Valve Cover Leaks

[Frank C.]

I have developed some minor leaks in the side of my valve cover. They are associated with some of the spot-welds that hold on a metal plate on the inside of the cover. I have two of them and they are literally pin-holes that dip out when I take the car for a longer run.

The questions are, has anyone experienced this and, if so, what is the best fix? I am thinking about sanding the outside of the cover and putting a thin layer of high temperature epoxy on. Then sand and repaint.

As always, I will appreciate any suggestions ...

Frank

 

[Randy Forbes]

I'd braze (or even solder) the holes closed, but that's just me.

With thorough preparation, the epoxy should hold for a while, if not indefinitely.

 

[Frank C.]

Thanks Randy,
Actually I considered the brazing option too but Id be concerned with solder holding up under the temperature extremes. I was also wondering if the metal was so saturated with oil that the brazing would hold ... I'm not a brazing expert!

 

[BobFrisby]

I wouldn't worry about temperature. Surely a valve cover wouldn't ever get above coolant temp, 220F or so ---

 

[Johnny]

I recall a similar thread on this same subject not to long ago. Most commented on the cause for oil leaking in that location. If you have worn tappets they throw excess oil up into the cover. Might want to check that out.

 

[BoyRacer]

The best way to fix the pin holes is to TIG weld the spots and grind off whatever bit of the weld stands proud. TIG welding is like performing surgery on a small job like this.
And, it is not worn tappets -- but - worn rocker bushings that allow the oil to spew all over the place.

 

[TimK]

My experience was a worn rocker shaft (the bottom surface of the shaft wore considerably. The fix was a new rocker shaft and new bushings. There should be no oil spewing around with these fixes in place.

 

[Frank C.]

It looks like some sort of welding is the best solution to my pin hole problem,I just have to get some help from a friend who has the equipment. As for the issue of worn parts causing the oil to "spew" everywhere, I'll look into that too.

Thanks for the advice and help.

 

[Cottontop]

By far the "easiest" solution that you can do by yourself is to solder fill the holes (from the outside), sand off the excess solder, prime, and paint.

The easiest solder for you to get your hands on is, electronic use, 63/37 alloy that melts at 361oF.

Plumbing use, 60/40 alloy melts at a 370oF.

Both alloys should be available at Lowes or Home Depot.

The melting point of either alloy is far above any temperature that your valve cover will ever see.

Use acid core flux (from the plumbing department) and a propane torch. The heat from the torch will dispatch any residual oil so the solder should flow smoothly and evenly.

Of course, brazing or welding is also good if you have the equipment handy.

Tim

 

[Legal Bill]

I'm of two minds about this thread.

1. Another great, informative thread with plenty of good advice and information.

2. Another problem I can look forward to when I start driving my Healey this year.

 

[Frank C.]

Thanks, I think I'll go the solder route, I have lots of it available. Now if I can only find my propane torch ...

 

[Steve Huneck]

If you haven't found your propane torch yet...I had some valve cover leaks which were caused by a worn rocker shaft. Oil should leak out of the holes in the rocker shaft, not squirt. On my car I could see the problem by just peeking under the oil fill cap. British Car Specialist had a replacement assembly that fixed the problem.

 

[Frank C.]

Thanks to all. I did find my propane torch (which was out of gas) but borrowed one from a friend to do the job. All seemed to go well but I'll have to take the car on a run to see if the oil is contained. With 3-5 inches of snow predicted for today, it will probably have to wait a little.

Thanks again,