Head Gasket Leak

[DSpringer]

Again leaning on the infinite wisdom of LZOC forum-heads, I need advice on a head gasket leak.

 

I put the heads back on after a thorough cleaning, using Felpro gaskets I've had around since the 1980's. There were some signs of coolant leakage before I started but no wet stuff. Now I have drips where the head meets the block above the exhaust manifolds. Torqued to 50 lbs. The gaskets that came off were solid copper. The Felpros are composite with copper lining at the passages.

 

I can:

 

1. Throw in some Barsleak head gasket seal (e.g. band-aid approach)

2. Pull the heads and put them back on with gasket seal

3. Replace the gaskets with something more current

4. Have the heads milled

5. 3 + 4

6. Other suggestions?

 

Looking at much earlier posts it sounds like their might be newer copper-asbestos-copper gaskets with large water passages around.

[peecher]

I would do the 3+4. Modern Felpro gaskets have the correct size water passages.

[19tom40]

Remove the heads and check them with a steel straight edge in several places. Place the straight edge along the top, middle and bottom of the head and then diagonally in both directions. If you can get a 0.010 feeler gauge between the head and the straight edge, have the heads milled.

 

Use a thread chaser and light oil to clean the threads on the studs and wipe them dry. You can saw a vertical slot in a head nut and use that to clean the threads.

 

Use new gaskets and torque to the 50 ft-lbs in 4 steps. First tighten all nuts evenly to seat the head on the block, then torque to 25 ft-lbs in the sequence shown in the shop manual, do this twice to ensure that the head is seated. Nert torque to 40 ft-lbs and finally to the 50 ft-lbs.

[DSpringer]

Thanks, I'll do as you both suggested. New gasket set is on its way. 

 

That's pretty much how I torqued the heads and the threads on the studs are clean. I also oiled the nuts before I put them on.

[19tom40]

The torque specifications are for dry threads. when you get the new gaskets, do not oil the threads on the studs or nuts. Do not try to remove the oil with anything other than a dry rag. It will leave the correct amount of lube on the threads.

Edited September 13, 2015 by 19tom40 (see edit history)