Valve guide problem
#1
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Joined: Jun 2004
Posts: 1,144
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From: Sun Prairie, WI
I pulled my port exhuast manifold and valve cover to investigate a small oil leak. I then shone the light into the exhuast ports and found #4 port wet and had baked on oil. Upon further investigation I could see the bronze valve guide half way or better up the exhuast valve stem and the seal up under the valve retainer. Turning the motor over and watching verified the guide is moving with the valve. I did compression checks to see if a valve was bent, I had 165 to 170 on the whole bank.
What happened to the guide? Motor has less than 20 hrs since total rebuild. SS iconel valves/ bronze guides......
What happened to the guide? Motor has less than 20 hrs since total rebuild. SS iconel valves/ bronze guides......
#2
I pulled my port exhuast manifold and valve cover to investigate a small oil leak. I then shone the light into the exhuast ports and found #4 port wet and had baked on oil. Upon further investigation I could see the bronze valve guide half way or better up the exhuast valve stem and the seal up under the valve retainer. Turning the motor over and watching verified the guide is moving with the valve. I did compression checks to see if a valve was bent, I had 165 to 170 on the whole bank.
What happened to the guide? Motor has less than 20 hrs since total rebuild. SS iconel valves/ bronze guides......
What happened to the guide? Motor has less than 20 hrs since total rebuild. SS iconel valves/ bronze guides......
Was it a shouldered guide?
What was the clearance between the guide and valve?
What type of stem seal?
What was the O.D of the guide and the I.D. of the guide boss?
#3
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Joined: Jun 2004
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From: Sun Prairie, WI
can't answer many of your questions, as i didn't do the build. It was done by Goodwin Competition. They are the stock cast iron heads. I can also say the seals were not the umbrella type, they are p.c. valve seals
#4
I know of Todd, I know Steve M, owner of Comp. Products & Howards. Todd, is Steve's guy. I would take that back to Todd, and let him look at it, before you start getting on here looking for answers. Is he willing to look at it?
#5
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From: Sun Prairie, WI
Plan on it. Been working with Todd now for a year. I just came upon this problem today. I think i've been running it like this for awhile from the appearance of the exhuast port and valve stem. Don't know what would have happened if i didn't catch it. I'll be talkin to Todd tomorrow, but just wanted an idea of why this guide would have come out like that.
#6
Plan on it. Been working with Todd now for a year. I just came upon this problem today. I think i've been running it like this for awhile from the appearance of the exhuast port and valve stem. Don't know what would have happened if i didn't catch it. I'll be talkin to Todd tomorrow, but just wanted an idea of why this guide would have come out like that.
#7
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Joined: Jun 2004
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From: Sun Prairie, WI
I have seen valves stick in the guides, usually they bend the valve. The bore could have been to loose for the guide, high exhaust temp would expand the valve and cause it to stick or low lubrication to the valve, someone else posted about the samething, but an alum. head. They said; something about the engine leaning out, they had more than one guide pull out.
What would have happened if i didn't catch it and I kept running it?
Last edited by cloudmaster_321; 08-16-2009 at 10:13 PM.
#9
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Joined: Dec 2002
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From: Dallas, TX
Assuming the previous water reversion caused the issue, shouldn't a relatively inexpensive guide been replaced when the head was reworked? Not sure what water reversion would have to do with a pressed fit guide. At this point, it will likely be hard to determine who shot who. It seems to me it would be worth asking for some consideration from your engine builder.
#10
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Joined: Jun 2004
Posts: 1,144
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From: Sun Prairie, WI
Assuming the previous water reversion caused the issue, shouldn't a relatively inexpensive guide been replaced when the head was reworked? Not sure what water reversion would have to do with a pressed fit guide. At this point, it will likely be hard to determine who shot who. It seems to me it would be worth asking for some consideration from your engine builder.


