just had a PPI, would like to know what you guys thought

[911eers]

Hello fellow pelicans,

I am new to the Pelican Parts world. I am looking to buy my first 911. I looked at an 82 911SC with 80,000 miles on it. I had a PPI done. The leak down test was as follows:

1- 40% @ 115PSI
2- 9% @150PSI
3- Could not get the Spark Plug out, so they did not test that one, they didn't want to risk any damage.
4- 10% @ 145PSI
5- 5% @ 150PSI
6- 10% @ 150PSI

I am kind of new to this. What do these numbers mean and how big of a deal is the 40% leak down? What would it take to fix it and about how much would it cost?

I appreciate all of your guys inputs

[dad911]

The technician doing the leakdown, especially the 40%, should have been able to tell you where it was leaking from (exhaust/intake or breather) to determine if it was a valve or ring.

The psi numbers dont make sense unless that was the results of an associated compression test. Did they run both?

40% is not good.

[saxen]

Run unless it's cheap

[Peter Zimmermann]

Find a mechanic who can get #3 plug out. Then re-do the leak down test; it might be crud on the valve/valve seat of cyl #1 causing a false high number. Cyl #3 plug must be removed, so tell the seller that without complete numbers you will move on. Is the car fresh out of winter storage? Has it not been used for years? You must post a lot more info in order for us to help you to build a complete picture of the car.

[911eers]

Sorry...the car has been sitting all winter, this was the second time it had been out of the garage. The owner has averaged 1000 miles a year since he has owned it, 7 yrs now.

I will call the mechanic tmw to verify where the leak was coming from.

Could the fact that spark plug #3 not being able to come out affect the numbers?

What other info do you guys need?

Sorry, I am new to this.

[911eers]

why was i chargered for 6 spark plugs when he couldn't get #3 out? not cool

[lateapex911]

Whats the asking $? Where are you located? general condition of the rest of the car? Was the shop a Porsche specialist?
Right away, I can suggest that it's probably not for you.

[TibetanT]

Hello There:

I am no expert, but I would think there should be more information about the condition of the car with a PPI. It is not just about the engine leak down numbers and compression testing. While those numbers are important it is suppose to be a complete package of information.

What is the condition of the interior, the exterior, the brakes, the suspension, etc., etc., etc..

Hope this helps, and Good Luck.

[Jdub]

Okay, totally back down and sit. You are about to buy the best sports car in the world. Do the research and forget the spark plug cost.

This might be a winner. How to know? Have a local Pelican step up to have a look if at all possible?

The information you have is based seemingly on a car that has not been used on a regular basis. That can give "bad" readings. Can the car be driven for some time to free up piston rings and the engine as a whole before you consider re-PPI'ing the car with another 911 expert?

Good luck - the SC is such a great car to own - maybe the "easiest" of the 911s>

[fasterlaster]

The note that Cyl #1 was found cracked is interesting as well. Perhaps nothing, but it could suggest something not quite right with that cyl in general. Another thing of note, is the PPI really isn't much of anything. They did a compression/leakdown test, and that's it? A good PPI should contain more information to allow you to make a somewhat informed decision.

[JJ 911SC]

Originally Posted by saxen

Run unless it's cheap

+1.

Do not let the +/- $400 you spent for the PPI affect your choice. Sometime loosing money upfront is a blessing in disguise.

[mr911er]

Originally Posted by fasterlaster

The note that Cyl #1 was found cracked is interesting as well. Perhaps nothing, but it could suggest something not quite right with that cyl in general. Another thing of note, is the PPI really isn't much of anything. They did a compression/leakdown test, and that's it? A good PPI should contain more information to allow you to make a somewhat informed decision.

+1 - was the service sold as a PPI with just a leakdown test? Lots of other things to consider.

If so, on the evidence it revealed, walk away (or expect to pay for a rebuild).

[Jcslocum]

Those number are making my head hurt. #2,5&6 show the same PSI but different % of leakdown. This test is usually done at 100 PSI input and then the differential is your % of loss.

No, #3 had nothing to do with the numbers from the other cylinders. That plug has to be removed before you buy or the cost of repair has to be deducted from the price. It could mean head removal to repair in the worst case.

Why did you pay for the plugs at all?? The owner has them in his car, not you expense in my opinion.

Good luck and if the price is right, it may be a good buy and with some driving, #1 may come up. Could be carboned up with the 1000 miles a year use.

Just my .002

[Packet82]

Sure, the numbers might be off due to having sat in storage all winter, but there is a possibility of a $10k plus engine rebuild being needed. These cars aren't rare enough to take that kind of risk. Move on and keep looking. You'll find another one without the potential issues.

[wrinkledpants]

Originally Posted by Packet82

Sure, the numbers might be off due to having sat in storage all winter, but there is a possibility of a $10k plus engine rebuild being needed. These cars aren't rare enough to take that kind of risk. Move on and keep looking. You'll find another one without the potential issues.

Agreed. Just like in the aviation world - I'd move on from a car that's been rarely driven. To me, a stuck plug and a cracked one indicate neglected maintenance. A crap PPI is just another indication that I should be moving on.

I would either buy a low mileage pristine car that has been meticulously maintained, or a higher mileage car that has been driven frequently. These motors will last a *long* time *if* they are driven frequently.

You need to be able to check the steering, suspension, brakes, too. A complete suspension rebushing will cost 800 in parts. Brakes could have seized pistons, maybe a window regulator needs replacing, probably some oil leaks. I'm almost positive a fan or two will be bad. On top of all that, you have some sketchy numbers for the compression and leak down. A top end will run ya 5-7k, and a total rebuild in the 10k range. You could easily be looking at over 10K to get this to a good running point.

There are plenty of cars out there to choose from. I've never understood why people dwell on cars like this, unless they are really knowledgeable about them with a plan for a ton of DIY maintenance.

[Peter Zimmermann]

Originally Posted by 911eers

Sorry...the car has been sitting all winter, this was the second time it had been out of the garage. The owner has averaged 1000 miles a year since he has owned it, 7 yrs now.

I will call the mechanic tmw to verify where the leak was coming from.

Could the fact that spark plug #3 not being able to come out affect the numbers?

What other info do you guys need?

That's what I thought, stalagtites and stalagmites on the valves and seats. If the car is really sweet otherwise, this is what you have to do. First, drive the car for 100 miles or so, and try to do it in one or two drives. This will "clean" the valves, and should be done following an oil & filter change.

Then, on a barely warm engine, remove the left, upper, rocker arm cover, and spray a good quality product (PB Blaster, WD-40, etc.) around the base of #3 plug. Break the plug loose with an appropriate tool (you're on your own with this, I can't "feel" what you will feel). If it kinda turns a little, leave it sit and let the penetrant work for about 15 minutes. Then screw the plug back in, and then back out. Do this with patience, it might take you fifteen or twenty tries to get the plug out, but it will come out. If the head is damaged, the engine might have to come out/apart. Re-do the leak down test.

Remember, each cylinder is tested as an individual, and the other numbers will not be affected by #3, but that plug must come out anyway. BTW; there is nothing alarming about the leak down numbers (other than #1) now that I know that the car was in winter storage, and maybe not even driven far enough to get up to operating temperature.

You must try and convince the seller, if the car is a good one, to have that #3 plug removed. Does the seller have a mechanic? If not, who's been caring for the car?

Was the rest of the PPI NOT performed because of the leak down numbers?

[wwest]

Originally Posted by 911eers

Hello fellow pelicans,

I am new to the Pelican Parts world. I am looking to buy my first 911. I looked at an 82 911SC with 80,000 miles on it. I had a PPI done. The leak down test was as follows:

1- 40% @ 115PSI
2- 9% @150PSI
3- Could not get the Spark Plug out, so they did not test that one, they didn't want to risk any damage.
4- 10% @ 145PSI
5- 5% @ 150PSI
6- 10% @ 150PSI

I am kind of new to this. What do these numbers mean and how big of a deal is the 40% leak down? What would it take to fix it and about how much would it cost?

I appreciate all of your guys inputs

Mostly a +1 of Pete's post.

Given the storage duration were I the seller I would not have allowed a compression test absent first driving the car under HARD acceleration numerous times, at least twice starting with a COLD engine.

What was the state of the engine, COLD/HOT, for the testing? Pressure tests are meaningless COLD, plus, plug removal would require extra torque.

Determining the cause of the leakdown simply involves squirting a bit of motor oil into the spark plug opening, crank but no start the engine briefly. If there is now less/noral leakdown the piston rings are at fault.

How much is the owner asking?

Stuck plug is a bit of an enigma. Most shops would have gone ahead and removed the plug. UNLESS the effort required was judged to be REALLY extraordinary.....

Oh, broken plug might well have been the "wrenches" fault. Was is broken beforehand...? No real way to know.

[Peter Zimmermann]

Originally Posted by wwest

Given the storage duration were I the seller I would not have allowed a compression test absent first driving the car under HARD acceleration numerous times, at least twice starting with a COLD engine.

What was the state of the engine, COLD/HOT, for the testing? Pressure tests are meaningless COLD, plus, plug removal would require extra torque.

Determining the cause of the leakdown simply involves squirting a bit of motor oil into the spark plug opening, crank but no start the engine briefly. If there is now less/noral leakdown the piston rings are at fault.

How much is the owner asking?

Stuck plug is a bit of an enigma. Most shops would have gone ahead and removed the plug. UNLESS the effort required was judged to be REALLY extraordinary.....

Oh, broken plug might well have been the "wrenches" fault. Was is broken beforehand...? No real way to know.

Good points. And BTW; that broken plug in cyl #1 could have easily been caused by using a tool/socket that didn't clear the surrounding fins - it's a bit tighter than the other five plugs. Of course, the tech that broke it has to be slightly ham-fisted... Was the seller removing/installing the plugs himself, maybe to oil something during winter storage?