First drive of my first porsche, not a good start

[dunc]

Finally got to drive my 87 944 turbo and it's not good news

Firstly I think I've bought a car with a goosed head gasket, the coolant levels went mental, pressurised, then low, then high. A look in the oil cap confirmed mayo, strangely it doesn't over heat when driving but all the other clues are there. Anyone want to take a wild guess at the cost of getting the gasket and belts done at an indy specialist?

Secondly it's whistling like a singing kettle on boost! A leak somewhere I'd assume, I did notice the air box isn't in perfect condition so could this be the problem?

This was bought as a non-runner but fixed once I'd bought it by fitting a DME relay, perhaps this was a step too far in terms of bravery. Incidently I have previously done a compression test which was immaculate and also checked the turbo for play.

Thanks in advance for any responses,

Dunc.

 

[Diver944]

This 'might' not be your head gasket. The good signs are it doesn't overheat and the fact that you have mayo is nothing to worry about by itself. All of our cars that have not done many long trips in warm weather will have mayo all over the cap. Get a garage check for signs of oil in the coolant.

Coolant loss could just be a leak somewhere so have a good look underneath when its running. One place to check is the metal bar that runs from front to back above the exhaust manifold. Any leak here comes out as steam and can be difficult to spot.

If you simply replace the head gasket with no other work to the head I would expect an Indy to charge between £600-£1000

The airbox should not be the cause of the whistle, it is in front of the turbocharger so will not be under boost at any point

 

[edh]

how about trying to bleed the cooling system to make sure there is no air in it? there is a bleed screw on the head.

headgaskets can fail without any oil/water mixing. check for hydrocarbons in the expansion tank. (any mot place can do this in a matter of minutes).

the expansion tank has an overflow drain pipe - you could also try routing that into a plastic bottle to see if you collect any coolant being forced out.

mayo in the oil cap is quite normal - well a small amount anyway.

if it is the headgasket - well it's not the end of the world as it's probably pretty old, and a new one will last you for a long time.

the whistle could be anything - might be a noisy turbo?

 

[dunc]

Thanks for the response Paul.

Thanks for ruling out the airbox although it will need investigated, I wondered if it could be sucking air and causing a strange induction noise. The coolant looks like it has a rainbow tint to it and seemed to be pressurising excessively then the coolant level would go down (as in disappear) then come back up again. My gut feeling is that the head gasket is to blame but happy to make sure before jumping to any conclusions.

Cheers,

Dunc.

 

[John Sims]

A replacement head gasket isn't the end of the world and will give you a chance to check the bores as well.

Whistling on boost isn't uncommon. The plumbing to the manifold on a 951 is eclectic to say the least with 100's of opportunities for leaks. I've had a whistle for years (even after a new turbo) I seem to recall Paul Smith even took his dashboard out in the search for an evasive whistle. It doesn't make a lot of difference on mine as the fueling is governed by a MAP sensor (Manifold Absolute Pressure) On more traditional metering you might get some over fueling issues subject to the significance of the leak.

 

[chrishak]

Get the car nice and hot to eliminate any condensation, change the oil and coolant then run it for a while to see if the issues continue. If the car was bought as a non-runner, that suggests it hasn't been run for a while in which case lots of minor issues might cease to be a problem after a bit of use.

If there is work to be done, console yourself with the fact that bought as a non-runner, it would have been cheap and so far it has cost peanuts (DME) to get going (both assumptions on my part, of course).

 

[Mike_Pollock]

Hi pressure on the cooling system can be air still in it, 944s are very awkward to bleed and I would guess the turbos more so!

As has been said mayo on a little used car is not a problem - they all do that sir........

They don't like not being used, so it could be a bit of a tantrum...

A common place for the oil and water to mix on n/a cars is the water cooled oil cooler but not sure of the arrangement on turbos.

Also 20 year old head gaskets probably need changing anyway.

 

[dunc]

Hi edh,

Missed your reply there. Do you know what the test for hydrocarbons in the expansion tank is? Also are there various thicknesses or better versions of HG to get, in my experience heads almost always need a skim, although I haven't overheated it that's not to say the previous owner hasn't. Regarding the turbo it doesn't have excessive play and visually looks OK also.

John,

Cheers hopefully the bores are OK given the compression test results and I'll have a quick look around for anything obvious regarding the boost leak, might have a go at lightly pressurising the air pipe system.

Chris,

Your assumptions are correct it's just I was told it was running perfectly before it failed to start (bought from a friend), think it sat up for about 3 or 4 weeks in total without running. What's the benefit of changing the oil on a car with suspected coolant problems, especially if it's likely it'll have to come out again while stripping the top end?

Mike,

I'll have a look at bleeding the system a bit better at the weekend and try to find out where the oil/water lines go in regards to cooling.

Thanks for all the responses [8D]

Dunc.

 

[edh]

test for hydrocarbons - they just stick their exhaust gas analyser over the open top of the expansion tank - any reading of HC's is going to be pretty conclusive.

 

[dunc]

OK I've got a gas analyser so I'll try that this w/e

Thanks for the help folks, hopefully have a better idea of what's going on soon.

Dunc.

 

[geoff Ives]

I hate to be simplistic but... Try taking the header tank cap off and sniffing the tank. If it smells of combustion you have the answer.

 

[T3rra]

I'm having my hg oil seals and belts done at the mo, where are you based?

I took my car all the way 2 Tom barks ( member ) in Gloucester, 200miles one way trip. At 120000 its still on oringnal head gastic. So I thought I best do it along with stage 2 and toms new ecu. Plus a few extras.

I had started 2 worry the hg was going bad. Had a snifter test done came back clear, was get drops in the coolent level and built up pressure long after shut down. Turns out the head was starting 2 go but only very slightly. Got 2 it b4 it needed skimming.

Its not bad idea 2 do the hg if you got no proof off it been done, get oil seal and belts done as well. My belt and pump where pretty recent.

Guess my point is, if you intend on keeping the car, while it drives you got a wider choice off where and who dose the work.

 

[dunc]

I'll have a sniff Geoff []

I'm up in Scotland, Angus.

Cheers,

Dunc.