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PITApan
Samba Member
Joined: November 09, 2014
Posts: 1058
Location: Northern Colorado
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 Posted: Mon Dec 22, 2014 1:18 pm Post subject: |
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| SGKent wrote: |
| raygreenwood wrote: |
I'm not sure what you are referring to.... with regard to what I posted. But that is nice to know. Thank you.
What I was implying in that post.....is that in this seal stack up...there is no need for RTV on either the case side or the outer lid side. I am not gluing the gaskets to either the case or the lid.
in this manner the strainer, comes out flean wach time and allows a slight spin of the gasket/strainer stackup each time so that the RTV or gasket face does not get abraded or torn. This stackup has lasted an easy 100k miles more than once with no leaks.
You, could use an, adhesive for the gasket and strainer assembly just as easily. I use the RTav and make note not to put pressure on the stack and squeeze out what little RTV is between the gaskets and strainer until it, dries...because that extra little squeezability of the Ratav helps to seal the stack and keep tensioj on it considering how little torque it uses. |
I was just clarifying that RTV is used on the cylinder barrels to case. Other than that I am not aware of it being used anywhere else on the engine unless the anaerobic Loctite used in lieu of an oil pump gasket could be counted. I concur that none is used on the strainer cover. |
There are many games you can play with it. You can seal rocker covers so they won't so much as weep, pop off easily and last many, many years. Details @ 11 |
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SGKent 
Samba Member
Joined: October 30, 2007
Posts: 41031
Location: Citrus Heights CA (Near Sacramento)
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| Posted: Mon Dec 22, 2014 1:29 pm Post subject: |
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| PITApan wrote: |
| There are many games you can play with it. You can seal rocker covers so they won't so much as weep, pop off easily and last many, many years. Details @ 11 |
no - no. They don't weep if they are flat. Usually someone used sealer and they are so hard to get off they twist, then one gets a perpetual leak.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin |
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PITApan
Samba Member
Joined: November 09, 2014
Posts: 1058
Location: Northern Colorado
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| Posted: Mon Dec 22, 2014 6:10 pm Post subject: |
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| SGKent wrote: |
| PITApan wrote: |
| There are many games you can play with it. You can seal rocker covers so they won't so much as weep, pop off easily and last many, many years. Details @ 11 |
no - no. They don't weep if they are flat. Usually someone used sealer and they are so hard to get off they twist, then one gets a perpetual leak. |
I dissagree---I think. I've always had them at least weep and sometimes leak. But I can't vouch for the flatness of that tin cover, never mind the head. Keeping them fresh helps. Using sealer is a one shot deal---unwise in general. That said, I've been using Great White as a thread sealant on threaded fuel fittings (I found out it's proof against almost everything) and it might be something to try. You can wipe it off if you don't like it and a thin film should not (edit--oops) get in the oil.
Using silicone as a molding compound rather than a sealer is extremely effective. It takes up any out-of-float conditions. Part of the technique has been mentioned. In brief:
1) Use the right stuff. The Gray is the ghighest durometer and usually the most desirable. The red and blue are rather fragile.
2) Control adhesion. Where you want it to stick use the most complete prep, Like an air eraser on rocker covers. Where you don't want it to stick a thin film of Vaseline or silicone grease works well.
3) Use molding technique. Apply thickly enough to fill the gap+, clamp very lightly to insure complete contact with all surfaces, let it dry overnight or more, esp. in the cold. Read the tube.
4) Disassemble and trim any extra. Any squeeze out will break off and get in your oil or worse. Trivial on the outside but make a neat job of it anyway.
5) Wipe away any resist so it doesn't cook on. This is an advantage of using silicone grease for your resist. You want some for your wiring anyway.
6) do final assembly under full pressure.
I would not do a full silicone gasket instead of the cork gasket for rocker covers. The cork spaces the cover out and provides tension to the wire bail. So you can either work the silicone over the cork (might stick poorly) or you can punch small circles out of the cork to use as spacers, maybe a half dozen /cover, and bury them in the silicone.
Never switch covers around. They are molded exactly to the head.
I'll be making up a set of these and I'll try to get some pics of the sequence. |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21513
Location: Oklahoma City
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| Posted: Mon Dec 22, 2014 9:29 pm Post subject: |
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| PITApan wrote: |
| SGKent wrote: |
| PITApan wrote: |
| There are many games you can play with it. You can seal rocker covers so they won't so much as weep, pop off easily and last many, many years. Details @ 11 |
no - no. They don't weep if they are flat. Usually someone used sealer and they are so hard to get off they twist, then one gets a perpetual leak. |
I dissagree---I think. I've always had them at least weep and sometimes leak. But I can't vouch for the flatness of that tin cover, never mind the head. Keeping them fresh helps. Using sealer is a one shot deal---unwise in general. That said, I've been using Great White as a thread sealant on threaded fuel fittings (I found out it's proof against almost everything) and it might be something to try. You can wipe it off if you don't like it and a thin film should not (edit--oops) get in the oil.
Using silicone as a molding compound rather than a sealer is extremely effective. It takes up any out-of-float conditions. Part of the technique has been mentioned. In brief:
1) Use the right stuff. The Gray is the ghighest durometer and usually the most desirable. The red and blue are rather fragile.
2) Control adhesion. Where you want it to stick use the most complete prep, Like an air eraser on rocker covers. Where you don't want it to stick a thin film of Vaseline or silicone grease works well.
3) Use molding technique. Apply thickly enough to fill the gap+, clamp very lightly to insure complete contact with all surfaces, let it dry overnight or more, esp. in the cold. Read the tube.
4) Disassemble and trim any extra. Any squeeze out will break off and get in your oil or worse. Trivial on the outside but make a neat job of it anyway.
5) Wipe away any resist so it doesn't cook on. This is an advantage of using silicone grease for your resist. You want some for your wiring anyway.
6) do final assembly under full pressure.
I would not do a full silicone gasket instead of the cork gasket for rocker covers. The cork spaces the cover out and provides tension to the wire bail. So you can either work the silicone over the cork (might stick poorly) or you can punch small circles out of the cork to use as spacers, maybe a half dozen /cover, and bury them in the silicone.
Never switch covers around. They are molded exactly to the head.
I'll be making up a set of these and I'll try to get some pics of the sequence. |
I fully agree.
There are other techniques (games as you note) as well for RTV...for instance for quality, machined surfaces that require no "leveling" (nice description of the issue by the way).....applying the RTV micro thin as a combination pore filler and adhesive works wonders. I have described the process and posted pictures recently.
As for the valve cover rail gasket, I use a medium coat...about 1 mil thick between gasket and valve cover only. I spread it on the gasket uniformly by stippling. ...no gooping things up.
I then clamp the assembly only partially either on a spare head (if you have the luxury) or on the engine....but best to dry overnight. During the initial drying the bail is on just enough to keep the gasket contacted to the valve cover EVENLY.....without squeezing any of the RTV out.
That means the bale is about 1/2" to 3/4" from the locking notch. Only a few pounds of pressure. When dry, pull the cover, check the inside for any holes or missing RTV....or any excess squeezed out to be removed. ....then oil the gasket fwce and lock it down.
To be clear..these do not migrate, suck In, weep or leak.
with lots of driving...usually at 30-40k miles even with regular valve adjustments....they will juuuust start to weep....signaling that the rubberized cork is no hard as a rock and has tlno elasticity to offer ro the tension of the bale. Time to change them.
Its REALLY easy to clean off. Peel up a corner and 9 out of 10 times the gasket comes off in one piece. The thin layer of RTV left...can be removed with a sinhle layer of gasket remover spray if you feel the need....but usually about a minute with, either a brass or black nylon wheel in a dremel takes it off clean as a whistle. A quick wipe with acetone, MEK or Berrymans and you are ready to apply new RTV and gasket.
I do two sets at a time. Keep one in a bag on the shelf. I just swap them and clean the used set at leisure.
The RTV's of today are light years different than back when VW was still building AC engines. In fact they are changing, dramatically every year.....in every industry. Just this week I am working with high modulus printable RTVs. Awesome stuff. I urge people to experiment. Ray |
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SGKent
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Joined: October 30, 2007
Posts: 41031
Location: Citrus Heights CA (Near Sacramento)
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| Posted: Tue Dec 23, 2014 9:15 am Post subject: |
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next time the covers are off and cleaned with a bead blaster so there is no gasket left on them, put them on the heads and see if they will rock. If they do try to get the rock out. Also my experience is that the cork gaskets are often on the shelves for a long time and they get hard. Combine that with a slight warp in the cover and they weep. It is almost impossible for one to weep when it is flat and on securely.
Further, if one looks at the end of a cover on a T4 engine they will see a cutout and flare. That flare is to help take them off. Many mechanics pry on the corner which warps them. Think of a sheet of plywood lying on the ground. If you pick a corner up the whole sheet twists. That is what causes them to leak. Also - next time you get a cork gasket for one, squeeze them between your first finger and thumb nail. You can tell if the gasket is old or new by how easy it is to squeeze. The easier it is to squeeze, the more warp it will protect against. The hard ones won't seal up with warp. It took me a while to figure that out but I assure you that is the cause. I had a new set and many old sets. The old gaskets were as hard as a rock while the new one was flexible. That is why in the 1970's we could use those gaskets two or three times before they leaked and now we are lucky if we get a new soft gasket and not a hard one that has been on a shop shelf for 20 years.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21513
Location: Oklahoma City
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| Posted: Tue Dec 23, 2014 9:24 am Post subject: |
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| SGKent wrote: |
next time the covers are off and cleaned with a bead blaster so there is no gasket left on them, put them on the heads and see if they will rock. If they do try to get the rock out. Also my experience is that the cork gaskets are often on the shelves for a long time and they get hard. Combine that with a slight warp in the cover and they weep. It is almost impossible for one to weep when it is flat and on securely.
Further, if one looks at the end of a cover on a T4 engine they will see a cutout and flare. That flare is to help take them off. Many mechanics pry on the corner which warps them. Think of a sheet of plywood lying on the ground. If you pick a corner up the whole sheet twists. That is what causes them to leak. Also - next time you get a cork gasket for one, squeeze them between your first finger and thumb nail. You can tell if the gasket is old or new by how easy it is to squeeze. The easier it is to squeeze, the more warp it will protect against. The hard ones won't seal up with warp. It took me a while to figure that out but I assure you that is the cause. I had a new set and many old sets. The old gaskets were as hard as a rock while the new one was flexible. That is why in the 1970's we could use those gaskets two or three times before they leaked and now we are lucky if we get a new soft gasket and not a hard one that has been on a shop shelf for 20 years. |
Man that is no lie. I have found some off the shelf gaskets that are older and harder than the ones I remove at 30-40k miles.
The nice thing about adhering the gaskets to the valve cover with no sealant on the head s8de is that it requires no prying at all to remove. It does take firm pressure to hold it in proper place to bring the bale over without moving it.
Whether it seals is directly proportional to if the gasket has flexibility as you note. Ray |
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Tcash
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Joined: July 20, 2011
Posts: 12844
Location: San Jose, California, USA
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raygreenwood
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Joined: November 24, 2008
Posts: 21513
Location: Oklahoma City
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| Posted: Tue Dec 23, 2014 10:31 am Post subject: |
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I saw those a while back. I need to research them a little more. If they are injection molded silicone and have a decent durometer. ...like about 40 ....that would be excellent.
However....if they are cast silicone RTV.....they "may" have problems over a long period. Having a wide face of silicone RTV facing oil say 3/16" leaves a lot of surface area open to attack from fuelscin the oil...as compared to a small thickness of only about .001"-.005" max when adhering a cork gasket to the cover with RTV. Oils and fuels have very little wurface area to permeate which is why it works so well.
I will have to look at that. Interesting.
You know.....Fel Pro made a really excellent butyl or, EPDM rubber valve cover gasket for type 4....except..... for the issue that they were designed 1/16" too thin.....and they never fixed this problem to my knowledge. Ray |
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Good Old Dusty
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Joined: September 17, 2016
Posts: 16
Location: British Columbia
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| Posted: Mon Apr 12, 2021 9:23 am Post subject: Re: Oil Pan (strainer) Cover on Type 4 Motor |
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| I have a persistent slow leak at the oil strainer cover. I like the idea of using a sealant between the strainer and the paper gaskets. Has anyone tried using Curil T as the sealant in this area? It is easy to work with and does not require curing time before installation. |
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raygreenwood
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Joined: November 24, 2008
Posts: 21513
Location: Oklahoma City
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| Posted: Mon Apr 12, 2021 1:19 pm Post subject: Re: Oil Pan (strainer) Cover on Type 4 Motor |
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| Good Old Dusty wrote: |
| I have a persistent slow leak at the oil strainer cover. I like the idea of using a sealant between the strainer and the paper gaskets. Has anyone tried using Curil T as the sealant in this area? It is easy to work with and does not require curing time before installation. |
Curil T is not what you want. It is non-hardening. This means that when you use it between a stack of flat surfaces....when you tighten up the stack up...it gets squeezed out.
You want something that hardens or cures. This does not mean that you want something that is HARD and non-flexible once it cures. It needs flexibility. But it also needs to be immobile.
This is why the RTV works so well. It hardens or cures....but essentially turns into a flexible rubber....so it has some stretch.
There are other hardening or curing products that can be used...but they are more like an adhesive and are harder to get off. Example being permatex "Moto seal"...which is very much like Yamabond or Hondabond. Its a rubberized high temp, gasoline and oil resistant...THIN.... gasket dressing. Its made for surfaces like transmission cases, motorcycle engine cases and even our engine cases.
Its about 70%-ish solvent....so when you paint it one....it flows out, evaporates...and tacks up...just like contact cement. Stick the parts together with low pressure so it does not flow out...and when its fully cured its a tough, thin, gasoline proof adhesive sealer. BUT.....when you go to take it off its going to require some nasty gasket remover and probably a wire brush.
Ray |
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Good Old Dusty
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Joined: September 17, 2016
Posts: 16
Location: British Columbia
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| Posted: Tue Apr 13, 2021 9:55 am Post subject: Re: Oil Pan (strainer) Cover on Type 4 Motor |
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Ray, Thanks for the feedback on the Curil T.
I will try a very thin layer of Permatex Copper RTV between the gaskets and the strainer.
The other thing I have noticed lately is that the crush washer supplied with the Brazilian made strainer basket gasket kits are 2 mm larger in diameter than the German OEM (19.9 vs 17.7). The Brazilian washer produces a very sloppy fit on my 78 GE case bolt. It may fit some earlier cases though. Have you tried the RTV technique on the crush washer?
Don AKA 'Dusty' |
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timvw7476
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Joined: June 03, 2013
Posts: 2200
Location: seattle
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| Posted: Tue Apr 13, 2021 12:45 pm Post subject: Re: Oil Pan (strainer) Cover on Type 4 Motor |
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Are you actually crushing the torus-shaped washer under the nut?
That one actually yields as you torque to 9 foot pounds. I've had to go to
9 and a touch more to properly set that seal. I've used Gasgacinch on the green gaskets as well. |
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udidwht
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Joined: March 06, 2005
Posts: 3779
Location: Seattle, WA./ HB, Ca./ Shizuoka, Japan
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| Posted: Sun Apr 18, 2021 4:22 am Post subject: Re: Oil Pan (strainer) Cover on Type 4 Motor |
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My last valve cover gasket changes I tried something new...
1. I rolled very thin RTV on each side of my cork gaskets. Allow to dry before flipping over for micro thin roll on the opposite side.
2. When it came to to replace the old gaskets I swapped in the treated cork ones. Clean the covers real well then placed them in. Done.
I've yet to have to replace them in 12k miles. Not a drop. And they do not stick to head.
_________________
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 |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21513
Location: Oklahoma City
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| Posted: Sun Apr 18, 2021 7:09 am Post subject: Re: Oil Pan (strainer) Cover on Type 4 Motor |
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| udidwht wrote: |
My last valve cover gasket changes I tried something new...
1. I rolled very thin RTV on each side of my cork gaskets. Allow to dry before flipping over for micro thin roll on the opposite side.
2. When it came to to replace the old gaskets I swapped in the treated cork ones. Clean the covers real well then placed them in. Done.
I've yet to have to replace them in 12k miles. Not a drop. And they do not stick to head. |
Yep!
I have been pushing that method for a while....thin roll on of RTV. Typically on the 2nd side......I contact the wet side of the gasket to valve cover and install it on the head with the bale only half closed until it dries fully. Just enough pressure to contact the gaskets flat so they seal evenly to the valve cover.
Once they dry.....fully clamp the cover. They dont leak. They will not "suck in" because they are adhered......and they peel right off when its time to change them. Ray |
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