U20 Oil Leak/HG?

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jasmith1975
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U20 Oil Leak/HG?

Post by jasmith1975 »

Happy Friday All! It's a crisp, sunny day in Buffalo and hoping to log some miles over the weekend. But first I need a sanity check on an oil leak.

After putting on a couple hundred miles over the several weeks, I noticed an oil leak. Looking under the hood, it seemed to be coming from the back corner head gasket (passenger side). Pulled the valve cover and retorqued the head bolts. Went in sequence per the Tech Wiki, starting first with 43 ft/lbs. All good there. Then moved to 65 ft/lbs in the same sequence. Bolt #9 (corner with the leak) moved quite a bit. Got everything torqued down to spec and closed back up. Took her for a spin and no leak...at least there anyway. Oil was now pooling on the block (same side) near an oil line (?) that runs between the block and the dizzy. Threw a wrench on the nipple and another on the line fitting...nipple didn't move, but the line connection did. Took her for another spin and the leak on the block looks to be fixed. Of course naturally, the corner head gasket is starting to leak. Again. :x

I haven't checked the head bolts again, but wondering if this is a common problem? Any ideas/solutions to try? I don't believe the HG has been done (only 30k on the car), but wondering if it's needed and/or if the head might be warped.

Appreciate any thoughts
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Re: U20 Oil Leak/HG?

Post by notoptoy »

There is another recent thread that addresses this issue. It appears that ultimately the head gasket was installed incorrectly (reversed/upside down)and the metal ring in the gasket that is supposed to be surrounding the oil galley was apparently not where it should be. This could be a similar issue. Also, one of the head bolts is slightly longer than the others, it is to hold down the engine lift hook. It should be at the rearmost driver side position, and I believe it has a different number/pattern stamped on the head of the bolt versus the others.
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Re: U20 Oil Leak/HG?

Post by MattC »

Hey Jared,

Mine had a little leak just like that when I bought it. Pulling the head showed that the gasket was pretty trashed, especially in that corner. I did the gasket and a few other things since I had the head off, including swapping in head studs. All fixed, no leaks!
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Re: U20 Oil Leak/HG?

Post by jasmith1975 »

notoptoy wrote: Fri Oct 02, 2020 2:50 pm There is another recent thread that addresses this issue. It appears that ultimately the head gasket was installed incorrectly (reversed/upside down)and the metal ring in the gasket that is supposed to be surrounding the oil galley was apparently not where it should be. This could be a similar issue. Also, one of the head bolts is slightly longer than the others, it is to hold down the engine lift hook. It should be at the rearmost driver side position, and I believe it has a different number/pattern stamped on the head of the bolt versus the others.
Thanks notoptoy. I read through the thread with the incorrect HG install. I have a lot (I mean A LOT) of service records and there's no evidence the HG was replaced, so thinking that may not be the answer. Then again, who knows?

I see there are 5 "long" bolts for the drivers side and 5 "short" bolts on the passenger side. Those all look to be installed where they need to go. Maybe some (or all) of the bolts were overtorqued at one point? Except for the rear most passenger (where it was leaking) all the other bolts didn't budge at 65ft/lbs. But who knows if they were torqued more than that. Maybe I loosen them all in reverse sequence and then go through the retorque procedure again to ensure 65ft/lbs across the board? If that doesn't work, wondering what's the next step...is locktite an option on head bolts? Maybe just replace the HG and have the head checked for warping?

Hoping to drive it a few more times and will keep and eye on it before popping the cover again.
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Re: U20 Oil Leak/HG?

Post by Gregs672000 »

The head gaskets are known to leak at the back oil return. The oil line referred to is also known to leak time to time and is not related. Things can get a bit dicey retorquing a head with 1) unknown head bolts and 2) in possibly oiled holes which will change the torque value, either of which could result in a broken head bolt if you overdo it.

The current leak is irritating but not dangerous, so drive the car and enjoy the last few drives before you decide to take it off the road and fix it. You can certainly try retorquing the head by backing them off a bit and progressing through them again very carefully. It may stop if they were not torqued adequately before. You run the risk of a broken bolt so don't overdo it. If that fails, the only (and best) solution is to do a head gasket, get new bolts or a stud kit, be sure to use the improved head gasket that has a seal around that area, and check the head for flatness.
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Re: U20 Oil Leak/HG?

Post by jasmith1975 »

MattC wrote: Fri Oct 02, 2020 3:04 pm Hey Jared,

Mine had a little leak just like that when I bought it. Pulling the head showed that the gasket was pretty trashed, especially in that corner. I did the gasket and a few other things since I had the head off, including swapping in head studs. All fixed, no leaks!
How about pizza, beers and an available weekend? 😂 Guess I'll have a HG job staring at me this off-season. Cringing as my only attempt at one was on a VW some 30yrs ago, that after put back together found it had a cracked head. 🤦🏻‍♂️ Let's hope this time around has a better outcome. Older, debately wiser and alcohol involved. What could go wrong?!
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Re: U20 Oil Leak/HG?

Post by jasmith1975 »

Gregs672000 wrote: Fri Oct 02, 2020 4:18 pm The head gaskets are known to leak at the back oil return. The oil line referred to is also known to leak time to time and is not related. Things can get a bit dicey retorquing a head with 1) unknown head bolts and 2) in possibly oiled holes which will change the torque value, either of which could result in a broken head bolt if you overdo it.

The current leak is irritating but not dangerous, so drive the car and enjoy the last few drives before you decide to take it off the road and fix it. You can certainly try retorquing the head by backing them off a bit and progressing through them again very carefully. It may stop if they were not torqued adequately before. You run the risk of a broken bolt so don't overdo it. If that fails, the only (and best) solution is to do a head gasket, get new bolts or a stud kit, be sure to use the improved head gasket that has a seal around that area, and check the head for flatness.
Good call about oiled holes. Forgot how that can change the torque. Sounds like best to do the HG and be done with it. Anything else you recommend doing while the head is out? I might as well be proactive with the engine split apart. Many thanks!
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Re: U20 Oil Leak/HG?

Post by MattC »

jasmith1975 wrote: Fri Oct 02, 2020 5:55 pm
MattC wrote: Fri Oct 02, 2020 3:04 pm Hey Jared,

Mine had a little leak just like that when I bought it. Pulling the head showed that the gasket was pretty trashed, especially in that corner. I did the gasket and a few other things since I had the head off, including swapping in head studs. All fixed, no leaks!
How about pizza, beers and an available weekend? 😂 Guess I'll have a HG job staring at me this off-season. Cringing as my only attempt at one was on a VW some 30yrs ago, that after put back together found it had a cracked head. 🤦🏻‍♂️ Let's hope this time around has a better outcome. Older, debately wiser and alcohol involved. What could go wrong?!
My keto diet won’t allow for pizza or beer but I don’t need much of anything to twist my arm into helping on a roadster project. I had my head off twice this spring for different reasons. I’m pretty comfortable doing it at this point. Shoot me a PM or email when you want to make an attempt!
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Re: U20 Oil Leak/HG?

Post by theunz »

Good call about oiled holes. Forgot how that can change the torque. Sounds like best to do the HG and be done with it. Anything else you recommend doing while the head is out? I might as well be proactive with the engine split apart. Many thanks!
[/quote]

Obviously a valve job comes to mind, but it’s also a great time to replace the timing gears and chains. If you suspect your water pump to be the original or has lots of miles on it now a good time for that also.
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Re: U20 Oil Leak/HG?

Post by JT68 »

Before you pull the head! That leak looks like it is below the tach cable. Reach under it and check for oil.

The head leak is usually at the very back of the head where it meets the block.
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Re: U20 Oil Leak/HG?

Post by jasmith1975 »

JT68 wrote: Fri Oct 02, 2020 8:20 pm Before you pull the head! That leak looks like it is below the tach cable. Reach under it and check for oil.

The head leak is usually at the very back of the head where it meets the block.
Yep, picture was of the oil line leak between the block and the dizzy. Snugged up the line and seems to be dry...for now anyway. Back corner of the head gasket is definitely leaking.
theunz wrote: Fri Oct 02, 2020 7:28 pm Obviously a valve job comes to mind, but it’s also a great time to replace the timing gears and chains. If you suspect your water pump to be the original or has lots of miles on it now a good time for that also.
Good advice. I'll start working up a punch list of items. How about any other gaskets or seals to proactively replace?
MattC wrote: Fri Oct 02, 2020 6:07 pm
jasmith1975 wrote: Fri Oct 02, 2020 5:55 pm
MattC wrote: Fri Oct 02, 2020 3:04 pm Hey Jared,

Mine had a little leak just like that when I bought it. Pulling the head showed that the gasket was pretty trashed, especially in that corner. I did the gasket and a few other things since I had the head off, including swapping in head studs. All fixed, no leaks!
How about pizza, beers and an available weekend? 😂 Guess I'll have a HG job staring at me this off-season. Cringing as my only attempt at one was on a VW some 30yrs ago, that after put back together found it had a cracked head. 🤦🏻‍♂️ Let's hope this time around has a better outcome. Older, debately wiser and alcohol involved. What could go wrong?!
My keto diet won’t allow for pizza or beer but I don’t need much of anything to twist my arm into helping on a roadster project. I had my head off twice this spring for different reasons. I’m pretty comfortable doing it at this point. Shoot me a PM or email when you want to make an attempt!
That would be great. I'll provide the keto friendly snacks. Thanks Matt. 👍🏻
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Re: U20 Oil Leak/HG?

Post by MattC »

I did valve seals while I was in mine. Pretty easy once I got the process for releasing the springs down.
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Re: U20 Oil Leak/HG?

Post by jasmith1975 »

MattC wrote: Sat Oct 03, 2020 7:13 am I did valve seals while I was in mine. Pretty easy once I got the process for releasing the springs down.
I'll add it to the list. Will start digging through records and see what's been done and when.
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Re: U20 Oil Leak/HG?

Post by Gregs672000 »

Before you dig into it, I would fully clean the oiled area until it's free of oil, then run the car and confirm it's actually coming from the head gasket... as JT68 said, there are other sources of oil, and oil can travel. Some people lightly dust it with baby powder to make it stand out more clearly. Doing a head gasket is not "hard" but it is an involved and learning process. Help is good to have, but regardless you have lots of support here.
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Re: U20 Oil Leak/HG?

Post by nismou20 »

Passenger side rear on U20 known to be problematic leak area. Earlier HG were made without the reinforcement at the oil gallery and thus leaked a lot. Later gaskets were improved so be sure to look into that when purchasing.
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