Help - PPI revealed one bad cylinder - airline tickets already booked!

[inthedoghouse]

I just had an out of state PPI done and the car checks out great expect for one concerning thing. Cylinder 1 has 35-38% leak down. Its an 1985 3.2 with 139k on it.

Here are the numbers:
Compression 1-6
177, 190, 193, 185, 188, 190

Leakdown 1-6 (%)
38, 5, 3, 5, 5, 5

The car had even leak down numbers in 2004 and 20k miles ago. Its been driven only about 5k miles in the last 5 years.

Questions
1 - does this mean top end needed for sure for ~$6k or is there anyway it could be carbon fouling from limited use recently?

2 - What are the implications if I drive it like this? How long can this go?

Thanks in advance for the advice. I have airlines tickets booked for Thursday to go buy the car and now I am on the fence.

[wolds]

Could be a lot of things. Even something as simple as carbon blocking a valve from closing or a valve set too tight and not closing. You would need to delve deeper to get an accurate accessment of the problem.

[E Sully]

Tough call. Some Carrera's have a tendency for valve guides wearing early. I had an '86 engine that needed guides at about 75,000, others are still running untouched at close to 200,000. It could just be carbon keeping the valve from closing, but it might be carbon from oil leaking past the valve guide. PPI should have specified where the air was leaking from. If the air is leaking out the intake, exhaust, or rings into the case.
Can you have the owner take the car for a good drive and recheck the cylinder? What do the spark plugs look like? If heavy oil deposits then it might need the guides replaced, which amounts to a top end.

[inthedoghouse]

There is a bit more detail on the report. "Technician can hear air coming from cylinder head area. This is most likely due to a bad cylinder base gasket - engine removal and partial tear down would be required to verify and repair." Does he mean head gasket maybe?

Also, it needed a cap and rotor. The spark plugs gaps were .042 vs. factory .028. Any chance its just carbon build up from sitting and/or not enough spark due to ignition parts needing attention?

[Jonny042]

Can you cancel the ticket? Perhaps not a decision to make in a hurry.

[inthedoghouse]

Ticket is nonrefundable - but I can get a credit to use later. Issue is this is my third out of state PPI this year and its getting expensive I know all 25 year old cars will have some issues but just trying to decide if rebuilding the motor right away is needed and worth it.

[porterdog]

Italian tune up then retest?

[X JBM X]

My $.02 - assume the worst, negotiate cost of sale as per findings. If the cost isn't reduced enough to account for the work, then walk, and save the ticket for later. If the negotiation works in your favor, buy the car, drive it some, and have it retested prior to having the top end rebuilt.

[MikeD]

Broken head stud? That will hiss from the bottom of the head. No head gaskets on a 3.2.

[Chuck.H]

I leakdown my engine every time I have it out of the car (about every year) - readings are typically very low leakage (I'm lucky I don't believe the valve guides have every been changed). However, last time I saw a bad reading on one cylinder I slightly freaked until I smacked the valves with a rubber mallet (had the valve covers off for the adjust) and it immediately held pressure. I think it just got a piece of carbon under a valve, maybe during the spark plug removal...

Just something to consider, since you already have a ticket - go and drive the car (hard) and see how the engine feels - it should be fun, peppy and put a smile on your face. No smile, no purchase.

I got my car back in 1993, before widespread internet and these great forums - no PPI, I just went and visually inspected (did put it on a lift) and drove mine and was SOLD!

HTH,
Chuck.H
'89 TurboLookTarga, 349k original miles

[wolds]

Correct me if I'm wrong, but I don't think that a worn valve guide would influence a leakdown test. The cylinder is at TDC with both valves closed, the valve guide would be out of the equation.

Originally Posted by E Sully

Tough call. Some Carrera's have a tendency for valve guides wearing early. I had an '86 engine that needed guides at about 75,000, others are still running untouched at close to 200,000. It could just be carbon keeping the valve from closing, but it might be carbon from oil leaking past the valve guide. PPI should have specified where the air was leaking from. If the air is leaking out the intake, exhaust, or rings into the case.
Can you have the owner take the car for a good drive and recheck the cylinder? What do the spark plugs look like? If heavy oil deposits then it might need the guides replaced, which amounts to a top end.

[Bob Kontak]

Originally Posted by inthedoghouse

This is most likely due to a bad cylinder base gasket - engine removal and partial tear down would be required to verify and repair." Does he mean head gasket maybe?

An air leak at the base (where meeting the case) of the cylinder is a secondary issue regarding leak-down. He must be talking about the top side of the cylinder where it meets the head but can't be sure. Call them.

[inthedoghouse]

Thank you for all the comments. I also talked to a few experienced mechanics. My plan is to go ahead and fly out to see the car in person and drive it on Friday. I will try to get another reading on cylinder 1 leak down also if possible. My hope is its just carbon, but even if not, then I had planned on a valve job at some point anyway. I really wanted to be able to drive it a year or 2 before dropping the engine.

[PDACPA]

Can you go drive the car and take it to the mechanic who did the PPI and let him show you what he was talking about in his notes? Sounds like you paid the guy, so the least he could do is spend 10-15 minutes to go over them and discuss the area of concern.

Good Luck and let us know how it work out. If you buy it, post pics!

[ClickClickBoom]

A bad leak down on one cylinder, in a car that has been sitting isn't that big a deal. In the airplane world Lycoming says as long as the leak isn't from the valves, fly it 10 hours and recheck. Letting these cars sit is the worst thing you can do to them, drive them often and hard. Had some miracle stories of my own involving Brad Penn, and hard driving. If the car is up to snuff, negotiate with the buyer and enjoy the drive home. Change to Brad Penn drive it hard and retest, up to 3-4 or more, as long as its running good, who cares? Missing and sputtering is another story, budget for a drop and toss a used good head, cylinder and piston/ring combo and call it good.

[E Sully]

I would take the flight and give the car a good test drive. Compression numbers look good, and #1 may come into spec after a good drive. If it doesn't smoke except for a bit at start up and runs nicely through the rpm range you should be able to enjoy driving it for some time before a tear down. The bottom end of these engines are solid. You don't say what you are paying for the car or the condition of the body and suspension, so there is no way to guess if the price is fair.
To respond to wolds, you are correct, worn valve guides won't directly show up in a leak down test. I was saying that oil leaking past a valve guide could cause carbon build up on the valve keeping it from seating. That is why I suggested taking the car for a good drive ( Italian tune up) and rechecking the cylinder to see if the leak down improves. It would be nice to know how much oil the car uses in 1,000 miles, but it seems the current owner does not drive it enough to determine.
Just curious, how much mileage on the clutch. It will also play a part in whether an engine and transmission drop are in the near future.
I purchased a used '86 engine and transmission with a stated but not confirmed mileage around 75,000. Here are the pictures after disassembly. You can see what a valve guide leak looks like. This is one of the reasons I like to see the spark plug condition so you can get an idea of what is going on inside. Dropping the exhaust and taking a look into the exhaust port will also show a lot.
If I were having a PPI done, I would want to include removing the valve covers and checking the cam lobes for wear and pitting, and checking for broken head studs.


If you have the ability to work on the engine yourself can cut down on costs. To give you an idea, I was charged $680.00 labor for installing new valve guides, a multi angle valve job, and having the Nikasil cylinders cleaned and prepped for new rings. If it has the KS Alusil cylinders, things could be different. I did all the work disassembling and assembling the engine itself. Add in 6 new exhaust valves, 12 new valve guides, rings, gasket set, sealants, etc. for another $700. Throw in a couple hundred for the special tools. My engine ran like new when I finished.

[andyt11]

X JBM X has it right. Could work in your favour if you can get the price adjusted.

[inthedoghouse]

Great info thanks - pictures are really helpful. Looks like a lot of carbon on your 75k motor - that normal? I could see how that could flake off possibly.

The car has 5k miles on the clutch, rebuilt tranny, short shifter and new bushings - all done in 2006. So other than this possible engine issue, should be no need to drop the engine.

The suspension checked out in the PPI as solid. Paint is original and in great condition as is the interior. Its a color combo I love. Owner says oil consumption is about none but he does not drvie it all that much - only 5 or 6k since 2006.

I will be driving it tomorrow so we'll see how well it pulls and if I can detect anything.

[Jcslocum]

I'm surprised that the tech didn't listen at the usual places for the air at 35% leak-down. Intake, exhaust and oil fill. How hard is that?? Give you a very good idea of where the root cause is. I know if I had that reading I would be all over the discovery process. My OCD wouldn't allow less....

[X JBM X]

Originally Posted by inthedoghouse

Great info thanks - pictures are really helpful. Looks like a lot of carbon on your 75k motor - that normal? I could see how that could flake off possibly.

The car has 5k miles on the clutch, rebuilt tranny, short shifter and new bushings - all done in 2006. So other than this possible engine issue, should be no need to drop the engine.

The suspension checked out in the PPI as solid. Paint is original and in great condition as is the interior. Its a color combo I love. Owner says oil consumption is about none but he does not drvie it all that much - only 5 or 6k since 2006.

I will be driving it tomorrow so we'll see how well it pulls and if I can detect anything.

Good luck man! Keep us posted on how things go!!