LastMezger

As some of you are probably aware I put the 964 on sale after only a few months of ownership. I like the car but I'm 31 and we've decided we really want a bigger place and in Toronto the more cash you have on hand the better. I'll probably get one again some day...

There are a few buyers interested and one in particular is very serious. He's done his homework on Rennlist, just as I had, and requested a PPI and a leak-down test by Downtown Fine CArs - our local dealership. No problem I say as it was given the full greenlight just 8 months ago by another dealer when I bought the car.

Plenty of car guys have seen and driven the car and everyone agrees its nearly faultless. Everyone except the dealer that is who turns up massive decrompression of two cylinders and says it will be $10,000 to fix.

I was shocked at the news. So much so I took the car an hour out of town to an independant mech on the advice of a friend at PCNA. This guy would give me the straight goods no matter what. Same result...it needs valve guide work. $7400.

Luckily the buyer is still interested albeit at a substantially lower price.

I still have trouble believing it as the car pulls hard and will easily do 120 mph.

Anyway...that's the story. I'm not overly worked up about it just shocked and a bit disappointed that the dealer didn't come accross this when I was buying the car. In retrospect I don't think I specifically requested a leak-down test last summer but you'd think that as part of the PPI they would recommend it given how common and expensive this is. Not to mention that the problem was hinted at to Downtown Fine Cars and the independant guy just by listening to the idle.

ilko

Damn, that suck! How many miles on the car?

LastMezger

89000 KM. 55600 MILES.

74carreraturbo

what was wrong with the idle that they suggested would cause something like this????

stevepaa

At 55K miles, that is unheard of. Really, really strange.

Bearclaw

Wow, I have about the same miles on a '91. Never got a PPI. Runs fine, pulls like a train. Local acknowledged P-car guru who looked it over and drove it said, "Runs good, sounds good" - but we never put a guage on it. But this has me wondering: what do they hear that sounds like a symptom? And what were the comp./leakdown numbers?

74carreraturbo

yeah, he's got me worrying too haha. I just got my 91 with 84K on the clock and it has a little bit of a lumpy idle but i passed that off as coming from the LWF/clutch setup...

LastMezger

I was surprised given the mileage but Auguste the mechanic wasn't. Said that Canadian gasoline is especially damaging.

There is a slight hiccup at idle...I just thought these things had a lumpy cam.

Pulls the same as perfect compression...I'm told that the problem cures itself as the revs rise so under big throttle or at high-speed there is no loss of compression.

J richard

Unfortunately a leakdown will not tell you the condition of the guides, the cylinders will still hold good compression with the guides in poor shape, it's not until the seat gets bad that it will show up in a leakdown test. Also it won't really affect performance until it gets bad enough that the valve no longer sits in the seat squarely and leaks, or so much oil gets by the guide that you foul plugs, or lastly the valve gets tired of banging around and fails.

A good ear can hear a bad guide as long as it has been properly adjusted, but the way to check is to pull the covers and measure the slop in the guide by pushing the top of the valve laterally. So you have to look for this. The early 64's and many of the 3.2's seem to have this premature guide wear problem, but I would agree it seems a bit early.

The factory gives you the service tollerance for the lateral displacement of the valve, did they measure it with a dial guage and give you the dimension? or did they just push them around and say they are bad. Everything is relative, and in your case it could directly play into how much money your car is worth. I'd ask.

Good luck with it.

LastMezger

thanks for the advice. i'll inquire further.

racerboy

Can't you get a whole rebuild on exchange for motor miester for like 6500 bucks?

LastMezger

you tell me. the number i quoted is $7400 Canadian BTW.

pcarcraig

Premature valve guide wear on these engines isn't unheard of. I have an Excellence magazine from 94 where Bruce Anderson received some questions regarding an over-revved engine. The engine had 16k on it, and when disassembled had excessive exhaust valve guide wear.

Also given is the technique for determining acceptable valve guide wear.

1) lift valve off seat by 10mm
2) measure clearance between valve and valve guide by rocking the valve back and forth between its extremes, and using a dial indicator to measure the play.
3) The maximum acceptable play is 0.80 mm for both intake and exhaust valve.

deoxford

Wow ..My car is in the shop right now for the same thing. Number one was bad. We could hear it .
But with them rebuilding all the heads it is not costing me that much.

But my car was the same pulled very hard with no lost of power.

racerboy

http://www.motormeister.com/suz/911_..._engines_5.htm

This is the link on motor meister. You would obv have to pull the engine and ship, etc. But I'd believe that with an essentially brand new motor your car would be worth alot more