Cyl Head/Valve Job Repair

[PRH]

With the spring removed from the seal, it’s fairly pliable.

After the seal has been slid up off the guide…..With a little drop of oil on the valve in the groove area and some slight wiggling of the seal, they just slip right off.

 

[Woody500]

Didn't you post that you just want to shim some springs? If so then you don't have to even remove the valve stem seals, or did I miss something.

 

[Ironmike]

Buy one new head.

This. I wouldn't run that head in a beater. Sorry but I think someone really screwed up that job. I guess you COULD have a reputable shop repair it but would you ever trust it?

 

[mopowers]

Didn't you post that you just want to shim some springs? If so then you don't have to even remove the valve stem seals, or did I miss something.

The shims and locators are under the seals.

 

[mopowers]

Well, I'm certainly glad I'm double checking everything on these heads. The installed heights ranged from 1.950" to 1.985".

I bought a spring checker and rigged up a checking station at my drill press with a stop right at 1.950". It ended up fairly repeatable too, so now I just need to buy some shims to get the pressures closer to 130 lbs on the seat.

I just wish I didn't have to buy another new set of valve seals.

I also measured the volumes of several combustion chambers. The damaged one is a bit larger than the others (61.3 cc vs. 59.5 cc for all others). This will work out okay though because the piston for that hole is the highest (by a few thousandths), so the difference won't be a big deal.

 

[mopowers]

Question for you guys though. I noticed some of the valve locks have more up/down play in the valve groove than others. I'd assume they should be pretty snug. Several of them are actually. Should I just replace them while I'm at it? Other than that little bit of up/down slop, they seem to fit well. Do these get beat up after a while? Maybe this is partly responsible for the the increased installed heights?

 

[Newbomb Turk]

Question for you guys though. I noticed some of the valve locks have more up/down play in the valve groove than others. I'd assume they should be pretty snug. Several of them are actually. Should I just replace them while I'm at it? Other than that little bit of up/down slop, they seem to fit well. Do these get beat up after a while? Maybe this is partly responsible for the the increased installed heights?

View attachment 1716413556

Make sure the land on the lock isnt thinned out. Your groove looks very good so it’s probably in the lock.

To verify this, find a lock that isnt loose and try it on every valve. If it’s not loose on every valve then you know it’s in the lock.

 

[mopowers]

Make sure the land on the lock isnt thinned out. Your groove looks very good so it’s probably in the lock.

To verify this, find a lock that isnt loose and try it on every valve. If it’s not loose on every valve then you know it’s in the lock.

Thank you. I just went out and double checked. All of the locks look good and the lands are not not thinned at all. They all match the couple that had been replaced - they just have some movement up and down in the groove.

The couple that were snug actually had tiny burrs that I was able to file off slightly. Now they all have a slight up-down slop so I'm pretty sure new ones would not be any better. It's just weird to me that they don't make these locks with a wider land to fill the groove fully.

There are a few brand new valves and the grooves on those valve look exactly like the others, so the valves are all good.