Head gasket failure-3rd in 2½ years

[ndevans]

So, after being trailered home from Exmoor last night, I've whipped the head off. As I suspected, the head gasket has failed, between no 2 & 3 pots, again. This is the 3rd since Sept 2018, the last being Nov last year. This one has managed about 2000 miles, the previous one something similar.

The one that's just gone was a copper faced gasket. One of the other two was also copper, the other a composite, but I can't remember which came first. I'll have to check, but I'm pretty sure all have come from different suppliers.

While it's easy to blame the quality of replacement head gaskets (and I know I'm not the only one to have had multiple head gaskets go), I'm entirely open to the possibility that I am doing something wrong. If I am, I'd like to know what, though.

So, assuming for a moment that it's not a quality issue, what could be causing it?

Could the engine be running too hot? If so, would that cause a head gasket failure?

Could a broken piston ring cause a head gasket failure? (I've no reason to suspect a piston ring failure, but let's not make assumptions).

I believe the head is very slightly warped, as there is a slight weep of oil from the block at no. 1 cylinder, on the exhaust side. This is only very slight, entirely manageable in terms of oil loss, and is nowhere near the site of the failure-but nevertheless, could a warped head cause a gasket failure?

My engine, a 1275, has been bored to +040" - does this mean a standard 1275 head gasket is unsuitable?

Going back to quality head gaskets, when it last went, I bought a Payen composite gasket, part no. AF470. I didn't use it, as when I fitted it to the block, the gasket overlapped the top of the bores. I used the copper one instead, as it didn't overlap.
Since the head is off, I am minded to get it squared off anyway.

Grrrrrrr....

Cheers N

IMG_20210606_175235966_HDR~2.jpg (594.67 KiB) Viewed 6475 times

IMG_20210606_175252347_HDR~2.jpg (1.6 MiB) Viewed 6475 times

[jagnut66]

Hi,
Whilst the quality of some head gaskets, copper or otherwise can be questionable I would get hold of an engineers straight edge (if you don't already have one) and check both your head and block, it may be that one or both do need skimming.
What to you may seem a small insignificant weep could be the cause of all your woes....
It doesn't cost that much to have a head skimmed.
Once it's all true a standard 1275 head gasket should be fine, it was for Abby, my old 1275 Moggy.
As for 'hot running' (and excuse me if these seem silly questions), do you have anti- freeze / summer coolant in your engine?
I ask as I have bought three cars on the trot in recent years, all looking well maintained, that were running on plain tap water, leading me to have to clear the waterways..........
Also do you have an oil cooler fitted?
Best wishes,
Mike.

NB: I have one of these, a worthwhile investment:
https://www.ebay.co.uk/itm/362316396414 ... Swj2Ra9Uj8

[ndevans]

I don't have an oil cooler, and I do have antifreeze in the coolant.
I have done a rough check on the head, with a steel rule, but that's very hit and miss. I am prepared to get the head skimmed first, getting the engine out and stripping it is not something I want to do if I can avoid it.

[James k]

I think my experience is a bit unusual from what I read around here but I've had far more luck with the black gaskets you get from auto parts shops than the copper ones.

[philthehill]

Forget about the composite gasket - this is the gasket I would recommend you use. http://www.minispares.com/product/Class ... o%20search

Check both the cylinder face of the head and the top of the block with a straight edge. Any more than 0.003" difference will require the head and the block to be skimmed.

As regards the oil leak near No: 1 cylinder - a common occurrence. One of the reasons BMC introduced the bolt at the front of the head.

See my post regarding centralizing the head and head gasket on the block using the two centralising studs I made. Centralising the head and gasket on the block relative to the bores is most important especially if the bores are over size.
viewtopic.php?f=4&t=73114&p=665577&hili ... ds#p663273

[paul 300358]

Also, measure the head thickness, it should be about 2.75 inch thick. it would be interesting to know if the head has already been skimmed.

[philthehill]

The standard ex factory head should be 2.75" from top face to combustion chamber face - no more no less. Anything less and the head has already been skimmed.
The limiting factor for skimming the head is the oil transfer passage which runs from the N/S front of the head to the up oil gallery under No: 1 rocker shaft pillar.
There should be at least 0.040" remaining between the bottom of the up oil gallery and the combustion chamber face of the head.

[ndevans]

Forget about the composite gasket - this is the gasket I would recommend you use. http://www.minispares.com/product/Class ... o%20search

That's the one that I put on in Dec 2020, that has just gone. The previous one was also a copper gasket, but from a different supplier, and the first one that went, in Sept 2018, was a dark grey composite, from another different supplier.
In fact, the last time it went, it was between 3 & 4. The first one also went between 2 & 3.

[Sleeper]

I seem to remember the "trick" of laying a short length of fuse wire between the cylinders to help seal the gasket ???

John ;-)

[jagnut66]

I don't have an oil cooler,

Personally I wouldn't run one without an oil cooler if your using it regularly and are doing, or want to do, motorway journeys but it's up to you.
In case you decide to fit one here's a couple of links. It's not a difficult job, however if you do fit one you need to fill the cooler before you finally connect it all up, which can be a bit messy and requires patience.
Best wishes,
Mike.
https://www.ebay.co.uk/itm/253895255992 ... SwLqRgr1-2
https://www.ebay.co.uk/itm/121795376856 ... SwZ2laoVlX

[philthehill]

If the Mini spares gasket has failed then there is something not quite right with the block and head contact faces.
Further investigation and rectification needs to be undertaken.

[ndevans]

I don't have an oil cooler,

Personally I wouldn't run one without an oil cooler if your using it regularly and are doing, or want to do, motorway journeys but it's up to you.
In case you decide to fit one here's a couple of links. It's not a difficult job, however if you do fit one you need to fill the cooler before you finally connect it all up, which can be a bit messy and requires patience.
Best wishes,
Mike.
https://www.ebay.co.uk/itm/253895255992 ... SwLqRgr1-2
https://www.ebay.co.uk/itm/121795376856 ... SwZ2laoVlX

How does this plumb in to the block? I have an ex-Marina block, so the oil filter is a screw on type on the upper rear of the block?

[jagnut66]

You've got me there, as both my 1275's were ex-MG Midget engines, so similar in set up (except cc of course) to the Moggy lump and therefore straightforward to fit a standard kit to.
From what I can tell, with a Marina engine you fit an adapter to where the filter screws into the block and the filter then screws in on top.
Here's a couple of kits I found (below), you may also need a different oil filter to the standard Marina one.
The Midget one has 'J' connectors on both ends, the other straight ended take offs, so you also need to decide which will fit better in your engine bay.
Of course you don't have to buy the kits, you could source the parts individually, that may work out cheaper.
The Midget ran a 10 row oil filter, the MGB a 13 row one.
Some will argue for one some the other.
Again installation doesn't look difficult, I'm just on unfamiliar territory here, once you've fitted one I suspect it'll be like riding a bike.....
Best wishes,
Mike.
https://www.google.com/aclk?sa=l&ai=DCh ... d6BQgBEPAB
https://www.google.com/url?sa=i&url=htt ... AdAAAAABAO

[philthehill]

Only fit an oil cooler if you intend to fit a oil thermostat valve. Cold oil can do as much damage as hot oil.
http://www.minispares.com/product/Class ... o%20search
I was running my Minor fitted with a 1098cc engine up and down the M6 motorway doing nearly a 1000 miles per week with foot flat to the floor most of the time and never had any problems with the oil temp and no oil cooler fitted.

[jagnut66]

Only fit an oil cooler if you intend to fit a oil thermostat valve

I have fitted run an oil cooler before without this, without any noticeable negative effects.
However, that was because I wasn't made aware of them before.
So I have found the below diagram online, to aid the fitting of one.

Oil cooler thermostat fitting.jpeg (64.33 KiB) Viewed 6324 times

Just to clarify Phil, the 'from engine' side is the pipe that comes from the back of the block on a Moggy engine?
Also, I take it that you simply cut the pipes and secure them to the thermostat valve with Jubilee clips?
Or do I need special connectors fitted?
Best wishes,
Mike.

[oliver90owner]

Repeated head gasket failure is usually down to the repairer. Other common causes could be over-heating (driver should know if this occurs), pre-ignition - timing, fuel, high compression ratio, or, again, the driver could be involved....

[philthehill]

This is how the Serk Speed oil thermostat I have and which was removed from a Cooper S fitted with a oil cooler.
(The Serk Speed item is the same as the Mini Spares item. The inlet is stamped inlet).
The oil thermostat is served by the pipe that normally feeds to the oil filter. The block union is replaced by a straight pipe union with rubber oil pipe to the thermostat. The oil pipe to the oil filter head is connected to the same side of the thermostat and has a straight union screwed into the filter head. The other two pipes are connected to the oil cooler.
There is no facility to fit screwed unions to the thermostat. The oil pipes are just pushed over the stubs and secured with a jubilee clips.
Oil resistant hose must be used.

oil thermostat..JPG (1.68 MiB) Viewed 6297 times

The lower right union (inlet) goes to the block and the top left union goes to the filter head.
The two unused stubs go to the oil cooler. All connections are secured with jubilee clips.
The two pipes with a RED tie wrap are the same pipe but cut in two.
You could cut the metal pipe that goes between the block and filter head but I would suggest that you use the proper barbed unions for oil pipe security (see photo above).

[ndevans]

Have to admit, I'm not minded to fit an oil cooler. Extra complication, more to go wrong, and if I understand correctly, it isn't going to fit on the Marina block anyway.

Timeline of head gasket failures is as follows:-

Composite gasket fitted July 2016, failed Sept 2018, ~5000 miles.

Copper gasket fitted Aug 2019, failed Nov 2020, ~1600 miles.

Copper gasket fitted Dec 2020, failed June 2021, ~1400 miles.

All 3 gaskets are from 3 different suppliers.

I am taking the head in for squaring off tomorrow, and will fit another copper gasket. If/when that fails, I'll consider stripping the block and squaring that off.
In the meantime, I'll check ignition timing. I did notice my temperature gauge hovering around 195-200°F winding along slow A roads on the way to Exmoor, but as it was a hot day, the gauge is old, and I haven't really run it in hot weather since fitting it, I didn't think much more about it. It's entirely possible that it's pinking a bit, but I'm not hearing it at speed.

[philthehill]

To fit the oil thermostat to the Marina engine you just need the right adapter.
Here is the right adapter as fitted to my Minor which has a Marina block.

WDF oilflter take off.JPG (1.72 MiB) Viewed 6282 times

[jagnut66]

You could cut the metal pipe that goes between the block and filter head but I would suggest that you use the proper barbed unions for oil pipe security (see photo above).

Thanks for that Phil, I have ordered two oil thermostats, one for each Moggy. I will be fitting it inline with the coolant hoses, the metal pipe from block to filter housing was dispensed with when I fitted the oil coolers.

Unlike you I had a 1275 (ex-Midget) engine overheat (cooking the oil) and ended up with little end rattle / knock.
This occurred on my first motorway journey with the 1275 fitted (in replacement to the original 1098 unit).
Prior to my fitting it, the 1275 had been professionally rebuilt and was in good order initially, running well on 'A' and 'B' roads.
After my disaster on the motorway I sourced another 1275, also an ex-Midget unit, though not rebuilt this time. I fitted and serviced it but this time I included an oil cooler in the set up, as fitted to the MG Midget, rather than following the original Minor set up without one, which is what I had done the first time.
I had no further issues with overheating on motorways afterwards.
Best wishes,
Mike.