Mike_72

I just had an exhaust valve guide changed by a reputable shop but I am starting to question their work. It felt like the new valve and guide have more clearance than the 30,000 mile guides. So today at work I measured everything out and here is what I found.

New valve stem diameter - 0.3136"

took measurements at ~1/4" intervals down the guide:

Top of guide
.3182" ------> 0.0046" clearance
.3160" ------> 0.0024" clearance
.3159" ------> 0.0023" clearance
.3158" ------> 0.0022" clearance
.3158" ------> 0.0022" clearance
.3159" ------> 0.0023" clearance
.3175" ------> 0.0039" clearance

I measured the next exhaust valve over (30,000 miles)

0.3155" give or take .0002" pretty much the whole length of the bore.

I also found a bunch of grooves around the circumference of the inside of the new guide, while the old guides are perfectly smooth.

Looking for anyone who may be able to shed some light on if this is a problem or not.

Mike_72

Here is a picture of the grooves I talked about

c6 batmobile

iTrader: (2)

Looks like they used something threaded to make the new guide.

Mike_72

I suspect they knurled an old guide and charged me for a new one, just looking for someone who had seen a knurled guide before to confirm it.

Richard@WCCH

iTrader: (3)

Some replacement cast iron guides are knurled out of the box. Hard to say if those are from the photo however .002" and some tenths clearance shouldn't cause an oiling problem providing the valve seal is new and installed properly even with the knurling groove.

Richard