Timing Chain Cover Questions

[JM70911T]

I am in the process of installing timing chain cover gaskets on my 70 911T w/ original 2.2L motor.

The previous owner upgraded to Carrera tensioners but neglected to use gaskets leading to leaks.

Based on Waynes rebuild book I am not using sealer just a gasket with both surfaces cleaned up and dry.

Is this approach correct ?

I have run into different opinons on this topic

Also what should I torque the timing chain cover banjo bolts (hydraulic feed line to tensioner) too ?


I have searched for this info on the bbs without much luck.

Thanks in advance.

Jon

[TWork]

I've just finished up a top end rebuild on my 3.0 SC and I had the same question. I looked in Wayne's book and a few other sources, and the best I came up with was that the gasket goes on dry. Its still early, but I've had no leaks from the covers.

T.

[walt]

I also installed my cover dry. Torque spec for the banjo bolt is 7.4 ft. lbs. Did you use aluminum sealing washers for this joint?

[Carrera3.5L]

I installed mine dry as well and most professional engine builders that I know do so as well.

Just make sure that the chain housing covers have a nice, flat surface and aren't warped, similar to how you would prep valve covers.

Ralph

[jimbauman]

I'll throw in my two cents worth for no gasket goo as well.

I installed my chain cover gaskets dry. Installed all the nuts finger tight, then tightened to spec in a pattern just like you would with head bolts. No drips, no runs, no errors!

JB

[JM70911T]

Thanks for all the tips. The torque value for the banjo bolt is hard to find.

Jon

[KTL]

I'll be the devil's advocate here.

When I did my chain box cover gaskets, I sprayed them with Permatex copper gasket sealant

Permatex Gasket Sealants

Figured it'd help prevent deterioration of the gaskets over the long term. I only used the copper stuff because that's what the store had in stock. Otherwise I would have used the standard stuff.

The torque value for the banjo bolt is more by feel than torque spec. number. Simply tighten the bolt until you feel it contact the sealing washer(s). Then another 1/4 turn of the wrench is plenty. Any more tight and you're just unnecessarily crushing the sealing washer.

[donbecker1234]

Sorry to revive an old thread here but I’m doing my timing covers and would like to hear any other opinions on gaskets...dry or with something?

I was thinking of using Loctite 574, but haven’t researched it thoroughly yet.

I’ve already sanded my covers.

I cannot think of a downside to using some sort of sealant on the gasket.

[eastbay]

I use Permatex Aviation brush on sealer, dry gaskets leaked for me. Mag covers definitely need a sealer.

[AndrewCologne]

I use always Curil-T (Green) from Elring, applying just slight/thin makes it totally leakproof.

[donbecker1234]

Adding some sealant seems like cheap insurance / help with leaks to me, can't imagine any downsides to it.

[HaroldMHedge]

Threebond 1104 (now 1184) is recommended in the The Complete Engine Sealant Thread... for sealing the Cam Chain Housings to Case in Post 646.

[donbecker1234]

Originally Posted by HaroldMHedge

Threebond 1104 (now 1184) is recommended in the The Complete Engine Sealant Thread... for sealing the Cam Chain Housings to Case in Post 646.

Thanks for the link Harold.

I read that part of the thread but wasn't able to discern how to compare my plan of using Loctite 574 as opposed to Threebond 1184.

Do you have any information for that comparison?

I've read the engine sealing thread before, but one of the things I struggled with was the sheer number of different sealants that are being used. I'm not a mechanical engineer nor a professional mechanic, but I can't imagine that there are that many unique sealing situations on these engines. I'm open to being wrong on that however.

[nene]

I opened up my chain covers and used only the gaskets and no sealer and no leaks. The old gaskets had no sealer applied as well.

serge

[Walt Fricke]

I like Curil as suspenders for the belt. 574, for me, sticks things too tightly. But I build my motors with an eye to taking them apart every 100-200 hours on the track. And reuse the gaskets if not torn.

In terms of sealing, extra sealants of almost any stripe seem to be OK. I wouldn't use silicone, though. Yama/Honda bond (gray stuff) would probably do all by itself, with no gasket.

[dannobee]

Originally Posted by Walt Fricke

Yama/Honda bond (gray stuff) would probably do all by itself, with no gasket.

That's exactly how "modern" engines are assembled. Metal to metal with no gaskets. Just make sure to clean up the parts with brake clean or alcohol before applying.

[HaroldMHedge]

[QUOTE=donbecker1234;10875540]Thanks for the link Harold.

I read that part of the thread but wasn't able to discern how to compare my plan of using Loctite 574 as opposed to Threebond 1184.

Do you have any information for that comparison? ...... [I'm/QUOTE]

Sorry but I'm trying to understand why to use the different sealants myself.

[Walt Fricke]

By and large, I think it easy to overthink this sealant question. Some sorts of sealants appear to be wrong for this or that application. A number are adequate. Some hypothetical best isn't really needed.

The most critical seal is the case halves, closely followed by the head to cam carrier seal. The rest can be dealt with if they fail - take off the leaking cover and redo things. PITA, sure, but not like splitting the case or removing the cam carriers. And Porsche just used gaskets for those.

[Flat6pac]

I use the 574 low on the cover gasket because, parked the oil level rises and I am trying to prevent leaks. Also, low on the chain box to case gaskets.
Three bond is too thick and skins over too quickly for my liking.
Bruce

[911pcars]

Some gasket sealers are so aggressive that it makes cover disassembly difficult as well as removing old sealer.

It's been widely suggested to avoid using silicone-based gasket sealers due to the chance of silicone blobs breaking free and clogging oil passages. Some popular Porsche case sealers are silicone-based, not just the oft-criticized Permatex RTV blue stuff. Read their Material Safety Data Sheets (MSDS) to confirm.

If using a gasket sealer, search for a non-silicone-based product.

Here's one link:
https://www.thedrive.com/reviews/31242/best-gasket-sealer

Sherwood