What could this be?
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
What could this be?
See that streak.Its run's up from where the exhaust valve goes into the valve guide,Then out the exhaust.Its a clean path through the carbon.Could it be sucking coolant or oil? Or leaking valve seals? My pistons still have carbon on them.My plugs looked normal.
Last edited by DRIVER456; Jan 30, 2007 at 09:35 AM.
Pro
Joined: Jan 2007
Posts: 614
Likes: 24
From: Manteca, CA
How did your oil look? Any overtly high oil usage? Is the car burning coolant?
IMHO burning the oil through the valve seals would leave it dirtier and thicker coating on the exhaust. Do you have a PCV setup or running a breather? Are you spraying this setup? What cam is it (valve events) and springs?
Interesting, I am curious about this too!
IMHO burning the oil through the valve seals would leave it dirtier and thicker coating on the exhaust. Do you have a PCV setup or running a breather? Are you spraying this setup? What cam is it (valve events) and springs?
Interesting, I am curious about this too!
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
You say this streak runs from the intake valve up to the valve guide?
If you can see the intake valve thru the exhaust port then you've got bigger problems than a clean streak.
Seriously, something is probably leaking thru the exhaust valve guide, most likely oil, did you find this while doing other work or were you investigating a problem?
What kind of valve seals do you have and how old are they?
Any smoke while the engine is running?
If you can see the intake valve thru the exhaust port then you've got bigger problems than a clean streak.
Seriously, something is probably leaking thru the exhaust valve guide, most likely oil, did you find this while doing other work or were you investigating a problem?
What kind of valve seals do you have and how old are they?
Any smoke while the engine is running?
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
How did your oil look? Any overtly high oil usage? Is the car burning coolant?
IMHO burning the oil through the valve seals would leave it dirtier and thicker coating on the exhaust. Do you have a PCV setup or running a breather? Are you spraying this setup? What cam is it (valve events) and springs?
Interesting, I am curious about this too!
IMHO burning the oil through the valve seals would leave it dirtier and thicker coating on the exhaust. Do you have a PCV setup or running a breather? Are you spraying this setup? What cam is it (valve events) and springs?
Interesting, I am curious about this too!
I've had this setup for about a year and I never added coolant,Come to think of it it was alway's on the full mark.I had the car on a dyno and no white or blue smoke came out the back, I have a PCV setup and I just added a catch can about a month before I took it off the road.I'm wondering if it was a one time thing that happened or after I added the catch can hmmmm.I had to put a half a qt. of oil once in awhile.I had no problems with the motor,Found this doing other work.No spray.Is it possible for coolant to go between the guide and the head?Now that I think about it,Coolant is the only thing that would leave a clean mark.
Last edited by DRIVER456; Jan 30, 2007 at 10:15 AM.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
I talked to a guy once that insisted that it's possible for aluminum heads to get a 'pinhole' from porting. He said that due to the sand in the casting that you could get a very thin wall at the waterjacket in spots because the sand, or air bubbles, get in the casting near the walls. If that happens you could pop the wall and get a dribble...
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I don't know if this applies, just sharing a possibility.
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I don't know if this applies, just sharing a possibility.
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Small UPDATE so far I found a ripped valve seal on exhaust side.Its hard to see in that picture but its there.I hope thats all it is.I'll take apart the other one's and see.
UPDATE again. Well thats not it,The rip did not go all the way through,Its got to be coolant seeping through.Is there any fix for that ,Maybe put some kind of sealant in the Rad. Or would I have to have the guide pressed out and fixed that way?
UPDATE again. Well thats not it,The rip did not go all the way through,Its got to be coolant seeping through.Is there any fix for that ,Maybe put some kind of sealant in the Rad. Or would I have to have the guide pressed out and fixed that way?
Last edited by DRIVER456; Jan 30, 2007 at 02:25 PM.
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Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
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St. Jude Donor '04
You say your coolant level is always on the full mark yet everyonce in a while you have to add a 1/2 quart of oil ...do you still think it's coolant?
Any liquid passing at a high rate of speed over a sooty piece of metal will clean it, I say throw some new Viton valve seals on and forget it.
Any liquid passing at a high rate of speed over a sooty piece of metal will clean it, I say throw some new Viton valve seals on and forget it.
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
.............Paul
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
You say your coolant level is always on the full mark yet everyonce in a while you have to add a 1/2 quart of oil ...do you still think it's coolant?
Any liquid passing at a high rate of speed over a sooty piece of metal will clean it, I say throw some new Viton valve seals on and forget it.
Any liquid passing at a high rate of speed over a sooty piece of metal will clean it, I say throw some new Viton valve seals on and forget it.
Last edited by DRIVER456; Jan 30, 2007 at 05:29 PM.
Pro
Joined: Feb 2004
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From: barrie ontario
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
You say your coolant level is always on the full mark yet everyonce in a while you have to add a 1/2 quart of oil ...do you still think it's coolant?
Any liquid passing at a high rate of speed over a sooty piece of metal will clean it, I say throw some new Viton valve seals on and forget it.
Any liquid passing at a high rate of speed over a sooty piece of metal will clean it, I say throw some new Viton valve seals on and forget it.
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
I think it is the seals.I looked at it closer and it was clean right where the valve goes into the guide and it was kind of wet with alittle oil.I took the valve out slow and it had a tiny bit of oil on the whole stem.Now where do I get Viton seals.Whats the worse that could happen,I'll check it again after I run it a few times and see if its still there.........Paul