3.8 V6 OMC tune up questions.

doyoulikeithere

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Aug 21, 2004
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Hi I am having a problem with the engine running a bit too hot and I suspect that the timing is incorrect.
Can anyone please tell me the correct timing specs?
The unit is an early to mid eighties OMC Stinger with a 3.8 litre GM V6. I changed the carb recently from a rochester dualjet, to a quadrajet, and so I removed the distributor in the process. Now I can not seem to find the spec for ignition timing. Any help out there?

Thanks.
 

oops!

Supreme Mariner
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Oct 18, 2007
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Re: 3.8 V6 OMC tune up questions.

the omc 3.8 is actually a chevy engine.......
just set the timing as you would for any 3.8.

the guys here will have the actual specs.

however, timing is not allways the cause of a hot running engine.....have you checked the cooling system?

and by the way......from a former victoria-ite..........hi ! :D
 

MikDee

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Jun 6, 2007
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Re: 3.8 V6 OMC tune up questions.

Some of the early 3.8 V6's were Buick's, not Chevy's, it depends on the year?
 
Joined
Feb 13, 2008
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15
Re: 3.8 V6 OMC tune up questions.

My '85 Chris Craft uses the GM 3.8 and OMC 800 Stringer also. Here are the tune up specs I've used.

Ignition timing: 10 degrees BTDC
Spark Plug gap: .035
Point gap: .018
Dist. dwell: 34-38 degrees

My engine runs perfectly, hovers around 170 all day at idle or at speed, skiers in tow.. whatever. Hope this helps!

Good luck with that old OMC, don't take too much grief about it. Some of the guys here act like OMCs are the devil in sterndrive form and will really rag on you for working on it. Mines been a great powertrain, super reliable, easy parts to find and simple enough to work on.
 

doyoulikeithere

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Aug 21, 2004
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Re: 3.8 V6 OMC tune up questions.

Thanks Vintage Blue!!

I picked this boat up real cheap and I'm hoping to fix it up. Its a 17 foot ski boat with a 3.8 stinger 800. It had a bad carb on it when I got it so I put a new marine quadrajet on it. What kind of Horsepower should that make? What is WOT RPM for a 3.8? I think my 21 pitch prop is not steep enough because the engine would spin as fast as 6000 rpms if i let it!?!? Yikes.
Should go pretty good once i get it running good and cooling good.

thanks again for the specs.
i aslo looked for camaro, elcamino specs before i posted here but didnt find anything usefull. do you have a link to any good OMC info sources?
 
Joined
May 12, 2009
Messages
55
Re: 3.8 V6 OMC tune up questions.

i have your setup in a 85 beach craft, 17 foot. my gps says 50 mph at WOT.
 
Joined
Feb 13, 2008
Messages
15
Re: 3.8 V6 OMC tune up questions.

Thanks Vintage Blue!!

I picked this boat up real cheap and I'm hoping to fix it up. Its a 17 foot ski boat with a 3.8 stinger 800. It had a bad carb on it when I got it so I put a new marine quadrajet on it. What kind of Horsepower should that make? What is WOT RPM for a 3.8? I think my 21 pitch prop is not steep enough because the engine would spin as fast as 6000 rpms if i let it!?!? Yikes.
Should go pretty good once i get it running good and cooling good.

thanks again for the specs.
i aslo looked for camaro, elcamino specs before i posted here but didnt find anything usefull. do you have a link to any good OMC info sources?

I'm not sure about the horsepower numbers for that engine, my guess would be in the 140-160 ballpark when they were new. I have to admit that I've been pretty easy on my boat and I don't push any WOT runs. I have had it up close to 47-48mph, but that was in perfect conditions and according to the original speedometer. My boat had its original prop in place when I bought it and it was a 14.5 x 19 pitch. I've tried a 21 pitch, but the 19 seems to be the best all around for my needs. It's good enough for pulling me up on skis, I'm 6'2" and 205. It's also been a fine choice for just cruising. I usually run at 25-30mph.

As far as car engines go, I'm know the RWD 3.8 came in the 85 Monte Carlo, and likely whatever it's Buick counterpart was at the time. Regal maybe? And if you're looking for info resources... this place is it! Use the search feature and don't be afraid to ask questions. I've been lucky and I haven't had to post too much, I'm always able to find my answers in the archives. Oh, and get yourself a manual if you havent already. I've got a Clymer that is decent, but if you can come up with an OMC service manual, you'd be golden!

Good luck!
 

stacy21

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Jun 22, 2009
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Re: 3.8 V6 OMC tune up questions.

hi this is my first post i need help bad, i have a 1984 glassmaster 16' that has a 3.8 omc v6 i need to know what motor this is for a car so i can get parts for it from auto store , i spent 2 hours looking for a dis. cap there and still no luck if you can help i would greatly appreacite it
 
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