Oil leaks after rebuild, Dropping motor to track down oil leaks Options

[Wew]

Hi all,

Engine rebuild has not gone as smooth as I had hoped.

I am dropping the engine again to figure out the source of my leaks.

I have drips coming from a couple of the tube on the passenger side under the oil cooler.

Tough to tell if it's the cooler or the tubes.

Cylinder 3 is giving me the most concern.

It almost looks like one of the four cylinder studs is leaking oil.

I can't tell exactly as it could be the actual mating surface of the cylinder and the block.

Anyway I am dropping the motor to track these down.

Has anyone else come across oil leaking out of a stud or is this just the cylinder and engine mating surface leaking?

If it is how have any of you remedied this?

Is there a bullet proof sealant that others have used to stop this?

Attached is an image I borrowed online that shows the location of where I see oil coming from.

Thanks for sharing as always.

[Wew]

Are the 1973 2.0 engines supposed to have the pushrod clips?

[Mark Henry]

Where's the underside cooling tin?

What did you use to seal the cylinder to the case ?
Studs I put in with red loctite.

I'm happy if I have no drips, slight weeps are a given...it's an aircooled.

[Wew]

Hi Mark,

I removed the tin to see the leaks.

I used the permatex brown and the permatex white pasty stuff aviation stuff Jake Raby recommended on his video.

When I did my 911 engine it was all about the red loctite and the case is bone dry.

On the 914 I plan on loosening the bolt/stud and sealing with the red loctite.

A couple of the oil lifter return tubes are dripping as well. They all have the new green seals on them. So I will have to inspect and see what the problem is there.

I have a sneaking suspicion the oil cooler is leaking as well, as I think my local volkswagen air cooled shop sold me an oil cooler that is close but not exactly what I should have on there.

Other than putting the news seals on, which I have, and torquing the cooler down correctly, any other secrets or voodoo that is done to keep that part from leaking?

Thanks again for the response.

Gary

[76-914]

Don't overlook the oil pressure sender or more specifically where it screws into 8mm hole. If that leaks it runs down the cooler and will fool you into thinking the cooler is leaking. (IMG:style_emoticons/default/beerchug.gif)

[Wew]

sage advice... Will check there as well.

I hate oil leaks...

Love 914's

[Mark Henry]

So you took the pushrod tubes out to remove the tin and then replaced the pushrod tube to take the pic? I'm talking about tin that screws to the case and the head with the small M5 bolt.

Different builders use different sealants so I'm not saying anyone is wrong but under the cylinders I use loctite SI 5900. Yes it's an RTV, it's also Porsche spec on the newer engines.

[Wew]

ahh...

That is a photo I borrowed from another use to represent, show what I am working with.

I will take actual photo of mine and share, but for representation of what I was asking that photo shows the stud/bolt and one of the locations the oil is coming from.

Heading home from work shortly and will take actual photo of spot prior to engine drop.

Thanks Mark.

[Mark Henry]

Okay as long as you have those tins, your engine and the cylinder bottoms will fry without them.
The engine needs all the tin, an overheating engine will spring leaks.

Also make sure it's not pushrod tube leaks, it's real easy to cut one of those green seals as you install them.

[Wew]

Dropped the engine tonight.
That’s about all I can do for this evening.
Oil in the ssi reservoir.
I forgot to unbolt the transmission ground straps, like a dumbass.

Pulled the bolt right off the stud. Doh!

More Friday.

Gonna watch the nfl draft and see who the niners pick tomorrow.

[iankarr]

Four of the cylinder head bolts/studs pass through the case. If you didn't use any sealant on those, it's definitely possible some are leaking. And we've all forgotten the ground strap. It's a rite of passage.

[Wew]

Thanks for softening the blow Ian.

Mark, I couldn’t get a good picture of the stud with the tin on.

I was able to see it with one of those tiny snake camera with screen.

That a lot of oil in the pic of my ssi and it looked as though one of the copper exhaust bolts at cylinder 3 had oil on it.

Left side is bone dry.
Plot thickens.

Will report back soon.
Thanks again for all the input.

[Mark Henry]

Looks like the PR tube at the head, then it's migrating down the tube and the cooling air blows it off in that spot. Or it could be a VC leak. Less common is leaking at the rocker stud.
But also check the oil pressure switch, etc.

[Wew]

Thanks Mark.

I removed the fan housing shroud.

I have read through the threads and the PO hooked up a brass angled extension.

I remember being careful tightening it down, and not over tightening.

Based on the write ups it sounds like the brass extender sets up the location for a leak.
It is a VDO sending unit.

Oil cooler leaks and the air cooled shop provided me with a slightly different cooler.

I have since purchased the cooler specific for our cars.

The seals are orange colored. Putting this out there to see if there is another type that is recommended.

There was also a little oil sitting in the fan shroud right below the fan. I did not see any evidence of a leak at the front main seal.

It is close to the oil pump and will investigate that further.

I am also going to confirm that the oil return tubes are set properly.

Really am interested about hearing what is the best time tested way to fix that pressure sender unit leak.

As always thanks for all the input.

Gary

[Wew]

Two examples of the set up from PO.

Considering putting in the old school sensor that sits flush on the case.

Seems it would minimize leaks.


Thoughts?

Thanks!

[Mark Henry]

I personally would use a whip. That fitting and a grease gun whip the NPT threads are super close and it will work, but they are not quite correct. There was a guy on the samba selling SS whips with the correct metric thread. With a rubber grease gun whip you have to ground the body of the sender.
Use liquid teflon pipe dope, loctite 565 or permatex 56521, but DO NOT over tighten!

Everything has to be spotless clean, install without dope till fairly tight, note how deep it went, remove, clean again, add dope and tighten only to where it stopped before.
It doesn't have to be good and tight, the dope will stop it from leaking.

[FlacaProductions]

If you want to keep the gauge, you may want to re-think that sender set up and move to a hose to relocate.
https://www.pegasusautoracing.com/document....DocID=TECH00129
and then there's this to consider:
https://vwparts.aircooled.net/VDO-80psi-Oil...m-p/v360006.htm
I haven't done it yet but getting ready to install the 42 Draft Designs breakout (no longer being manufactured) and planning on using the OEM sender for the idiot light and the single pole sender dedicated solely to the gauge.

Lots of info here if you search "oil temperature sender"

[Wew]

That great info from both of you.

I got a better shot of the oil pressure opening after removing all the tines and I fuel injection and exhaust.

That opening is beat up.

I am still hopeful the loctite will be able to solve this problem.




Thanks again,

Gary

[76-914]

So it was OP sender.That looks like it is chipped all the way down the threaded area. No amount of pipe dope will seal that. You can get that area TIG'd then re-tap it. (IMG:style_emoticons/default/sad.gif)

[Wew]

Yikes,

Not what I wanted to hear.

Can this be done with the engine intact or are we talking complete tear down to make this happen?

Thanks,

Gary