Head Gaskets. Should they be a service item?

[RustyNuts]

I think its probably fair to say most of us have had HGF at some point in our motoring lives and this has got me thinking..

 

HGF seems to happen on older cars mainly from what i can work out.. or some newer cars that have been utterly thrashed.

 

So inside those cylinders are thousands of explosions putting pressure on the gasket and over time they must be wearing down to the point where they fail (this excludes overheated engines where the head warps).

 

So with my (perhaps incorrect) logic, does this mean that a HG should be replaced as a service item?

 

Also as HGF tends to also lead to overheating and a warped head if it hasn't already happened to cause the HGF then presumably replacing the HG as a service job would minimise the risk of a head warp?

 

What are your views on this?

[Bobthebeard]

Yes, it would, but no in reality. Head gaskets are not a service item. Some go for ever, some fail. Like any part of any car really...

[Dirk Diggler]

I've only ever had one fail on something that I hadn't maintained the cooling system, in cars that had marginal enough cooling systems to begin with.

 

Pajero 2.8, Peugeot 405 1.6, BMW 316 and 1.0 Arosa; and each one was more to do with me than anything else

[Lacquer Peel]

Monobloc engines are the future*.

[steveo3002]

hard enough getting folk to change the oil once a year , forget em paying for a headgasket

 

nothing stopping you whipping the head off a well used older car for a freshen up , cleaning the valves and re seating them etc will help it run better , and new stem seals help oil use

[Dave_Q]

No, only a mental would replace a HG "just in case".

 

HGF is normally caused by a lack of maintenance, by the time the chod gets into our hands it's generally spent several years being run on plain water etc, corrosion and so on and the inevitable happens.

[sierraman]

Some engines are prone to them going I.e K Series, XUD etc. Others rarely go, it shouldn't need replacing unless it's suffered a failure, all being well on a modern car you shouldn't have any need to strip down an engine these days if it's looked after.

[richardthestag]

in my earlier years I might have removed a head to decoke it. new head gasket would be fitted along with the "running in" sticker in the back window.

 

Dad used to replace the main bearings in his 1340cc ford Classic engine like they were an annual service item

 

Times change

[Cavcraft]

I'd be one of those 'fix it if goes wrong' types, I think.

[danthecapriman]

I've only ever had old cars, but I've never suffered a HGF. I don't drive my cars hard and I look after them well which probably helps.

The only times I've replaced the head gaskets on my cars it was for other reasons. On the Capri it was to get the head modified for unleaded valve inserts. On the Mercury the head gaskets were the originals, never been changed since 1973. It was only changed because the rest of the engine was worn out and had to be rebuilt.

 

I think your best off leaving it alone until you need to mess with it personally.

[wuvvum]

Dad used to replace the main bearings in his 1340cc ford Classic engine like they were an annual service item

Didn't those engines only have 3 main bearings or something?  I'm sure there was something odd about them.  My Classic had had a 1500 from a later model fitted.

[mk2_craig]

I had a 20 year old Sierra with the twin cam 2 litre lump a few years ago, less than 50k on the clock and mega service history but a coolant weep from the front of the block. I asked a local garage to do the HG just in case - they reckoned it wouldnt be a problem if left untouched and to be fair it gave no bother in my ownership. Though admittedly I only did about 1500 miles in it.

[dollywobbler]

Didn't those engines only have 3 main bearings or something?  I'm sure there was something odd about them.  My Classic had had a 1500 from a later model fitted.

 

845cc Renault engines were only ever 3 bearing...

 

Back to OMG HGF, dangerous to say it, but I've never had one pop. Mind you, the only cars I've ever changed a clutch on are my first car (which proved pointless as it died a death months later) and my current 2CV (twice - 2000 and 2016, though on a different engine). So no, not a service item. Change the coolant, certainly, as few people do. 

[danthecapriman]

Didn't those engines only have 3 main bearings or something?  I'm sure there was something odd about them.  My Classic had had a 1500 from a later model fitted.

Yes, the early 1300 engines were only 3 bearing. The later 1500 was a stronger longer lasting 5 bearing.

[hpi_matrix]

No

[RustyNuts]

No, only a mental would replace a HG "just in case".

 

HGF is normally caused by a lack of maintenance, by the time the chod gets into our hands it's generally spent several years being run on plain water etc, corrosion and so on and the inevitable happens.

 

I used to think that.. but then the trouble is that if it does go and you're not aware of it then the head may be warped badly and then you're buggered twice.

[sierraman]

Why not swap the engine while you are at it.

[J4mes]

In my experience HGF isn't an instant thing, theres usually reasons/symptoms that lead up to it.

I knew the Alfa's HG was failing for about 6 months before it went properly and used all its coolant in a oner. I'd never change one as a service item, just when it eventually failed or pissed me off having to top up fluids..

[fordperv]

I had a 20 year old Sierra with the twin cam 2 litre lump a few years ago, less than 50k on the clock and mega service history but a coolant weep from the front of the block. I asked a local garage to do the HG just in case - they reckoned it wouldnt be a problem if left untouched and to be fair it gave no bother in my ownership. Though admittedly I only did about 1500 miles in it.

I'm a just in case person as well when I put the replacement engine i my saph i changed to the multi layer steel gasket just in case, i was right to as well the gasket had signs of going from no4 cylinder to water jacket

[Parky]

Aren't some recent BMW engines basically scrap if you remove the head?

 

Something to do with the metal in the block or something. If indeed true, I wouldn't recommend a preventative HG change ever!

[Pillock]

If the cambelt snaps, it's a scrap engine. Hence service item. If the oil becomes less oily, the engine is also badly damaged. Hence service item.

 

If the head gasket goes, under most circumstances it'll just need a new gasket. Even if it's driven too far, it's a skin and gasket. Why change it until you need to?

[Matt]

Monobloc

 

Turns out not even Google can wrap it's enormous electronic brain around this idea and has spun into an endless 'Did you mean' loop.

 

[sierraman]

If it's a really big worry for you around headgaskets I'd suggest getting a Leyland National with the original 510 engine in.

[lisbon_road]

I'm not in a rush to change head gaskets for fun, but I think there is a case for it.  Bear with me.........

 

The argument is this.  When the head is cast, the casting isn't that stable and it tend to move.  Years ago, before just in time manufacture, some companies would purchase castings and age them so that they distorted less.  Others would take two cuts - so machine a face, then store the casting and cut it again.  No-one has done this sort of stuff for an age, but I remember Avery Hardoll, who made petrol pump meters, would get the castings and store them for a year or so.  Before my time mind.

 

The argument therefore goes that the cylinder head moves after it has been first fitted, and should be much more stable after the first skim.  Thus if it is removed and skimmed at (say) a few years old and perhaps 50K miles, it won't have to be done again.

 

I read vaguely that more modern cars can't tolerate skimming and so on, but just thought I'd throw in my own thoughts.

[tommytwo]

I did the HG on my Rover 820 last May, by which time it had been in service for 24 years and 144k miles. Not because it was failing or losing water, but to fix the engine oil leak  that the T series engine is famous for. The oil leak was right on the corner of the block by the dizzy.  Popped a piece of copper tube in there with some RTV sealant on the gasket and it has not leaked since.

 

Monobloc engines may well be the future but casting technology and materials science is advancing all the time so I think we will see plenty of cars yet to come with separate cylinder heads. There are bound to be some problems show up with monobloc engines that  very wise men have overlooked. IMHO.

[Dave_Q]

I used to think that.. but then the trouble is that if it does go and you're not aware of it then the head may be warped badly and then you're buggered twice.

 

Gasket failure on it's own doesn't warp or crack heads, overheating does. Something has to be significantly cooked to do serious damage to a big lump of metal.

 

I would still prefer to keep an eye on the temperature gauge and turn the car off and investigate if it's overheating rather than change the headgasket for fun.