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Sat Nov 05, 2022 12:13 pm

My first stroker that i got from someone else ruined a crank and rod bearings/journals cause someone used sealant there and the just a little sealant came out and plugged a oil passage. Is it really worth it?

Seems like trying to seal a problem that doesn't exist.

Sat Nov 05, 2022 12:24 pm

txoval wrote: 1184 is very thin…flows like paint Thanks

Sat Nov 05, 2022 12:59 pm

chrisflstf wrote: Ray greenwood has posted on how to roll out rtv really super thin. I assume for a case its only applied on 1 side, since we have studs on the other half. Not easy to use a roller around studs, but maybe there is a work around for that

I did a similar method. I applied it to both halves. Not a problem because I always remove all the studs. You have to remove them to stone the case halves anyways.

Sat Nov 05, 2022 2:03 pm

Vanapplebomb wrote: chrisflstf wrote: Ray greenwood has posted on how to roll out rtv really super thin. I assume for a case its only applied on 1 side, since we have studs on the other half. Not easy to use a roller around studs, but maybe there is a work around for that

I did a similar method. I applied it to both halves. Not a problem because I always remove all the studs. You have to remove them to stone the case halves anyways.
I liked Ray's RTV roller application method. Masterfully done!

Here is where it would be a problem. A shuffle pinned case.
Sure you can remove the case studs. But the shuffle pins would be a challenge to remove without damaging them.

Sat Nov 05, 2022 2:12 pm

Pretty easy with a collet style dowel pin pulled. The shuffle pins are not pressed in hard at all. Best that they have to come out anyways to dress the case.

Sat Nov 05, 2022 2:35 pm

mrmarcdude wrote: Hey i was wondering what you guys reccomend to seal the two case halfs? Any feedback on a specific product? What to stay away from? Thanks a lot guys

Glenn wrote: Permatex Aviation will work. Never ever use any silicone form-a-gasket.

The last engine I assembled was in January 2017; I used Permatex Aviation, shows in this photo

Sat Nov 05, 2022 2:41 pm

Vanapplebomb wrote: Pretty easy with a collet style dowel pin puller. The shuffle pins are not pressed in hard at all. Best that they have to come out anyways to dress the case.

Absolutely, a collet styled puller is the easiest way.

Sat Nov 05, 2022 6:45 pm

Anybody read this?
https://dm.henkel-dam.com/is/content/henkel/Gasketing%20Design%20Guide-Final_LR

Sun Nov 06, 2022 1:49 pm

jpaull wrote: My first stroker that i got from someone else ruined a crank and rod bearings/journals cause someone used sealant there and the just a little sealant came out and plugged a oil passage. Is it really worth it?

Seems like trying to seal a problem that doesn't exist.

Any Loctite 574 not enclosed in a flange will not harden and is designed to be flushed away by engine oil on the first engine start, then out of the engine totally on it's first engine oil change. Any silicone sealant can stick clog and kill brand new engines, another reason I guess Porsche chose Loctite574 as one of their case flange sealants.

Sun Nov 06, 2022 4:52 pm

What type of sealant did the Factory use?

Maybe someone ask Ray greenwood what is the best, lol He does have alot of good tech advice

I read the Henkel manual, mostly, need to reread again

What does Modok say?

Found this also:
https://www.amazon.com/Permatex-85420-Permashield-Resistant-Dressing/dp/B007VIGCJW?th=1

Sun Nov 06, 2022 5:55 pm

Only somewhat relevant to case sealing.... Project Farm on YT recently did a silicone sealant comparison test. I had discovered Mopar black back in the mid 80s when I worked at a Dodge dealer. In the PF tests it came in a close second iirc and first when cost was factored in. I would not use it between the case halfs but will use it at the cyl bases and other areas where silicone sealant is appropriate

Sun Nov 06, 2022 6:52 pm

On the type-1 whatever it was, it allowed the case halves to come together all the way.

I "think" it was a non-hardeneing sealant, or at least THAT kind of sealant suits the design best.
Keep in mind every little thing the factory did was not always super smart, you know, they had great ideas and they had bad ideas. Like the sealing nuts that didn't work, what the heck, why not acorn nuts.... they had them on the oil plate LOL.

The type-4 is a bit different and so is a WBX, the late WBX bearings would be virtually fully seated right at assembly so maybe that one you would use the loctite acrilic anerobic sealant.

Not just VW but many kinds of engines that have a rear bearing cap and main seal as one piece and it has the same kind of issues and for sure the best design is just not to design it that way at all, make the seal holder separate.
That way the bearing cap can flex and move around all it wants it won't disturb the seal and the sealant won't disturb the bearing cap seating.

Ray Greenwood thin film method very neat way to do it but around the main seal and cam plug and the oil pump is just terrible design and it does not SOLVE the problem fully, still requires absolute precision fits to work that only the German designers would dare to THINK is possible.

But IMO silicone in a groove is actually a good solution to that type of problem. So PERSONALLY that's what I will be experimenting with as I get the opportunity. Like cutting a groove between the main seal and the cam plug groove, and the loctite manual does give some good hints and ideas on that including 30 degree ramp shape, actually 30 degree chamfer might make it work better with non hardeneing sealant too.
But that IS an experiment, so, I may change my mind in five years. Have before. One time thought it was smart to use different kinds of sealant on different parts of the case split, well.... didn't work out. So, no more of that.

Sun Nov 06, 2022 7:16 pm

rayjay wrote: Only somewhat relevant to case sealing.... Project Farm on YT recently did a silicone sealant comparison test.
YEAH that was very good especially how the % cured in deep gaps really varied.

Thu Jan 19, 2023 6:51 pm

In the past I used Curil K2 and it weeped a tiny bit after 2500 miles. I used Loctite 574 and it weeped a little too. This time I used Threebond 1184. It seems like a really solid sealer, and paints on well. I used a little Loctite 574 on the case webs where the six bolts come thru. The cases are always well prepped before applying sealer. Kuril is probably the easiest to clean up with a little acetone.

While Threebond 1184 is highly recommended, it is good from-40C to 150C (-40F to 302F) then it starts to slowly lose strength. That is about the max one should ever let the oil get to on its worst day just before the fried eggs burn :lol: :lol: :lol: I'll let everyone know how it goes. I've never found anything that didn't weep a little after awhile. Used to use Gasgacinch - the old formula and it was good for about 15,000 miles on my t1 engines.

Thu Jan 19, 2023 7:39 pm

Vanapplebomb wrote: At the time when I used 574 or 518 on the main saddles I did not use any sealant on the main bearing through bolts (type 4). I never cared for (and still don’t) trying to seal straight threads, bolt heads, washers, etc. Thread lockers work well for sealing straight threads, but I still don’t like trying to seal bolt heads, washers, etc.

As for the switch to RTV, I gave it a go several years back, and really liked it. It is transferred from glass to the case with an ink roller, super thin. I actually let it fully cure before assembly. I actually built up a motor with that technique, realized I forgot the cam plug, took it apart a week later, and reassembled with the cam plug. I never reapplied the sealant. The case halves don’t bond together because the RTV is fully cured before assembly, so you can separate them and slap them back together. How many times? I don’t know. I do know it can be done at least once because after 7 years, still no leaks anywhere.

Is there a link to Ray’s ink roller technique here somewhere?
Vaguely remember seeing this somewhere…. :-k

Sun Apr 30, 2023 3:40 pm

This is how I did it, I'll post an update if it runs... :lol:

Sun Apr 30, 2023 7:40 pm

Always brave to post a video.

Like Alstrup has said in previous posts…apply the sealant to the other case half without the studs sticking out…so much easier

That was also too much aviation…it will be on the bearings if you were to take the case apart, especially the flywheel side cam bearing. I’ve seen it first hand

Also, please don’t rotate your crank like that and have the rod smack the cylinder openings…I promise you there are dings in the sealing surface now

Wed Aug 02, 2023 10:01 am

Just found this helpful thread, thanx you Sir .

Wed Aug 02, 2023 10:43 am

Clatter wrote: Vanapplebomb wrote: At the time when I used 574 or 518 on the main saddles I did not use any sealant on the main bearing through bolts (type 4). I never cared for (and still don’t) trying to seal straight threads, bolt heads, washers, etc. Thread lockers work well for sealing straight threads, but I still don’t like trying to seal bolt heads, washers, etc.

As for the switch to RTV, I gave it a go several years back, and really liked it. It is transferred from glass to the case with an ink roller, super thin. I actually let it fully cure before assembly. I actually built up a motor with that technique, realized I forgot the cam plug, took it apart a week later, and reassembled with the cam plug. I never reapplied the sealant. The case halves don’t bond together because the RTV is fully cured before assembly, so you can separate them and slap them back together. How many times? I don’t know. I do know it can be done at least once because after 7 years, still no leaks anywhere.

Is there a link to Ray’s ink roller technique here somewhere?
Vaguely remember seeing this somewhere…. :-k

Sorry I did not see this 7 months ago....

https://www.thesamba.com/vw/forum/viewtopic.php?t=...highlight=

By the way, I did not invent this method. I have used it and it is spec'd....or versions of it...for a wide range of industrial equipment sealing in factories I have been in and out of for years.

When dealing with machined surface or flange seals, engineers have known for eons that they operate best when the sealant or adhesive is as thin as possible.

We are not talking about "gasket maker" here or large gap filling. That is a different animal. We are talking about sealing a pair of mated machined surfaces.

All you should be filling with this type of seal are shallow machine marks and fine dents, scratches or imperfections that cannot be removed.

A sealing film like this is a single homogenous layer.....until it gets too thick. Then it should be thought of or visualized as THREE distinct layers....even though its one distinct complete layer of adhesive/RTV.

The two outside layers are where the adhesive/RTV is against the metal surfaces that the adhesive or RTV is attached to (in our application its each side of the engine case).

If the surfaces are very clean and the adhesive/RTV was applied carefully and uniformly....those outer "layers" are pretty bulletproof. They will not seperate from each other. The adhesive/RTV is now essentially a metal backed elastomer layer.

Once its cured....if its thin enough....its very hard to discern where the outer metal backed layers end and the middle layer begins. This is when adhesive and RTV are at their strongest....film strength wise.

When the RTV film gets too thick.... the third layer....the inner thickness of RTV between the two "metal backed" outer layers will have a totally different hardness or durometer.

It is also free to FLEX. its UNSUPPORTED.

Depending on the hardness or durometer of the RTV or adhesive....you need to keep it down under about 0.0005" to 0.001" maximum layer thickness or the RTV layer can tear through the middle third layer and leak.

If you are going to use actual RTV...I recommend the roller method. Each RTV type has a different viscosity and shear point. The roller will shear it down to the minimum film thickness the RTV can produce. And, softer rollers make a thicker film and harder rollers make a thinner film.

Many years ago I had used only a few times on other peoples equipment...sealants like Yamabond (solvent based). I did not like them back then only because they were a mess, dried too quickly etc.

I have kind of rediscovered that sealant type over the past two years. I like the Permatex Motoseal for sealing machined joints. Its also fuel and oil proof.

If you understand why making RTV 0.0005" thick makes a better seal and thats what you are trying to do....solvent based sealants like Motoseal and Yamabond can help do that easier.

They are essentially a solvent based RTV. They are about 60% solvent. So if you can spread them on or even roll them on...right at 0.001"....once the solvent flashes off they will be right around 0.0004" to 0.0005" thick. Ray

Wed Aug 02, 2023 11:21 am

YAY! Another Motoseal fan! I've been preaching thaat gospel for about 12 years now... :)