Copper Spray and OEM Head Gasket

[mkIIIman089]

I know it's been covered before, but I have not seen anyone mention the following so better safe than sorry:

Out of the box the OEM gasket seems to have some sort of "grippy" coating already on it, as either part of the manufacturing process or as a sealing agent of some sort. Does anyone have any info as to what the grippyness is from, or if any unfavorable interaction may occur between the solvents in the copper spray and this coating?

Thanks.

 

[radiod]

You read the sticky yet?

http://www.supramania.com/forums/showthread.php?t=29335

Covers it pretty well IMO.

EDIT: Just saw this thread was for an OEM HG, not MHG...my bad. Feel free to disregard the above, but it's still not a bad read if you're looking at MHG stuff

Honestly why would they make a gasket that wouldn't seal properly though? If you're doing everything right and by the book, you should haven't any sealing issues using a new gasket.

 

[mkIIIman089]

It doesn't cover it at all, considering jdub himself has said he's used copper spray on OEM headgaskets in the past. In fact the basis of my question stemmed from that thread, and not knowing if the OEM has always had a grippy coating on it out of the box.

 

[IJ.]

They come with a coating of hitack sealer much like using GM headbolt sealer (old school thing)

 

[mkIIIman089]

So is it a go or no go in your opinion? The question comes up because I'm trying to do what I can with less than ideal conditions, and want to give the best chance of filling any minor imperfections that may exist in the head and/or block.

 

[IJ.]

"Should" be fine to use as is Colin, if it can't seal the imperfections nothing else you do will have any chance.

Main area of concern is under the fire rings as that's where most leaking HG's start.

 

[mkIIIman089]

Gotcha, thanks! Great help as always Ian.

 

[IJ.]

Very welcome Col!

If you're really freaked out you could grab a can of the GM headbolt sealer and test it on a corner of the gasket to see if it's compatible with the Toyota goo, leave it sit a couple of hours if it doesn't bubble up/turn to slime you could then give around the water and oil passages on the head/block a coat let it tack off then do the install.

 

[mkIIIman089]

OK, I'm giving it *some* boost with ARP studs I asked about a little while back. (undercut were exactly the same price so I went with them, BTW :dunno If the Toyota goo is designed to help seal, as I suspected it may, it's probably an unnecessary hassle to add more to it. They've applied a pretty good coat of it as well, as tested by the industry standard finger nail check.

 

[grimreaper]

^ i like that, some one managed to get power from an oem hg, or at least good amounts of boost for a few years!... must be the fairy dust (or tune)

 

[mkIIIman089]

I have plenty of confidence in the stock head gasket design of today with ARPs and the higher torque. Especially with new or properly machined parts.

My car was on it's 2nd one already, done by Toyota in 1993; so I was basically waiting for it and as a result I caught it loooong before most on here do.

 

[grimreaper]

what where your first signs?

 

[mkIIIman089]

After the engine was completely warmed up (oil temp 80+) I'd see brief swings on my greddy temp gauge that looked like air bubbles. Also I noticed the cooling system had lost its ability to expel air and maintain a 100% full fluid level, could never pull the last 1/2in or so back from the surge tank. Previously I could always open the rad and the level would be right on the cap.

No stock instrument showed any abnormality what-so-ever.

 

[grimreaper]

what where your first signs?