RTV tips?

[Jimnc]

which is best for valve covers .i bought an aftermarket alum. cover it came with the rubber and metal gasket. i cant get it to stop weeping. thanks jim

 

[5-90]

I like LocTite 518 for valve covers. I've covered my procedure on here a few times - see if you can turn anything up.

5-90

 

[Blaine B.]

I used the red Permatex to seal my 8.25 and D30, works great!

LocTite #271 Exhaust Manifold Hardware - since this can take the heat, would it be something to temporarily patch a exhaust header hairline crack? Maybe my only resort is actually welding or replacing.....just curious :cheers:

 

[5-90]

I used the red Permatex to seal my 8.25 and D30, works great!

LocTite #271 Exhaust Manifold Hardware - since this can take the heat, would it be something to temporarily patch a exhaust header hairline crack? Maybe my only resort is actually welding or replacing.....just curious :cheers:

No. LT271 only retains the screws - it won't patch anything. You'll want JBWeld or some other "metal-bearing" two-part compound to effect a temporary repair.

Check your engine mounts, you'll probably want to replace them when you put a new manifold on. It seems that most manifold cracks are accompanied/preceded by engine mount failure (either total or partial,) and the relative motion of the engine to the chassis strains the exhaust manifold collector.

Replace all three - both engine mounts, and the transmission mount.

5-90

 

[mikeny59]

Acetone works very well to degrease - don't be afraid of using plenty of paper towels, recyle 'em anyway (brake bleeding, grease fittings, etc...), got a garbage pail full of 'em.

If rtv needs to set up in a cold environment (winter/outside/detached garage), bungee cord or two an old heating pad around pumpkin, I think most rtv directions say fully cured in 24 hours above a given temp.

BTW, Friend bought '06 Xterra, Allen plugs on bottom of both dif housings (not covers), think about it... but that's another thread.

5-90, thanks for sealant primer, definitely worth the printer ink...

 

[5-90]

BTW, Friend bought '06 Xterra, Allen plugs on bottom of both dif housings (not covers), think about it... but that's another thread.

I have been thinking about this - probably brazing or hard-soldering a bung somewhere into the case that will accept a drain plug. Just haven't found a suitable plug/bung combination, yet...

5-90

 

[Blaine B.]

Engine mounts were replaced shortly before I purchased the XJ. On the old radiator I also did see some marks on it from the fan hitting it, so I guess those mounts really did needing a changing!

How often should things like those be changed? I'd say they were changed maybe 3 years ago or so, just a guess. Maybe less.

 

[old_man]

The key is to get the surfaces oil free and to let the RTV have a set time before assembly. I use paper towel and ether starting fluid to clean both surfaces. I put a bead of the RTV on and let it sit 15 minutes before assembly. Also do not over torque or you will squeeze all the RTV out and have a lousy seal.

When using a paper gasket, I do a light coat with my fingers on both sides of the gasket before assembly.

 

[5-90]

Engine mounts were replaced shortly before I purchased the XJ. On the old radiator I also did see some marks on it from the fan hitting it, so I guess those mounts really did needing a changing!

How often should things like those be changed? I'd say they were changed maybe 3 years ago or so, just a guess. Maybe less.

It varies. If you do annual or semi-annual inspections (I do quarterly "surface" inspections and annual "detail" inspections,) you can use a "mirror on a stick" to check the mounts from the front and rear - which usually shows up deterioration in the rubber cushion rather better than just looking down on the thing. You should have no trouble finding one locally to you (I have one made by General Tools - it's on a telescoping stick, and cost me less than $10.)

I've seen engine mounts last anywhere from 5 to 30 years - it mainly depends upon operating conditions (engine vibrations, torque applied, engine leaks, and what-have-you.)

Also, take the time to check the "rear engine mount" (under the transmission) as well - since a failure here will accelerate wear on the forward mounts. They should typically be replaced all at once.

5-90

 

[mikeny59]

I have been thinking about this - probably brazing or hard-soldering a bung somewhere into the case that will accept a drain plug. Just haven't found a suitable plug/bung combination, yet...

5-90

I've been looking at those replacement magnetic drain plugs, say a 1/2"-20, cutting off head hex head, hack sawing slot for flat head screwdriver - no lost ground clearance.

Drill/tap appropriate hole, but may have problem w/seepage seeing there's no washer. Could leave head on, but would lose a bit of dif/ground clearance.

I've heard that difs were designed w/o drain plugs so one has to inspect innards, but noise is late/but enough warning to me to open/rebuild a rear.

Changing dif fluid/gasket is the worst... rather change a diaperuke:

 

[twisted_ed]

RTV is not obselete. Any good mechanic will use RTV, its tried, tested and true. I would rather use RTV than to try to make a gasket.

Plus you have to remember alot of setups from the factory use RTV, if you go replacing them with RTV you run the risk of having clearance issues as rubber can add so many extra "thou" where it shouldnt be

 

[goodburbon]

I'm in the "hate" RTV crowd. I have 2 leaky diffs, a leaky t-case and formerly a leaky transmission pan. Permatex Blue will never again be in my toolbox.

 

[SuperRA]

IMHO If you have a near perfect surface and the factory originally had a paper gasket there then paper is the way to go. But for most of my resealing jobs, I like to use "The Right Stuff", it seems to work the best out of all the RTVs. I think the facory specifies sealers because they don't finish the sealing surface as smoothly as a paper gasket would like, thus costing them less.

 

[Slonopotam]

...I have 2 leaky diffs, a leaky t-case and formerly a leaky transmission pan. Permatex Blue will never again be in my toolbox.

I've tried to seal d30 and 8 1/4 diffs without a gasket. d30 works fine every time, 8 1/4 leaks every time. I guess, d30 has a better diff cover.
However, when guys at Rearend specs installed truetrac in my 8 1/4 they did not put a gasket and it still held oil good. It's either my hands or they used some other RTV, not permatex.

Andrey

 

[Hellbent]

a second vote for permatex's "right stuff". for rtv, the stuff is amazing if you put it on a CLEAN surface. i've used it to seal coolant, atf, motor oil, gear oil, pretty much every automotive fluid that could leak from a jeep. not one single leak from the stuff in the couple years i've used it.

 

[Tradesman300]

Acetone works very well to degrease - don't be afraid of using plenty of paper towels, recyle 'em anyway (brake bleeding, grease fittings, etc...), got a garbage pail full of 'em.

X2 on the acetone. I in fact just finished my dif cover (black bolts and olive green cover, couldn't resist) and no leaks. I have had good luck with RVT over the years, but I am also a very avid cleaner and polisher of any part that I remove, so I put things back on in 'like new' condition. I never liked paper gaskets unless they were smeared with RVT!

 

[mikeny59]

Just remembered, don't forget cleaning housing most meticulously surrounding mating surfaces, especially pumkin.

Many a time I couldn't immediately line up starter bolt holes w/o squishing the rtv all over the place, convinced oil/dirt/grease contamination will find it's way in and ruin a perfectly executed mating surface cleaning.

That with crossthreading one lower bolt led to some seepage, one time out of maybe twenty r&r's, f&r.

Today I did pick up a pair of 1/2"-20 magnetic drain plugs, going to take the plunge and drill those punkins, tired of this archaic method of fluid change, after all, Halloween's comin' up. Get it, punkins?!?:confused1

 

[fizassist]

For cleaning the mating surfaces, I just use brake cleaner. It's the fastest and most effective way to degrease anything that I've found. It's worth the couple bucks for speed & ease of use. I've never had trouble with leaks using RTV on diffs or tranny pans.