[79 Phoenix]

Originally Posted by 79 Phoenix

Good question: I don't see evidence on the engine and I think the guy I bought it from told me no oil leaks... On a Pontiac motor can you replace the rear seal without removing the crank?

Thanks again for asking this question. I hadn't thought about replacing the rear seal.

As far as I can tell there are 3 types of rear seals...a 1 piece, 2 piece vitron and 2 piece rope type... I don't like the rope type and would need to remove the crank to use the one piece... I might as well change the seal while I have it apart but would like to use the 2 piece vitron seal. I would need to lift crank slightly to put this in but not remove it all together.

Anyone know of a good source for the 2 piece vitron seal?

[tstroud]

If you use either the one piece or two piece seals you will need to remove the serrations on the crankshaft in the seal area or it will eventually leak. Ask me how I know.

[79 Phoenix]

Originally Posted by tstroud

If you use either the one piece or two piece seals you will need to remove the serrations on the crankshaft in the seal area or it will eventually leak. Ask me how I know.

Serrations on the crank?? What was the purpose? Do you have a picture?

[tstroud]

http://www.tinindianperformance.com/...ar-main-seal/#

[kingbuzzo]

I would highly recommend however if it is not leaking now you are playing the "will it leak" game either way - pontipigs are famous for this.

Some guys tilt them for a couple days just see the leaking before shoe horning them back in.

My mechanic forgot to change the seal, then it leaked like crazy, then bought the two piece after-the-fact, and it still leaks...fml

[kingbuzzo]

Verdero fighting with his rn apparently:

https://forums.maxperformanceinc.com...d.php?t=869548

[79 Phoenix]

Whew... Thanks guys for the education on Pontiac rear seals! I looked closer and there does seem to have been a little seepage on back side of the pan... possibly the rear seal. Doesn't look like it was terrible though.

After reading what you guys sent, I'm having second thoughts about messing with the rear seal. The reason I bought this engine is that it ran pretty good (according to previous owner and video he sent) and I didn't want to put a lot of money into a 350. Maybe I will just check out the rod bearings and leave the mains and rear seal alone.

[kingbuzzo]

I have given up for the time being...built in oil change lol

Maybe I'll give it another go when I win the lotto and get a new butler, and a butler while I'm at it 🙄

[Verdoro 68]

Originally Posted by kingbuzzo

Verdero fighting with his rn apparently:

https://forums.maxperformanceinc.com...d.php?t=869548

It was a battle, but I *think* I've finally conquered the seal (knock on wood).

What I learned is that the graphtite seal isn't as foolproof as it may seem. Then again, maybe I'm just a special level of fool LOL.

Given my experience, I wouldn't recommend installing any real main seal with a crank in place because of the cleaning and the prep required in the cap and the block. I'm sure it has be done successfully, just seems to add another layer of risk to a labor intensive procedure. You can't install the one piece with the crank in place anyway.

Lots of people say you can't use the Viton seal with serrated cranks, but Wade at BOP will tell you differently. The factory crank serrations are also way less aggressive than aftermarket cranks and more amenable to Viton. That said, I did have my Eagle crank polished down before I installed the one piece for insurance.

[kingbuzzo]

Yes, mine was factory crank, two piece, and likely un-prepared as hell...

[79 Phoenix]

[B]I have pulled the pan and rod and main caps off my "new" engine... I am going to replace the oil pump and screen... Any recommendations on the oil pump? I see there are 60# rated and 80# rated pumps. Which would give me the best oil pressure on this Pontiac motor? This is a stock 2bbl 350 .

Would a Melling pump be the best?

Also, it appears the rope rear seal has been working well. Unfortunately it looks like I will have to have the rod journals turned. So crank will have to come out./B]

[Verdoro 68]

M54DS seems to be the reliable go to pump. I went with a Butler prepared 60 lb pump and hardened driveshaft on my build. A little pricey, but I liked the improvements they added. You’ll get lots of opinions on 60 vs 80. IMO a 60 would suits most builds just fine.

[79 Phoenix]

Originally Posted by Verdoro 68

M54DS seems to be the reliable go to pump. I went with a Butler prepared 60 lb pump and hardened driveshaft on my build. A little pricey, but I liked the improvements they added. You’ll get lots of opinions on 60 vs 80. IMO a 60 would suits most builds just fine.

Okay, thanks. Mine currently is an M54D. Is there a difference between a M54D and an M54DS?

[79 Phoenix]

I got the crank out of my "new" used engine and took to the machine shop. It can be cut .01 on rod and main journals. BUT according to the casting number on the crank (#4813) my engine is a 74-76 350, not a 68- 71 like I thought. Apparently, the casting on the crank where the flexplate or flywheel bolt on changed in 1974 to a little different diameter so my flywheel (in back of original engine) won't bolt on.

Does this make sense??

[Verdoro 68]

Originally Posted by 79 Phoenix

Okay, thanks. Mine currently is an M54D. Is there a difference between a M54D and an M54DS?

Same pump. I believe the S is the catalog number meaning it came with a pickup/screen.

[79 Phoenix]

Originally Posted by Verdoro 68

Same pump. I believe the S is the catalog number meaning it came with a pickup/screen.

That makes sense-_Thanks!

[79 Phoenix]

Does anyone know if the 350 crankshafts changed after 1973? Or if there is any difference in the crank on a std trans engine VS an automatic engine?

[Baron Von Zeppelin]

Seems like I have heard about different size registers for flywheels before , but I don't remember how the story goes .

Did you ever go through all the date code drills on this new-used engine to ID the block and heads ?

Crankshaft should have more numbers in the casting number than what you posted.
At least 7 digits
After you get all your dates and numbers nailed down , you could post the question in the "Street Section"

[79 Phoenix]

Originally Posted by Baron Von Zeppelin

Seems like I have heard about different size registers for flywheels before , but I don't remember how the story goes .

Did you ever go through all the date code drills on this new-used engine to ID the block and heads ?

Crankshaft should have more numbers in the casting number than what you posted.
At least 7 digits
After you get all your dates and numbers nailed down , you could post the question in the "Street Section"

Unfortunately, I did not check this out before I bought the engine. I assumed it was a 71 engine. Okay, thanks that's helpful. I will look for more numbers... Also I am not that familiar with Pontiac engines. So I am learning.

[Baron Von Zeppelin]

The block code is STAMPED on the flat machined front face of the block.
Location is upper passenger side - where head bolts to block.
A 7 or 8 digit sequence number stamping , then a 2 digit application code.
The 2 digit code is the main ingredient.
For example will look something like this :
07798562
___ YN ___


The block casting date is located near the distributor hole.
It is CAST on the block in raised digits.
It will be 4 digits - with a fake looking screw head on each end.
Will look something like this :
@ B172 @


The head application code is CAST onto the head in bigger raised digits.
Located on top of the two center exhaust outlet ports.
For example :
11 .... or 33 ... or 4X

The head date code is CAST onto the head - on the outside - an inch or so below the valve cover.
It will look exactly like the Block Date Code described above.

You can check these on both your engines.