So I noticed idle little rougher, low compression in #3, and burning oil so I assumed the worst: broken ring lands in my stock b18b block...

I tore it down all the way and pulled the piston, to my suprise it was fine, so i put it back together NO BROKE RINGLANDS

my question is if something in the head (bad valve seals?) could this cause what i'm seeing?

compression results: (today, sometimes it's normal!)

165 100 170 170

When i start it up after sitting for about 10min (still warm) it idles rough for about 2 min... as if oil was leaking in to #3 while it was sitting.

Also i can see that #3 is wet with oil, spark plugs conferm (#3 is much darker)

So is it my valve seals or what? bent valve?

This is on my LSVTEC turbo

 

bump

 

do a leak down, it will help to pinpoint the problem. I am in the Sacramento area and am a mechanic. Hit me up if you need help, I might be able to lend you a hand in figuring it out.

 

i don't own a leak down tester... or an air compressor for that matter.

 

i would agree with your diagnosis of the valve seals. It prolly leakin past them into the intake charge. I would also guess blown HG but seeing as how u tore it down and put it back together i doubt its that.

valve seals on #3 ftw

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbotime &raquo;</TD></TR><TR><TD CLASS="quote">i would agree with your diagnosis of the valve seals. It prolly leakin past them into the intake charge. I would also guess blown HG but seeing as how u tore it down and put it back together i doubt its that.

valve seals on #3 ftw</TD></TR></TABLE>

Except for valve stem seals would not cause a drop in compression. So out the door goes that theroy. Blown headgasket you would MOST LIKELY (not always) see in low compression results side by side... so if 3 is low, suspect 2 or 4 to be low also... not always, but its a possability. He says it doesn't smoke though, so I would highly doubt thats the issue. I am in contact with him on IM, he might come by tonight. I'll know whats wrong then.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid93Eg &raquo;</TD></TR><TR><TD CLASS="quote">He says it doesn't smoke</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sketch_hs &raquo;</TD></TR><TR><TD CLASS="quote">

Also i can see that #3 is wet with oil, spark plugs conferm (#3 is much darker) </TD></TR></TABLE>

so the piston #3 spark plug is covered in oil- yet it doesnt smoke?

only other explanation for (the low compression) is a bent valve on #3, or possibly warped cylinder chamber

 

so i did the oil in cyl test and found that compression jumped like 40psi in #3

guess rings are shot! I don't know why

this test shows bad rings 100% correct?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbotime &raquo;</TD></TR><TR><TD CLASS="quote">

so the piston #3 spark plug is covered in oil- yet it doesnt smoke?

only other explanation for (the low compression) is a bent valve on #3, or possibly warped cylinder chamber</TD></TR></TABLE>

No. Read what he wrote as a follow up. Remember, he took things apart and INSPECTED them, but he never replaced anything. You can have small amounts of oil in the chamber and never see smoke as most of it will be devoured in the cat.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid93Eg &raquo;</TD></TR><TR><TD CLASS="quote">No. Read what he wrote as a follow up. Remember, he took things apart and INSPECTED them, but he never replaced anything. You can have small amounts of oil in the chamber and never see smoke as most of it will be devoured in the cat. </TD></TR></TABLE>

ok why were his plugs on #3 covered in oil then exactly? I understand he disassembled, and reassembled without replacing anything. SO his plugs were oily before he took it apart and after right? so what exactly are you saying? The problem exists before and after reassembly i understand that.

I woul dhave guessed the rings from the start but he stated he took it apart and the rings were fine so i assumed he knew what he was talking about.

I think my alternatives to the rings are perfectly reasonable and im not really sure what your trying to get at? You just like saying im wrong to everything without chancing any guesses of your own? Sorry my eDiagnosis isnt spot on, im only doing this based on the information he has provided.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid93Eg &raquo;</TD></TR><TR><TD CLASS="quote">No. Read what he wrote as a follow up. Remember, he took things apart and INSPECTED them, but he never replaced anything. You can have small amounts of oil in the chamber and never see smoke as most of it will be devoured in the cat. </TD></TR></TABLE>

no cat


did you guys read my last post?

does anyone know if that makes it 100% rings?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbotime &raquo;</TD></TR><TR><TD CLASS="quote">

ok why were his plugs on #3 covered in oil then exactly? I understand he disassembled, and reassembled without replacing anything. SO his plugs were oily before he took it apart and after right? so what exactly are you saying? The problem exists before and after reassembly i understand that. </TD></TR></TABLE>

First, there is only one plug. This isnt a 2.3l ford ranger here. So if you understand then why cant you grasp that the oil is coming past the rings and thus you have the explanation for oil on the plug..

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbotime &raquo;</TD></TR><TR><TD CLASS="quote">
I woul dhave guessed the rings from the start but he stated he took it apart and the rings were fine so i assumed he knew what he was talking about.
</TD></TR></TABLE>

Mistake number one. How many people here do you really think would know how to inspect a ring and tell if it was worn or not?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbotime &raquo;</TD></TR><TR><TD CLASS="quote">
I think my alternatives to the rings are perfectly reasonable and im not really sure what your trying to get at? You just like saying im wrong to everything without chancing any guesses of your own? Sorry my eDiagnosis isnt spot on, im only doing this based on the information he has provided.</TD></TR></TABLE>

Its reasonable to think failed valve guide seals would cause a drop in compression? Its not that I WANT to always say you are wrong, but comments like that leave you wide open for correction.

The information provided has nothing to do with making wild guesses... If someone has a rough idle issue, do you tell them to check the seat belt tension?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sketch_hs &raquo;</TD></TR><TR><TD CLASS="quote">

no cat


did you guys read my last post?

does anyone know if that makes it 100% rings?</TD></TR></TABLE>

Yes. The oil could not seal a blown headgasket... well, it could if it was a small break, but the would be unlikely with the numbers you have posted. The oil cannot seal a bent valve either, but it can make up the difference of the rings. It would also explain the loss of oil you are experiencing as well.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid93Eg &raquo;</TD></TR><TR><TD CLASS="quote">Yes. The oil could not seal a blown headgasket... well, it could if it was a small break, but the would be unlikely with the numbers you have posted. The oil cannot seal a bent valve either, but it can make up the difference of the rings. It would also explain the loss of oil you are experiencing as well.</TD></TR></TABLE>

thanks hybrid

 

So what could have caused the rings to go out in #3 like this???

washed the rings?

i'm going to have the injectors tested by RC i guess. Maybe #3 is sticking open or something strange...

anything else that could have killed them?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sketch_hs &raquo;</TD></TR><TR><TD CLASS="quote">So what could have caused the rings to go out in #3 like this???

washed the rings?

i'm going to have the injectors tested by RC i guess. Maybe #3 is sticking open or something strange...

anything else that could have killed them?</TD></TR></TABLE>

Poor finish on the cylinder walls, bad rings, lack of lubrication, excessive heat, thats about all I can think of. For the cost of it, just flow the suspected 'bad' injector and see where it sits at. I think its $20 per injector to flow them the last time I checked. You did tell me in PM you drove around for a while on a rich base tune. How rich was the tune? I mean, I killed the rings in my B18C before running horribly rich.. but I am talking about 10:1 rich. It also destroyed the cat as well, which you don't have to worry about I guess.

 

oh wells

time to build the block

 

i know what do do from past experience, if its a valve seal, u will have all the symptoms u are havin now, also a good way to make sure its a valve seal, is after u drive ur car, take off the intake manifold and exhaust manifold, u will usually see oil dripping down from where the valve is if its a valve seal, i noticed it when i took my exhuast manifold on, there was a easy to see stream of oil coming from two of the exhaust valves in two different cylinders, i replaced the valve seals, gave myself a valve adjustment and i'm all good now, hope this helps seeya

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92gsrteg &raquo;</TD></TR><TR><TD CLASS="quote">i know what do do from past experience, if its a valve seal, u will have all the symptoms u are havin now, also a good way to make sure its a valve seal, is after u drive ur car, take off the intake manifold and exhaust manifold, u will usually see oil dripping down from where the valve is if its a valve seal, i noticed it when i took my exhuast manifold on, there was a easy to see stream of oil coming from two of the exhaust valves in two different cylinders, i replaced the valve seals, gave myself a valve adjustment and i'm all good now, hope this helps seeya</TD></TR></TABLE>

I don't think you do know. First off, I wish people could use the proper term. Its a VALVE STEM SEAL, not a valve seal. I think the whole thing with people getting "Valve seal" stuck in thier head is how they magically think a bad STEM seal could cause low compression. A stem seals job is only to LIMIT the amount of oil allowed into the guide. Obviously it is NOT what seals the combustion chamber. That is controlled by the fact of the valve and the valve seat (valvejob) and would only be effected by burnt valves, bent valves, carbon, etc. A failed stem seal would in no way allow compression to drop.