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Oil on plugs after rebuild.

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Old 09-12-2017, 09:40 PM   #121
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Originally Posted by LenWoodruff View Post
I drove 125 miles on a cruise Saturday and it used 1/2 quart of oil. That's a lot to me.
that is alot normally, but alot of machining was done to your block...it honestly may come right out of it after another oil change, or slack back to a quart every 1000 miles...why i dont think its nothing serious is i have faith in the new parts and your builder. Hopefully im right. Looking at that oil soaked plug really makes me wonder though
...but builders are just that, builders, it really does fall on the owner to get that oil clean, even if it takes an engine oil flush. I have even heard some machine shops say you need to leave that stuff in there so the walls and rings will seat properly..
​​​​​scary or what!!! I believe even brand new cars they dont want you changing the oil just for that reason until final breakin completes.
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Old 09-12-2017, 09:56 PM   #122
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that would be the best course of action, hopefully he may know something we dont...the bronze guides could explain the gold i see on the valve stems. If nothing comes from talking to builder, take an oil sample on a clean piece of mirror or glass, just dab the oil dipstick on it...if it looks dirty at all compared to new oil, change it. From the pics i seen of drain plug on the rag it looks pretty dirty...it should be clean as new or real close to it. I would guess if valve assemblies were rebuilt as well then its not the valve seals but likely your oil is still contaminated. All those fine particles are caused from the cross hatch honing in the machining of block...it would also explain the 120psi conpression test. I would think your compression should be a little higher...pushing 140, but if the walls are still breaking in, then it will be lower for sure...i wouldnt give it a second thought, i would change the oil....run it for an hour and compare another oil sample. I bet if you pulled the dipstick and checked and oil sample, you will find small particles of grey dust it oil, which tends to stick to crosshatch and cause oil to get by the rings. The only TRUE way of knowing is to inspect walls with pistons at bottom of stroke...if you see crosshatch pattern then you have nothing to do except keep changing oil, and there is nothing to worry about. Good luck in any case!!


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Thanks for the info. I changed the oil about 250 miles ago. Here is what the oil from the dipstick looks like on a piece of glass.

I think it looks like new.






Last edited by LenWoodruff; 09-12-2017 at 09:57 PM.
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Old 09-13-2017, 11:22 AM   #123
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I agree you have done enough due diligence. 120 psi compression, high oil consumption, iron splinters on the drain plug and caked oil on the back of the valves is not normal for a new engine. Hold your engine builder to fixing it before it's too late.

Last edited by Neil B; 09-13-2017 at 11:33 AM.
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Old 09-13-2017, 11:37 AM   #124
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I agree you have done enough due diligence. 120 psi compression, high oil consumption, iron splinters on the drain plug and caked oil on the back of the valves is not normal for a new engine. Hold your engine builder to fixing it before it's too late.
I agree.

I have called and am waiting for him to call me back.
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Old 09-13-2017, 11:56 AM   #125
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I agree.

I have called and am waiting for him to call me back.
When you talk to him, be sure to suggest a leakdown test to confirm the rings are doing their job. If the rings are good, then it's pretty much the heads that are the problem.....which you likely already know.

Your builder needs to stand behind his work.
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Old 09-13-2017, 12:10 PM   #126
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When you talk to him, be sure to suggest a leakdown test to confirm the rings are doing their job. If the rings are good, then it's pretty much the heads that are the problem.....which you likely already know.

Your builder needs to stand behind his work.
Thanks I will make sure I ask for that.
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Old 09-13-2017, 10:49 PM   #127
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Thanks for the info. I changed the oil about 250 miles ago. Here is what the oil from the dipstick looks like on a piece of glass.

I think it looks like new.





It does look good....no grey....thats a good thing....but who set the timing?? I know it sounds like a weird question but is it set correct?? That previous pic a while back of the plug gummed up is scary i know, but is it possible the timing is set way advanced?? I habe seen motors use oil like crazy when timing was out of wack.....to advanced, rattles like a mudda when jerking the throttle, too retarded heats up quick, lots of smoke and odor on a throttle jerk from idling....i cant help wonder if its something simple like timing is off because balancer has moved, or it hasnt been set to spec, if off more that a few degrees could make motor use a little oil, that compounded with initial break in?.?.? Just food for thought.

Two or three quarts for the first thousand miles i dont think is that much...consumption should tapper off exponentially though. What i also think is strange and leaving questions in my head is how black the ports look inside the engines heads....if all the guides were done and vavle job it should be pretty clean, but bad timing would explain that....

Last edited by san; 09-13-2017 at 11:07 PM.
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Old 09-14-2017, 08:45 AM   #128
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Valve timing would explain oil on the intake valves?
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Old 09-14-2017, 10:10 AM   #129
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No i dont mean valve timing, i mean the ignition timing. Who set it?

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Old 09-15-2017, 08:00 AM   #130
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No i dont mean valve timing, i mean the ignition timing. Who set it?
The builder set it when they finished the engine. We checked it a couple of weeks ago and it looked ok.
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Old 09-15-2017, 08:02 AM   #131
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I will be taking the car in Monday to the engine builder. He thinks it is likely the valve seals. I took the bore scope to a couple of the springs I could see from the oil filler hole and I could see umbrella seals there.

So we will see next week whats up I hope.
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Old 09-16-2017, 10:13 AM   #132
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I will be taking the car in Monday to the engine builder. He thinks it is likely the valve seals. I took the bore scope to a couple of the springs I could see from the oil filler hole and I could see umbrella seals there.

So we will see next week whats up I hope.
https://www.carid.com/images/manley/...ts/24046-8.jpg

Umbrella valve stem seals will not do anything. After the valve guides are machined correct, and the valve job is correct, and the valve stem has the correct finish, the valve guides have to be machined for a seal that seals to the valve guide (link above) like these.

Heads that are machined correct even with no valve stem seals will not make the spark plugs look like yours, its time to face the facts, you need to find a shop that takes great pride in there valve jobs and get your heads to them.

Get your bore scope out, pull the passenger side exhaust manifold off, turn the engine over until the number 6 exhaust valve is open, get that bore scope down there in the exhaust port and take a look at the exhaust valve where it seals on the valve seat.....your not going to like what you see.

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Old 09-16-2017, 11:52 AM   #133
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https://www.carid.com/images/manley/...ts/24046-8.jpg

Umbrella valve stem seals will not do anything. After the valve guides are machined correct, and the valve job is correct, and the valve stem has the correct finish, the valve guides have to be machined for a seal that seals to the valve guide (link above) like these.

Heads that are machined correct even with no valve stem seals will not make the spark plugs look like yours, its time to face the facts, you need to find a shop that takes great pride in there valve jobs and get your heads to them.

Get your bore scope out, pull the passenger side exhaust manifold off, turn the engine over until the number 6 exhaust valve is open, get that bore scope down there in the exhaust port and take a look at the exhaust valve where it seals on the valve seat.....your not going to like what you see.
I agree that those are the best valve seals to have. I just worry that since you have to cut the head to fit them that would make it prone to cracking down the road.

What would you expect I would see with the exhaust valve open with the bore scope? Oil leakage?
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Old 09-16-2017, 03:52 PM   #134
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Originally Posted by Vortecpro View Post
https://www.carid.com/images/manley/...ts/24046-8.jpg

Umbrella valve stem seals will not do anything. After the valve guides are machined correct, and the valve job is correct, and the valve stem has the correct finish, the valve guides have to be machined for a seal that seals to the valve guide (link above) like these.

Heads that are machined correct even with no valve stem seals will not make the spark plugs look like yours, its time to face the facts, you need to find a shop that takes great pride in there valve jobs and get your heads to them.

Get your bore scope out, pull the passenger side exhaust manifold off, turn the engine over until the number 6 exhaust valve is open, get that bore scope down there in the exhaust port and take a look at the exhaust valve where it seals on the valve seat.....your not going to like what you see.
the intake port and intake valve guide are under engine vacuum so oil will get sucked into the guide. the exhaust ports and guides are under positive pressure so the oil will not get sucked into the exhaust port. I build all my high performance engines from 1964 till 1994 when I retired with positive seal on the intakes and umbrella seals on the exhaust and never had a problem with oil burning.

Last edited by PAmotorman; 09-16-2017 at 03:54 PM.
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Old 09-16-2017, 06:18 PM   #135
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[QUOTE=LenWoodruff;1595580568]I agree that those are the best valve seals to have. I just worry that since you have to cut the head to fit them that would make it prone to cracking down the road.

What would you expect I would see with the exhaust valve open with the bore scope? Oil leakage?[/QUOT

Your going to see a burnt blackened valve at its sealing point. No valve guide design in the world is going to work if the guides are not done right, along with the valve job. I can assure you valve guides do not crack from being machined for a positive seal.

How cylinder head work is done:

sehttp://www.chevelles.com/forums/13-performance/948193-bbc-closed-chamber-head-restoration-pictures.htmlal.

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Old 09-16-2017, 06:54 PM   #136
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[QUOTE=Vortecpro;1595582534]
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Originally Posted by LenWoodruff View Post
I agree that those are the best valve seals to have. I just worry that since you have to cut the head to fit them that would make it prone to cracking down the road.

What would you expect I would see with the exhaust valve open with the bore scope? Oil leakage?[/QUOT

Your going to see a burnt blackened valve at its sealing point. No valve guide design in the world is going to work if the guides are not done right, along with the valve job. I can assure you valve guides do not crack from being machined for a positive seal.

How cylinder head work is done:

sehttp://www.chevelles.com/forums/13-performance/948193-bbc-closed-chamber-head-restoration-pictures.htmlal.
Thanks for the link. I see where the valve guides were cut for the positive seal.

If there is nothing wrong with the seals then the problem has to be the guides weren't done correctly and the only solution would be the positive seals?
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Old 09-19-2017, 08:23 AM   #137
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I pulled my 3 and 7 plugs last night to look at them again, they were cleaned about 400 miles ago. They have a lot of thick, black oil on the threads and towards the seal but the tip looks dry with some carbon build up. There is no oil on the outside of the plug hole. So is the oil getting into the cylinder and being burned off the tip of the plug and collecting in the threads? Sorry to piggy-back this thread but my problems sound very similar.
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Last edited by See Three; 09-19-2017 at 08:24 AM. Reason: Added apology
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Old 09-19-2017, 08:40 AM   #138
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I pulled my 3 and 7 plugs last night to look at them again, they were cleaned about 400 miles ago. They have a lot of thick, black oil on the threads and towards the seal but the tip looks dry with some carbon build up. There is no oil on the outside of the plug hole. So is the oil getting into the cylinder and being burned off the tip of the plug and collecting in the threads? Sorry to piggy-back this thread but my problems sound very similar.
What is your oil level doing? Mine is using a quart every 300 miles.

Also my plug have the oil on the intake side of the plug and oil residue on the top of the intake valves.
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Old 09-19-2017, 09:00 AM   #139
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What is your oil level doing? Mine is using a quart every 300 miles.

Also my plug have the oil on the intake side of the plug and oil residue on the top of the intake valves.
Mine was using a quart every 250 miles for the first 1000 miles after rebuild. I'm at 1500 miles now and I think it may be starting to taper a bit but I'll need to put a few more miles on to be sure.
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Old 09-19-2017, 09:46 AM   #140
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Mine was using a quart every 250 miles for the first 1000 miles after rebuild. I'm at 1500 miles now and I think it may be starting to taper a bit but I'll need to put a few more miles on to be sure.
I am at 1700+ miles and it still burning a quart every 3 00 miles. I think the difference for your is there is no oil on the electrode just around the the threads. That is probably oil getting past the rings until they are fully seated.
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