Is using RTV always a no-no? |
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Is using RTV always a no-no? |
Scott S |
Oct 26 2011, 09:33 AM
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#1
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Small Member Group: Members Posts: 1,697 Joined: 30-April 03 From: Colorado Member No.: 633 |
I have been cleaning/replacing/replating as many little parts as I can while doing my conversion. Last week I replaced the square rear transmission cover at the the tail end of my tail shifter with a newly replated cover and a fresh factory gasket (thanks again Doctor Evil). The thing now leaks like crazy.
When I went to replace this gasket several years ago, I could not find one locally and did not have the time to order one (I was driving the car daily), so I made my own from cork gasket material that I purchased at a local FLAPS. Worked great for 15 years. The factory gaskets are paper. I am wondering if it is to thin and/or has a lack of compression thickness. I am assuming that they are a dry install. Would it be a total hack job to add a bead of RTV to either side of the gasket? I have one new one left. I sure dont want any of that stuff getting into the transmission. Or - I can get out the cork and the sissors again....... Any thoughts are appreciated - thanks! Scott S |
Cap'n Krusty |
Oct 26 2011, 10:04 AM
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#2
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
If you choose to use a sealant, a thin layer (NOT a "bead") of Permatex "Ultra Blue" or "Ultra Black", well massaged into the paper gasket on both sides, would be OK. Just make sure it's applied so there's not a lot of excess that can come adrift in there once the gasket is installed.
The Cap'n |
injunmort |
Oct 26 2011, 11:05 AM
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#3
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Senior Member Group: Members Posts: 1,024 Joined: 12-April 10 From: sugarloaf ny Member No.: 11,604 Region Association: North East States |
an alternative to rtv, i use a product called hylomar (permatex and locktite) i think both market it. developed by rolls royce for jet engines. a thin smear seals everything up nicely and the beauty of it is it does not harden. i have been using it for years on leaky british motorcycle enginges and it really stops the oil hemoraging. also teardowns are easier later on.fwiw.
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DBCooper |
Oct 26 2011, 11:12 AM
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#4
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14's in the 13's with ATTITUDE Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California |
i have been using it for years on leaky british motorcycle enginges and it really stops the oil hemoraging. also teardowns are easier later on.fwiw. I would love to find that this is true, God knows I tried everything else and nothing ever worked, but I'll also be damned if I'll buy another BritBike just to find out. |
injunmort |
Oct 26 2011, 12:58 PM
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#5
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Senior Member Group: Members Posts: 1,024 Joined: 12-April 10 From: sugarloaf ny Member No.: 11,604 Region Association: North East States |
by lothars hammer i swear it true. my commando is sitting in the same spot since last winter and there is not a drop of oil around it. yamabond on the cases, pematex spray copper on the head gasket and hylomar everywhere else. there is no cure short of glyptone for the porous castings though and i have seen it fail in cases so i dont uses it. fwiw.
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injunmort |
Oct 26 2011, 12:59 PM
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#6
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Senior Member Group: Members Posts: 1,024 Joined: 12-April 10 From: sugarloaf ny Member No.: 11,604 Region Association: North East States |
by lothars hammer i swear it true. my commando is sitting in the same spot since last winter and there is not a drop of oil around it. yamabond on the cases, pematex spray copper on the head gasket and hylomar everywhere else. there is no cure short of glyptone for the porous castings though and i have seen it fail in cases so i dont uses it. fwiw.
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Scott S |
Oct 28 2011, 10:17 AM
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#7
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Small Member Group: Members Posts: 1,697 Joined: 30-April 03 From: Colorado Member No.: 633 |
Tried the RTV thing last night – still had big leaks. Per the Capn’s advice, I refused to simply load the thing full of RTV and “squish” it shut. (IMG:style_emoticons/default/barf.gif)
The thing did not leak before – what the hell changed? The cover plate changed. I had picked up another one to send out for replating so I would not have to drain the transmission and leave it open while I waited for it’s return (and while waiting to find the time to re-install it). The “new” cover plate was junk. It was twisted and it appeared to be made of thinner metal. The flanges were also just a touch shorter. Sure looks pretty though. (IMG:style_emoticons/default/dry.gif) I hit the original plate on the wire wheel, painted it up and threw it on. No more leaks. Note to self – inspect your parts. Especially before you make them look pretty. (IMG:style_emoticons/default/headbang.gif) |
Cap'n Krusty |
Oct 28 2011, 10:41 AM
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#8
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
an alternative to rtv, i use a product called hylomar (permatex and locktite) i think both market it. developed by rolls royce for jet engines. a thin smear seals everything up nicely and the beauty of it is it does not harden. i have been using it for years on leaky british motorcycle enginges and it really stops the oil hemoraging. also teardowns are easier later on.fwiw. Loctite IS Permatex, and has been for years. The Cap'n |
pcar916 |
Oct 28 2011, 04:11 PM
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#9
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Is that a Lola? Group: Members Posts: 1,523 Joined: 2-June 05 From: Little Rock, AR Member No.: 4,188 Region Association: None |
by lothars hammer i swear it true. my commando is sitting in the same spot since last winter and there is not a drop of oil around it... Yeah, my Norton didn't leak either after I put it back together. Used an old aircraft powerplant method of putting a silk thread in the middle of the sealer. But this is a sheet-metal part, not milled pieces. You're sure it has oil in it right? |
Cap'n Krusty |
Oct 28 2011, 07:21 PM
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#10
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
by lothars hammer i swear it true. my commando is sitting in the same spot since last winter and there is not a drop of oil around it... Yeah, my Norton didn't leak either after I put it back together. Used an old aircraft powerplant method of putting a silk thread in the middle of the sealer. But this is a sheet-metal part, not milled pieces. You're sure it has oil in it right? I've used thin copper wire. Never thought of silk thread ................... The Cap'n |
Katmanken |
Oct 29 2011, 05:15 PM
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#11
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You haven't seen me if anybody asks... Group: Members Posts: 4,738 Joined: 14-June 03 From: USA Member No.: 819 Region Association: Upper MidWest |
Dang,
Never thought I'd hear the Cap'n admit there was an engine build trick or two that predated him... (IMG:style_emoticons/default/biggrin.gif) |
injunmort |
Oct 31 2011, 06:31 AM
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#12
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Senior Member Group: Members Posts: 1,024 Joined: 12-April 10 From: sugarloaf ny Member No.: 11,604 Region Association: North East States |
i am pretty sure all the oil is in the sump as it has been sitting unloved for a year.
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DBCooper |
Oct 31 2011, 07:09 AM
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#13
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14's in the 13's with ATTITUDE Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California |
Dang, Never thought I'd hear the Cap'n admit there was an engine build trick or two that predated him... (IMG:style_emoticons/default/biggrin.gif) I'm surprised too. That was one more BritBike trick that never worked for me, but we used it on aircooled VW's in the 60's, supposedly stolen from the aircraft guys. |
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