Conference vicki::boats

One thought: the multiviscosity oils are made so by marvelous little 
molecules called viscosity index improvers (or something equally silly) 
that tend to come apart. Over time 10W-30 oil becomes more like 10
weight oil than 30 weight oil. And this is not good since a boat engine
spends most of its life under heavy load. And since most boat engines 
are only operated during warm weather, mulitviscosity oil isn't really 
necessary. 

    
    	Auto makers are also recommending against the use of extreme
    viscosity index extenders these days, particularly on diesels. 
    OK with most (US) manufacturers to use 10W30 or 20W40, but NOT 10W40,
    20W50, etc and beyond.  I think something (some kind of combustion
    by product, dunno what) eventually gets deposited up behind the
    piston rings and causes ring seizure (if you're lucky) or breakage
    and AWSH*T ! (if you're unlucky).  It's sudden too; and with the
    20+:1 compression in diesels its rumored to be VERY DRAMATIC, to
    say nothing of EXPENSIVE !
    
	Reg
    

    
    I hope I am not aggravating anyone by changing the topic slightly
    but,  how do people hear feel about using the manufactures own
    oil,  in my case Mercuisers Quicksilver Oil.  These oils are
    generally at least two times the cost of "regular" oils, are they
    really any better???  I am sure part of what you are paying for
    is the name,  but is there also something else???   The same goes
    for the filters.
    
    In the past I have been using the Quicksilver Oil,  my theory being
    that what is an extra $100 in oil over a numer of years, compared to 
    a $10K-$20K +  boat/investment.
    
    What do the rest of you think??
    
    /Mike
       
    
    

    Good point, Mike.
    
    I was told to use nothing but Quicksilver with my Mercury setup
    (oil-injection).
    
    When I stopped into Baerts Marine one day, the salesperson there
    told me there wasn't any difference between Quicksilver and brand
    XXX as long as its BIA approved.
    
    He even went so far as to breakdown how the oil is made and what
    Quicksilver has that the other don't ..... practically nothing,
    he said.
    
    I'd be interested in hearing what its all about because my owners
    manual highly recommends using Quicksilver and substituting only
    when necessary.
    
    Jeanne
    

    Back to the original subject and a bit of theory:
    
    Oil viscosity is measured used two different scales, normal which
    measures the viscosity at a temperature close to normal engine running
    temp (sorry I don't remember the exact degrees!) and the W-scale
    which measures somwhere close to water freezing point.
    (Just to complicate matters a bit further I tend to remember that
    the two scales are not equal in "grades" either, e.g. a 30W-oil
    at its measurement does not have the same thicness as a 30-oil at
    its measurment point!)
  
    The above means that e.g SAE 30 oil has a certain "certified" thickness at 
    normal running temperatures wheras we know nothing of its properties
    as cold, it could be like tar and still be sold as a SAE 30 oil! 
    Conversly a SAE 30W oil has a given thickness at freezing point
    but there is no guarantee that it woun't run like water when the
    engine reaches normal running temeratures. Of course no reputable
    brands of oil behave this extremely but there is nothing in the
    SAE rating system to prevent them from doing so. 
  
    A multigrade oil is "certified" using both the normal scale and the 
    W-scale.
    Consequently a SEA 10W-30 oil has the viscosity 10W at the lower
    temp point and 30 at running temperature. This is of course an
    essential property in a car engine that should be possible to start
    at sub-freezing temperatures and still get adequate lubrication
    when later reaching running temperature.
    
    Now, what does all this mean to boaters?
 
    Relevant points:
    1. Multigrades are usually more expensive than single grade oils.
    2. Multigrades don't seem to stand up to use as well as singlegraders.
    	(This is open to argument!)
    3. Multigrades usually contain more additives which again might
       cause unwanted phenomena like sludge clogging the filters etc.
    4. Boats usually don't need good starting properties at sub-freezing
       temperatures.
    
    So: If you are not going to run your boat in wintry conditions stay
    with single grade oils, multigrades are money down the drain and
    a (slight) risk to the engine!
    
    -jcl
   

SUB-TOPIC #1
	I use singleweight oil in any vehicle that constently is used under
a heavy load.  Sub-Zero temps. are another issue.  When switching back to
multi-grade oils for low temps., I just change the oil more frequently.
Works for me!

SUB-TOPIC #2
	Marine 2-cycle oils are produced by oil companies usually in the same
plant. For example, Merc, Johnson, Evnrude 2 cycle oil is all made by one vendor
with 2 second-sources.  The important item is BIA TC-W classification of that
particular oil, NOT the brand name.  Same I would content is true for 4-cycle.
Don't use "Jim-bob's local oil brand", but something like PENZOIL, QUAKER, CASTROL,
etc, with the appropriate certification STAMPED on the can.  Save you money for
the marina's inflated prices on Gas and related things you HAVE to buy from
them.

    
    Think I'll dust off this note and ask an oily question. I'm about to
    fire up my CrissCraft/Chevy inboard (vintage 1969) which is new to me.
    On the valve covers it states to use only 30W Marine Grade oil. Is
    there/was there such a thing as 4-cycle marine-grade engine oil? I'm
    thinking no, and/or that 20 years later, the oil you can get at your
    local Wal-Mart will suffice meets this standard. What say ye inboarders????
    
    BlueBeard

re                       <<< Note 194.7 by HEADER::STS_DF >>>
>                            -< <marine grade oil?> >-

    
>    Think I'll dust off this note and ask an oily question. I'm about to
>    fire up my CrissCraft/Chevy inboard (vintage 1969) which is new to me.

>    On the valve covers it states to use only 30W Marine Grade oil. Is
>    there/was there such a thing as 4-cycle marine-grade engine oil? I'm

	I'd be more interested in how long it has sat idle and how 
	much condensation is in the crank case right now.

	Yes, there was - yes, there probably still is.  Typically the 
	rating for single weight oil is higher than for multi-weight
	("multi-grade" ?).  So "fleet" oil for trucks and "marine" 
	tend to be specified where load is expected to be continuous
	and high.  Viscosity extenders probably aren't needed in most 
	marine applications anyway and bring some problems.

>    thinking no, and/or that 20 years later, the oil you can get at your
>    local Wal-Mart will suffice meets this standard. What say ye inboarders????

	Yes, its probably adequate.
    
>    BlueBeard


	Reg

I use Amalie HD 30W, in mine. I would also recommend Kendall.

If these are at Wal-Mart buy them.  As for a marine grade, i have 

personally never seen them. Before you crank up the old girl,

i would recommend you disconnect the coil wire, and roll it over

a few times, build up a little oil pressure from the turning then

fire it off. Should run fine.

JIm

    
    Stick with the straight weight popular brand names and you will not
    have any problems. Been using 30w for years and no problems in my Merc
    I/O. Merc recommends straight weights in their manuals.
    
    have fun and enjoy........
    
    regards,
    
    Bob

I've been using the Merc 25-40 weight 4 cycle oil. 1300 hours and still going
strong.

Steve

    What engine do you have?  I'm pretty sure that Chris Craft was out of
    the engine building business by then and using mostly Chevy blocks that
    were "marinized", which, other than being heavy duty engines (like four
    bolt mains) were not that different internally to their auto
    counterpart.  If you really have a Chris Craft engine which was based,
    I believe, on a Hercules or Continental block, I can get you a name of
    somebody who can answer your questions and probably supply you with an
    engine manual.
    Wayne