checking for valve leaks

[tektic]

So I removed my cams, turned the head over and sprayed brake cleaner on the valves.

Every one leaked. Is it possible that enough carbon is in there after 1200 miles to keep every valve from seating?
Or do I have to clean it before testing it?

 

[FlyingEagle]

Try it with water overnight.

Remove valve and have a look.

Best to know first hand if you suspect burnt seats or carbon issues.

 

[362Ryan]

Sounds like bad seats.
Did you get them cut for the rebuild? Did you lap the valves too?

 

[tektic]

I had both done yes.

 

[362Ryan]

Std or Over sized valves?

Sounds like a bad cut to me.

 

[tektic]

1mm over

 

[362Ryan]

And they cut the seats for that?
I have a friend that had over sized and the shop still cut the seats for std and all of them leaked.

 

[ktmrider]

Quoting tektic:
So I removed my cams, turned the head over and sprayed brake cleaner on the valves.

Every one leaked. Is it possible that enough carbon is in there after 1200 miles to keep every valve from seating?
Or do I have to clean it before testing it?

You made a comment in your "Wet Headgasket" thread about a possible valve/piston contact event at startup. Could easily explain the leaks if I understand that other post correctly ( slightly bent valves ).

 

[tektic]

Yes, thats why I was checking in the first place. however there was no indication of exhaust valve contact and they leak also. thats why I though I might be doing the test wrong.

 

[tektic]

They did cut the seats larger. if they were metric and not standard sized I don't know. I don't even know if that's a thing. I know it would have been nice if he made the throat cut a little wider.

 

[prove_it]

Tap the valves lightly with a hammer to get the valve to move a bit and see if it reseats before condemning the seal. Sometimes it takes the force of the spring closing the valve to seat fully.


Was this a single, 3, or 5 angle valve job?