free hit
Argh, head gasket... - Engine/Ancilliaries - The Lotus Forums - Lotus Community Partner #ForTheOwners Jump to content


Argh, head gasket...

Neil Potter

Recommended Posts

Evening all,

Looks pretty much like my head gasket has given up the ghost.  I spotted some mayonnaise on the dipstick in the autumn and put it down to condensation in the tube (oil at the cams was fine).  Might have done thirty miles since then as the interior has been out for reconnolising.  But I started her up tonight and watched the oil get gloopier through the filler cap; obvious white swirls in there.  All very depressing as I'm really looking forward to some tours this summer.

Engine has done just over 100k miles, but is in reasonable shape I think for that mileage.  Although I haven't done a proper throttle open compression test on the hot engine, before I knew much about these things I did one on closed throttle when cold and got readings of 90-105 psi each.

A couple of questions:

Any straws to clutch at here?  It seems pretty conclusive to me so is it worth doing one of those exhaust-gas-in-the-coolant chemical kit things?

And can a HG be done in situ?  If it's an engine out job then it might make sense to bite the bullet and get a rebuild.

cheers all,


Link to comment
Share on other sites

Upgrade today to remove Google ads and support TLF.

If it's water-oil failure rather than combustion chamber-oil or combustion chamber-water, then you could also check what is in the coolant tank as there would be contamination and so show up as a film on the top but may not always show via the coolant gas sniff test kit. To be more conclusive you'd need to also perform a coolant pressure test and a full-throttle compression test (maybe even a leak-down cylinder test).


Whether it's technically possible to do in situ (it is if you dislocate the engine mounts), it's just not convenient so if lifting the engine& gearbox out is an option for you then go that way.


Link to comment
Share on other sites

Thanks guys. 

The crank case breather WAS blocked; I'd put a filter on it a couple of years back rather than have it push oil mist into my turbo and carbs.  The filter was full of gunk, as was the green thing with the gauze in it.  I noticed this after I first caught the traces of mayo on the dipstick.  Assuming that it was HG failure i was thinking the blockage was the effect rather than the cause.

There does appear to be a bit of a film on the coolant though, which would seem to settle it.


Link to comment
Share on other sites

If you ve only done 30 miles, I'd run it for a good few more at temp before making a decision...condensate in the oil shows for quite a while, and if it was ok before layup...

obviously check coolant every few miles if poss to minimise risk if it is the HG. A leak down test is always a good one though if you've got the kit.

by comparison, mine CTd at 110-115 on a cold, closed throttle test before doing it properly, when I got 150-160.( cold) with the leak down kit.

good luck!

Link to comment
Share on other sites

Bad news Neil,

However, ;if it is mayonaise, water in the oil, at the dipstick and under the oil filler cap, but no white smoke or other things, you might try a can of bars leak original in the water circuit. It does not hurt or do bad things and it might do the job. I had white drap some years ago, and I opened up the engine, did a head revision, put a new headgasket , have an engine with fantastic compression, running like new after  that but....still mayo.... A bit desparate  I put a can of bars leak in it and oddly enough it stopped .

All was fine until I did my maintenance a year later and rinsed the watercircuit, put fresh coolant in and all of a sudden, drap again. So I used a can of bars leak original again and all is fine since. I use the car often.

I didn t believe in that stuff before, but in my case it does the job well. Give it a try and let us know

Edited by gvy
  • Like 1
Link to comment
Share on other sites

1 hour ago, ian29gte said:

If it were me, just to be sure, I'd do a compression check, and a coolant system pressure check next.

This! And a sniff test!

Block Testers a blue coloured reagent that turns yellow when exhaust gases are present by JSPROD

  • Like 1

1982 DeLorean DMC 12 #16327, 1999 Lotus Elise, 1998 Lotus Esprit GT3 #2272, 2011 Lotus Evora S, 2013 Lotus Exige S,2016 Lotus Evora 400

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...