Headgasket job; is there a way to I.D. the current size??

[Sac73'02]

Before the head is removed? I know for certain that the motor isn't original and was completely gone through. I don't know if an over bore was performed. In the interest of making this job A-to-B, is there a way for me to I.D. ahead of time so that I can order and have it to hand when I undertake this task? Also, was the same head gasket called for in all M10s? I have one from a late 70s 320i. Thanks!

[Rigmaster]

Before the head is removed? I know for certain that the motor isn't original and was completely gone through. I don't know if an over bore was performed. In the interest of making this job A-to-B, is there a way for me to I.D. ahead of time so that I can order and have it to hand when I undertake this task? Also, was the same head gasket called for in all M10s? I have one from a late 70s 320i. Thanks!

Quick answer- No.

Assuming you're asking if you can tell what size (diameter) pistons you have in the engine- you cannot tell without pulling the head. Once you pull the head then you can clean off the top of a piston to see the size stamped there. The 2.0l from a 77-79 320i will use the same head gasket as the 2002- though the head gasket "set" will include different gaskets for things such as intake, FI, etc- so just get a 2002 head gasket set unless you are running 320i FI.

Bret.

[winstontj]

To the best of my knowlege there is only one size head gasket unless a special one was used. I've attached the list of part numbers I started... it isn't all years but I got bored when they were all the same. There is a stock & a thicker gasket (if you've had your head planed or block decked). Other than that you have to check with the PO.

Hope that helps!

Couldn't add an excel spreadsheet as an attachment. Just go to www.realoem.com They're all the same from 68 to end of the E30 M10 in 84

[Sac73'02]

that I should be able to use just the standard replacement gasket even if I find that the motor had been bored once over? I did see the two gaskets wherein one is .3mm thicker than standard. I might be stating the obvious here but the head gasket isn't offered in sizes in relation to standard overbored sizes and that it's not as critical as crank or rod bearings when those areas are machined. So on the head gasket; unless I find out that the PO had installed anything other than standard or once over pistons, the standard head gasket replacement size will suffice, yes? Thanks again!

[winstontj]

The standard once over bore isn't the issue... It's so small it's negligable really. The real issue would be if the deck of the block has been milled. Normally pistons don't (correct me if I'm wrong guys) ever protrude out of the block. If there has been (bad) work done and your pistons protrude out of the block AND the cylinders have been overbored, you may have an interferance issue. You'll know when you get the head off though. Check to see how far up the pistons go & look at the head gasket. You'll be able to tell right away if it's not a stock gasket.