Another head gasket failure!

[Fetnas]

This follows on from a topic under ignition and timing.

So after doing quite a bit of preventative work on the elan (brakes lines, timing belt, water pump, brake master cylinder), and some reactionary repairs (new CAS, new ICM) I now find that the head gasket has failed.

I did a compression test on all cylinders, had 9.5 bar in cylinder 1, 6.5 bar in cylinder 2, 8 bar in cylinder 3 and 9.6 of bar in cylinder 4. These pressures are all probably a bit low, but the guage was cheap one, so the absolute figures aren't of concern, it's more the relative low pressure in cylinder 2.

I also did a leak down test. Cylinder 1 had almost no leakage, 2 had high leakage, cylinder 3 leaked but not as bad a 2, and cylinder 4 was leaking past the rings into the crank case, even after putting some oil in the cylinder. Not sure what's going on with 4, but the head has to come off anyway, so I'll inspect it for further problems then. I find it odd that the compression is good in 4 but the leak down was bad?

I've read through forum posts about the available gaskets, so I know that the recommended option is the official Lotus item from SJ. I plan to get a full gasket set, but I don't understand why the turbo gasket set is almost twice the price of the NA set? Sure there are more gaskets in the turbo set, but not that many.

Oh well, it's only money and once it's done, I know it'll be good for another 20+ years. Then it's time to drive the thing!

[clemo]

Oh man sorry to hear of your engine woes .Especially with all the work you are doing at the mo . Though as you say at least you are future proofing your car .

The NA has different waterway or something like that . So it wouldn't fit .

I will be going up to SJ's next week if i can be of any help to you .

[Fetnas]

Hi Clemo,
Thanks for the offer with you SJ visit.

I just found yesterday that a local Lotus specialist that's very close to where I work stocks a head gasket set. I'll give them a call next week, much better value than SJ also. That said, if I'm not 100% happy with the quality of the gasket, I might still go the SJ way. It's good to have options.

[alan e]

I will be in Melbourne at the end of April if you can wait that long I can bring the kit over with me that will save you the postage cost if its any help.

[Fetnas]

Hi Alan, thanks again for personal courier offer, but after speaking to the local supplier yesterday and ending up having a 10 minute chat with the owner, I'll be getting the parts through him. So no need to deal with shipping from the UK.

[Fetnas]

So I spent 1 day this weekend working on the car. I've drained the coolant, removed the intake manifold, separated the injectors from the intermediate manifold and removed the manifold. I've also removed the auxiliary belts, engine mount and timing cover exposing the timing belt ready for removal once the head is ready to come off.

A couple of questions, should the return line fitting to the bottom of the fuel pressure regulator be a solid and rigid fitting? On my car, although the nut is done up tight, the return line moves around a lot in regulator. It wasn't leaking fuel, but I'm surprised that's the case, it doesn't seem right to me or my dad.

How is the metal return line supposed to be fixed to the plastic line? My car has a inch long bit of fabric covered fuel line at this junction with a spring clamp on one end and a screw tighten hose clamp on the other end. It doesn't seem to me that the car would have left the factory like that.

The new gasket set has been ordered and should arrive this coming week. The following weekend is a long weekend in Aus (bank holiday for the UK readers) so I should have the head off with out a problem. I'm planning on changing the valve stem seals whilst the head is off, not because they're leaking but because it makes sense to do it now rather than have to deal with possible leaks in 50,000 kms time. I might also get the head skimmed and valves reground if look like it needs it. The head shouldn't be warped as the car has never overheated whilst I've had it. I'll know for sure next weekend.

One other thing, I'm going to replace all the vacuum lines whilst doing this work, any ideas as to how much I'll need to replace everything except the line to the heater control?

Head gasket work is a big job on a turbo car with very limited access!

[HJ2]

Good work, you're getting there!
And yes, it IS a lot of (rewarding) work

[simonbuk]

Did you get a genuine Isuzu Lotus head gasket ? Apparently they are the only ones that work (a long time).

The other copy head gaskets are based on the NA engine (allegedly). Only saying as i would hate for you to go through all this work and regret it later.

Mine is just about to ge done (for differenf reasons) so looked into it a bit.

[Brit-Car-Nut]

If you look up the head gasket from the aftermarket manufacturers, go to their reference of other cars the gasket fits and you will see the GEO Storm, Isuzu Impulse, Isuzu Stylus and they are all non-turbo engines. The turbo gasket has different water ports and better cylinder crush rings. The water ports are are different shapes than the NA version which helps cool the head better. I don't know about in the UK but finding a real Isuzu Impulse Turbo head gasket is near impossible.

Isuzu part numbers:

GASKET; CLYL HD
8944296261 1989/11 - 1991/09
INT GRADE XS (RBC) EXC. TURBOCHARGER

GASKET; CLYL HD
8944636780 1990/06 -
COUPE INT GRADE RS (RBD)TURBOCHARGER

It makes a difference.

[Fetnas]

I have looked into the gaskets available. The turbo gasket has an orange oval seal in 2 corners and also has a small tab on one end that indicates it's a turbo gasket. I have quizzed the local supplier about this and he is has a very reputable business that's been around for many years. He used to work at Lotus and his aim is to supply parts that are equal or better quality than the original equipment.
I'll be inspecting the gasket to make sure it's correct when I pick it up, but I don't expect any problems.

[Simon_P]

The key thing is the Tab on the end of the head gasket to denote turbo, which is I believe a different thickness. Of course Isuzu wouldn't have made the gasket themselves, so the big name gasket companies should be equally good I'd go for one that is made from the same material as the original looks like graphite, can't remember the name of the stuff.

Yes the petrol pipe is ike that!

You will be amazed at how little wear the valves have, just clean off the crud with a wire brush on the angle grinder or bench grinder, then lap them by hand.

Yes it is worth changing the stem seals. It is also worth cleaning out and rebuilding the lifters see the write-up.

Have fun!

[Fetnas]

Hi Simon_P,
Thanks for confirming the fuel return line is as it should be. I guess I was expecting a metal fitting, but it's only low pressure so all good.
I was hoping to avoid clearing the hydraulic lifters, that looks like a slow fiddly job, but as I don't want to have to crack open the engine again for as long as possible, I'd hate to have a lifter gum up! I'll add this job to the list. On top of cleaning, derusting and painting all the little brackets and pipes, project creep is a real bugger!
I've extracted the exhaust manifold and turbo over the last weekend. All that's left is to pull the cam cover, remove the timing belt and undo the head bolts! Getting closer to the root of the problem, just waiting for the new gaskets to arrive!
I've also just picked up a new old stock Delco fuel pressure regulator with the correct side entry vacuum port on ebay. There aren't many options around that work with out modifying the lifting bracket, so finding the correct part (advertised for the Isuzu Geo Storm 1.6) was a pleasant surprise.

[stevieg8571]

Hi all,

I'm hoping to get one of the engine gasket sets from Rockauto (as I'd like to have my Head Gasket (HG) changed) and wondered if anyone has any experience of them? There's two listed for the Impulse RS (Turbo), a Fel-Pro and an ITM set, should I go for the most expensive or are they much the same? Both include valve stem oil seals which will be changed at the same time as the HG.
Just so you know my HG is currently fine, I think, but I want to change it due to it being 27 years old.

Thanks, Steve

[Fetnas]

Hi Steve
I wouldn't recommend the ITM set. I've just received this gasket set and although it looks like a well made gasket, with copper sealing washers for the oil galleries which I haven't seen in any other images, it is not the Turbo gasket. I checked the ITN website, and they only make the normally aspirated gasket which isn't suitable for the turbo.
My supplier has been made aware of this and will swap the ITN head gasket for a turbo gasket he had in stock.
I don't know anything about the Fel-pro, but I would recommend doing a check on the manufacturers website to see if they have 2 part numbers for the head gasket ie turbo and NA. Also, see if you can find a photo of the Fel-pro to confirm which it is, if it's a turbo gasket, it should have large oval orange O ring sealant in 2 diagonally opposite corners.
That's my 2 cents on the matter, good luck.
P.S. I just checked the Fel-pro website and the image is of a turbo gasket, so of the rock auto options I'd recommend this one over the ITN, but bear in mind that I've no experience with this brand so can't comment on quality.

[Brit-Car-Nut]

Others have used the Felpro gasket with dismal results. You can't trust anyone's pictures. Just order one from LOTUS and you will be better off. I have two or three sitting on the shelf waiting for the eventual need. I am in the US and I have to order from a UK dealer, but it is well worth it.

[Brit-Car-Nut]

Hi all,

I'm hoping to get one of the engine gasket sets from Rockauto (as I'd like to have my Head Gasket (HG) changed) and wondered if anyone has any experience of them? There's two listed for the Impulse RS (Turbo), a Fel-Pro and an ITM set, should I go for the most expensive or are they much the same? Both include valve stem oil seals which will be changed at the same time as the HG.
Just so you know my HG is currently fine, I think, but I want to change it due to it being 27 years old.

Thanks, Steve

DON"T DO IT! do a deep search on LEC and read all of the failed projects to understand the head gaskets are worthless. The other gaskets are fine, so buy one of the less expensive sets off eBay and throw away the head gasket and get one from Lotus - either from a dealer or SJs or SW Lotus. They are approved and only sell the correct part.

[lotusflasherman]

Hi all,

I'm hoping to get one of the engine gasket sets from Rockauto (as I'd like to have my Head Gasket(HG) changed)

What ??? "Like to" ??? only do it if you NEED to. It's not a routine service item and "If it ain't broke, don't fix it" is a good rule to go by ...

[Rambo]

Hi all,

I'm hoping to get one of the engine gasket sets from Rockauto (as I'd like to have my Head Gasket (HG) changed) and wondered if anyone has any experience of them? There's two listed for the Impulse RS (Turbo), a Fel-Pro and an ITM set, should I go for the most expensive or are they much the same? Both include valve stem oil seals which will be changed at the same time as the HG.
Just so you know my HG is currently fine, I think, but I want to change it due to it being 27 years old.

Thanks, Steve

Nah, don't touch it, like Phil says above. I've never had to change the HG in any of mine. By all means do a sniffer test, compression test etc.... to allay (or cofirm ) your fears but don't change things if they don't need it. You will only open up a can of worms

If you're looking for something to get your teeth into I suggest you check when the cambelt and associated paraphernalia was last changed

[Fetnas]

As I'm halfway into job, I'd agree with Rambo and Lotusflasherman. If you don't need to do it, leave it as is as it's a very time consuming job with lots of difficult to access nuts and bolts. There will be cursing and grazed knuckles!

[stevieg8571]

Thanks for all the replies.

I'll take your advice and leave well alone until needs be. The header tank bubbles over if I let the engine idle until the temp gauge shows over 2/3 so I was thinking air could be getting in through the HG. I'll have it tested near MOT time. There's no visible signs of failure though , ie: mayo looking oil, oily water or white smelly exhaust (as 2 previous old Vauxhalls have done).

The timing belt's only done around 5000 miles since it was last changed, along with the water pump, tensioner & pulley so all's ok there.

Thanks all.