[eedneco]

Hi all,
I wanted to check for feedback on something I've considered a couple times when I had my motor apart, but haven't done. I know that the general question of using RTV instead of gaskets is somewhat contentious, and the results depend a lot on how cleanly the application is done. IM(v)HO, something like the sump gaskets can be done quite well with RTV, especially if you're using a girdle, which gives you a double joint.
But how about the timing cover ? The main blocker from what I can see is that the intermediate timing gear runs out of end play before the timing cover is tight to the block, so one would have to take some material off the thrust bearing (or whatever I should call it) to compensate for the gaskets' absence.
What do you all think ?
Regards
Neil

 

[dmericas]

Why not use a high quality gasket sealer, like Hylomar?

 

[slyalfa]

I used to use RTV on everything with no problems. but the smell will kill a O2 from a long way away. you can get O2 safe RTV That I use from time to time. but I have moved on to yamabond/ultragrey /Threebond for most things.

but RTV is good for a cover you might want to popoff and reuse. I have coated a new(and old) gaskit with O2 safe RTV and when I pop off the cover I have a rubberized gasket that can be reused. the 2nd time I just put it on dry and it seems to work as the RTV soaked in will seal it.

 

[Andrew]

I generally don't use any sealer on the cam cover, and use original Alfa gasket from Jon Norman, which do fine in more than one use if you don't put goop on them that tears them on removal. I don't have leakage problems. The rubber "reusable" type I found didn't stay in place at all and oozed out of position too readily.
Andrew

 

[eedneco]

Hi guys,
Thanks for the feedback so far. I should note that I'm really after thoughts around its use on the timing cover, as opposed to other joints. I agree, potentially hylomar / yamabond type sealers could be used instead of RTV, for example I used hylomar on the spica throttle bodies last time instead of paper gaskets.

But for the timing cover, there's a special "issue" if you want to do away with the paper gaskets, and that's the end play on the timing chain's intermediate gear, which ends up too tight.

Basically I'm wondering if some builders see enough benefit in eliminating the paper gaskets to be worth adjusting the intermediate gear end play (which requires some machining, or at least some patient and careful work with emery paper or similar).
Cheers
Neil

 

[alfaparticle]

Be careful with Hylomar. a small amount of it in the oil pan will form a gluey mess that will stick to the oil pump pickup. I have experienced this and so have others. There was a long thread about it a few years ago. I had been using it on cam covers. I now use Permatex Grey. I will still use Hylomar on the induction system but not anywhere were it can come into contact with engine oil.

 

[gigem75]

a very thin coating of the ultragrey on the front cover gaskets works well for me. I usually put a dab on thumb and forefinger and work it onto the gaskets gently and thinly, then install the gasket and cover. Don't forget the square O ring

 

[eedneco]

Hi guys,
Ed, interesting warning on Hylomar, thanks.

So - at least for now, I'll assume that few (if any?) people have attempted to eliminate the front (timing) cover paper gaskets in favour of only a RTV seal.

Fair enough, then.
Cheers
Neil

 

[kcabpilot]

The only significant pressure on the timing cover gasket is at the coolant passage to the water pump, the rest is just crankcase vent pressure which is normally negative. What I mean is that there really isn't and never has been any sort of particular problem with the timing cover gasket so why would you go to the trouble of worrying about gear end-play just so you could use RTV?

Personally I'm not a big fan of RTV. The stuff is absolutely amazing but there are a couple of issues as I see it. Number one - to virgin metal the stuff sticks like crazy but it's darn near impossible to get completely cleaned off. Any subsequent application of RTV will not work well because absolutely NOTHING will stick to already cured RTV - not even new RTV itself. Nor will any other normal gasket sealer. So I prefer not to use it on engines. It's great for screen doors and a million other things but not anything that you might want to take apart one day and rebuild.

 

[eedneco]

Well, everyone has their preferences, for sure.
Some builders like RTV, used well, to create a stronger assembly, with less "squish" from the gaskets. In my own experience, I've had trouble with the gaskets ripping at the water log, and also with them compressing over time and allowing the front cover to loosen. About disassembly, I don't worry about that too much - I prefer to put my car together in a way that makes it hard for it to come apart, either by my own actions, or by itself. I feel better that way.
Cheers
Neil
PS if memory serves, scotchbrite or a fine emery paper worked well the last time for getting RTV remnants off of flanges. Scrapers and such definitely don't work well for me.