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Old 12-31-2008, 12:18 PM   #21
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Originally Posted by sixshooter View Post
Rafa,
Since it wasn't too long ago that you changed the seals and it appears to only be oil fouling the number 2 spark plug, I would suspect that the seal might not be bad due to age (drying out and shrinking/cracking), but due to being cut during installation or being slightly out of position. The restorer would not help these conditions.

I would check on removal and replacement of just the two seals on the two intake valves on the number two cylinder.

Your compression is within tolerances. So you probably don't have a cracked piston ring.

Be careful boosting in this condition because excess oil in the combustion chamber will cause detonation...

Lunch today at Arco Iris: Bistec salteado, arroz amarillo, yucca, garbanzos, plantanos, cafe Cubano.
Oh ****! I want some of that!

BTW, I found an Air compressor and I'm on my way to doing a leakdown test. I'll report results this afternoon. I'll also try to check the valve seals.

Many thanks and if you eat at Arco Iris; enjoy and ask them whether they have any real cold "Presidente" beer.
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Old 12-31-2008, 03:21 PM   #22
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If you are only loosing 1 quart per 3000. That is ok.
It is probably a valve seal. And like said earlier, if they have been changed resently, I bet they are the problem.

Your compression looks good.

Another thought. I have a open filter on my valve cover, it blows some oil out of it from time to time.

IF YOU DUMP THAT STUFF IN YOUR MOTOR~~~!!!!!!!!!! FOLLOW THE DIRECTIONS TO THE PRECISE TEE!!!!!!!!!!!!!!!

Dump it in the time or miles, which ever comes first, that it specifies. You don't want to gook your motor up.


I BET YOU JUST NEED A NEW VALVE SEAL!
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Old 12-31-2008, 04:50 PM   #23
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So, I went with my tuner's head mechanic to a place where there was an air compressor and...somehow we fucked the leakdown tester! It looks like he didn't set it up properly to start with and then it wouldn't read correctly.

I guess being mechanically challenged has these types of consequences!

FWIW; when we took the spark plugs out, they didn't have any oil.

I've decided to change the oil viscosity and see what happens and take it easy.

I'll begin to buy parts for my future build and enjoy the car for the time being.

I will be using the "engine restore" can but only after I change the current oil.

Many thanks to all and a Happy 2009! (I get the feeling we're all going to need it!)
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Old 03-03-2009, 04:17 PM   #24
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Pics of the culprit:

Last edited by Rafa; 03-18-2009 at 06:58 PM.
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Old 03-03-2009, 04:18 PM   #25
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Pics of the solution:

Last edited by Rafa; 03-18-2009 at 06:58 PM.
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Old 03-03-2009, 04:50 PM   #26
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haha no way. looks ok from the top but DAMN
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Old 03-03-2009, 10:55 PM   #27
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Holy crap Rafa! You broke it right!

It looks like you are fixing it right, too.

P.S. Still no sign of a good '73 Firebird...
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Old 03-04-2009, 05:18 PM   #28
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Holy crap Rafa! You broke it right!

It looks like you are fixing it right, too.

P.S. Still no sign of a good '73 Firebird...
Hey shooter; fwiw, it was only piston #2 that failed. No rod damage whatsoever and my mechanic told me that he would've considered using the bearings on a pinch.

One thing that has me content is the fact that one of the mechanics asked who had tuned the car. When I asked him why, he said all the signs showed a good fuel/air ratio. The engine looks good!

BTW, they already honed the short block and the new parts are going in this weekend.

About the Trans Am; with this project and my son's trip to the States, I have more than I can handle!
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Old 03-06-2009, 01:09 AM   #29
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holy smokes!

1L of oil burnt over 5,000kms.. Depending on what kind of driving you do, and you symptoms would usually have led to the guide/seals, but damn. Thats an exception right there!

I'm surprised the top ring still sealed the cylinder with 175psi though. That thing should have smoked like a bitch.
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Old 03-06-2009, 01:16 AM   #30
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I REALLY like your solution
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Old 03-06-2009, 01:35 AM   #31
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Quote:
Originally Posted by aphongt View Post
holy smokes!

1L of oil burnt over 5,000kms.. Depending on what kind of driving you do, and you symptoms would usually have led to the guide/seals, but damn. Thats an exception right there!

I'm surprised the top ring still sealed the cylinder with 175psi though. That thing should have smoked like a bitch.
The oil control ring keeps oil from getting on the compression rings. If they wear out, more oil gets on the compression rings and it will smoke and burn oil. But the extra oil on the rings seals them up so you'll still have good compression.
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Old 03-06-2009, 02:37 AM   #32
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I'm aware of that. Just shocked, in regards to picture two, the second compression ring, and ring lands look completely obliterated. The 10W50 the OP used definately helped with it to keep up compression.

Anyways, its always fun to see something destroyed


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The oil control ring keeps oil from getting on the compression rings. If they wear out, more oil gets on the compression rings and it will smoke and burn oil. But the extra oil on the rings seals them up so you'll still have good compression.
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Old 03-06-2009, 01:37 PM   #33
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So what is the ultimate cause of the damage to the piston?
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Old 03-06-2009, 06:25 PM   #34
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So what is the ultimate cause of the damage to the piston?
I fucked up Jay. I had the base timing retarded to 5 degrees and was facing some coolant heating issues when I ran the A/C. My mechanic suggested that I should try to advance the base timing to 10 degrees to see if that would fix it. Somehow, I advanced the whole timing map by 10 degrees!

You can see the results of my mistake.
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Old 03-09-2009, 07:00 PM   #35
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Some pics:

Last edited by Rafa; 03-18-2009 at 06:58 PM.
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Old 03-09-2009, 07:24 PM   #36
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OOOOOHHH. I am jealous. I'm losing oil and haven't found it yet. I'm hoping it's not as dramatic as yours. Really like the solution though. Turn up the boost.
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Old 03-09-2009, 07:27 PM   #37
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OOOOOHHH. I am jealous. I'm losing oil and haven't found it yet. I'm hoping it's not as dramatic as yours. Really like the solution though. Turn up the boost.
Gotta wait a couple of months but you can bet I'm going to do just that. I'm also installing an AEM WI kit

We're going to do some additional headwork now.
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Old 03-09-2009, 11:00 PM   #38
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Nice pics Rafa, now that's what I call making lemonade!
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Old 03-10-2009, 12:12 AM   #39
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Nice pics Rafa, now that's what I call making lemonade!

lol; that's a good one. Even I understand it!
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Old 03-10-2009, 12:36 AM   #40
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I like your sig Rafa, I stole it and put it in MY second language.

Also, way to keep your head up, lesson learned!
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