rtv on valve covers ?

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candymancan
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rtv on valve covers ?

Post by candymancan »

My valve covers were leaking a lot of oil down the side of the engine and burning off on the exhaust manifolds. they were white ashy where the oil burns on.. To fix the leaks and stop a potential fire hazard i just took the covers off and pealed off the rock hard gasket cleaned it up and tapped the overtorqued pan as straight as i could on the bolt holes. cleaned up the crusty oil in the cover and put The Right Stuff on it and put it back on. Doesnt seem to be leaking anymore when i watched it run with a flash light but well see.

A friend of mine just chewed me out for using rtv on it claiming itll break lose and get in the oil and blah blah.

Tbh ive used the right stuff on my transmission. diff covers.. water pumps and timing covers thermostat housings and no issues..

In fact when i took the oil pan off my wagoneer. the old cork gasket was hard as a rock and broke off into the oil pan (before i took it off) and coverd more then half of the pick uo tube blocking the screen. So how can rtv be any worse then cork when it disintegrates ?
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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fulsizjeep
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Re: rtv on valve covers ?

Post by fulsizjeep »

I'm not an engineer and this is just my opinion... More is not better.
I have torn down a few FSJs for parts and have found occasions where there is RTV inside tranny, engine, axles and transfer case. Upon closer inspection it was always an application of too much to way too much sealant and it was squished out in all directions. A couple of the QuadraTracs I tore down had RTV all the way inside the brake cones making it almost impossible to get proper oiling inside. RTV is typically fine when you don't squeeze the whole tube on it. :)
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tedlovesjeeps71
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Re: rtv on valve covers ?

Post by tedlovesjeeps71 »

Concur with fsj^^
A little goes a long way. I'll often use adhesive instead of rtv and a quality gasket.


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Topic author
candymancan
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Re: rtv on valve covers ?

Post by candymancan »

well i didnt put a lot on just enough i put a tiny bead on and smear it flat with my finger. I might put more to some spots that seem too thin but that it.
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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44bz
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Re: rtv on valve covers ?

Post by 44bz »

I used the right stuff on my water pump without issue. The only problem I've had is getting the parts apart again. The right stuff seems to bond really well, seals well too, but it's a pain when you need to service something. On most gaskets Ive had really good luck just spraying both sides with the copper sealant and slapping it together.


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Stuka
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Re: rtv on valve covers ?

Post by Stuka »

I always use the cork gasket with Permatex High Tack.

It never fully hardens like RTV, so by staying pliable, it holds up better under vibrations and can fill into any gaps that fill up. You can get it in a can for 5-8 bucks.
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tgreese
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Re: rtv on valve covers ?

Post by tgreese »

Straightening the flange usually helps a lot. Over-tightening distorts the cover and makes them leak. V8 valve covers shouldn't leak. The steel 258 valve cover is terrible about leaking, but the V8 covers should not leak if they are straight.

In the past, I have glued the gaskets into the cover, and used a very thin layer of RTV on the side that contacts the head.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
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tedlovesjeeps71
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Re: rtv on valve covers ?

Post by tedlovesjeeps71 »

tgreese wrote:Straightening the flange usually helps a lot. Over-tightening distorts the cover and makes them leak. V8 valve covers shouldn't leak. The steel 258 valve cover is terrible about leaking, but the V8 covers should not leak if they are straight.

In the past, I have glued the gaskets into the cover, and used a very thin layer of RTV on the side that contacts the head.
And Nothing leaks like a Plastic 258 cover!!!


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Tatsadasayago
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Re: rtv on valve covers ?

Post by Tatsadasayago »

Stuka wrote:I always use the cork gasket with Permatex High Tack.

It never fully hardens like RTV, so by staying pliable, it holds up better under vibrations and can fill into any gaps that fill up. You can get it in a can for 5-8 bucks.
I swear by Hi-Tack Aviation!
I've learned that while RTV has it's uses in several areas, I believe it is one of the most abused materials by so many who don't understand it's purpose.
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tgreese
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Re: rtv on valve covers ?

Post by tgreese »

Also - make sure the oil can drain back to the crankcase. There are passages in the head that need to be clear. If oil pools on top of the head, the covers are a lot more likely to leak.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
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candymancan
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Re: rtv on valve covers ?

Post by candymancan »

The holes are pretty large. looked clean to me. There was a little bit of sludge in the heads though.. goopy stuff i could smear off the iron.. Kinda iritating its from people who dont do oil changes.... Oil pan was fairly clean had a little sludge on bottom.

I think i might run some rilsone engine oil supliment in there to clean up some of the sludge or try anyway.

drivers side started leaking again had to take it off and spent like an hour making sure the cover was as flat as possible. Seems to not leak now.

I dont really like these AMC heads. they are unfinished.. Bumpy iron casting.. No surfacing for the valve covers...
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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tedlovesjeeps71
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Re: rtv on valve covers ?

Post by tedlovesjeeps71 »

candymancan wrote:
I dont really like these AMC heads. they are unfinished.. Bumpy iron casting.. No surfacing for the valve covers...
That's because they were cheap asses.
If you complain about their poor machining they would probably just shrug.

Ain't My Concern... AMC

Topic author
candymancan
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Re: rtv on valve covers ?

Post by candymancan »

lol yea.. The 360 magnum iron heads are machined smooth.. These AMC heads.. the surfaces looked like an ogres face all pitted litterally they just put a gasket over the casting lol.. No wonder they leak.

at least chrysler i hear added more bolt holes but they voulda at least machined them
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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az chip
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Re: rtv on valve covers ?

Post by az chip »

I know everyone has their favorite. My favorite and champion sealant is Hylomar. Good enough for aircraft engines, good enough for me. Google it. Get it. Know it. Love it. Although I do use Hi Tack on the water pump gasket.
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Re: rtv on valve covers ?

Post by HeavyMetalThunder_81 »

candymancan wrote:lol yea.. The 360 magnum iron heads are machined smooth.. These AMC heads.. the surfaces looked like an ogres face all pitted litterally they just put a gasket over the casting lol.. No wonder they leak.

at least chrysler i hear added more bolt holes but they coulda at least machined them
Chrysler made no changes to the AMC V8 other than casting 5.9 into the blocks instead of 360. I would personally prefer a slightly rough surface so my gasket has something to grip onto instead of sliding out like the intake end seals do.
I hate RTV. It has its place in certain areas and applications but people abuse it as a gasket substitute. I learned the hard way as a young mechanic and have had more things leak from using RTV than I have ever from correctly installing the proper gasket where it is needed. If it came with a gasket from the factory it should get a gasket when removed/replaced. On occasion I do use some form of gasket dressing (Hi-Tack/gorilla snot/gasgacinch/what-have-you) or spray copper on my gaskets but that is all. Just my .02
-Jonny B.
1979 Cherokee Golden Eagle - UNDER CONSTRUCTION
7" lift, 35x12.5x15
AMC 401 - Pro-FLo 4 FI
NV4500/NWFBB/NP205 - Triple Stick'd
F D44 - 4.10, Eaton E-Locker
R M23 - 4.10, Detroit Locker

1979 Cherokee Chief - Parts
1979 Cherokee Chief - Parts
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Topic author
candymancan
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Re: rtv on valve covers ?

Post by candymancan »

I was told they added more bolt holes. How many bolts did older 360's have.. Mine has like 6 or 8 i think if i remember
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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HeavyMetalThunder_81
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Re: rtv on valve covers ?

Post by HeavyMetalThunder_81 »

They all have 7.
5 across the bottom and 2 on top.
-Jonny B.
1979 Cherokee Golden Eagle - UNDER CONSTRUCTION
7" lift, 35x12.5x15
AMC 401 - Pro-FLo 4 FI
NV4500/NWFBB/NP205 - Triple Stick'd
F D44 - 4.10, Eaton E-Locker
R M23 - 4.10, Detroit Locker

1979 Cherokee Chief - Parts
1979 Cherokee Chief - Parts
1979 Wagoneer - Sold
1981 Cherokee Chief - Cubed

Topic author
candymancan
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Re: rtv on valve covers ?

Post by candymancan »

Okay dunno where i read that then
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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