Oil pan gasket sealant?

XP29 · Post by **XP29** » Wed Jul 15, 15 5:06 pm

Hi guys. I'm trying to trace a slight oil drip and think I have it down to the oil pan gasket at the rear where it meets the flywheel cover. I have a gasket already but it says to use a thin bead of sealant on each side. What would be the best stuff to use? Also it looks quite close to the steering bar that is under there. Should I be able to get the pan out while the steering bar is there?

Pete · Post by **Pete** » Wed Jul 15, 15 5:27 pm

I think it is most likely that the drag link will have to come off....you may get away with it if you can lift the engine using a hoist and undo the engine mounts....

...just to note - a key weakness from an oil-tight perspective is NOT the sump but the rear main seal. Originally these were Rope, and later ones and replacement parts are neoprene.

They are NOTORIOUS for leaking.

Replacing them is not an easy job, but again it can be done in the car, and yes, the sump needs to come off.

It may be worth a really good inspection to confirm just where the leak is coming from as you may end up changing the sump gasket and then have to do it all over again as the root cause was the rear main seal.

For reference: we spent HOURS trying to solve the rear seal leak on the race car, and we made some progress, but we still wipe the sump / bell-housing off after ever 2 or 3 runs to avoid being pushed back....

Blue · Post by **Blue** » Wed Jul 15, 15 7:06 pm

I assume you've tried installing the seal rotated at about 45 degrees rather than having the ends line up with the pan rail? Seems to be the hot tip on big blocks these days.

XP29 · Post by **XP29** » Wed Jul 15, 15 9:14 pm

Pete, what is a drag link?

Can I see the rear main seal if the flywheel cover is removed and I look up there? Or at least an oil run to indicate if that's the problem?

They are bad for leaking on air cooled VW engines. On those if a after market one is fitted they still leak, but if a genuine VW is they don't.

I'm going to pull the flywheel cover off again and take another look.

Blue, I don't get what you mean by rotated 45 degrees?

Pete · Post by **Pete** » Wed Jul 15, 15 10:43 pm

The proper name for what you called the steering bar is the Drag link.

Blue is referring to the slot or channel into which the Main seal fits - some engine builders do not put the seal in alignment with the parting line between Block and the Seal retainer, they rotate it so that the seal has potentially better coverage to guard against leaks..

XP29 · Post by **XP29** » Wed Jul 15, 15 11:28 pm

Thanks Pete,

I'm with you now regards drag link. I still have lots to learn!

Ok, I'll get the flywheel cover off and see if I can determine where it's leaking from. When I looked in there earlier it didn't seem to be wet, but I'll give it all a wipe down and run the engine and see.

Pete · Post by **Pete** » Thu Jul 16, 15 7:43 am

Maybe you can just get away with nipping up the pan bolts, you never know; just do not over-tighten!

XP29 · Post by **XP29** » Thu Jul 16, 15 10:21 am

I'm a bugger for over tightening things

I'm hoping to get a look later today, there is some orange coloured sealant in there from when it was put together. What is the sealant you use on the gasket?

When I get the flywheel cover off, if I have a rear main seal leak, will I see obvious signs up through there?

MilesnMiles · Post by **MilesnMiles** » Thu Jul 16, 15 10:29 am

Just check it isn't the rocker cover at the rear dripping down. I had that and could only spot it with a mirror. Easy fix.
As for the sump removal, might try rotating the steering to fill lock and see it it gives sufficient clearance. Worked with my car for fitting headers.. Instructions said to remove the steering linkage, but I didn't need to.

morgan · Post by **morgan** » Thu Jul 16, 15 10:38 am

Its only the oil, transfluid and power steering leaks that have preserved the underside of my car so well ! Cant fix all of 'em...

Pete · Post by **Pete** » Thu Jul 16, 15 10:46 am

Yep, the rocker boxes are often the culprit but you should be able to see or feel a trail.....

MrNorm · Post by **MrNorm** » Thu Jul 16, 15 11:59 am

If it is the seal....make sure it is in the correct way round. Not a BB guy but have seen much debate on this and I understand it can happen

XP29 · Post by **XP29** » Thu Jul 16, 15 9:54 pm

Righty, I've been under the car, took flywheel cover off and wiped everything down. It wasn't obvious where it is coming from. I took it a run round the block to get the oil moving, had another look and still couldn't see an obvious leak. Although there was nothing coming out of the oil pan gasket or when I looked up through the hole when cover was removed. So I need to keep an eye on it. Really appreciate everyone's advice

XP29 · Post by **XP29** » Mon Jul 20, 15 9:37 am

On Saturday I took the car a run up to Sheffield from Essex. I was trying to stick at 60-70 but found I kept creeping faster than that. When I got to Sheffield i noticed it was dripping again. The spot on the floor was bigger which I took to be that I had been driving faster and longer than normal so more leak. I checked level and it had dropped from max to half way between mark on stick. On returning home it had dropped to the fill mark, so I need to address this issue. On looking at the engine I noticed oil in the valley pan, around the dizzy area and it looked like it had run out and down the outside of the gearbox. I cannot see an obvious place where it's coming out but I'm thinking it has to be the rocker gaskets?

I did change these a few months ago with the rubber type, I may have over tightened the bolts and I did not use any sealant on them (the old cork ones I took off did have sealant on). Is my best option to take the covers off and check they are flat then use a sealant such as Loctight Black on each side of the gasket?

Other than that the car drove great and I had a ball as it was just me and the car and the first long trip I've done in it.

MilesnMiles · Post by **MilesnMiles** » Mon Jul 20, 15 9:42 am

Only time I had oil loss like that was from the sump gasket which had been bodged on by a crap mechanic (not me, that time), but it was a very obvious leak with oil everywhere.