3.8 Buick, FWD vs RWD ?

cowmilker

SUPER CHEESY
Is there a difference in the blocks of a 3.8 Buick through FWD or Rwd? Is there a difference between years? I know there would have to be different oil pan types, and maybe different heads (F.I. vs CARB ect) but are the blocks any different? If I were to start looking for a donor block to replace one that had freeze damage, what could I get away with? I would have the old oil pan, intake, ect. but are the blocks the same? Any info would be helpful.
 

mbryson

.......a few dollars more
Supporting Member
cowmilker said:
Is there a difference in the blocks of a 3.8 Buick through FWD or Rwd? Is there a difference between years? I know there would have to be different oil pan types, and maybe different heads (F.I. vs CARB ect) but are the blocks any different? If I were to start looking for a donor block to replace one that had freeze damage, what could I get away with? I would have the old oil pan, intake, ect. but are the blocks the same? Any info would be helpful.


Maybe.

I'd guess almost anything '91-'92ish or older can be either way, but somewhere around that time they started redesigning that engine about every year. Extensive research would be required. Check out the Buick forums. I'm sure they have a crossover sheet of some kind.......

Great engine! I'd like to dig up a RWD Regal (or other G-car) with FI.
 

Hickey

Burn-barrel enthusiast
Supporting Member
I would guess most of the differences would be in the intake design and maybe some of the accessories. I believe the blocks all have the same bell pattern, but there might be a few exceptions.
 

cowmilker

SUPER CHEESY
The reason I ask is because I have just bought a boat that has a cracked block from not being drained for the winter. The previous owner said he discovered it while he was driving the boat on the lake and water started coming in. This tells me that (probably) everything on the engine is in useable condition except for the block. I didn't notice any water in the oil, so I think there should not have been any damage from lack of lubrication to the heads, valves, ect. It looks like the ONLY thing that was damaged was the block, so it looks like if all the bell housings are the same (I was planning on going late 70's - Early 80"s) then I should not have much problem with switching them out.
Here is another Question for all you gear heads. If I do some investigating and find that the only crack in the block is from the outside, can it be welded, or patched in some way. I used to work at Checker, and one day as I was roaming the salesfloor trying to get to know my products as a good partsman should, and I was reading the back of some J B WELD and it mentioned that the city of Chicago used it to repair an engine block on a Caterpiller Diesel, do you guy's think it could work on a little boat engine? The coolant system on cars I have been told only runs on 10-15psi. Would a weld hold that much pressure? I know you can't, as a general rule, weld engine blocks, but can you patch weld?
The crack isn't by any stud holes so the only pressure it would have to hold is water presure. What do you think?
P.S. I know this is not a boat repair chat room, but I figure if anyone would know about broken parts and how to fix them, this would be the place to find those people!
 

Hickey

Burn-barrel enthusiast
Supporting Member
My brother had this same problem with his boat. It turned out to be a freeze plug that fell out. The freeze plug was behind the flywheel. You might want to check that before tearing into things.
 

Mcstiff

Registered User
Location
Greeley, Co
There is a good chance it is a freeze plug. If not, I wonder what it would take to put the S/C'd 3.8 in there? I am using one in my CJ6, it has the 60* chevy pattern.
 

cowmilker

SUPER CHEESY
I know it is not a freeze plug, the crack is in the front of the engine accross from the fuel pump. It looks like I will have to do a short block, so I will check into the chev 3.8 (until today I didn't know there was a chev 3.8 I thought all 3.8s were Buick), it could be that is what the old block is anyway. thanks for the tips everyone!
 

Mcstiff

Registered User
Location
Greeley, Co
Chevy, Buick, GMC, whatever it is all the same Co. My 3.8 is the supercharged version from a Grand Prix. I know they had a 3.8 in a Camaro.
 

cheapzuk

Registered User
Location
Saint George
My neighbor will sell you his buick 3.8 for a $100 if you are interested. Buick, olds, and pontiac are all the same. I wasn't aware of GM building a chev 3.8, are you sure it is not a 4.3?
 
Top