So, I'm getting ready to put the heads on...manual says, referring to the gaskets, "Must be fitted dry" There's a bit of water damage to the decks at the gallery. I'm thinkling a touch of permatex aviation cement might not be a bad thing at those points...maybe a thin bead of silicon...Anyone have any thoughts on the topic? One deck is preped, I'm going to prep the other now. So an ASAP reply would be much appreciated. (Kinda like "Dragnet: no speculation..."only the facts...")
Thanks

 

well, as the heads and block heat up and cool down they expand and contract at slightly different rates and need to slide on the gasket as they do so. The primary cause of head gasket failure is when the mating surfaces stick to the gasket for whatever reason and essentially pull it apart at a microscopic level (it's called "scrubbing") resulting in loss of sealing pressure at those points. So, no, I wouldn't put anything at all on it. That's what they mean by "dry".

 

There's a bit of water damage to the decks at the gallery.

This would concern me. Exactly what are you talking about? Is it going to affect mating/seating of those surfaces?

 

I'll be the first to admit that I'm not a metallugist. It seems that would be a greate problem when mating aluminum heads to an iron block, otherwise, Im have always ASSUMED that, the heads and block are the same alloy, hence the same rate of thermal expansion...Granted localized heating would account for varying degrees of expansion of different componenets at different locations.
All that being said, 1) i wasn't considering using any sealant over the entire mating surface, just at the pitted area and 2) there's just gotta be sumthin ROTTEN in Scotland!!!... or ENGLAND, in this case!!!
Here we have a little bitty V8, coupled to a large radiator, did I mention( though it's rhetoric) the things ALUMINUM, (which, also goes without saying...TRANFERS HEAT READILY...) And it's got a low compression ratio!!! Only the English could make this thing OVERHEAT!!! i knew a guy in the '80's that raced one in a TR6, it was the bomb! I don't recall the CR, but I guarantee one thing, it did not have dished pistons and a lawn mower cam!
Thee is something really wrong with this picture!
First thing I'm doing after finishing assembly, tomorrow, is REMOVE that friclin' insulation from the hood and see if I can find someone locally to vent the hood for me. Did I mention that the SAI, must stand for STUPID Air ( as in HOT air...) is NOT going back on!
Another solution I want to look into is finding/having a chip burnt for a 160cegree thermostat.
This is rediculous, here we have a beautiful vehicle, that quite frankly, I'm afraid to drive!
You can't tell when it's overheating because the guage is improperly designed...what MORONS thought this was a good idea...?
That's my rant for the night>>>
So, MERRY CHRISTMAS, HAPPY HANUKKAH and HAPPY NEW YEARS!!!

 

I've run 160 and 180 stat with no noticed change in mpg. Not much heat with the 160. Big change was getting rad flushed and rodded out. Scanner says I run at 180 -183 at 50 mph. But since you have SAI, you have a D2 (here in the D1 post), so you would be looking at the in-line stat mod.