Just no luck - HGF No 2 - oil in coolant

[jamherber]

So bit of potted history on where we with our SE. We purchased it last September with mild head gasket failure (corrosion on head causing minor coolant breach into cylinder 4).

Spent the next 6 months stripping the top end down & upgrading the cooling system. Had the head welded, skimmed and fettled by a trusted engineer that I've used for many engines over the years. We were meticulous with the reassembly (even down to stripping and ultrasonically cleaning the tappets). New engine gasket set (including the head gasket) from SJS. Block checked for flatness. Injectors sent away to be cleaned, checked and serviced. Turbo rebuilt by a local company etc etc. Really went out of our way to do a proper and lasting job.

So fast forward to now - engine has run brilliantly for 1.5k miles with no issues at all (its my sons car and he has been using it as his daily car). Strong, smooth, no oil consumption, no coolant usage. Then last week oil level started dropping. Son topped it up and thought nothing more of it. Check it again yesterday and oil back at minimum - opening header tank to find oily sludge so can only assume the HG has failed but this time between the head oil feed to a waterway. Cylinder compressions all spot on and equal. Car has never over heated (certainly since our rebuild). The rate the oil is entering the coolant circuit is now very significant so obviously the car is off the road again.

So questions I have are-
1. Is this a known mode of failure with aftermarket head gaskets?
2. Given the OEM ones are long gone, what make should I use?
3. Is there anywhere else where we could be getting oil & coolant mixing (ie is there a known weakness in the block whereby an oil gallery can crack and leak into the coolant circuit?)

Really gutted and dejected at the moment as we'd put so much time and effort into getting it right, just feels like a kick in the nether-regions, particularly given how well it has been running.

Any help or ideas really appreciated as we are still learning the car and this engine.

Thanks in advance.

[Steve A]

Sorry to hear about what you're experiencing. It certainly sounds like you were very thorough with the rebuild.
You really should be reaping the rewards of all your efforts.
In the past, I have spoken on the phone to SJ's regarding the head gasket they are selling, and they insisted "it was the same gasket as it had when it left the factory".
Not having changed my gasket before, I can't throw any light to clarify this either way, but hopefully somebody on here who has done it, should be able to help

[Tuga2112]

i have changed a head gasket, about 7 or 8 years ago. Im sure Dave recalls the dozens of phone calls for help with that task.

I used one from SJ. and that is still running on the car. now with an everest chip and no problems at all.
neither the head or the block were skimmed back then, and thats as far as i can tell.
I dont have records of it that i remember, and i dont think the "quality" of the stock can be assumed from that experience, because theres a good chance i used new-old stock. where something aquired in the past couple of years could be a re-manufactured part to the original spec.

as far as the original questions. be mindful this comes from someone with limited understading

1 - dont recall ever seeing a similar case to yours from keeping ana eye on the forum and facebook groups.
2 - theres a post i read in the past where someone declared they used the impulse turbo gasket (from rockauto) in their car, it was confirmed at that point they have different waterways, and the person didnt track the car. but they didnt folow up with any issues.
finding that post may be very valuable to you, but unlikely to be easy given how the forum search tools work. but maybe you can take advantage of chatgpt ?
3 - not that im aware of, mixing oil with coolant is a rather rare topic to come up across all platforms in my experience... at least on the M100 engine... cant say the same about Rover K series .

[jamherber]

Thanks for the replies.

I did E-mail Steve at SJS a couple of days ago but heard nothing back yet.

Can only assume the breach is around the elastomer tear drop shaped seal on the head gasket, as that's the high pressure oil feed to the head (plus is very close to a waterway). If it was say corrosion on the block face in that area (although I did check this), I would have expected it leak into the coolant from day 1, rather than happen relatively suddenly, as appears is the case.

I'm hoping it all will be revealed once the head is off again. I suppose at least this time we know what we are doing and everything should come undone easily!

Obviously reluctant to put the same make of gasket back on but it seems chatting to the various specialists, there is little choice (although I can't be sure, it looks like one from Classic Lotus Parts is the same as the SJS one). Mike from SWLC has an Apex head gasket coming into stock but looking back through some of the old threads on here, it seems this may be the gasket previously supplied Rock Auto that has the same part number for a N/A as a Turbo, so I'm not sure. It's a bit of a minefield for sure.

I'm trying to message SimonP on here as he did list a head gasket on his parts clear out advert last year but for some reason, my message to him won't send. Hopefully he may read this thread...

Unfortunately, due to work commitment we probably won't have time to start the strip down until mid September though

[niall]

Sounds like you have had some very bad luck.
I have never changed a head gasket on a M100 but recall from the days when I had more primitive cars like mk1 minis that advice was always to retorque the head gasket bolts after a short period of running. In those days I had no torque wrench so it was always muscled down tight immediately.
Did you retighten after some running?

[Tuga2112]

I'm trying to message SimonP on here as he did list a head gasket on his parts clear out advert last year but for some reason, my message to him won't send.

he doesnt check the forum on a daily basis. but he does reply. it may just take a couple of weeks tho.

[TorqueHorse]

Obviously reluctant to put the same make of gasket back on but it seems chatting to the various specialists, there is little choice (although I can't be sure, it looks like one from Classic Lotus Parts is the same as the SJS one). Mike from SWLC has an Apex head gasket coming into stock but looking back through some of the old threads on here, it seems this may be the gasket previously supplied Rock Auto that has the same part number for a N/A as a Turbo, so I'm not sure. It's a bit of a minefield for sure.

Sorry you are going through this, and I empathize with you!
Check out a recent post on my main rebuild thread.
I only had combustion gases leak into the coolant, not oil, so I don't have any advice on what might have been your failure point. But I share your pain of not being able to find the "original" turbo gaskets. Not totally related to an oil/coolant failure, but I've decided to enlarge some of the coolant holes in the headgasket to match what I visually see in a picture of the "old" turbo gasket, since all the gaskets seem to be the same profile now. I have zero data on the efficacy of this approach, but I'm hoping to have it going before Sept. Hopefully, if it fails, it'll fail early and I can have something to report

also, re this

always to [retorque] the head gasket bolts after a short period of running.

I guess as you are tearing it down, you could see if the bolts tighten up any more to get to the torque spec.

Good luck on being able to find out exactly where your oil leaked from, and getting back on the road with hopefully just a new gasket!

[jamherber]

I'm trying to message SimonP on here as he did list a head gasket on his parts clear out advert last year but for some reason, my message to him won't send.

he doesnt check the forum on a daily basis. but he does reply. it may just take a couple of weeks tho.

The weird thing is, the message seems stuck in my 'outbox' and never gets to the 'sent' folder so it looks like it won't get to him.

[jamherber]

Regarding re-torqueing, modern engine and gaskets shouldn't really need that and given all our compressions are still good, it seems unlikely to be a clamping force issue for our failure but I guess it would be interesting to check the torque at the point of strip down anyway.

[KenS]

I'm trying to message SimonP on here as he did list a head gasket on his parts clear out advert last year but for some reason, my message to him won't send.

he doesnt check the forum on a daily basis. but he does reply. it may just take a couple of weeks tho.

The weird thing is, the message seems stuck in my 'outbox' and never gets to the 'sent' folder so it looks like it won't get to him.

This is normal, a message stays in your outbox until the recipient opens/reads the message, so its all good, but waiting for the response.

[dapinky]

I know I've put it up before, but here is a photo to show the differences between a Turbo and an NA gasket from Lotus....... I don't have pictures of any aftermarket versions, but it may give you something to compare them to.....

HG comparison.png

[jamherber]

I know I've put it up before, but here is a photo to show the differences between a Turbo and an NA gasket from Lotus....... I don't have pictures of any aftermarket versions, but it may give you something to compare them to.....

HG comparison.png

Thanks - that's useful.

[KenS]

Hi Dave, I think Lotus have supplied a few variants of the Turbo Head Gasket A100E6104S which complicates identification. Looks like the teardrop shaped water way holes at each end may not be a key feature, but an important feature? TorqueHorse' post shows the Lotus gasket with round holes https://forum.lotuselancentral.com/viewtopic.php?f=33&t=28215#p362171.
The Turbo head has teardrop waterways at one end, and the block has them at both ends, so it is odd that Lotus have sold HeadGaskets with round holes at both ends which could restrict water flow? The last HG I took out had round holes both ends

TorqueHorse' picture:

turboHGsml.jpg

[dapinky]

Thanks Ken - all information is good, even if it's contradictory! I haven't bought a HG for many years now, but back in the day I bought the last 10 NA gaskets that Lotus had in stock for £2 each.... and no-one wanted them, so I sent 6 to USA for Impulse guys, gave Clemo 3, and kept 1 for myself......

..... at the time, turbo units were still considered to be "stock" items, so I bought 3 of them (I used 1 straight away)......

..... and now you can't seem to get anything which matches either of the ones I have! (even if they are sold as being Lotus parts with the same number) - it sure doesn't make it any easier.

[TorqueHorse]

Yeah, when I first got my car a few years ago I remember a big debate about if the "turbo" gaskets were still available. At that point I thought it was just if a part with the part number was available. It seems like there was a brief period where you couldn't get one with that part number, but then the time passed, and I was able to get one with the Turbo spec part number.
It wasn't until this past year that I saw Pinky's actual photo's of the old Turbo ones he'd had. That's when I realized that even if a part with the part NUMBER was available, that didn't mean it was exactly the same profile as all the other ones that have had that same part number in the past.

[Hector2021]

This is absolutely terrible news especially since you clearly know what youre doing and have been so diligent in doing it. I thought mine was showing off symptoms about a year ago with froth in the header, but it never manifested itself as anything worse than me eventually putting it down to air in the coolant circuit.
A real take away from your experience that others might learn from is if once you embarke on the journey again, you post a picture of the fault, or head gasket so it's clear to thers what this weak spot may be.
Good luck with your next 'deep dive'

[jamherber]

So after struggling to find the time to look into this, finally started.

Did a hot compression test to start with, all fine and spot on at 160psi per cylinder. Car is running beautifully on start-up etc.

Then drained coolant - here's what it looks like:-

IMG_8820.JPG

So guess it's head off again - must be a small breach from block oil feed to a waterway but no idea why this would occur as head was skimmed and block cleaned up meticulously.

Just pray we can see the cause of the issue on disassembly as don't want to be doing this for a third time

[Tuga2112]

just a idea.

get the oil out as well. im thinking it would give you an indication if the water is getting into the oil as well as the opposite direction.

im considering the possibility that you had oil in the waterways internally. and everything may be fine. but you may need to just flush the coolant a few times to get all the pre-hg change oil out

[jamherber]

just a idea.

get the oil out as well. im thinking it would give you an indication if the water is getting into the oil as well as the opposite direction.

im considering the possibility that you had oil in the waterways internally. and everything may be fine. but you may need to just flush the coolant a few times to get all the pre-hg change oil out

Unfortunately there is way too much oil in the coolant for it to be residue and over the ~1500 miles the car covered after the rebuild, the oil kept having to be constantly topped up so we now know it was just seeping into the coolant circuit.

We'll drop the oil anyway though. Hopefully we may get the head off this coming Sunday, all being things being equal, and I just hope the cause is obvious!

[TorqueHorse]

That's so frustrating!
I've still got some leak somewhere in my head too after my rebuild, but I scratched the face of the head during reassembly, so I'm hoping that is the problem.
Good luck on identifying the culprit!!!
I don't know if this works, but I've heard that using copper spray gasket over the surface of the gasket can also be an additional belt & suspenders type of insurance for a good seal. I was planning to try it when I do mine again.