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Omc 3.8l

What’s really odd is even though I heard that GM sold the tooling to Kaiser Jeep I see that Buick ci tinted to use the 225 till 1967. After that they switched to the Chevrolet 230 cu in (4.1 liter) in-line six. So maybe Kaiser bought the engines from GM from 1965-1967 and then bought the tooling after Buick switched to the Chevy in-line 6.
The Buick V6 reappeared in Buick cars for 1975. But there must have beef some changes made because it was now 231 cubic inches or 3.8 liters.
That’s the same engine my wife’s family had in 2 cars, 1978 Pontiac and 1982 Buick.
 
I used an IA for help me to try😅
the AI explained to me that the OMC engine has a different bore than the Buick 225
It's difficult to find the exact dimensions of the segments and convert to européen standard (mm or cm)
Same for bearing crankshaft and rod bearing 😅
 
I think AI is wrong!
Because, those engines were bought directly from either Kaiser or GM depending on the year (Kaiser owned the tooling from 1967 on). I really doubt that GM made a special version just for OMC. Keep in mind OMC did not build their own inboard engines they bought them from GM, Kaiser and Ford. The only engines they built themselves were the Johnson & Evinrude outboards.


When it did change was in 1975. GM bought the engine back from the then owner of Jeep (AMC) the displacement was enlarged to 3.8 liters or 231 cubic inches.

So AI is confusing when GM bought the engine back from AMC with OMCs use of it in boats.

Sometimes the human is smarter than AI!
 
That will depend on the year of production. 1975 and later was 3.8 liters or 231 cubic inches. The early engines were 3.7 liters or 225 cu in. But all were built by either GM or Kaiser Jeep. OMC bought the engines and added marine specific components.
 
So if you take your OMC model #, you can figure out the year. Anything before 1975 should be the 225/3.7
 
So according to you the dimension of the pistons rings should be the same as on the 225 engine (which I look for on the Skylark)
Same for the crankshaft bearing and rod bearing?
It's not easy lol 😂
 
I think so yes.
But you are right, we are reaching WAY WAY back into the past, so it gets confusing.
It's similar for the Chevrolet 4.3, there are so many variations over the years of production (1985-2014) it gets really confusing. I had it easy, because on mine all I replaced were the cylinder heads, so what I did was just buy a pair of them where the casting number was the same as my originals.
Believe it or not on the Chevrolet 4.3 some of the differences were due to where the engine was built. There were 2 factories, one in Tonawanda NY and one in Romulus Michigan. How to know? There is a GM serial number on the block, it will start with a T for Tonawanda and an R for Romulus. Lucky for me I had an original engine, not re-done by anyone else. Here in the USA it is very common for a boat owner with a bad engine (cracked because water not drained in winter) to go to a junkyard, find a 4.3 out of a GM or Chevy truck, take it to a machine shop and get it rebuilt. There were literally millions of these engines made.
And for you, trying to do this in France, is much more difficult. Like rebuilding a classic Renault, or Peugeot here in the USA, possible but not easy.
 
Louc is right about the 225 vs 231 engines. I'm not sure of the exact sale dates from GM to Kaiser to GM. So perhaps the 1st OMC engines were sourced from GM then later Kaiser?

OMC used the 225 from 64 thru 72. 64, 65 & I think 66 had a 1 barrel carb, rated at 150 hp. Then went to 2 barrel rated at 155 hp.

You need internal parts for 64 thru 72 GM/Kaiser 225.
 
Thanks guys! I know and before I got sick I placed the order.
I've been lying in bed for two or three days to be sick 😅

Today i received my first order: crankshaft bearing, rod bearing and piston ring 👌
Obviously the bearings are identical 😁👌
 
Hello!
Si i'm fine now 🥵 "la grippe" is very bad!!
Last week-end i change crankshaft bearing and rod bearing, it's perfect!
I change pistons rings, perfect too 👌
Now i stay a kit engine rebuild ("all" engine gaskets 😁), for exemple i find the same kit in Europe is 180€ (186$) and on rockauto the similar kit is 76$, but with importation and delivery is 134$ 😅... I buy on rockauto of course 😂 i win 50€ 😅
I continue to take pictures and I hope to be able to send

Ohhh and i read in internet, this engine can work with e85 (in France e85 is cheaper than the 95 or 98 ) but not many engines work with it, except new vehicles with programming
 
Sounds like you’re doing great! They do have E85 here in the USA but I dont know of anyone using it in an engine with a carburetor. I do know that it is more corrosive than regular fuel. Not sure if the marine fuel pump and carburetor you have to use can stand up to the use of E85 fuel. Here it’s not recommended to use in an engine without modifications. I bet they know in Brazil because they are a big user of E85 fuel due to the fact it can be cheaply made from sugar cane…,
 
Ok i understand 👍 so i use 98 😅👌
Ohhh and i change Chain guide and tensioner for to be sure

The oil pump is ok, i just forgot to spotted the Delco, but I'd take an example from the engine I have in the boat which is set up and starts 👌
 
Post up some pix I’d love to see em. I love vintage engines especially ones I grew up with from the 60s & 70s…
 
Yes i want bug i've a bug when i want upload...

I have a problem with the oil pan baffle... I don't find this on internet, can you help me please?
(I loose the parts in my job when i go with engine parts for washing all parts...)
 
I’ll tell you I looked everywhere even in my old Motors Repair manual from the 70s could not even find a pic of it. Im
Guessing that the most likely source would be people who restore Jeep CJs because they used that same engine. I will keep looking but so far Il n’ya pas rien as you say in French…
 
(That's it, I'm getting there!)
Crankshaft bearing, rod bearing and pistons rings Reception
 

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remontage des culasses et de tous les éléments
Distribution (nouveaux tendeurs) avec pose du nouveau joint prêt à être refixé
 

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The top of the engine is easy and very quick to reassemble
I turned two rounds to check that I didn't shift the distribution, that's the basis
I also have to change the seals to the oil pump that I checked and clean (even the pressure safety)
The engine was given to me without the water pump, so I don't have the screws of the pump and I don't have the "big" screws of the distribution that are on the pump, if you have an idea to find them, because they are not European screws
 
I found the information for a similar bolt (but it's not the right length) but i don't understand the usa dimensions... The "big" bolt are 5/16 - 18x2 - 5/8 for exemple
I Want the 100mm lenght with similary bolt
 
5/16-18 is diameter & # of threads per inch.
2-5/8 is length in inches measured from under the head to end of bolt. Most likely not threaded the entire length.
 
It’s looking good. Nice simple basic American engineering circa 1962. Very similar to the other more common GM 90* V6s like the 4.3. What was done over time to get them to run smoother was a split journal crankshaft and later on a balance shaft. That finally made it as smooth as a V8.
 
One big difference between the Buick V6 and the Chevrolet was the distributor drive set up. The Chevrolet had it set up exactly like their V8 where the distributor drive gear was at the rear of the camshaft whereas the Buick had it off the front upper timing gear. On the Chevy there was just a simple tin front cover for the timing chain vs the Buick that had a bigger cover due to the front mount distributor.
 
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