[mgarblik]

Couple comments about your successful repair. 1. You took some advice from the thread and tested out the suggestions. This included my incorrect idea that a valve cover may be the leak source. 2. You were willing to spend some $$ to buy a tool you can use for the next 20 years on all kinds of stuff. (smoke machine) I guarantee you will use this tool again or loan it to a buddy. 3. You didn't wring your hands over the solution and look for a short cut to fix it. You got right into it, did the job right, and are being rewarded with a dry engine. 4. You now own one of the few Pontiacs on the road that are really leak free! This is no small accomplishment. They are just a tough engine to seal, period. No way to sugar coat that. Congratulations and that is one beautiful car you have there. Looks like the Woodward Ave. Advertisement car. Fantastic.

[Verdoro 68]

This build has been such a long road - and a fun learning process - that I’m determined to get it right. In the 30 years I’ve owned this car, it’s never been leak free so it’s been a personal challenge to seal this thing up.

Sure was a ton of work, but it feels pretty good to know there’s no warning signs inside the engine after break in. In all the incarnations this engine has been through, it’s never had this good of oil pressure or run this cool. I feel like I’ve reached some sort of Pontiac zen where I have a leak free engine that runs cool. Hopefully I’m good to go for a while.

BTW, the Woodward ad has kind of been a loose template for me to follow. I’ve got a 24x36 poster of the ad signed by Wangers hanging in the garage.

[Verdoro 68]

If it ain't one thing, it's another. Got my plug wire issue solved and went for a cruise only to have the rear main eat itself again - this time way worse than before. I thought I had this thing licked with no leaks after a few hundred miles and a bunch of dyno pulls. It had it idling in the garage most of the afternoon as I dinked with timing and such and it was dry as a bone.

It blew cruising at a low RPM and was fairly sudden when it happened. Limped it home in a giant cloud of smoke leaving a trail of expensive Driven oil behind me. Fortunately I was only a mile or so from home.

Not sure what I could be doing wrong. I can definitely see pieces of seal collected around the rear of the crank and I think I'm even seeing chunks of seal in the oil that's dripping down from the pan. I might leave this next pass to a professional.

[Gach]

Just thinking…You could very well have a bent crank. And its taking out rear main seal.

[Verdoro 68]

The thought had occurred to me as well. I may take it to a machine shop and have it checked out. This sucks.

[Gach]

Only other thing I can think of looking at that oil pan, is that that pan takes the 3 tab rubber seal, which you don’t have in there and it could very well just be leaking there. Did you just use the cork gasket that fits on the main cap?

[grandam1979]

Well that suc** sorry to hear that hopefully you can get an idea of what happen when you take it apart.

[grandam1979]

If the block was line bored have it checked also if crank isn’t centered it will ride one side of seal.

[Gach]

Question did you used the cork gasket that fits in the main cap, then some black sealer over that, thats what it looks like. If thats the case that could very well be them problem, its hard to tell from the picture but thats what it looks like.

[Verdoro 68]

It was line bored in the last rebuild. When I was building it this time I noticed the #5 bearing clearances were .0010 bigger than the other journals. I made up for it with a different bearing, but maybe I should have looked at why it was bigger. When I tore it down a few weeks ago the main bearings all looked good so who knows what surprises await.

Originally Posted by Gach

Question did you used the cork gasket that fits in the main cap, then some black sealer over that, thats what it looks like. If thats the case that could very well be them problem, its hard to tell from the picture but thats what it looks like.

No, I used a BOP gasket with black sealer like the instructions say.

[HWYSTR455]

That's looking like a pan seal to me, but hard to tell from the pics. I've seen the rubber seals grow/squirm out, I never use them, my personal preference is the cork ones. I use the cork side rail gaskets too.

Think I mentioned before, I don't use OE type pans anymore, but it could be a pan problem. the rear portion could be stamped wrong.

Won't know for sure until the pan comes off. Bummer. I feel for ya!


.

[HWYSTR455]

I do the cork gaskets with gaskacinch, glued to the cap, and only RTV at the cap/block/pan joint. I go dry seal to pan.

I glue the cork side gaskets to the block, dry to the pan. Tighten after a couple heat cycles and it's good.


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[gtorich]

Originally Posted by Gach

Question did you used the cork gasket that fits in the main cap, then some black sealer over that, thats what it looks like. If thats the case that could very well be them problem, its hard to tell from the picture but thats what it looks like.

Might be the issue,...................i used the one piece bop oil pan gasket and the one piece rear main seal from bop...............the only thing i didnt do was use the cork gasket that goes in the main cap...............i get a small leak, about a drop everytime i use the car................pic im showing is a week or so how mine is leaking.

Sorry to hear about this...........think Mike is right on sealing a pontiac is a full time job.

Rich

[HWYSTR455]

You have to trim the cork gaskets slightly so they sit flush to the block. Some people curl them up and put a rubber band or piece of tape on them to 'train' them some before installing, but I've never done that I don't think.

Gasket to pan, I wipe the pan with acetone so it's clean & dry. Same with pan rails. Some after gluing them and dried wipe a little engine oil before putting the pan on, can't remember if I used to do that or not, been a while.


.

[Verdoro 68]

Pretty safe to say that it's the rear main again. Pulled this stuff out between the crank and the flexplate. So weird - it's almost like it unwound.

[Gach]

Originally Posted by Verdoro 68

Pretty safe to say that it's the rear main again. Pulled this stuff out between the crank and the flexplate. So weird - it's almost like it unwound.

WOW ! Ok if you had .010 more clearance not good, what was you able to close the clearance up to, should be no more then 3 thousands.

[Gach]

Man this sucks !

[Gach]

.010 more sounds like you were checking everything, I’m thinking what could cause that change ?

[Gach]

If it was line bored and your having this issue can only be one or two things bad line bore job, or the crank itself is bent, causing it to keep ripping the rear main seal out. I would put main cap on, torque it down and check it with a line bore gauge then mic the Crank, also would definitely check that crank for straitness. Still thinking

[Dragncar]

Originally Posted by Verdoro 68

It was line bored in the last rebuild. When I was building it this time I noticed the #5 bearing clearances were .0010 bigger than the other journals. I made up for it with a different bearing, but maybe I should have looked at why it was bigger. When I tore it down a few weeks ago the main bearings all looked good so who knows what surprises await.



No, I used a BOP gasket with black sealer like the instructions say.

If its line bored you need to sand the one piece some, test fit it in the cap and torque it down and look for little wrinkles in the seal. If it wrinkles you need to sand it some more and test fit and torque down again until the main seal is centered .
Its a pain but needs to be done.
Wade can help you out.