Another head gasket failure!

[wayne]

As already said above by Fetnas, The ITM gasket has different cut outs to the Lotus Turbo gasket.
So may be a N/A gasket. I have a couple of the Lotus N/A ones back in the UK, I will try to get my sister to take pics and send them to me so as I can compare.

I just happen to have both the ITM gasket kit and Turbo head gasket here.
Pics are not great, just thought I'd include them to this thread so others can see the difference.
Hope it helps someone

20180202_044304.jpg

ITM kit

20180202_044326.jpg

Lotus part

20180202_044343.jpg

lotus part

[Fetnas]

Thank for posting the photos Wayne,

My supplier, Lotus Marques of Melbourne, dropped in at my work place and personally swapped over the ITM NA gasket for a genuine Isuzu turbo head gasket, complete with original packing, and looking at your better quality photos, looks exactly the same at the Lotus part, which it should as they woudl have both come from the same manufacturer.

Based on the personal service Steve has given me and considering I now have the full gasket set for just a bit over $100 Aus, I'm very happy. He did give me a discount as he was able to get a saving by bulk ordering from ITM, the normal price is closer to $160, but even then he's great value as I didn't have to pay shipping from the other side of the planet.

Next step, take the head off and see what I find!

Steve,

The first signs of HG failure in my car was a pressurisation of the cooling system, in hind sight, it had probably been like that for a while, but I hadn't use the car much so I didn't really pick it up. It wasn't enough to cause the relief valve in the header tank cap to purge and overflow, but it meant there was always air in behind the thermostat which could be heard sloshing when squeezing the hoses. The Gasket only let go after using the car as my daily drive for 3 weeks with some spirited acceleration. Thankfully the gasket hasn't blown between the oil galleries and the water jacket but from the cylinder to the cooling ports and between cylinder 2 and 3. It sounds like you may have early stage gasket failure after all if your header is overflowing, but I'd try a new cap first as the relief valve may no longer be to spec and opening too early. If you have access to a cooling system pressure tester, I'd run the engine up to temperature with that attached to the header to see if the pressure goes beyond the relief valve rating. If it does, something else is going on that will need to be looked into.

Good luck and i hope your gasket isn't the problem.

[Fetnas]

For anyone whose interested, attached below are photos of the Isuzu head gasket and the GM part number.

Gasket.jpg

Part number.jpg

Perhaps I should put this in the parts cross reference as well, if it isn't already there.

[Rambo]

Might be as well putting an entry in the WikiLEC ??

[Fetnas]

More parts references. The 'new old stock' fuel pressure regulator I found on Ebay arrived. It's exactly the same as the unit that's in the car. Photos of is and the original box it came in below for info.

Fuel reg.jpg

Fuel reg 2.jpg

There's a stack of numbers on the box, the main part number is 17112273. I'm not sure how useful the other numbers are, but hopefully this info will help others track this correct part down in the future.

[Brit-Car-Nut]

Unfortunately, that is the correct part number but what you got is a very OLD version of it. Basically, New OLD Stock.

It is actually still a good number but was replaced by the newer part design (keeping the old number) years ago. Good find, but I would be worried that the diaphragm might be dried up.

[Fetnas]

Well, it's probably no older than the one in the car and it's seen no use! I have opened and restored the vacuum actuator for the ancillary air intake butterfly as the spigot had been broken off (a temp fix I did early on was still holding but only just). The rubber of that diaphragm was still supple and showing no sign of drying out. At the very least, the new old item should be better than the old rusty one in the car.

[Brit-Car-Nut]

I agree, but the newer version (PR92) will fit with no big issue too and they can be found for cheap prices - $17.00 delivered in the US.

Still a good find. I found a couple several years ago AFTER I replaced mine with the newer style.

[Fetnas]

So, the head is off. It's not this first time as it looks like the head has been cleaned with sand paper in places! I can still see the original machining marks, but these sanding scratches don't look good! They're only local, but all the same, it's not supposed to be like that. I had a quick look through the extensive service history I have for the car and found that the head gasket was replaced in 2004 by Kelvedon Lotus. The quality isn't quite what I would have hoped for!

Anyway, I've cleaned off the old gasket, and although I couldn't clearly see where the gasket had failed between the cylinders, the gasket did have signs of coolant seeping into it on the intake side between cylinder 1 and 2. So that required the gasket be replaced if nothing else. I've done a preliminary check of the flatness (I need a longer straight edge) which seems to be 0.1mm at the moment. That's still in spec but the largest deviation is between cylinder 2 and 3. I'm leaning towards getting the head machined but I'll leave it until I've checked the flatness properly. I'll probably also get the machinist to relap the valves and replace the seals for me whilst their at it. There is a place very close to work that has a very good reputation and is the place the local lotus supplier has used for the last 25 odd years! Only problem is, they're normally quite busy! Good things come to those who wait!

Does any one have some recommendations for the removal of the carbon build up under the cam cover and on the cam bearing caps? I'm leaning towards also dropping the sump to clean it out and repaint, as there's a bit of rust on the outside which should be dealt with.

So much project creep1

[Brit-Car-Nut]

Hand cleaning the inside of the valve cover is safest. Use Carb cleaner on a very clean rag. Do NOT consider soaking it or blasting it. there is mesh around the PCV valve area that needs to be left alone. Blasting media can't be cleaned without modifying the cover and heavy solvent soaking might clean out softer accumulations but it might "free-up" any heavier carbon that could end up in the oil later on. If you want to do a deep clean, then you need to drill and tap the retainers and then loctite screws to hold it back together again. I suppose you could drill them out and use pop-rivets to reassemble, but machine screws are safer (my opinion).

Cam caps clean up well in carb cleaner or lacquer thinner. Obviously, keep track of the location of each one - they only fit correctly where they came from.

I would get the head lightly skimmed to clean up the sand paper scratches and get it as smooth as possible. Just stay within the allowed specification.

[clemo]

I would get the head lightly skimmed to clean up the sand paper scratches and get it as smooth as possible. Just stay within the allowed specification.

THIS

[lotusflasherman]

THIS

or THAT ?

[Fetnas]

I'm going for this & that!

I'll be dropping the head off to get skimmed tomorrow. It still has the valves in it, I hope that isn't a problem. I'll be removing the valves and lapping them in after the machining. Once I've cleaned off as much of the varnish I can and overhauled all the hydraulic lifters, I can start slowly putting it back together.

On a side note, whilst researching head gaskets, I came across a head gasket failure diagnosis information sheet produced by Glaser. Using this I was able to confirm and identify the failure point, which was quite subtle. It was the slight local darkening of the fire ring that confirmed it. If I hadn't found this info, I might have missed the failure point. That said it is where the head flatness deviated the most (approx 0.12 but my straight edge isn't long enough so it's probably slightly more), so it makes sense.

This is the link to the page where the PDF can be downloaded. A useful resource for anyone else going through this process.

glaser.es/EN/Products/Cylinder-head-gaskets.aspx

[Fetnas]

I picked up the head today. I'm very happy with the result. The machinist took off 5 thou (imperial? how old school!) or 0.127mm which was just a bit more than what I measured. The surface is excellent, probably good enough to use a MLS gasket! I can't see any machining marks in the surface where as the factory finish was defiantly still visible despite the sanding.

The ultrasonic cleaning I requested has removed almost all the contamination, with only a little carbon left in the combustion chamber. I'll get rid of that by hand.

Machined head.jpg

Now I wait for the valve spring compressor I've ordered to arrive so I can get onto lapping the valves.

[lotusflasherman]

The ultrasonic cleaning I requested has removed almost all the contamination, with only a little carbon left in the combustion chamber. I'll get rid of that by hand.

This stuff is the solvent to shift that carbon ... spray it on, wait a minute, wipe it off... use a toothbrush on stubborn bits so nothing gets scratched.

[lotusflasherman]

Good for cleaning pistons too .... before and after photos..

piston dt.jpg

piston bk.jpg

(it's a Subaru EJ25 engine and I'm just about to clean the block before fitting the head gasket)

[Giniw]

Seems effective!

[Fetnas]

Hi Lotusflasherman,

I've got a can of Carb clean and have been using it here and there along with lacquer thinner to remove buildup on the engine internals, I haven't cleaned the piston tops yet, but they actually don't have much build up. The edge of the pistons are clean for about 10mm with only a light film of carbon across teh rest of the piston. That will be cleaned off before the head goes back on.

The other discovery was that 2 of the exhaust side hydraulic lifters were completely seized and required a bit of compressed air pumped into them to get them to pop apart. These lifters were the first and last in the run, where I assume they get slightly less oil flow from the central feed point. I'll be using high quality synthetic oil in the lifters as they go back together, so that should reduce the build up of gum in the future. I've only used synthetic oil in the car, I'm pretty sure the build up is from before my time owning the car.

My dad's been lapping the valves, replacing the valve seals and cleaning the lifters for me as I just don't have the time with a toddler running around, although I would have liked to do it myself.

It's slow going, but progress is progress.

[lotusflasherman]

Hi Lotusflasherman,
....My dad's been lapping the valves, replacing the valve seals and cleaning the lifters for me....it's slow going, but progress is progress.

Tell Dad I told him to get a move on...

[Fetnas]

Finally made some good progress over the last couple of days. I'll let the photos below do the talking.

Block before cleaning.JPG

Block after cleaning.JPG

Head before cleaning.JPG

Head after cleaning.JPG

Heat shields.JPG

The head has been completely dismantled, all carbon and lacquer removed from all parts and reassembled with engine assembly lube (weird stuff). The piston tops were cleaned with non scratch scourers and WD40 which worked really well. The block surface was cleaned with a sheet of 1200 grit wet and dry sand paper wrapped around a mirror for flatness and WD40 as a lubricant with the pistons half way down the bores and a rag on top.

The gasket mating surfaces were cleaned with brake clean and a rag with clean oil wiped over the cylinder bores prior to assembly.

The was so much build up under the cam cover that I've had to go the soaking method despite Brit-Car-Nut's advice. Almost 1mm thick in places. I have it in a bath of water based degreaser and with a bit of elbow grease, have removed almost all of the visible gunk. I have a small pump circulating the degreaser through the ventilation chamber in the hope it can shift the muck in there. Having gone this far, if i can see that gunk is still present in the chamber, I'll have to drill out the rivers and split the cover to make sure all the crud is gone.

If a jobs worth doing etc!