Engine rebuild

What kind of gaskets did you use?Felpro Perma torqes?or a steel or copper gasket?If you used a steel or copper did you use any copper sealer?You can try some Bars Leak(the pellet type,not the small filings type).Its good stuff(used by Chrysler at the factory),but you will probably have to pull the head and check the surface.Good luck

I used FelPro PermaTorque.I thought about the BarsLeak, but would rather fix it right. Yep, sounds like I've got a project ahead of me. Was looking for motivation to pull the ZF and have it looked at anyhow. Don't think its ever been out, gotta get those bolts safety wired!

You have a nice winter project ahead, unless you wish to take a chance with Barrs Stop-Leak. This $3.00 tube from any auto parts store will plug up very small leaks until you can get around to a proper rebuild. Fel-Pro IMHO makes an excellent gasket so assuming you torqued the heads properly, to Boss 351 specs, something is wrong. Simply slapping another gasket on is not the way one fixes such a problem. The root cause must be found and this may be a warped or cracked head OR block. Incidently, check your oil pan as well- ethylene gycol present in the pan is very bad. Its not well known, but bearing babbit is soluable in hot ethylene glycol. It is quite possible to DISSOLVE your bearings if you continue to drive with a coolant leak down in the oil.

Is there something distinctive about the oil if it has antifreeze in it? Incidently, there was a white "cloud" coming out of the valve cover breathers after running for a few minutes, but no smoke from the exhaust.

If you have alot of water or antifreeze in your oil it will turn a muddy brown color.If you only have a little water mixed in its harder to find.Start with looking on your oil filler cap and your dipstick.Another way to tell is let the car sit a few days and pull the oil drain plug for a couple of seconds.Oil floats on water and the water will come out of the drain before the oil.good luck

Theres a simple chemical test that can be done to check for the presence of glycol in oil and it can be done on a small sample of oil- the car need not be present. If you live in or near a big city, such a place can be found in your Yellow Pages. Or, there are places that do this by mail-order.

I have a similar problem. Recently overheated a bit, and cylinder 7 and 8 showed 6:1 in CR versus 10.5:1 on all others. Tore the heads off, block and heads checked out for flatness. Bolted the pieces back together, used Fel-Pro composite gaskets and torqued to specs (55 to 75 to 110 pounds) and nothing. The compression is still off on the same cylinders. Any suggestions?

Zantin,
I'm assuming nothing of your knowledge or what you've tried since you mentioned little. (After tearing the engine back down to the cam, I recently found that my new SFI dampner was mismarked...so assume nothing.)

Did you check the leakdown or just pumping compression? Listen for where the air is leaking from. Carb/intake valve, Header/exh valve, Valve cover/rings.

Did you check for cracks? Head or block

Did you loosen the rockers and recheck?

Did you check "roundness" of the bores?

Had you noticed anything before the overheating, and what was the cause of overheating?

Any bubbles in your coolant, when the engine is running with the cap open (always cool engine first)?

EASY CHECK for water in oil: let oil into a milk jug and let set for a day, look for separation. I've spun a bearing like this before on a newish engine. If external and your just looking into the bay, are you sure that its not from the intake...hoping optimism.

[This message has been edited by Bleeds Blue (edited 12-17-2003).]

I just did a pumping test, and the oil in the cylinder trick to see if the rings are worn. I don't think it's the pistons, the engine looks pretty fresh but according to Murphy's Law it's probably a cracked block (although I didn't notice anything obvious when the heads were off). When time allows I will do a thorough investigation.
The heads were brought to a local speed shop and checked out OK. The compression is a little off on the right bank which indicates they need to be re-torqued and some research online revealed they are suppose to be to Boss specs (125 lbs/ft), slightly more than the book spec (95-105 lbs/ft).
It's amazing though that the compression is exactly to the decimal the same on the leaking cylinders as before "re-build".
Cause of overheating: faulty fan relays in stop and go traffic on the interstate.
Bubbles in the coolant!?! I had a virtual geyser in the engine compartment at operating temperature, but luckily there was no water in the oil when I drained it.
Question: How much does incorrect valve lash effect pumping pressure? (Grasping for straws here).


[This message has been edited by zantin351 (edited 12-19-2003).]

[This message has been edited by zantin351 (edited 12-19-2003).]