Head gasket thickness

[yetta]

1990 e30 320i m20 My head gasket is leaking oil again. I had the head rescimmed with a new gasket. I have read the best gasket make to fit is the Elring, the supplier shows 2 thicknesses 2.08 and 1.88 which should I buy. Its definately not the cam oil seal.

[DanThe]

Depends how much material has been removed from the head, they should be able to tell you this if they have skimmed it

[yetta]

Would fitting the thicker gasket make any noticeable difference, as I don`t know any history before I bought it with 93,230 miles on the clock in year 2,000. It did seep a little oil from the front of the head then with several attempts by the garage to fix it saying it was front cam oil seal. since then I replaced the gasket after the head skim myself probably with the rienz gasket hence why it still weeps oil. Thanks

[HJ1981]

Is it leaking oil from the front of the head? specifically where the at/near cylinder no.1?

The Victor Reinz gasket is known to cause leaks, the PO used it and it appeared to be either the front valve cover gasket or camshaft o-ring, replacing those never fixed the issue till i replaced the head gasket with the standard size Elring brand one (with new BMW bolts and washers). I also found out, that all 12 head bolts were not even torqued down properly. Reading the manual of 30 NM + 90 degrees + 90 degrees, i expected those bolts to be on pretty tightly, all 12 bolts came off with as if they were torqued down to 10NM, barely any force was used to get them off.

Fitting a thicker gasket would raise the compression a bit, as DanThe mentioned it should be used depending on how much material is on the head itself first.

You said you had the head re skimmed, question is was it that very light skim that just ensures the surface is clean and flat? Or was it due to a warped head that required machining to be flat?

[flybynite]

You can tell how much has been taken off a head by the dimples/divots in the bottom face of the head, I am sure the 731 has them the same as the 885

There are also published head heights, 731 is the same as 885 as in 125.1mm standard 124.7mm minimum after skimming

If there is any uncertainty, use the thicker gasket, even a clean-up skim would eat into the the clearance so loss of compression will not be huge.

Still best to find out what they did to the head

[yetta]

Thanks very much for the advice will have a better look when I take the head off, as I don`t want to have to do it again.

[yetta]

Sorry forgot to mention the skim was just because I stripped the head down and did it to be on the safe side. No warping found

[flybynite]

If it is just a cleaning skim on a standard 320i I think you would be fine with the standard gasket as it is not as critical for clearance as the High Compression 323i which has the same head.

Pure guesswork though because I would be measuring the head or finding out how much was taken off first.

[reggid]

I’d go the standard thickness