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-   -   Compression and leakdown test needed (https://dorkiphus.net/porsche/showthread.php?t=34648)

Intubator 06-03-2015 12:08 PM

If you can get under the car look for carbon deposits or oil at the following areas at each cylinder. 1) Where the heads meet the cylinders and 2) where the cylinders meet the case. If you have stock heat exchangers be patient, it can be a little tricky to visualize some of this. Either way, a leak or carbon deposits at a sealed junction means a compromise in the sealing for whatever reason. If you find an oil leak or "oil moisture" at a cylinder base and only one then look very carefully at the top end of that cylinder at the head and see if there is carbon or oil around the sealing surfaces, if so it might mean a broken head stud. Hopefully you just have a loose header connection for whatever reason. Any chance you hit a Baltimore pot hole and cracked an exhaust tube or stud?

cmartin 06-03-2015 12:24 PM

A leak bad enough to hear is something. It's not very easy to see the entire exhaust system if you still have heat exchangers but it's worth a shot. Plugging the tailpipe briefly with the engine running should ID a leak pretty quickly. If you think you have a broken head stud pop off the valve covers. Do 1 side at a time, with the car on an angle, and you wont even lose that much oil. A broken stud will either fall out or be easily found.

If you arent looking for specific #'s you can listen for the leak. Position the piston at TDC and fill with air. Remove the ail filter. You'll hear air from the exhaust or airbox, loudest cylinder has the biggest leak.

Len 911 06-03-2015 12:27 PM

Pot Hole ..That's funny. Yeah that why I haven't lowered it yet....
I never got a PPI when I bought the car two years ago. It was like this when I bought it.

Len 911 06-03-2015 12:36 PM

1 Attachment(s)
This is what the top end looked like when I removed the fan,

Intubator 06-03-2015 01:08 PM

Hoe does it look on the under side of those two heads?

Len 911 06-03-2015 02:26 PM

I will check when I get home tonight...What you all think...How bad

Intubator 06-03-2015 03:21 PM

I think you need to pull all of the valve covers and check every head stud nut. My guess is that (only a guess) you have a problem with the dilivar head stud(s) on the exhaust side of those cylinders. If any are broken then those head nuts will be super loose. I would recommend that you do not try turning any nuts that are snug, especially on the lower row as these are very brittle and may break. The top row studs should be steel and can be re-torqued with little risk. Unfortunately, if you find a broken stud you should prepare yourself for an eventual top-end rebuild. As i mentioned I had this issue and continued to drive the car for about a year with no damage to the heads or cylinders. I drove without full throttle input though and would back off if I heard the exhaust leaking between the heads to minimize the risk of damage..

Len 911 06-04-2015 07:28 AM

Looks like there is some oil around the bottom also....I will pull the covers off this weekend. If you still wanted to stop by you are more then welcome too. I would love to talk about cars with you. Let me know

Thanks
Len

onboost 06-04-2015 10:02 AM

Quote:

Originally Posted by Intubator (Post 521290)
I think you need to pull all of the valve covers and check every head stud nut. My guess is that (only a guess) you have a problem with the dilivar head stud(s) on the exhaust side of those cylinders. If any are broken then those head nuts will be super loose. I would recommend that you do not try turning any nuts that are snug, especially on the lower row as these are very brittle and may break. The top row studs should be steel and can be re-torqued with little risk. Unfortunately, if you find a broken stud you should prepare yourself for an eventual top-end rebuild. As i mentioned I had this issue and continued to drive the car for about a year with no damage to the heads or cylinders. I drove without full throttle input though and would back off if I heard the exhaust leaking between the heads to minimize the risk of damage..

Yep, exactly what he said..

This will be your quickest and easiest check.. since you're hearing the leak bouncing off the barriers, check for leaks where your exhaust mates to the head.

ducatithunder 06-04-2015 10:13 AM

Bmore open house this weekend? I might be up in the area clearing out the garage.


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