question: how to seal metal-metal without gaskets???

[atch]

bryan's post about installing a thermostat housing with or without a gasket brought to mind a question i've been pondering for over 30 years.

i've got a bsa that i've had since 1973. i've got a shovelhead harley that i've had for years. both of them leak oil from the cases. i remember an article in hot rod magazine (or some magazine at least) back in the 60's where someone built a nascar engine without any paper gaskets to prove that it could be done. i think it was permatex, but it could have been someone else. it also seems like it was one of the chevrolet cars, maybe smokey's.

so the question is: is there a sealer out there that will hold oil if i disassemble the cases and reassemble them with the sealer on the mating surfaces? if so what is it and where can i get it?

my current solution is that i ride the wheels of of my twin-cammer and i just don't ride either of these other bikes.

there must some bikers out there that have been around this block before and figured out a solution. i'd sure like to draw on your knowlege base if you don't mind.

TIA.

[REJ]

I'm no expert on bikes, but the best sealer I have found is the silicone for a Toyota oil pan. It is only available from Toyota, about 13.00 a tube.
I will give you fair warning, if you use this, be prepared to cut the pieces apart with piano wire when you go to remove them. This stuff is the best sealer I have found.
My 02 cents worth.

[manyolcars]

Old Harley riders have always told me to use silver paint. Some suggest letting the paint sit until you can pour off the oil and just use the silver. This was a common practice to increase compression, with no head gasket. I do it with a head gasket to improve the seal between the aluminum head and iron cylinder.

[zman]

Yamaha Durabond is the bomb. I believe #6 is the one you want it's the gray stuff. It'll seal it up very nicely. Used it all the time building race motors. Especially 2 strokes where the crankcase can absolutely not leak.

[Mojo_AL]

I rebuilt my Triumph tiger, and used Three Bond and Caterpillar stuff. Three Bond worked OK between my engine cases, they don't leak at all, but some other places do leak. Caterpillar gasket maker is great, no leaks where I put it. A guy also told me he rebuilt his BSA using it, and the bike doesn't leak.

A friend of mine saw a guy flip an oil drum so a plug would be facing up, seal the plug with "The Right Stuff" gasket maker, and put the drum back on it's side. No cleaning, anything. My friend swore that it never leaked again. It might be worth a try.

Good luck with your bike!

[Kevin Lee]

Air cooled VW cases are split right down the middle - no gasket. I'd ask around and see what the VW guys use...but that Toyota stuff sounds good.

That Durabond sounds good too.

[manyolcars]

I've never had a leak at the case seam. It sounds like the case halves came from different engines. Maybe you should use valve grinding compound to lap the cases in so they fit each other.

[Ayers Garage]

[ QUOTE ]
Air cooled VW cases are split right down the middle - no gasket. I'd ask around and see what the VW guys use...

[/ QUOTE ]

I'm very carefully alluding to VWs here...Aviation Permatex is what they use between the case halves. No gasket or anything, just a light coat brushed on. About 3 bucks a bottle at a VW place.

Coincidentally, I used it on airplane engines too, back when I worked as an A&P mechanic.

[CURIOUS RASH]

<font color="green">Black Weatherstrip adhesive.

When I built this last motor I put Vortec heads on it.

They are the center bolt kind but I wanted to run "Ole School" Offies so I ordered some adapters from Pace, scanned them on our flat bed scanner at work, and cut them out with our WaterJet. Sent the things back to Pace. http://www.jalopyjournal.com/ubbthreads/images/graemlins/blush.gif

Anywho, The adapters had an o-ring groove which was going to be quite difficult to replicate and not very effective anyway.

So I was wondering this same thing and started asking around.

FTF told me that the Black adhesive from 3M is ALL he uses for every gasket, everywhere.

I was skeered so I looked up the specs on the net and was surprised to see that it is better suited as a gasket material than most gasket materials.

So I tried it, I put a THIN layer on the adapter and a THIN layer on the mating surface, let them sit til they tacked up and then put them together.

Works like a charm and I'm pretty sure I will need to soak the parts to get it apart.

I have not tried it on parts that are constantly holding oil though.

RASHY </font>

[Spitfire1776]

The real question is what would Fat Hack use? http://www.jalopyjournal.com/ubbthreads/images/graemlins/smile.gif

I would think the aviation permatex would be the best bet for reliability. Big staple of airplane restoration, and you figure it can't be a subject of hoi-paloi gimmick gadjetry. It would have to stand up to regulation standards and dire abuse.

[millerkustoms]

A lot of VW people use gasgacinch(spelling is a complete guess) to seal cases. But the toyota silicone works wonders. When I was a Lexus tech, we had a Dealer Special Service Tool for removing engine and trans pans. It was a knife with a surface to hammer it around the perimeter of the pan. The stuff rarely leaks if used correctly.

Black, for engine oil and sealing water.
part # 00295-00103 12.95 list

Red, for sealing gear oil, and atf
part # 00295-01281 20.38 list

[Morrisman]

Whatever you use, it won't be worth a dime until you get the surfaces totally clean and oil free. Chemical clean, like spray on evaporative contact cleaner, something that leaves zero residue. You can't stick sealant to grease, so you're wasting your time until you clean it all up http://www.jalopyjournal.com/ubbthreads/images/graemlins/frown.gif

Good stuff will fill a small gap as well http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[manyolcars]

When your cases fit each other properly, no sealer will be needed

[cornfieldrodder]

Loctite 515 works very well. It is an anarobic liquid sealer. The number may be different in smaller packages. The one here is a 7.5 oz bottle, or something like that. It is designed to seal solid, flat surfaces that may be submerged in oil. Works well for vertically split cases. The sealer not between the surfaces does not dry, of course, so use it sparingly. It sticks parts together really well and requires brake cleaner or some such solvent to remove after its set. It does not seal gasoline for crap!

[Baron Von Mike]

[ QUOTE ]
Yamaha Durabond is the bomb. I believe #6 is the one you want it's the gray stuff. It'll seal it up very nicely. Used it all the time building race motors. Especially 2 strokes where the crankcase can absolutely not leak.

[/ QUOTE ]

I'd have to second the Yamabond suggestion, for all the same reasons. Recommended to me by a small engine mechanic and have used on many 2-strokes and cars. I use #4.

[JSM56]

Hondabond is also great, used it all the time when i worked at the honda motorcycle dealership. never had a problem, even used it on slip together exhaust to fix leaks.

['Flyin' Dutchman']

I often use Hylomar Aerograde. It's the blue silicone stuff.
I used it on the cases of my Triumph too, it never leaks.

http://www.hylomar.co.uk/aerograde.htm

[SnoDawg]

Hylomar is great shit another suggestion use some silk thread run along the splitline along with the hylomar or permatex it will act kinda like a gasket. I did this with a VW eng I put together in 88 no leaks so far.

[noboD]

Back when there were lots of air cooled VWs, I used Permatex Aviation. A local shop used the yellow windshield goo and you had to beat the cases to get them apart. As everyone has said, make it clean first no matter what you use.

[bulletproof1]

i use RIGHT STUUF from napa,its made by peratex and it works on everything iv ever tried it on,i rebuild allot of t-cases and rear axles and every one of them get right stuff .most of the alium cases dont have gaskets between the case halfs ,and as long its clean and dry when you apply it your good to go

[Mojo_AL]

Talking about surface prep, here's a tip. If you have bent, gouged or cracked contact surfaces and you do not or cannot file them smooth, try covering the surface with 5 minute epoxy, let dry and then file smooth. Kind of like Bondo for engines. It works great for thin spots you don't want to make thinner or cracked surface.

I don't know about using it between cases, but for clutch, timing or tranny cover, it works well. It helped me a lot on my Triumph.

[Flat Ernie]

OK - I'm drunk &amp; typing on a German keyboard. BUT!! Here is my opinion:

Only pussys &amp; sorry engine builders use gasket "sealer" - if your cases, gasket surfaces, whatever are clean, flat, &amp; true, you don't need jack shit! Put some grease on the gasket (not paper, but proper gasket) &amp; run it!

If you're sloppy, lazy, or don't give a damn - slop as much RTV/silcone on that joint until it makes you feel good/better about yourself...

RTV is for pussies who don't know how to put together a leak-free engine. Do you really think Henry Ford had RTV?

OK - my time is about to expire, so I will address the flames later...

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

[ESnacky6]

Well at least everybody agrees on the same product...!! http://www.jalopyjournal.com/ubbthreads/images/graemlins/wink.gif
Hahahahaha...!!! Damn.....


I would also recommend 'The Right Stuff'.... works great..!!


Later, Snacks.....

[Flat Ernie]

So now I'm slightly hungover &amp; typing on a normal keyboard &amp; can read that you want to seal something without gaskets...

Aviation permatex if you want to get the parts apart later.

Gorilla Snot (aka - 3M weatherstrip adhesive) if you never care to get them apart again

If your cases aren't perefctly flat, instead of using epoxy (which may/may not work), use MarineTex which is a type of epoxy specifically made for this type of repair.

Your case halves need to be true. Lap them in on a flat surface &amp; lap them to each other. Just enough to ensure they're true.

Sorry for the previous drunken rant...I hate taking apart stuff idiots have gooped together w/RTV and other stuff.

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

[Ayers Garage]

I know nothing about the motorcycle engines, so this may be irrelevant.

The case halves of VWs and aircraft engines really are a special deal and require the proper sealant. The relationship of the two case halves sets the bearing crush. Lots of VW engines have been ruined by using the wrong sealer between the case halves. If the sealant does not squish down properly, the halves won't fit together properly and the proper bearing crush will never be achieved. For this reason, there is no option of lapping the parts to fit together better. You have to use sealant to take up the irregularieties between the two pieces.

Aircraft engines are usually put together by more knowlegable folks than the typical VW engine. Also, the parts are better quality. Lots of guys use a single strand of silk string between aircraft engine case halves to seal them between each other.

[Morrisman]

[ QUOTE ]
When your cases fit each other properly, no sealer will be needed

[/ QUOTE ]

Dream on dude http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

Mean while, back in the real world....
I've used this for years at work, on big industrial engines, and it sticks like shit to a blanket. A very thin smear, on a CLEAN surface, and you're in business http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif