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Main Area => General GS500 Discussion => Topic started by: J_Walker on February 27, 2012, 03:38:52 PM

Title: Valve seat Bad...
Post by: J_Walker on February 27, 2012, 03:38:52 PM
So on my bad side [left side] I was going and putting in all new valves. once I pulled my intake valve, I looked closely and saw something.. The valve seat is oddly shaped, one side is bigger than the other! I got my valve compression tool, All new set of valves [all four] Valve grinding compound. waiting for my gasket set to come in any day now. Getting an New oil filter and oil As with 3/8th and 1/4th torque wrenches Saturday. but does this mean I have to take my thing to a shop? Or can I do something to correct it? its not horribly bad. in size compression Its about the difference between you pinky and index finger. [unless you have a really fat pinky.] :) Of course not to exact size. Just the size difference.

(http://i40.tinypic.com/1pc4uu.jpg)
Title: Re: Valve seat Bad...
Post by: BaltimoreGS on February 27, 2012, 04:54:19 PM
Hard to judge just by a picture but if lapping the valve doesn't get it to seat properly you either have to have a machine shop redo the seat or replace the head.

-Jessie
Title: Re: Valve seat Bad...
Post by: J_Walker on February 27, 2012, 08:20:10 PM
Quote from: BaltimoreGS on February 27, 2012, 04:54:19 PM
Hard to judge just by a picture but if lapping the valve doesn't get it to seat properly you either have to have a machine shop redo the seat or replace the head.

-Jessie

but if she seats fine, I will do another liquid test.. Than that should pretty much tell me if it needs to be machined?
Title: Re: Valve seat Bad...
Post by: BaltimoreGS on February 27, 2012, 08:33:55 PM
Yep.  If it doesn't seal it needs to be repaired or replaced.

-Jessie
Title: Re: Valve seat Bad...
Post by: J_Walker on February 27, 2012, 10:21:23 PM
So will this cause problems in the future?
Title: Re: Valve seat Bad...
Post by: twinrat on February 27, 2012, 11:07:09 PM
as long as you lap and get a good seal you will be fine.YOUR cause of the seat being wider on one side than the other is probably because the bore was slightly off centre at the factory. One thing to do before you lap it is to make sure the valve guide is not worn out.If it is then you need a new guide and have the seat cut with a seat cutter before lapping and centraly trued up in the throat of the valve seat.I noticed that you have soft fluffy carbon which is an indication of a rich mixture or running on low octane petrol and burning oil possibly,(the lower the octane the more oil in fuel)
Title: Re: Valve seat Bad...
Post by: J_Walker on February 28, 2012, 12:36:24 PM
Quote from: twinrat on February 27, 2012, 11:07:09 PM
as long as you lap and get a good seal you will be fine.YOUR cause of the seat being wider on one side than the other is probably because the bore was slightly off centre at the factory. One thing to do before you lap it is to make sure the valve guide is not worn out.If it is then you need a new guide and have the seat cut with a seat cutter before lapping and centraly trued up in the throat of the valve seat.I noticed that you have soft fluffy carbon which is an indication of a rich mixture or running on low octane petrol and burning oil possibly,(the lower the octane the more oil in fuel)

Actually its Carbon yes. I was "attempting" to clean it up.. but carb cleaner really don't do a whole lot, only way I can get that SOB carbon is wire brush it out. ITS REALLY IN THERE lol! so the carb cleaner is just sitting in there, I wiped it out already. looks dry again. Hard to get that stubborn carbon out. how do you know a valve guide is warn out? Just by looking? Or is there a way to measure it?
Title: Re: Valve seat Bad...
Post by: The Buddha on February 28, 2012, 01:19:46 PM
There is a spec for how much it can let the valve "wobble". In the manual. If its too tight, remember these will get up to ~5-600+ for intake, and maybe 7-800 exhaust, and you can easily have it bind when hot.
In a way the looser it is the more oil gets in there and the thing actually works fine.
Cool.
Buddha.
Title: Re: Valve seat Bad...
Post by: J_Walker on February 28, 2012, 01:36:12 PM
Never mind.
Title: Re: Valve seat Bad...
Post by: The Buddha on February 28, 2012, 02:46:47 PM
You have that kind that is a modified C clamp or the kind that looks like an impact driver.
The C clamp you basically need to keep the seat from getting out of the face of the clamp.
If its that impact driver kind - good luck, no clue what that is all about.
Cool.
Buddha.