Oil leak at the head?

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jseng1 said:
texasSlick said:
Review Jim Schmidt's leak fix:

sealer-for-copper-head-gaskets-t26022.html?hilit=Oil%20leak%20wire#p344282

Slick
Click to expand...

I haven't found a better high temp HG sealer than Pliobond. The trick is to coat each surface - the head, the cylinders, and both sides of the copper gasket (with the .005" copper wire around the pushrod tunnels and oil return hole). When you let it semi dry it becomes bonded to each metal surface so oil can't weep through. You can't half-ass it and skip coating a surface or it might leak. You don't have to worry about evenness of the sealer. Any extra sealer squishes out and flattens to nothing.

I'm having no leaks at all and it doesn't seem to matter if I use waisted (triangulated) bolt shanks or not - I'm not seeing leaks either way. It may be that the waisted head bolts are more important on larger displacement motors that want to blow the head off - I haven't determined that one way or the other.
Click to expand...

Jim,

Is the Pliobond you speak of a contact adhesive? Is it this stuff: http://www.micro-tools.de/en/Adhesives- ... ottle.html

Kevin
 
click said:
jseng1 said:
texasSlick said:
Review Jim Schmidt's leak fix:

sealer-for-copper-head-gaskets-t26022.html?hilit=Oil%20leak%20wire#p344282

Slick
Click to expand...

I haven't found a better high temp HG sealer than Pliobond. The trick is to coat each surface - the head, the cylinders, and both sides of the copper gasket (with the .005" copper wire around the pushrod tunnels and oil return hole). When you let it semi dry it becomes bonded to each metal surface so oil can't weep through. You can't half-ass it and skip coating a surface or it might leak. You don't have to worry about evenness of the sealer. Any extra sealer squishes out and flattens to nothing.

I'm having no leaks at all and it doesn't seem to matter if I use waisted (triangulated) bolt shanks or not - I'm not seeing leaks either way. It may be that the waisted head bolts are more important on larger displacement motors that want to blow the head off - I haven't determined that one way or the other.
Click to expand...

Jim,

Is the Pliobond you speak of a contact adhesive? Is it this stuff: http://www.micro-tools.de/en/Adhesives- ... ottle.html

Kevin
Click to expand...

I'd say its the same stuff. Pliobond 20 and 25 are the same but with different solvents and that should not matter. It depends what size the container is. I've only tested the 20 & 25
 
Thanks Jim, I had visions of glueing my cylinder head together & not being able to ever remove it :shock:
 
click said:
Thanks Jim, I had visions of glueing my cylinder head together & not being able to ever remove it :shock:
Click to expand...

Doesn't happen. Pops right off when you loosen the head bolts because of pushrod/valve spring pressure (a couple valves are always slightly open).
 
Well I have lapped the head on a sheet of glass. It is all now a light gray color. Got 2 new composite gaskets. Going to chase the threads in the cylinder block to make sure there isn't anything in there to give me a false torque reading.
Thinking I might put a smear of copper coat around the push rod tunnels, what do you think?

Should be running by the end of the week.

John in Texas
 
N0rt0nelectr@ said:
Well I have lapped the head on a sheet of glass. It is all now a light gray color. Got 2 new composite gaskets. Going to chase the threads in the cylinder block to make sure there isn't anything in there to give me a false torque reading.
Thinking I might put a smear of copper coat around the push rod tunnels, what do you think?

Should be running by the end of the week.

John in Texas
Click to expand...

If you're using AN composite gaskets and you have flat surfaces then all you need is scrupulously clean and dry surfaces and it will seal perfectly PROVIDED you follow the ridiculous sounding, but necessary, torquing procedure.
 
Fast Eddie said:
If you're using AN composite gaskets and you have flat surfaces then all you need is scrupulously clean and dry surfaces and it will seal perfectly PROVIDED you follow the ridiculous sounding, but necessary, torquing procedure.
Click to expand...

I can't think of a better time to give your advice a shot...
Since I recently blew my copper head gasket, I figured that I would try a composite this time.
Oil leak at the head?


Oil leak at the head?


.I checked, checked and re-checked the mating surfaces for flatness and everything showed surprisingly true.
.I obsessively cleaned the mating surfaces, bolt holes, stud threads, etc...
.I'm using a new Victor Reinz .075 gasket - DRY
.Last night, I Installed and torqued the head down according to the sequence and specs. in the shop manual.
.This morning, Loosened and re-torqued the fasteners.
(****All except for the nut under the intake manifold. I'm using my old ground down 9/16" wrench and have no idea what the torque on that nut is.***)

I've got the top motor mount and exhaust mounted now, I hope to have it buttoned up and running this afternoon.
 
There are slight variations on the theme, but most re-torquing procedures that folk do seem to go something like this:

1 torque it up

2 run it for a short while without riding it, leave overnight and torque

3 torque at 50 miles

4 torque at 100 miles

5 torque at 200 miles

6 torque at 500 miles


First time I did this I thought it must be bullshit. But the amount the fasteners lost torque amazed me. I was actually beginning to think my stainless ARP fasteners were stretching or something!

But at 500 miles there was no discernible loss of torque and that's how it seemed to stay.
 
Well I have found the problem. The stud hole had broken through the push rod tunnel on the right side. Now I have to figure out the best way to fix it.
I have an email in to Jim Comstock but I thought I would ask you too.
First I am going to pull the cylinders and remove the lifters so I don't drop anything on to the lifters and cam.
I'm thinking the best way to fix this is to put the stud back in with Locktite and then JB Weld the hole. Let it dry for a few days and then sand the JB Weld smooth. Anything you can see wrong with my plan?
Here is a picture of what I found. I shined a flashlight down the stud hole and you can see the 1/4" hole in the tunnel.

John in Texas
 

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N0rt0nelectr@ said:
Well I have found the problem. The stud hole had broken through the push rod tunnel on the right side. Now I have to figure out the best way to fix it.
I have an email in to Jim Comstock but I thought I would ask you too.
First I am going to pull the cylinders and remove the lifters so I don't drop anything on to the lifters and cam.
I'm thinking the best way to fix this is to put the stud back in with Locktite and then JB Weld the hole. Let it dry for a few days and then sand the JB Weld smooth. Anything you can see wrong with my plan?
Here is a picture of what I found. I shined a flashlight down the stud hole and you can see the 1/4" hole in the tunnel.

John in Texas
Click to expand...

Wow, good find John!

I'm gonna show my uncouthness now...

I would clean out the hole (and stud) as thoroughly as I could, using brake cleaner spray etc. Then force some JB weld into the hole, then fit the stud straight away and use it to "hydraulically" force the JB weld through the hole into the pushrod tunnel, where it could just be wiped off and smoothed over. If you lubricate the stud first, you should even be able to remove it without disturbing the 'fix'.

Or you could probably achieve the same using high temp silicone instead of JB weld (but without the part about oiling the thread etc).
 
I remember there being a thread repair kit that was a 2 part epoxy but it came with a releasing agent for the threads. Think it was made by Permatex?
Have to go online and look. Good idea!

Thanks
John in Texas
 
I have always had good luck with Permatex thread sealant. It holds up to heat and does a good job sealing, it's also easy to disassemble. I have never tried it in this particular situation though.
Pete
 
I just got an email from Jim and he says the problem is common. I don't know how common it is but in the 40+ years I have been riding Norton's this is a first for me. He said to use red Loctite on the stud and that should solve the problem. I will do that shortly and let it set up overnight.
Keep you all posted.

I would like to thank all of you for your thoughts and ideas.
We are fortunate to have someone like Jim to turn to when we have a head scratcher like this.
Thank you Jim.

John in Texas
 
Well it's back to the drawing board for me. I did as Jim suggested and used Loctite on the studs in the cylinders, started it up and it still leaks.
I did let is set up overnight before reassembling everything. I have extra cylinders so I guess that's the way to go.
I will dig them out and mic them to see what size pistons I will need and go from there. Just when I think I have things sorted out the wheels fall off the project. Such is life with older British bikes.

John in Texas
 
N0rt0nelectr@ said:
Well it's back to the drawing board for me. I did as Jim suggested and used Loctite on the studs in the cylinders, started it up and it still leaks.
I did let is set up overnight before reassembling everything. I have extra cylinders so I guess that's the way to go.
I will dig them out and mic them to see what size pistons I will need and go from there. Just when I think I have things sorted out the wheels fall off the project. Such is life with older British bikes.

John in Texas
Click to expand...

Bad luck John.

I still reckon the JB weld should work, if it's 'hydrauliced in' as discussed earlier...
 
N0rt0nelectr@ said:
Well it's back to the drawing board for me. I did as Jim suggested and used Loctite on the studs in the cylinders, started it up and it still leaks.
I did let is set up overnight before reassembling everything.

John in Texas
Click to expand...

Did you de-grease both the female and male threads scrupulously before applying Locktite? Both red and blue are oil resistant after cure, but likely to fail if applied over oily threads.

Slick
 
N0rt0nelectr@ said:
Well I have found the problem. The stud hole had broken through the push rod tunnel on the right side. Now I have to figure out the best way to fix it.
I have an email in to Jim Comstock but I thought I would ask you too.
First I am going to pull the cylinders and remove the lifters so I don't drop anything on to the lifters and cam.
I'm thinking the best way to fix this is to put the stud back in with Locktite and then JB Weld the hole. Let it dry for a few days and then sand the JB Weld smooth. Anything you can see wrong with my plan?
Here is a picture of what I found. I shined a flashlight down the stud hole and you can see the 1/4" hole in the tunnel.

John in Texas
Click to expand...

John, I think it is common, which means I have one the same! I see the loctite on its own didn't work for you, but it might if you are scrupulous with the degreasing.

However, I did exactly what you proposed here, loctite on the threads, JB weld over the hole/exposed thread. It coped with 24 races in 2015!

It may have leaked a little towards the end, but that is with a copper head gasket that got nipped upa few times, and I admit I was more concerned about head gasket integrity than oil drips....racers eh!

Steve
 
ARP thread sealer does an amazing job of sealing up oil leaks thru studs.
Will even work when some oil is present.

Glen
 
SteveA said:
N0rt0nelectr@ said:
Well I have found the problem. The stud hole had broken through the push rod tunnel on the right side. Now I have to figure out the best way to fix it.
I have an email in to Jim Comstock but I thought I would ask you too.
First I am going to pull the cylinders and remove the lifters so I don't drop anything on to the lifters and cam.
I'm thinking the best way to fix this is to put the stud back in with Locktite and then JB Weld the hole. Let it dry for a few days and then sand the JB Weld smooth. Anything you can see wrong with my plan?
Here is a picture of what I found. I shined a flashlight down the stud hole and you can see the 1/4" hole in the tunnel.

John in Texas
Click to expand...

John, I think it is common, which means I have one the same! I see the loctite on its own didn't work for you, but it might if you are scrupulous with the degreasing.

However, I did exactly what you proposed here, loctite on the threads, JB weld over the hole/exposed thread. It coped with 24 races in 2015!

It may have leaked a little towards the end, but that is with a copper head gasket that got nipped upa few times, and I admit I was more concerned about head gasket integrity than oil drips....racers eh!

Steve
Click to expand...
Well I found my own stupid mistake. I used the wrong grade of Loctite. I had a Loctite Quickstick 548 that a friend had given me and it is a non-hardening compound. I should have read the label a lot closer. Time to pull it down again and do it right this time.
John in Texas
 
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