cylinder head / timing kit

[johnj]

Hi All

I've just been told the car needs a new head gasket. The car has been using water but there was no emulsion on the oil filler cap so I was not expecting this news. My mechanic says if I buy the bits required he will fit them. He is not an expert so is there anything he needs to know to help him? Is there a kit available that contains all the pieces I require? If not what do I need? What are the best bits and where is the best place to buy them at the moment?

[robertverhey]

Just out of interest, What evidence is that diagnosis based on? Overheating? Pressure test of cooling system? Water in oil? Oil in water? Oil in exhaust gas? Water or steam in exhaust gas? Bubbling in coolant reservoir? One clean spark plug electrode? Loss of compression? Leak down test?

[Rambo]

I've just been told the car needs a new head gasket. The car has been using water but there was no emulsion on the oil filler cap so I was not expecting this news. My mechanic says if I buy the bits required he will fit them. He is not an expert so ......

So, how does he know it''s an HGF problem if he is not an expert ? Has he done a sniffer test ? I'm hoping when you say "using water" you actually mean coolant ? The blue/green glycol a/f rather than the nasty pink OAT stuff

Saltire (Jonathan) recently had HGF problems. Have a read here....viewtopic.php?f=80&t=27928&start=100

[johnj]

Sorry when I say my mechanic not an expert I mean on Lotus or Elans. I have used him for many years on family cars. He pressure tested the water system and when the engine was switched on the pressure in the system went up suggesting that the the engine was adding pressure to the system via a failed cylinder head gasket.

[Rambo]

Sorry for misinterpreting your post. I hope the link above is helpful to you as background info ?

[robertverhey]

Ok sounds fair, but to verify, suggest do the coolant pressure test with the engine off. The coolant should come out of the spark plug hole of the offending combustion chamber. Will also help to identify the approx location of the leak. That spark plug should look remarkably clean.

[johnj]

I watched the video, seem like a terrible job. I could not see a list of parts he used although I noted he used SJ Sportscars.

[dapinky]

John,

As the head is coming off anyway, I would suggest that it would be a good time to change the cambelt and waterpump whilst you're there....... I would normally suggest that you also do the cambelt tensioner and idler at that time, unless you know for a fact (ie, you've done it yourself, or you have a recept for them) that they have been changed since the car left the factory. Whilst they are not considered to be a 'service' item as such, they are cheap enough to fit whilst it's all apart, and far better than having them go wrong (unlikely, admittedly!) after it goes back together.

Okay, as far as parts go, I would be looking at buying most of the 'hardware' stuff from Rock Autos in USA........ BUT....... the actual head gasket needs to be from Lotus, as it is slightly different to the aftermarket ones which are for the Isuzu application, and have slightly different waterways. They look the same at first glance, but if you lay them on top of each other you can see the difference.... and if you fit the wrong one, it will lead to an early failure (One I fitted to my first Elan lasted about 6000 miles.... replaced with a proper Lotus one, and still working well).

RA 2020.png

This is a copy of what I fitted when I changed the belts, tensioners and waterpump last time I did it.

To that list I'd also add:-

Head gasket (SJ sportscars) - part number A100E6104S

Camshaft seals x 2 (Rock Auto)... either buy them seperately, or replace the DAYCO kit on my receipt with item number 95169K1S which includes the seals for an extra £2
Inlet manifold gasket (BECK/ARNLEY 0374753)
Exhaust manifold gasket (ROL GASKETS MS4206)

The thing to watch for with Rockauto is the shipping....... they have numerous warehouses, so not everything ships from the same location, and you could end up with 2 or 3 parcels, all attracting a delivery charge....... it is often worth spending a couple of quid on a more expensive make of item (for example, waterpump) to get it from the same warehouse and overall save money.

The list I made above will come from 2 warehouses, but even with the additional shipping, it still beats UK prices (manifold gaskets are about a quid each in USA, and a tenner over here!).

Oh, and choose a postal method that includes VAT paid with the order.... that will save a week in customs handling in the UK, for which the marvelous C&E people will want to charge you £30 or so!!!!!

If you look in the Wiki you will find the current 5% discount code for RA, which you enter in the "where did you hear about us" box

There *may* be other items you need to get, but that is what I can think of off hand.

[johnj]

Thanks very much Dave.

I assume this list works for an S2.

[dapinky]

Yep. Any turbo car......

..... the only thing being if you have A/C - then you'll need a different PAS belt as it is longer to go round the compressor pulley.

[johnj]

Hi Dave

I have ordered the parts you listed from RockAuto. I must say without your list I would not have found the items so thanks for saving me some money . Just the labour to pay now

Thanks

John

[johnj]

Do I need new cylinder head bolts?

[Rambo]

Thanks, Dave; that’s exactly the kind of thing I was looking for and really helpful. Can you remember if you changed your head bolts, or did you reuse the old ones?

I've always re-used them (but checked that they aren't damaged!) - they are not a 'stretch' bolt on these engines, so if they are in good nick, there's ne need to change them.

I think i have done 4 or 5 elans now (but none recently!) and don't remember any great difficulties as long as you are careful with protecting the bodywork and checking that everything is detached before pulling the head upwards.

Possibly saved you more money

[Brit-Car-Nut]

Do I need new cylinder head bolts?

No need for head bolts unless one gets buggered. Also, no need for valve cover bolts as they will last a long time.

Remind the shop that the head gasket is unique to the M100 and the turbo gasket is different than any other Isuzu engine except the Turbo impulse and I-Mark.

It MUST be the part from Isuzu specifically for the turbo engine. Lotus has them available via any of their dealers under part number A100E6104S (£40.04 + VAT & postage) and so does SJSportscars and SW Lotus, etc.

Others have tried to save a bit by using the "generic" head gaskets listed by most parts suppliers. The other gaskets from a generic head set will work fine, just NOT the head gasket.

[dapinky]

Do I need new cylinder head bolts?

You are not going to remove the head to do the belts, so no need for head bolts as well as no need for valve cover bolts as they will last a long time.

The OP was asking about a full HG replacement John - hence the "full" shopping list, not the "short" one.

[Brit-Car-Nut]

Do I need new cylinder head bolts?

You are not going to remove the head to do the belts, so no need for head bolts as well as no need for valve cover bolts as they will last a long time.

The OP was asking about a full HG replacement John - hence the "full" shopping list, not the "short" one.

I figured it out and was correcting my post as you were typing. I would buy a "generic" gasket set (eBay or similar) AND a FACTORY head gasket to save money on the other gaskets and seals.

[Simon_P]

I'm going to offer a different point of view on the head gasket.
Dapinky I recall a very long time ago that kmckmc had some head gaskets made, and there was a very long thread I believe that it was either his or the N/A gasket that had different oilways or are you able to say which ones are different? I know also that the 60s elan twincam HG has different cooling holes for different flow to the Ford one.

I've got a set of gaskets somewhere so can check if needed.

The Turbo HG has an extra tag on the end to distinguish it from the N/A

John are you saying that Isuzu have a separate part specifically for the Elan?

Neither Lotus or Isuzu make the gaskets so as long as it is the same material from a known brand it should be OK.

[Brit-Car-Nut]

No, Isuzu only shows two different gaskets: the NA version and the Turbo version. I believe the Turbo gasket I got from Lotus is either in an Isuzu bag or has Isuzu on it, but i will have to look again.

The only place I know to get the correct Turbo gasket is from Lotus who gets them from Isuzu. Isuzu is basically no longer selling Impulse parts unless they are left over stock or still used on current trucks (at least in the US). They used to be the only place to get a Cam Angle Sensor, but that stock disappeared many years ago.

The NA engine & gasket is used in multiple cars like the Isuzu Impulse, I-Mark, Stylus, and Geo-Storm 1.6L.

The water pass thru holes are different shapes and I think some have different "crush rings" or thicker areas to help with sealing. The gasket material is also different between the versions.

From what I read a long time ago, the coolant holes are a different shape and that is where the non-Turbo gasket failed

Weren't the gaskets that kmckmc had made multi-layer?

This is kind of like what happened with the MG head gaskets. They started out as copper based and then MG had them made from a fabric which got other companies to try to make cheaper ones but only the original head gaskets were known to last very long. I rebuilt well over 100 1.8l MGB engines and tried the "cheap" gaskets on my own engines and they all failed. MG also had a multi-layer gasket available for people that were racing their cars and they had a lot better water passages and had crush rings for every opening.

[dapinky]

Simon,

Johns explanation is pretty much as I've experienced with the Lotus ones......

.... when they did the first (big) aftersales sell-off in Bristol I bought up their entire stock of NA gaskets (all 9 of them!) as they were only £2 each..... as they never sold any, so wanted them offloaded.

At that point I had recently changed my own HG, using an aftermarket part from a very early group buy. I didn't even check that the gasket was identical to what came off, as it looked the same to me - and no-one really knew any better.

It worked fine for 6 - 12 months, then went again (just before an MOT, so it needed doing to pass emmissions)..... so I just swapped the whole engine.

I then purchased a 'proper' Lotus turbo HG (once they became available again). in fact I got 2. When checking them all next to each other, and on top of each other, etc it became obvious that they were all pretty much identical, except for the waterways. On the NA gasket (and thus the aftermarket one) they were round, but on the Turbo one they were keyhole shaped to allow better (different?) waterflow.

I didn't really compare the material, but they appeared to be identical in every other way.

Clearly, the aftermarket ones were made from an Isuzu pattern, and were suited to the Isuzu N/A (and possibly even their turbo) engines, but couldn't cope with the slightly higher stresses of the slightly modified Lotus units.

Anyway, I passed on the NA gaskets to various people once it was established that they couldn't be modified to work reliably for the Turbo unit (but would do the job in a pinch).

I'm not sure if Michael ever got a production run of the Multilayer metal gaskets, but i do remeber the discussion..... it was at the time that Lotus couldn't provide OE HGs, so there were few options - but fortunately, they had a new batch made so as the price was reasonable, everything else was set aside.

Bottom line is that if you are only tootling along the roads, then an NA gasket (or aftermarket one) will work fine for a limited time (or maybe even a long time!), but at the time I was doing quite a few trackdays, and it just wouldn't cope with what I was throwing at it.

[Simon_P]

OK so the difference is between the N/A and Turbo, the Turbo one having a Tag so you can tell the difference.

John, yes I get the material diffence particularly with different metals / expansion rates, that's quite a common failure mode when the cheaper material can't handle the difference in expansion - ours are made from the graphite material that I can't remember the name of.