' brain cells warm
    during the cold weather... :-)
    
    					...Roger...

    Roger,
    
    First, what did you do with the Camshaft when you rebuilt the motor?
    Change it? If not, did you previously have a 2-BBL carb? I f so,
    and you did not change the Camshaft to one designed for a 4-BBL,
    then that could be your problem. 
    
    Second, how do your valves sound as far as their adjustment? If
    you have the correct Camshaft-carb relationship, your valves may
    be too tight, causeing a "float" at higher RPM. You may also have
    weak springs on your valves, if the adjustment of those valves is
    correct. 
    
    Third, your carburetor doesn't have to be "dead" to have the idle
    screws seem ineffective; as long as the throttle plate is cracked
    off of "home" position, the idle circuits are cut out, and as such,
    the needle valves have no effect. The idle stop screw could be holding
    that plate open sufficiently to bypass idle circuits, making them
    screws look useless. Try setting them to initial settings--somewhere
    near 3/4 turn out from all-the-way-in. Then Tweak the idle stop
    screw (on the throttle linkage) counter-clockwise until the revs
    decrease. When the idle gets down to 750 or so, then try the idle
    mixture screws to see what they do. 
    
    Lastly, check the compression for uniformity. this could lead to
    uncovering a problem with a valve. (Where, oh where has my leaded
    gas gone?)
    
    Mike

    RE: .9
    
    Oh no!  The dreaded camshaft issue comes back to bite me in the
    *ss again!  Yes, I used to have a 2bbl carb on the engine, no I
    did not change the camshaft when I put the 4bbl on.  I know, I know,
    BIG mistake!  I've heard it from several folks.  And a big mistake
    it was.  At the time the $$$ savings seemed like a great idea but
    I see now that these things are doing me in.
    
    I will have to check on the throttle plate adjustment, etc.  I'm
    sure someone with the right know-how could get my old carb to work
    just fine.  I'm just at the point where I want it to work and
    replacement seems easier (though maybe not necessary) than repair.
    
    Valve adjustment seems OK.  I adjusted them a couple of times after
    installing the 4bbl carb (and new lifters at the same time).
    
    As far as compression, I did a test and all cylinders have around
    150 lbs., which is excellent compared to the 90 lbs. I had before
    I rebuilt the motor.  Actually it was the 90 lb. compression test
    that inspired me to rebuild the motor.
    
    Thanks for the tips.
    
    					...Roger...

    I would not worry about the cam being the wrong one.  Assuming
    you are looking for out of the hole punch, the cam designed for
    a two barrel carb will give you better low end torque and better
    performance in your cruising range - I would assume that you are
    looking for cruise RPMs < 4000.
    
    I would worry about the cam being timed properly given your 
    description.  One tooth off in setting up the timing chain will
    do it.  Before taking it apart, a dial indicator on the valve, and
    a degree wheel on the timing pulley will give you an idea.         
    
    Rick's idea about the advance is also a good place to look.
    
    As long as you are looking at a carb, I would avoid manual secondaries,
    as you need smooth increase from idle to full throttle.  One trick
    that I used with an 850 CFM Holly I had on a Chevy 396 and 454 was
    to put a screw through the secondary closing mechanism - this would
    pull the secondaries partially open, the vacuum would take it the
    rest of the way.  Also set the accelerator pump up for max squirt
    - who cares about the fuel economy when you only get 4-5 mpg in
    a boat anyway.
    
    RE the double pumper never had any experience, but I would think that
    it would be hard to drown a 289 with an accelerator pump, but opening a
    lot of throttle area with manual secondaries at low RPM could get it to
    bog.  I am assuming that the double pumper has manual secondaries.
                                            
    Don
        
    

    
    	Hmmmm, re  your old carb.  Have you tried a rebuild kit in it ?
    I seem to rebuild half a dozen carbs a year for friends and neighbors
    who have been told their carb is shot at ~50 - 60,000 miles and
    they need a new one for $N x 10**2.  The most expensive one was
    an '86 escort, complex as all hell, but still under $30 for the
    kit.  I have the dunking bucket and a gallon of fresh cleaner 
    [ Y'know, the stuff that burns the hair outta yer nose ? ]  if you'd
    like to try that some time lemme know.
    
    	Reg
    

    RE: Don
    
    Yeah, < 4000 RPMs is the range.  That's why I assumed that the existing
    cam was OK.  I figured that the motor was originally designed for
    the  boat, so low end torque should be the rule and therefore a
    cam with a max torque range in the 1500ish range should be there.
    
    That's a interesting idea about putting a screw in the secondary
    linkage.  That may help.  And I agree about the fuel usage thing...I
    am certainly not all that concerned with the fuel economy (or lack
    thereof) in my boat.  If I were, I'd own a sailboat (bite my tongue)
    :-) ...
    
    RE: Reg
    
    I know that the rebuild kits are cheap.  It's the expertise in
    rebuilding that's not necessarily cheap and pretty hard to find.
    I had the thing rebuilt a couple seasons ago but the guy "tuned"
    it on his Camaro.  Is it REALLY the same thing?  I mean, if it "ran
    good" on his car should I expect that it will "run good" on my motor
    (other problems like timing, etc. aside)?  I know a lot of gearheads
    that will gladly rebuild it, but I think a carburetor is a very
    sensitive device that needs not only the knowledge of someone who
    can put the parts in the right place but also those "special" things
    you need to do to get the maximum performance out of it for what
    the carb will be used for.  A boat is a tough place for a carb:
    it sits on an angle that's MUCH different from a car (at least as
    far as the floats are concerned), it doesn't get the air flow like
    in a car, and the engine is typically set up for a different power
    range than a car.  All this considered, shouldn't the carb be "tuned"
    for the boat environment?  Or doesn't it make THAT much difference?
    I mean, some things on a motor (the carb included) can be adjusted
    so the motor idles like $&%# but when you get above 3000 RPMs the
    thing kicks like there's no tomorrow.  I'm greedy...I want nice
    smooth idle, nice smooth transitions into gear, low end beef, and
    top end speed (without backfire).  Am I asking too much?  I say
    "no" because I've seen too many other boats with these capabilities
    and I want 'em too!  So there!  :-)
    
    So, how'd you like a rebuild job for the winter?  At your leisure.
    I'm not in a hurry (until about March or so) ...  :-)
    
    					...Roger...

    
    	I agree Roger, I've never re-built a carb  "for marine use"
    but I'd be willing to speculate as follows:-

    i)	It's almost certainly a different rebuild kit for the nominally
    identical (to a car) carb.
    ii)	The float(s) are set to a different level, there may even be
    different bowls due to the angle of installation you refered to and
    the  "bow up"  position during hard acceleration.  I know, I know,
    cars point up and slosh the gas back at take off too, but its more
    pronounced in a boat.
    iii)  Off-setting some of this is the wedge shaped carb mount/spacer.
    Your engine may be in the boat at about 15 degrees, but the spacer
    makes up for most of that and gets the carb close to level again.
    iv)	Jet sizes will be different too, lotsa  "schtuff"  will be very
    different in the slow idle area coz this is where most of the pollution
    stuff makes the cars different.  No smog pumps on boats, right ?
    Boats also run cooler.
    v)	If I went to a NAPA outlet for a rebuild kit they'd cross ref
    it and come up with a  "marine applications"  kit that would be
    different to what I'd get at a boat speed shop, i.e. it would be
    closest match.
    vi)	Rebuilding a carb from a boat and then tuning/tweaking it for
    best performance in a car might just do all the wrong things to
    it, see above.

    	I may try some questions at Land and Sea, either by phone or
    if/when I pass there again.  I don't have their number handy, will
    try to remember to post it next week.

    	Reg	{Oh, I got time this winter, we're only talking a half
			day, right ?  including the six pack.}

    
    	Oh, one more thing;  Air leaks.   Maybe its too obvious and
    maybe thats why no one else mentioned it, but back firing at high
    revs with OK idle and mid range would have me lookin' fer intake
    air leaks around the base of the carb probably.
    
    	Reg
    

    RE: Reg
    
    All very interesting observations.  I never really did any close
    checks on the possible air leak problem.  I guess I assumed that
    everything was OK.  Yet another area to explore in the spring.
    
    I'd appreciate you checking on those rebuild kits.  I'm interested
    to know what the differences are, if any.  BTW, did I mention I
    put an 8� spacer on the intake?  The carb sits pretty level now.
    This spacer came from a "performance rebuilding shop" and the package
    said "For marine applications" right on it.
    
    A half-day and a six pack?  If you're serious, the carb's in the
    mail!  :-)
    
    					...Roger...

Roger,

I know I kind of missed the boat but I am new to notes and DEC.
If your still having carb problems here are a few thoughts that
came to mind reading all your relpies:

-as far as carburetors are concerned the vacuum secondary series of 
4 barrels that Holley offers is not very intricate or complicated
and is in fact quite simple as far as carburetors go.

-When purchasing rebuild kits I always buy Holley replacement parts
for the particular application

-Holley sells different float kits with baffles to prevent fuel from 
sloshing around in the bowls.  One of these might be a good idea for a
carb on a boat motor.

-one can buy a good book on Holley carbs by HP books at some book stores
and at any speed shop.

-jetting makes no difference at idle since at idle fuel is being 
provided by the carbs idle circuit.

-the only special tool needed to rebiuld a Hollley carb is a clutch
driver to remove the secondary metering plate. a clutch driver resembles
a screwdriver with a bowtie shaped head and can be bought at sears for
about $8 with a bunch of difft. sized heads.

-a 289 with a mild cam and lo compression would need jetting between
Holley #66 and #70.

-mechanical secondary carbs(i.e. dbbl. pumpers) provide more punch off
idle and dont make any difference at higher rpm compared to vac. sec.
types.  Dbbl. pumpers also require a lot of fine tuning.

-electronic ignition is great.  it gets rid of a lot of headaches; you'll
never need to change points or set dwell or worry about an ignition
problem other than timing adjustment and it provides a much "hotter"
spark.

-if you opt for a new carb and don't want any head aches you should
consider a Predator carb. it is a variable venturi design that offers 
smooth operation and requires no adjustment or fine tuning just bolt
it on. It costs more than a Holley but offers head ache free operation.
it is most easily obtained through any mail order outfit that you'd
find in hot rod or any other such magazine.

The bottom line- I don't think your problem is your carburetor and if
you don't have a vacuum leak as suggested by another noter I would 
worry about your cam or cam timing. to me it sounds as if you might
have a worn lobe or two on your cam. if Reg rebuilds your carb this
winter and the problem continues this spring and gets worse as the
hours rack up that would point in this dirction. cams also wear out 
faster when you change the lifters because they were'nt broken in
together. when you do eventually do get a new cam I would suggest
that you "dial it in" for maximium performance rather than just
slapping it in.  cam timing is more critical on smaller engines
like your 289. the procedure for "dialing your cam in" can be found
in HP books "How to rebuild your small block Ford" which can be
found at many book stores and any speed shop like Forte's parts
connection in Waltham.

         
Good luck with your problem keep us noters posted on the results,

Tom

    Well Tom, first let me welcome you to the notesfile.  It's always good
    to have new folks on board.
    
    Second, thanks for all the good advice (also to all the rest of you
    folks too).  Since all this has been going on I've done some thinking
    about how to spend my chunk of our tax return and I think it will be on
    a new cam AND carburetor.  I know someone who mucks with race motors
    all the time and he had similar thoughts about the cam.  I think I'll
    yank the motor out one more time and have him do up the cam and maybe
    pop in the electronic ignition stuff as well.  I'll have to check with
    him on the $$$ issue but it sounds like a reasonable thing to do.
    
    So onward into the new year...any lakes melted yet?  :-)
    
    					...Roger...

    What about perfomance catalogs?  Does anyone know of any that deal
    with boats specificaly.
     

    Roger, it's a year and a half later.  What was the final resolution
    to your problem as I can see alot of the same things happening with
    my 260 Ford  (stalls when going into gear, breaks down at high RPM's).
    Thanks, Wayne

Wayne, the final resolution was a new carb.  I found it much less painful than
goofing around with the old one trying to replace a leaky jet and/or installing
an electric choke.  What I think solved my stall-in-gear problem was a timing
adjustment.  Now the idle is much smoother with the new carb, I don't have the
dribbling jet anymore, and no breakdown at warp speed.  For $200 (carb and
electric choke) it was well worth it.

...Roger...

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================================================================================
Note 1011.0                      Need new Carb                        No replies
PSDVAX::SCALA                                         7 lines  22-JUL-1992 17:44
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    looking for the best palce to buy a holly 4bl for a 350 pleasure craft
    marine engine (GM 350 block). Note 184 asked teh question, but no on
    ever answered the question. So one more time, where is the best
    (cheapest) place to pick on up in Mass/So NH. R.I.?
    
    thannks,
    Joe

    
    Joe,
    
    	Best place I found for a new Holley 4bbl is the speed shops. The
    last 650 I bought was "only" $144.00. They run specials on them quite
    often. The difference is the overflow tube which is for automotive
    purposes and sticks straight up rather than turning back down into
    the carb. Have we discussed whether this could be swapped from old
    carb to new before in this file?
    
    	Anyway, I didn't sweat it cuz the old carb wasn't a marine version
    anyway....
    
    Rick

    B & D Auto electric Co. Inc.
    60 Howard Street
    Watertown, Ma 02172
    800-852-3078  (inside mass)
    800-225-4217  (outside mass)
    
    Holley has a marine products catalog you can ask for.
    They list a model 4011 as a replacement for a rochester q-jet.
    The price I was quoted last year was $286, $31.69 for the fuel line
    and $14.18 for a linkage kit to work with mercruiser controls.
    
    KC
    

    I'ld like to see an answer to 184.23, also.  Is the only difference the
    down tubes for overflow?  I don't even think my carb (original obsolete
    Carter ABD two barrel) has them.  Probably not the law back in 1965 but
    I would be interested in putting them on if it can be done.  Does
    anyone have a friend in the carb rebuild business who could detail the
    complete differences between a auto and marine carb?  That's a big
    price difference for just a couple pieces of bent tubing!  You could
    make a business for yourself converting auto carbs to marine if that's
    all that needs to be changed.
    Wayne

    I was at the Amherst, NH, Antique Auto Flea Market Sunday and happened
    upon a guy selling a 4 barrel Holly marine carb for $25.  It looked in
    good, complete condition but probably would need a rebuild.  I would
    have bought it but I couldn't find anything on it saying how big it
    was.  I have a small block Ford engine (260 CU. IN., mild cam) and I'm
    sure I could overcarb it very easily.  Does anybody know how to tell
    the CFM rating of Holly carbs?  Also, can they be "downsized" (bad
    choice of words but I can't think of another) by changing the jets or
    metering rods if too big?  I would not want to go bigger than 600 CFM.
    One last question, do they use the same carb rebuild kits as the same
    size automobile carb?
    Thanks, Wayne