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Internal engine gaskets/ect.?

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#41 ·
did you follow Tang's instructions for warming up the engine and such? Those are way too low, I don't think the car would run with that low PSI...
 
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#42 ·
and best way I have found is oven cleaner and time. Or take it to a machine shop and have them give it a good bath
 
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Discussion starter · #43 ·
xtreme 2 said:
did you follow Tang's instructions for warming up the engine and such? Those are way too low, I don't think the car would run with that low PSI...
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read edit

Also, I guess this is normal... the reads were like puffs of air and not consistent. Like.... pressure, drop, pressure, drop, pressure, drop. Just thought I would mention.

Really don't want to have to put all the plugs back in and run the car just to take them all out again and warm it up Lol.
 
#46 ·
sorry I don't check the forums much after 5pm. Gotta play catch-up every morning LOL.

when you get the puffs, is the 70 psi the max is reached or does it hold steady?
 
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#47 ·
xtreme 2 said:
sorry I don't check the forums much after 5pm. Gotta play catch-up every morning LOL.
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Ditto.


Go ahead and test the other three cylinders just to see if they are all close to each other. 90-100 psi is quite low. How many miles are on this engine?
 
Discussion starter · #48 ·
96k

I am about to the point of looking for another engine. I have a decent amount of extra money coming in soon. I am really considering buying a GT engine and all the extra parts and doing a swap. If I can't find a doner GT or the parts at a good price, then I will just go with another 3.8L.

The readings were consistent 90-100psi and were like puffs of pressure. Not a non-stop reading.
 
#51 ·
yea engine needs to be NOT...
 
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Discussion starter · #52 ·
I re-did the compression test. I ran the engine for 20mins before doing it, so it was hot. I still got 90ish psi on every cly.
 
#53 ·
Zatrekaz said:
The readings were consistent 90-100psi and were like puffs of pressure. Not a non-stop reading.
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It won't be a non-stop reading. You'll lose pressure on every exhaust stroke.

The results from the test definitely point toward less than desirable ring sealing, and would explain the excessive blowby you're experiencing. I'm surprised at the low mileage at which this is occurring though.
 
#54 ·
Zatrekaz said:
I re-did the compression test. I ran the engine for 20mins before doing it, so it was hot. I still got 90ish psi on every cly.
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Re-run the test and put a squirt (about a tablespoon) of oil in each cylinder before you test it, if adding oil raises the numbers significantly then your rings are bad and if the numbers stay about the same then the problem isn't your rings.

Another possibility with low even numbers is a faulty gauge, sometimes the rentals get dropped. I've gotten 195psi on all cylinders when testing my 3.8 cold, and I've tested engines with 35% leak down that still passed compression tests so for your engine to fail a compression test so badly and still run really makes me think the gauge is faulty. Another option is your cam jumping time, it's damn near impossible with a timing chain but still I've seen it happen.
 
#55 ·
^^ didn't think about the gauge being faulty...

though he did say he bought a new one because the rental was incomplete.
 
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Discussion starter · #56 ·
Tang Stang said:
It won't be a non-stop reading. You'll lose pressure on every exhaust stroke.

The results from the test definitely point toward less than desirable ring sealing, and would explain the excessive blowby you're experiencing. I'm surprised at the low mileage at which this is occurring though.
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So, for the ring seals... that is gonna be a massive repair correct?

SALEEN961 said:
Re-run the test and put a squirt (about a tablespoon) of oil in each cylinder before you test it, if adding oil raises the numbers significantly then your rings are bad and if the numbers stay about the same then the problem isn't your rings.

Another possibility with low even numbers is a faulty gauge, sometimes the rentals get dropped. I've gotten 195psi on all cylinders when testing my 3.8 cold, and I've tested engines with 35% leak down that still passed compression tests so for your engine to fail a compression test so badly and still run really makes me think the gauge is faulty. Another option is your cam jumping time, it's damn near impossible with a timing chain but still I've seen it happen.
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So are you saying that the car may have jumped time, or the cam jumped time? What is the difference?

xtreme 2 said:
^^ didn't think about the gauge being faulty...

though he did say he bought a new one because the rental was incomplete.
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Correct... I guess I could go get the rental gauge and attach it to my adapter. Kinda tired of doin the test to be honest however. Just gonna take it to the shop in about a month when I get my student loan reimbursement check.

Was gonna pay off some debt... lol... damn repairs.
 
#58 ·
Yes piston rings require a complete teardown of the block. Lots of labor, parts aren't too expensive though...
 
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Discussion starter · #59 ·
Read this thread :p

This is where I found the issue related to oil on the plugs, and have been discussing causes ect. The V8 thread was me considering a new engine because of the findings in this thread.
 
#60 ·
Zatrekaz said:
read edit

Also, I guess this is normal... the reads were like puffs of air and not consistent. Like.... pressure, drop, pressure, drop, pressure, drop. Just thought I would mention.

Really don't want to have to put all the plugs back in and run the car just to take them all out again and warm it up Lol.
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I don't understand this. Most compression testers have a check valve so that the gauge holds the maximum pressure. I would suggest re doing the compression test with the right kind of tester.
 
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