/6 valve cover leak......still Options

[Dr Evil]

So I got the new silicon covered valve cover gaskets and put them on last time I ran the car hoping that this would solve the oil incontenance my engine is suffereing.....nope. Then I recalled that I may have been expecting a bit too much from these new fangled gaskets. My old valve cover has some corrosion on the mating surface that is potentially the cause, or at least an exacerbating factor of this leak. That plus the tooling marks on the head probably did it in. Thus, I just scored a good deal on some turbo valve covers (they realy have come down in price for new, though) and hope to have them in by Fri.

Some thoughts about hte other part of this problem, the mating surface of the cam towers.
Q: Could I fill in any tooling marks with a filler of some sort and sand smooth? ex; quick steel, jb weld, etc.

So long as this compound is not heat sensitive and can withstand oil I think it would work.

Comments?

[Aaron Cox]

alright,......how bad did you gouge the surface?

[Cap'n Krusty]

If you VERY CAREFULLY dress the surfaces with a large flat file, getting any burrs out, clean it with brake cleaner of laquer thinner, over fill the holes with JB Weld, and again file it flat, it should work. It's a factory authorized repair for pitting in BMW heads, and I do it with Wasserboxer heads all the time. Works well, within reason. So Called "Turbo" valve covers will require some pretty extensive machining to achieve clearance at the suspension console. Early aluminum SC lower covers might be better, assuming they're flat. Are you sure it's the covers and not the rocker shafts? The Cap'n

[drgchapman]

I just had my 3.2 put into my car. The race shop that did the final details on the engine and linkages (Rothsport) said that the silicone gaskets are no good as they "creep out" of the mating surfaces over time. He recommended the black graphite and paper gaskets as the best ones.

For what it's worth.

Gary

[Dr Evil]

Krusty,
that is exactly what I was thinking. I am glad to know it is something that is already done. I am not 100% that it is not the rocker shaft. I may know more later today when I get in there. either way I needed a new cover. I gave the shop the gaskets for the rocker shafts (upgrade, not stock on my car I know) so I am not feeling like the shaft is the problem (fingers crossed). I thought the turbo covers were the big upgrade. I know I will have to machine of a little to get them to fit...I had to do it to these too. Also, I could not find a source for the OE old style covers. The only ones offered now are the turbos.

Aaron, I didn't gouge the surfaces. It kinda makes me mad as I know I didn't.

Gary, I had the ones you speak of first and they were way worse in my case. The new ones are doing beter, but I still have a constant drip.

[lapuwali]

I wouldn't say the machining required to get the Turbo valve covers to work in a 914 is "extensive", but it's not zero.

When you actually get the engine in the car, the first thing you should do it try to remove the exhaust valve covers. You'll likely find that you can't get them off, as they won't clear the trailing arm mount. You can machine off the ribs in the bad area, or you can use bolts instead of studs and nuts to hold on the cover. The bolt idea almost requires you to fit helicoils/timeserts where the studs went, as the cast Al cambox won't like you to remove/refit bolts regularly to do the valves (why studs are used). In any case, you'll be dropping the engine again to fix the problem...

[Dr Evil]

I didnt have to drop the engine the other SEVERAL (due to oil leak) times that I have had to remove the valve covers recently. Oddly enough, I did have to remove the oil line on the one side and then bend the outlet out a little. I think my engine mount puts my engine a little forward and my oil cooler adaptor mod put the damn fitting about an inch closer than it could have been. I'll just measure the original covers for clearance and match the specs to the new ones.

Thanks for the info and idea about the bolts, but no way do I want to start helicoiling and such.....I hope I do not have to change my tune about that later.

Hey, for the JB Weld should I only use the long time to dry stuff (original) or would the JB quick work as well (I have some already)?

[Dr Evil]

I think I will take pics so I can give you all a better understanding of my particular dimentional situation.

[lapuwali]

The tall ribs on the Turbo valve covers pretty much prevent removing the covers with studs in place, which is what I meant. If you had Turbo valve covers before, then perhaps they've already been "relieved". If you didn't, then compare them to the old covers (which have much shorter ribs).

If you can remove completely stock Turbo covers on your car with all the studs in place, your trailing arm ears aren't in the same place they were on my '73.

[Dr Evil]

Ah, gotcha. No, I knew going in that I would have to remove and modify some ont he ribs and material. No worries there. Ya, the old ones ribs are almost non existent.

[Root_Werks]

Evil one,

Did you set the valve cover on a flat surface yet? Had a couple cars come to me with leaks and the lower covers were "warped".

Typically you should be able to get a non leaking seal with the standard thicker graphite gaskets. There is some manual out there that says to torque the nuts down to something like 6lbs which just doesn't cut it. They need 40-45lbs torqued from the inside out in the typical cross pattern.

If you have a 4 1/2 grinder and want to put on turbo valve covers. Grind away until you can put the cover on with the engine in the car. Easy. Done a few, takes about 15 minutes to do both and you only take off just what you need.

[Aaron Cox]

40-45 lbs?

seems alot? what size thread are they?

[Cap'n Krusty]

40-45 lbs?

seems alot? what size thread are they?

I use 18, which is just a little more than the 15 specified. I wouldn't use the rapid set JB weld. As with other epoxies, what you get in convenience, you lose in permanence. It needs to dry 24 hours before you can file it. The Cap'n

[Dr Evil]

They are 8mm studs.

Dan, yup, pretty much what I was a figgerin.

Krusty, I figgerd that as well. Just can't cut corners.

As for the rocker shaft, it does not seem that any are leaking (yay). the corrosion on the valve cover was right where the leak was. It is minor pitting corrosion, but it seems to have been enough to help/cause the leak.

I will check the trueness of the old one (as mannnnnnny of you have suggested) tomarrow.

[Racing914six]

This is my $0.015 worth.

To get the valve covers to stop leaking.

1. Remove old covers and media blast them if they are the 930 type, else buy 930 type

2. Remove studs that hold on the lower valve cover

3. Clean cam tower surface. Lightly sand any tuff spots

3a. Adjust valves if needed

4. Install new studs. Note some studs go through the cam tower. Those studs require orange type loctite sealer. The rest use blue loctite.

5. Install new gaskets.

6. Install 930 lower valve covers.

7. Install new alum crush washers and 8mm nylon locking nuts.

8. Lower car and enjoy favorite beverage

[Brando]

Definitely check if your covers are warped. Worst case scenario the cam towers are warped. It happens on 911 SCs that have had broken head studs and were still driven too long. Seen it twice on abused 911s at the shop.

[Dr Evil]

This engine has 0 miles on it. I rebuilt the bottom end and had a shop finish the top end so it is most liekly the shitty valve cover. I have new studs as well so no worries there. Everything had been chased/replaced and specked (supposedly) and so for ai have no real reason to believe otherwise. Other than my shitty valve cover which is the likely candidate.

I don't even own a straight edge....looks liek I am gonna have to get one tomarrow (IMG:style_emoticons/default/biggrin.gif) I just want to know, but the missing material from the corrsion was right where the leak was.

[Allan]

40-45 lbs?

seems alot? what size thread are they?

(IMG:style_emoticons/default/agree.gif) That's a ton of torque on valve covers.



Hmmm, I wonder..... (IMG:style_emoticons/default/dry.gif)

[iamchappy]

Silicone valve cover gaskets should be torqued to about 8lbs or less, they leak and will cut if you over torque them they need very, very little tightening. 45 sounds like a lot to me on the paper gaskets there only holding a cover on, I personally would tighten no more than 15.

[Root_Werks]

40-45 lbs?

seems alot? what size thread are they?

That's only if they are giving you problems, sorry, I should have been more clear on that. Studs are 6mm. It is a lot of torque for a vavle cover, but if you have one that is slightly bent (Warped), it's about the only way to get it to seal without getting a new one or truing up the old one.

Evil one, set your valve cover on the kitchen table and see if it rocks back and forth at all. Laymens test, but will give you a quick and dirty answer.