Precautionary head gasket changing?

[Sandspider]

Hi all

My car is due to go in in a month or two for belts, waterpump and rocker cover gasket. I was thinking of having the head gasket done at the same time - not because there's anything wrong with it that I know of, but just in case - as far as I know, it's never been changed. I saw it mentioned as something that's worth changing just in case on a couple of threads here, and I also thought it would be cheaper to do the HG while much of the front of the car is dismantled for the other bits and pieces anyway...
However, when I asked my indie about it, he said it would take 3 hours (at £60 per hour :s) labour, plus parts. Well, as I've already been quoted £600 odd for the bits above (6 hours labour), this is another expense I could do without. If I don't have it done, and the head gasket does happen to fail while motoring, will it damage any other part of the car? (I know that oil and coolant will mix, but if I don't drive far after it fails, when oil and coolant passages are washed out and refilled would there be any lasting damage?)

Car is a 1986 Lux and has done about 93,000 miles...

Many thanks,

Giles

Now crossing his fingers and hoping he hasn't jinxed it by mentioning it here! [&:]

 

[Lowtimer]

You need to actually read the thread by Barry Hart here:
http://www.porscheclubgbforum.com/tm.asp?m=594101

One of the common failure modes does not involve oil and coolant mixing, whic hmakes it impossible to spot externally or by looking at the fluids, but does effectively destroy the engine through localised overheating and bore scoring.

I would add that a head gasket is not a "just in case" item, i.e. something that might go on forever or might fail - it WILL rot away and fail, the only question is when.

 

[Suffolk944]

As I posted on the Barry Hart thread - my HG is just in the process of being done as part of some other work. Old one has now come off and apparently it was pretty rotten. Happily all bores are ok so was done in the nick of time relatively speaking. I would advise getting it done now and swallowing the expense of it rather than being faced with a knackered engine...

 

[Pastry]

some 944's (especially turbos) but mainly 944 S2's (and some 968's)

I guess 2.5 N/A's not so much then.

 

[homesea]

Jon what head gasket did you go for? (ie standard or after market, wildfire etc)

 

[Copperman05]

I know the guys in the states are keen on testing there engine oil for water (and various other things to monitor wear, etc), its not something we often do here, but there are labs that offer the service for about £35, called a UOA (Used Oil Analysis).

It would show water leaking internally but not externally, and I expect would not show compression loss which may also be indicative of a blown headgasket. If nothing else a test showing water and/or antifreeze in oil (even in small amounts) would at least provide an early warning indicator to get the HG changed ASAP....

Just a thought...

Edd

 

[robwright]

You can get sniff testers for your coolant that measure the presence of HCs. Many garages use them if they suspect a HG may be suspect but there are no outward signs.

 

[Lowtimer]

Unless I am missing something, none of those tests will react to the type of failure Barry is talking about, though, where the coolant flow is short-circuited, because in that case there is no compression loss and no oil/water mixing.

In general I am a big believer in oil analysis: it is regarded as routine in the world of vintage and high performance aeroplane engines, but I don't htink it can help here unless you get a more 'traditional' head gasket failure.

 

[Lowtimer]

ORIGINAL: Pastry

some 944's (especially turbos) but mainly 944 S2's (and some 968's)

I guess 2.5 N/A's not so much then.

Nearer the end of Barry's analysis, you will see that it's not so much that the 2.5NA avoids the head gasket rot, but that the engine is less prone to bore-scoreing and seizing as a result. The failure still happens but it is easier for the 2.5 NA to survive it, largely because that engine runs cooler in the cylinder area anyway, and particularly because the power levels are a lot lower so there is less waste heat knocking about. It still won't be doing it any good, though.

 

[Lowtimer]

Barry did mine last year as part of a much bigger mechanical overhaul. I am not going for super-high boost levels and had a standard gasket.

 

[Sandspider]

ORIGINAL: Lowtimer

You need to actually read the thread by Barry Hart here:
http://www.porscheclubgbforum.com/tm.asp?m=594101

Yep, I read that thread and that's when I thought about changing it. However, my car is 2.5l and has only done 93000 miles, so I was wondering if I could push the head gasket change to the next belt change. I suppose it's not worth the risk, and I may as well bite the bullet and get it done now...

Cheers all.

 

[Lowtimer]

A wise choice. Mileage is not really the issue. It is calendar time that does for head gaskets. Obviously they can be made to suffer prematurely through tricks like running the engine on plain water instead of proper coolant, or any other issues which have led to overheating and head warpage, or monstrous overboost for Turbos, but barring that sort of thing it is down to the ticking of the clock.

 

[Lowtimer]

The point is surely that a very large number of 944s are not on the roads any more, and the population is going down daily, and that people making a decision not to invest in the continuing maintenance of the cars as they start to need things is a significant factor driving that decline.

Obviously it's a free choice for any owner to not change belts, head gaskets or any other kind of anticipatory maintenance if they see fit, you pays (or not) your money, and you takes your choice...

 

[Suffolk944]

ORIGINAL: Sandspider

ORIGINAL: Lowtimer

You need to actually read the thread by Barry Hart here:
http://www.porscheclubgbforum.com/tm.asp?m=594101

Yep, I read that thread and that's when I thought about changing it. However, my car is 2.5l and has only done 93000 miles, so I was wondering if I could push the head gasket change to the next belt change. I suppose it's not worth the risk, and I may as well bite the bullet and get it done now...

Cheers all.

Mines not a N/A of course but has only done 90,000 itself - suspect its more age related than anything else.

 

[Suffolk944]

ORIGINAL: sc0tty


Sounds like more 944 scaremongering to me. If everything we hear about 944s was true, none would be left on the road ! I would like to know how many 944 owners have suffered HG failure, so at least we could get an idea of the scale of the problem. Anyway, I always thought that brown water in the coolant filler tank was the early signs of HG failure, indicate Oil/water cross contamination. Just sounds like the old yarn about timing belts not lasting more than 4 years etc.... maybe the HG failure is the new cambelt scaremongering.

Yes of course not all belts fail one day after their fourth year anniversary and HGs soldier on for years too but to dismiss advice from those who have huge amounts of experience on the cars as scaremongering seems short sighted to me. As one who professes to have huge regard for their 944 I would have thought following such learned advice as a preventative measure to potential mechanical catastrophe would be a no brainer. [8|]

 

[robwright]

Well said Jon. If I may interject it is like saying why bother with waxoyl as not all 944s are rusty but I do it to make sure it doesn't!!! Actually I am now thinking of doing mine. Not tomorrow but in good time as part of planned maintenance. Actually I am thinking of upgrading and then I can maybe tweak the boost up a bit more. Actually I was quite impressed by the ProMAX full HG wildfire kit they are selling containing all the gaskets needed - good value if you ask me []

 

[pauljmcnulty]

ORIGINAL: sc0tty


Sounds like more 944 scaremongering to me. If everything we hear about 944s was true, none would be left on the road ! I would like to know how many 944 owners have suffered HG failure, so at least we could get an idea of the scale of the problem. Anyway, I always thought that brown water in the coolant filler tank was the early signs of HG failure, indicate Oil/water cross contamination. Just sounds like the old yarn about timing belts not lasting more than 4 years etc.... maybe the HG failure is the new cambelt scaremongering.

Not true. If you want to take over the role of 944 Reg Sec then you can deal with these problems every day! Not being funny, I get at least a dozen calls a week from people who've never heard of problems like expensive clutch labour costs, rusty sills, DME relays, FPRs, or any number of 944 quirks.

If you're reading this, the comment about belts not lasting more than four years is very irresponsible. Engines have been lunchd by belts being left over four years, if it was yours you'd be the first to complain that you weren't warned. It's not an "old yarn", it's a broken engine. [:'(]

Most of the issues with the cars start the same way. Someone asks a question, we think it's a one-off, then we learn it's a problem that has affected all the cars due to either age or mileage. If you want to know how many owners have suffered HG failure, it's a lot. The main reason was increased power causing failure, hence the turbo boys either fitting new gaskets or losing their engines. Now, one of the most respected specialists has suggested HGs are becoming a problem for all the cars. He has knowledge based on all the cars he sees, as do the other specialists I talk to all the time. If you really think you are more knowledgeable then please take over? If not, please just accept that this forum, the Club and the 944 Register are all about learning in advance from other people's experience.

Hopefully you service your car within the guidelines laid down by Porsche. I doubt it, let's face it who changes their brake fluid unless they need to? What we have now is cars outside the original life expectancy, so we need to rethink how we maintain them. If you think that the way I recommend servicing a 944 in 2011 is scaremongering, perhaps you need to step up and take over the role, or form a Club for owners who share your opinions? [8|]

 

[robwright]

Excuse me? Did you want to say something or add anything useful to the thread? I just don't understand your comment. Please help. In English if you please.

 

[JM1962]

Just stripped mine this weekend and the head gasket was rotting away. I must admit, I was doing the head job for other reasons (low compression due to valve seating) and would not have stripped it just to do the head gasket.

Edited to add picture showing how gasket had rotted around number 4 cylinder but also becoming porous just about everywhere else. I know the gasket is at least 19 years old and probably original.

 

[simkin911]

I do wish Hartech had a satellite operation in central Scotland. I'd be very interested in their maintenance plan to care for my s2. It would manage my worries over head gaskets, belts snapping etc... or some other major failure.