jim21070 2 Posted January 17, 2007 I'm refurbishing my spare head and today I was lucky enough to secure a dip in an ultrasonic bath just before it was due its routine fluid change The head has come up nice and it has saved a lot of tedious cleaning work. During a bit of detailing work I noticed that there are steel shims between the head and the valve springs. Never knew that I appear to have seven of them but the last one seems to be missing and to me, comparing score marks, it looks like it has never been there. Or, at least, not in a long time. I know it was not lost in the bath as I was the one who drained it and wiped the sh!te out of it. I would have spotted the shim. Are they essential? I don't want to rebuild the head and then find all my work undone because I missed this shim. Share this post Link to post Share on other sites
Daxed 7 Posted January 17, 2007 Do you mean the shim that sits between the bucket and the valve stem? If so then yes essential. Varying the thickness of the shim alters the valve clearance. Share this post Link to post Share on other sites
jim21070 2 Posted January 17, 2007 Do you mean the shim that sits between the bucket and the valve stem? If so then yes essential. Varying the thickness of the shim alters the valve clearance. No, no, I know all about those shims The shim I'm meaning is the one that sits between the spring and the spring-bed on the base of the head. This is a thin steel shim the same diamater as a valve spring and appears to give the spring a steel bed to lie on rather than seating directly onto the alloy of the head. Share this post Link to post Share on other sites
Ahl 4 Posted January 17, 2007 I don't know if they are essential, but they will be there for a reason. Try the wanted section, somebodies bound to have one spare from an old head. Share this post Link to post Share on other sites
Sie 0 Posted January 17, 2007 (edited) They are there to stop the spring wearing into the head and are called spring seats . If you get stuck for one P.M me and I will send you one in the post . Edited January 17, 2007 by Sie Share this post Link to post Share on other sites
jim21070 2 Posted January 18, 2007 They are there to stop the spring wearing into the head and are called spring seats . If you get stuck for one P.M me and I will send you one in the post . Thanks Sie PM sent! Share this post Link to post Share on other sites
lagonda 42 Posted January 18, 2007 This is interesting. When I dismantled my original (cracked) 1.6 head, I found one shim only, & that was buckled because it seemed it couldn't cope with the pressure/movement of the valve spring. I assumed someone had added it at some point in the car's history too make up for a slightly tired spring. None of the other seven had shims, furthermore, no sign of damage or wear to the seating areas. The replacement head was from a 1.9 & that had no shims at all, & no sign that it needed them. Perhaps shims were fitted to early/late cars only, or to specific engine types? OOO ERR! Share this post Link to post Share on other sites
jim21070 2 Posted January 18, 2007 Indeed, most curious... The head I'm doing was originally from a very late 309 GTi Goodwood, replaced only because the stem seals had gone. They are incredibly thin and I only spotted them when blasting the head with an airline after it came out of the bath. They started dancing Share this post Link to post Share on other sites
