Valve Spring Seat Replacement

BrokeMyCar · 09-30-2006, 10:26 PM

Hi folks,

I have reason to suspect one of my valve spring seats - is there a way to check/replace them without an engine drop?

Thanks,

Babak

82 SC

john walker's workshop · 10-01-2006, 08:49 AM

what do you suspect? the only damaged spring seats i've ever seen resulted from a broken valve spring that went unfixed for too long. they can also tear up the top of the valve guide.

BrokeMyCar · 10-01-2006, 08:59 AM

A while ago we pulled the lip of a seat out of the oil (image below) while trying to troubleshoot what ended up being a tensioner problem. Since it was the lip we figured it was probably ok, but last night one of the cylinders on the left sounded markedly different. I did a valve-adjust a couple months ago and no head-stud problems then.

Maybe it is a whole spring that's broken. I was going to do some exploratory surgery today, but I need to read up some first. After removing the valve covers is there a way to feel for spring action? I worry that manually turning over the engine won't reproduce the sound.

Thanks,

Babak

john walker's workshop · 10:19 AM

test each spring at TDC for that cylinder by pushing the rocker in against it real firmly with your thumb and forefinger. if you can move it by hand, it's busted. typical of SC intake springs for some reason, just do the intakes for now. no oil removal needed for those. seeing that seat piece, i think you will find one. there is a tool to replace it with the engine in the car, but the forward cylinders are harder to get to, so the engine may have to come out. hopefully the top of the guide is still ok.

BrokeMyCar · 10-01-2006, 02:40 PM

Thanks for the tip John - I opened up the left intake valve cover (where the sound was coming from) and found the retainer nut for the adjuster of cylinder #1 had fallen off, and the adjuster was wide open! I readjusted that valve (replacing the retainer), then checked all the springs on that side and they seemed solid.

That certainly does explain the sound - valve chatter in the worst way. I can't think of anything else to check before starting her up. On a side note, think I can drive around with the old valve gasket (2 months old) until the new one comes? It looked clean...

Thanks,

Babak

john walker's workshop · 10-01-2006, 02:59 PM

that doesn't explain the spring seat lip. they don't just break off for no reason. pull the other cover. you need to give all the springs a hard push to check them. wimpy won't do it.

BrokeMyCar · 10-03-2006, 05:20 PM

I've now checked all six intakes - the springs don't yield. Right after we found that rim (about 8 months ago) a compression test was done with no indication of trouble. Unfortunately I don't have the numbers.

I think I'll drive her for a bit, listening carefully. Next valve adjust I'll give the lowers a good push.

As an aside, I decided to try a clutch adjustment and had all sorts of trouble - until I realized that my car's missing the spring that attaches to the small arm! Ordered yesterday, installing tomorrow or Thursday.

Babak