"There she dribbles...."

[old DKP driver]

C’mon Steve,
Your case haves will never fret. You don’t drive your Bus enough for that to
Happen
Good thread though cuz them newbies gotta learn a thing or three !!!
But throw the sealer in the garbage after one year After opening as it
Will not retain All the good smelly ingredients it once had.
Chris
_________________
V.W.owner since 1967

[SGKent]

[ivwshane]

So what’s the consequences of an engine that leaks at the seam? Will it get worse? How long can one run their engine like this if you make sure your oil level is maintained?
_________________
77 westy 2.0 FI
69 ghia coup 1600dp
70 single cab

[SGKent]

[orwell84]

If you drive it to work, you can’t park in the same space everyday.

[ivwshane]

[SGKent]

Ok everyone - it is assembly time. Going to use Loctite 574 on the case. Need some help thinking this thru from anyone who has used this stuff on VW or Porsche engines.

One of the leaks on the last engine was the OUTSIDE of the main seal. Oil would eventually run down the case part line around the outside of the seal at 12:00 and 6:00. I tried to replace the seal and put some Curil-T in there but it would not adhere properly one oil was on the area. Cleaning with acetone etc., just washed more sealant out of the part area so the dribble remained.

I am trying to decide what to put in this area where the case halves and seal come together. Should I just put primer on the seal at 12 / 6 and let the 574 harden there (if it even will). Put some Loctite 518 there with primer? Loctite 565 and primer? Transition to Curil-T, Curil-K? Aviation sealer? 100% sure oil was running along that seam with the oil seal on the other case. I wonder these days if that has been the source of many oil leaks at the main seal over the years but I always assumed it was at inner lip and not the outer seal. Going to use the SABO seal or a factory seal a friend sent that he found (but it is 20 - 30 years old so I don't trust it as much as a new SABO seal).

Also - does anyone know if the factory installed the seals as the case was being assembled, or if they put them in after the case was assembled? Putting the seal in afterwards would wipe sealant away whereas putting the seals in as the case is assembled would trap the sealant and make a better seal. I do know that when Colin put in a new main seal on his case the proper tool had trouble keeping it square it was so tight. I think we actually ruined one VR seal trying to put it in with the tool.

_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[SGKent]

this is an add on to the last post.

The white arrow is the direction the oil flows. The red arrow is where it emerges.

It wicks around from behind the seal thru capillary pressure, along the part line and out. The last post is the question how to stop it. One cannot just load the seal up with sealer because the seal will spin and come loose, makes it too slippery. I am thinking a little Curil-T or Aviation Permatex along in that area at the back the seal pushes into when it is installed, or a little along that 12/6 line and put the seal in as the case is assembled. There is also 3-m weather strip available and Curil-K2. It has to be something impervious to oil and the chemicals in it. The case will be joined with Loctite 574. Can't plug the shim drain either. Loctite 518 is available too.

_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[udidwht]

That is mine with roughly 80K on the bottom end since complete rebuild back in early 2000. Pulled the heads at ~50K for new AA birals and re-worked AMC heads from headflowMasters in early 2012.

While I had it out I replaced the oil pressure switch, push rod tube seals, Frt. & rear seals, oil filter flange seal. I've put 30k since then. That pic was right after I did the CV boots/joints (Rockford boots).
_________________
1972 Westy Hardtop/Type-4 2056cc
96mm Biral AA P/C's~7.8:1CR
Headflow Masters New AMC 42x36mm heads w/Porsche swivel adjusters
71mm Stroke
73 Web Cam w/Web solids
Dual 40mm IDF Webers - LM-2 - 47.5 idles/125 mains/190 air corr./F11 tubes/28mm Vents - Float height 10.45mm/Drop 32mm
Bosch SVDA w/Pertronix module (7.5 initial 28 total @ 3400rpm)
Bosch W8CC plugs
Pertronix Flamethrower 40K coil
S&S 4-1 w/Walker QP 17862
3 rib 002 Trans
185R14 Hankook tires

[SGKent]

[SGKent]

well, it is time to work on it. I will use Loctite 574 on the case and 518 where the seal goes. Hopefully that will work.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[udidwht]

Permatex Aviation on the crankcase. Push rod tubes get viton seals with a smear of thread sealant on the tube grooves. Valve covers get a smear of Hylomar blue on the cover side of the gasket.
_________________
1972 Westy Hardtop/Type-4 2056cc
96mm Biral AA P/C's~7.8:1CR
Headflow Masters New AMC 42x36mm heads w/Porsche swivel adjusters
71mm Stroke
73 Web Cam w/Web solids
Dual 40mm IDF Webers - LM-2 - 47.5 idles/125 mains/190 air corr./F11 tubes/28mm Vents - Float height 10.45mm/Drop 32mm
Bosch SVDA w/Pertronix module (7.5 initial 28 total @ 3400rpm)
Bosch W8CC plugs
Pertronix Flamethrower 40K coil
S&S 4-1 w/Walker QP 17862
3 rib 002 Trans
185R14 Hankook tires

[SGKent]

[Good Old Dusty]

This is a very informative forum. I too have been chasing oil leaks on my 1978 Type 4 GE case. I am using aluminum cylinders, so I expect there will be slightly more expansion and contraction movement affecting the head bolts than there would be with the stock iron cylinders.

My current target is the lower four head to case M10 bolts. I have sealed around the washers to the aluminum head and between the nut and the washers with Curil T. I am still getting a small amount of leakage. It may be that I need to use a thread sealant on the nut. I am hesitant to use Loctite 565 in this location since it is effectively inside the engine.
I don't see any reference to sealant at this location in Scott or Steve's recommendations. Is Loctite 574 effective as a thread sealant? Can you please comment on this.

[secretsubmariner]

[raygreenwood]

I have kind of stayed out of this excellent thread....because as others have noted in similar threads....there are several including a long running one in the performance forums.......that its not so much about WHICH sealant you use....its how you use in in most places.

On finely machine, "0" tolerance joints case halves....you need whatever pliable, oil resistant sealant you like...applied EXTREMELY THIN and uniform.

Virtually any sealer with fairly high solids content will load up hydraulically as you squeeze the case halves together......and cause a thickness stack up. That means that a whole lot of it WILL squeeze outward...and inward...as you bolt it together.

And, just like any hydraulic force....it WILL hold the case halves apart by some small amount....always. They cannot be great for main and cam bearing tolerances.

So....its all in how you apply it.

I like the film strength, durometer and oil resistance of the Permatex ultra series. But...bluntly put....they are VERY high solids. They will have virtually n shrinkage as they cure ...so you MUST put them on very thin. Less than 0.001" if you really want them to stay put and not squeeze into the case.

A few years back...someone here did a "squeeze" test with RTV between two pieces of metal.

I did my own many years ago....between two pieces of Mic-6 aluminum...which are highly machined and very flat. I did this when I was first taught how to finger stipple RTV as uniformly as possible on case lines.

That was a very uniform method....but with a lot of case parting line....you have to get good and fast at it. Typically with that method you have "meringue" peaks about .003" high....with valleys in between that are about 0.0005" high. This gives room for the peaks to compress into the valleys and works very well.

But...unless you wipe away about 1/16" to 1/8th" of teh RTV on the inner side of the joint...you can still get a every small amount of RTV that squeezes inward.

Years later...watching other types of assembly my industry using adhesives....I started using the roll on method which delivers consistent application thickness of at or less than 0.0005". No propping apart of the case...no leaks. I won't bore you with the details here...but you can read about it in this thread

https://www.thesamba.com/vw/forum/viewtopic.php?p=8634655#8634655

All of that said.....yes.....Indian head gasket shellac is VERY GOOD.....but understand. Its a medium solids, alcohol based sealant...about 55-60%. The rest is ethanol, Methanol, Isopropanol and MIBK. It evaporates and starts setting FAST.

It also cures hard. While it has some flexibility when its a thin film....it also should not really be attached to thigs that flex a lot...like the front or rear main seal. While its a good adhesive to keep those two seals from squeezing out, the flexibility of those seals will eventually cause the Indian head to leak.

And...Indian head is damn hard to get off. It really works well on gasket joints like for transmissions. It works decent on case halves....but if your engine gets beat on or you have significant case fretting....it can seep oil.

It is very oil and fuel resistant. It works very well for adhering oil cooler seals....to one side only. Either seal them to the case (which I think is a mess) or seal them to the oil cooler. In this way....it does not have leakage flexing issues as much as it would if you sealed both sides.

The medium solids loading means that if you can spread Indian head on thin...about .001" to .0015"...it will shrink up as it dries to about half its thickness making a very good case joint overall.

The other types of sealants that skills noted....Hondabond....Yamabond etc.....are also excellent.

They are mostly similar in "operation" to Indian Head...in that they have a low to medium solids content that crosslinks into a very oil/fuel resistant film....that are carried in a binder/vehicle solvent that evaporates away.

I have recently gotten back into using Permatex "Motoseal". It has right at 45-50% solids. But...unlike Indian head...it dries into a FLEXIBLE...very fuel/oil resistant film with moderate adhesive properties. Its very easy to make into a thin film when wet that flows out well and dries to a film thickness roughly half of what it was wet.

Its texture and elasticity/stretch....and its finished appearance....is very similar to Permatex Ultra Gray.....except that its probably 25% softer more pliable....more like Permatex Ultra copper.


As for the case joint line leakage point on the front main seal......this is because the joint mating edge can never be perfect as you get heat expansion. One side will always protrude further...even if its only a few 10 thousandths. This creates a valley for the oil to bypass through if you get any kind of case pressure at all.

What you can do to fix this....is to take a fine diamond file or oil stone...and bevel both sides of the case wall to make a triangular valley in the location where that case parting line is. It only needs to be about 0.010" deep/wide. Then fill that triangular valley with a high solids RTV like Permatex ultra gray. Let it cure fully before installing the seal.

That forms a flexible "fillet" that moves with the expansion of the case.

Of course...also make sure that you are using the correct seal thickness in the correct seal bore. There are cases out there with 12mm bores that use the Vanagon seal. I have no idea why. Ray

[Good Old Dusty]

Ray. Thanks for your extensive response to my question. Great photos in the link. I would appreciate your thoughts on the correct sealant to use on the washers and threads of the 4 lower M10 bolts holding the heads on. These locations are inside the lubrication system and subject to head and cylinder expansion and contraction. So far Curil T is not working perfectly for me. Perhaps I should try Loctite 574. Any thoughts on the sealant for this location? ...Thanks... Don

[raygreenwood]

[raygreenwood]

So...thinking about your last question....the lower four cylinder studs.....over the eons....I see experiences (my own and observations of others) of leakage from these four studs from inside teh rocker box ...fall into two main categories and a thin gray area in the middle:

1. Either people get significant leakage and it drives them nuts....and usually its more than just a sealer issue in this category.

2. They have no issues at all...with or without sealer

3....the gray area...is engines that have some sweating of oil from all of these studs but not enough that anyone gives it a second thought....either because they never inspect or notice or they are slobs and do not care

Not to overthink this....but then again thinking about it is free.....

If these studs are going to leak.....other than loosening issues....they are going to leak from three places. Might be from just one or all.

A. Leaking down through the threads between the nut and stud. I think this is the least problem. And...if you are getting leakage through the threads...either the thread fit sucks or the whole stack up is flexing (either from torque or from heat cycling) and causing the thread lands in certain areas to come out of contact with each other. I mean...you have to have a gap for oil to move through right?

This can be fixed by using something like loctite and really you should be using new nuts with a tight thread fit. I would not put heavy sealer like RTV on the threads because it will affect the torque.

B. leaking between the nut and washer. First...make damn sure you are using a forged washer. And....make it as flat and smooth as possible if its overly crowned on the nut side. Use a file or sandpaper

The gist is that between the crown of the washer and or teh surface of the nut...you can have fine gaps that the oil can flow through and onto and down the head stud.

And when you put the nut on.....use a small, thin amount of DRYING sealer between the nut and washer. Meaning...something strong, oil proof, flexible...that cures completely. Not Curil T.
Torque it. Let it dry completely. A lot will squeeze out. Some will remain to level and fill any gaps.....BUT....then.....paint or smear on a thin coat of the same sealant around the outside of the joint right where the nut meets the washer. Keep it very thin so it will not be prone to dislodge and get into the oil. Its basically sealing from the inside and out.

C. Leakage between the washer and the head....very common. Most common. The texture of heads where the washers fit after many rebuilds and bead blasting and washers that have turned and gouged out metal....is rough. It leaves lots of oil leakage gaps under the forged washer.

I have seen engine builders building very high end aluminum head water cooled engines....who use various methods to smooth and flatten the areas where the forged washers will sit. This is mainly to make sure the washer has nothing it can crush down and loosen from.

The most common is a simple tool that is a washer on a mandrel with sandpaper applied to the face. Others use the same with scotch brite.

The most common sealer(s) I have seen on engines I tear down over the decades...to keep from leaking at this joint.....are Indian head or aviation form a gasket #2.

Its common to take the washers...spread a thin coat on one side....apply to the head and press down to squeeze out a small amount of excess. This fills the uneven or rough surface. let it dry completely before putting on the nut and torqueing it.

You could use Motoseal, Hylomar or Hondabond for this in the same way. Still teh object is let it dry before you torque it down.

I have seen RTV work too....but its risky because its flexible and high solids. It loads up to a thickness...that will sooner or later crush down and release some torque on the nut. Don't use RTV for that.

So .....you are looking for a fuel proof, completely hardening sealant...that still has some flexibility.


I typically adhere the washer to the head and let dry as mentioned. Then smear the washer with it....apply thread locker to the threads only...very sparingly....then apply the nut and torque. Let all of that dry and then smear the joint between washer and nut with the same sealant and let dry.

Ray

[SGKent]

used threebond on the case, and a tiny amount of Loctite 574 on the web where the bolts pass thru. Curil T on the 10mm case bolts and Nuts. Used PTFE thread sealant on the 8mm washers and nuts. I can tell from watching the three bond that it will take a jackhammer if I ever want to take that case apart again.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin