928mac

Hello Gentlemen;

Me again with another what's the common practice Question.

So today I got off my seat and went to work cleaning so that I could install at least one of the heads. Didn't happen, still cleaning.

My question is, is it common practice to use a sealer of some type on the block and head to help keep it sealed?

I ask because what ever was left on there was nasty hard, like carbon hard, and some kind of lacer looking or varnish looking coating on the head.

Normally I always put a head gasket on dry and if it would need sealer then maybe it should be machined.
But as I have found out, the 928 is not normal.

So ... what's on the heads besides old gasket?
and
do you guys in the shops put the gaskets on dry, without gasket prep?

Thanks for the time and your much appreciated knowledge.

blown 87

Machine the heads.
Just enough to clean it up on a surface grinder, do not let anybody use a belt on it.

blown 87

Oh, the VR head gaskets go on dry.

AO

I used a razor blade held perpendicular to the head and scraped it clean. No risk of gouging the head.

928mac

Well after bout 4 hours this is how it turned out.

I wish there was a head shop in town Greg.



I followed up with a rubber cleaning tool



and a brass wire cone on the drill for the valve chambers

blown 87

I wish there was one also, cause if you used that Roloc pad you are going to need one.
And yes, i know white is for AL, it still should never, ever be used on a head or a block, ever.

928mac

I'm going to find a shop tuesday that has a good reputation for milling heads.

GregBBRD

Great idea!

928mac

What is the cc of a un-milled stock R3 head.
You can only take so much off and since I do not know this cars history, I should compare where I am at.

Agreed

dr bob

The WSM gives milling limits, defined as differences in height on a wear pad IIRC.

The operation you are looking for is just the tiniest skim, a thousandth or two at best. This will ensure that the head is flat, and that any small imperfections will disappear enough that the gaskets will seal on the new surface. Those scuff marks from the wheel say that metal was moved around some, but not much beyond the surface scratches at least from the pics you show. Stiil, safest to get it perfectly flat and smooth.

Dennis Wilson

Oops, Dr Bob beat me to it.

If the 32 valve heads are like the 16 valves, there are blocks on each end of the head that, when measured and compared to the factory height in the WSM, will tell you how much the head has been previously machined.

Dennis

Speedtoys

The gasket would fizz like soda pop..right?

jeff spahn

Just cause I am stupid I'll ask anyway. Could a scotch brite wheel be used on a dremel?

928mac

The answer would be no Jeff and as explained to me by one of the shop owners is that he had redo some engines that one of his late mechanics used these type of tools on.

The squared edges around the ports gets rounded off and the fluids or pressure wedge past the gaskets causing a leak.

Hence REDO.

Brad

Imo000

I've used a gasket scraper, not the razor blade type above, and it worked great. Re surfacing is the absolute best solution but cleaning them up well is, to me, another viable option.