...this is not good :(
...this is not good :( Reference:
https://ls1tech.com/threads/showflat...31&fpart=1
In the above post I said I was worried, and it looks like I was right. Today I finally got a code and a flashing SES, I pulled the codes, misfire on cylinder 7, ok, no biggie, right? wrong. I pull the plug and to my horror it is covered in oil and carbon deposits.
Ok, so now I have a problem, is it a bad ring? or a valve seal? Is a valve stuck open? Goto murrays, grab a compression tester for $30... cylinder #7 - 15psi, cylinder #5, 180psi, sanity check, cylinder #7 - 15psi
This is not good. What can cause no compression? A blown head gasket? valve stuck open? blown ring?
here is what happened, on my way to work in the morning the car started to studder at low rpm's, the previous day I had not raced it or put stress on it, so to me, a ring problem seems highly unlikely, anyone have any ideas?
thanks
-Steve
https://ls1tech.com/threads/showflat...31&fpart=1
In the above post I said I was worried, and it looks like I was right. Today I finally got a code and a flashing SES, I pulled the codes, misfire on cylinder 7, ok, no biggie, right? wrong. I pull the plug and to my horror it is covered in oil and carbon deposits.
Ok, so now I have a problem, is it a bad ring? or a valve seal? Is a valve stuck open? Goto murrays, grab a compression tester for $30... cylinder #7 - 15psi, cylinder #5, 180psi, sanity check, cylinder #7 - 15psi
This is not good. What can cause no compression? A blown head gasket? valve stuck open? blown ring?
here is what happened, on my way to work in the morning the car started to studder at low rpm's, the previous day I had not raced it or put stress on it, so to me, a ring problem seems highly unlikely, anyone have any ideas?
thanks
-Steve Re: ...this is not good :( nope, not yet. I praying that nothing smacked into the pistion, I really do not feel like having to get that fixed 
If a spring broke, would that cause all of these problems? Also, wouldn't it hit the piston?
thanks
-Steve
If a spring broke, would that cause all of these problems? Also, wouldn't it hit the piston?
thanks
-Steve
Re: ...this is not good :( If you are running dual springs, you shouldn't have made contact with a piston. The inner spring will hold the valve up and not let it hit. When you installed your cam and heads.. did you do hardened pushrods? If you didn't install them, the stock ones will bend VERY easily.
Re: ...this is not good :( Tin Indian - The heads are unmilled.
Gomer - Yes, running 978's that were pre-installed by terry. I installed Manley hardened pushrods when I did the H/C swap.
If a spring broke after 3k miles...thats not a good thing...
-Steve
Gomer - Yes, running 978's that were pre-installed by terry. I installed Manley hardened pushrods when I did the H/C swap.
If a spring broke after 3k miles...thats not a good thing...
-Steve
Re: ...this is not good :( I've been running those springs for a while without a problem and I haven't heard of any failures with them yet.. BUT, that would be one of the easiest things to check. Keep us posted.
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Re: ...this is not good :( Do a leak down test to determine the problem, if you hear hissing in the exhaust or intake then it's a valve problem, if you hear hissing in the oil intake its a ring or a hole in the piston, if you see air bubbles in the coolant, you've got a blown head gasket.
Re: ...this is not good :( How do I do a leak down test? How can I distinguish between the sounds? Is it really noticeable?
I live in Troy, MI, I have quite a few shops to help me, I wanted to avoid them at all costs..
-Steve
I live in Troy, MI, I have quite a few shops to help me, I wanted to avoid them at all costs..
-Steve
Re: ...this is not good :( Dragon - I didn't check, should I just take the filler cap off and look? The cylinder #7 is on the drivers side.
What should I look for on the dipstick at idle? Smoke? I really don't think I see any on the drivers side.
-Steve
What should I look for on the dipstick at idle? Smoke? I really don't think I see any on the drivers side.
-Steve
Re: ...this is not good :( You need a leak down guage and air. With the piston at absolute TDC...with guage /supply air off, install air line from leak down guage into the spark plug hole of cylinder to be checked...supply air on to that cylinder...supply guage will show psi of air going into the hole...2nd guage will show amount of leak down in percentage. I use 100 psi supply air just b/c it's easier to figure leakdown percentage.
Not a hard job...just takes a little time. You can do this yourself, and for the $ spent to have a shop do it, you can purchase the guages and add to your tool collection
I agree w/the above posts....check the springs/pushrods 1st...then if all is well...do a compression/leakdown. Good luck
Not a hard job...just takes a little time. You can do this yourself, and for the $ spent to have a shop do it, you can purchase the guages and add to your tool collection
I agree w/the above posts....check the springs/pushrods 1st...then if all is well...do a compression/leakdown. Good luck
Re: ...this is not good :( For the compression test, does it need to be at WOT?
I don't have access to air tools right now, I'm gunna get a quote and see how much it'll run me.
thanks again
-Steve
I don't have access to air tools right now, I'm gunna get a quote and see how much it'll run me.
thanks again
-Steve
Re: ...this is not good :( I called a local shop and they said they don't usually do leak-downs and that they can hook up a vacuum gauge to it to see if a valve is bad. What do you guys think? He said they would do a leakdown but it will cost a lot more and that the vacuum test would be cheaper and still show what is wrong with the car.
thanks
-Steve
thanks
-Steve