Jump to content
Do Not Sell My Personal Information

Mk1 Fun


Recommended Posts

Hi folks - new guy to the forum, and i would like some advice about an Mk1 I'm working on which belongs to a good friend.

Firstly he got the car with a blown head gasket.He and his mate stripped off the head and bought it too me, but in the process threw all of the nuts/bolts/shims/buckets/injectors, and just about everything else into a box, and I had the nightmare job of sorting it all out :).

So far I've stripped the head down to nothing, cleaned and de-coked everything, had it skimmed, lapped the valves, and refitted them along with new valve stem oil seals.Everything so far seems to be in excellent condition, with no undue wear I can find anywhere.

I have attributed the blown gasket to 2 things.

1. Nothing but water in the cooling system

2. Two blocked waterways, in the form of small drillholes that pass between the exhaust valves of a pair of cylinders.

My Question is: Is this a fair assumtion?

Next I've rebuilt the head and tried my best to sort the valve clearances.Can someone advise me on the acceptable tolerances for the valves please, as I can't get them any closer than this:

Inlet: smallest gap 0.18mm biggest 0.20mm

Exhaust: smallest gap 0.23 biggest 0.28 (except one which is way over at 0.35

Will the 0.02 undersize gap of the inlet valve cause me any problems?

Where can I buy shims and how much do they cost?(I'm assuming genuine Toyota shims cost a mint coz everything else does e.g. gasket set £100)Can anyone help me with a 2.96 shim??

The injectors have a rubber seal on the squirty end with a step in it.The ones we have are quite hard and obviously past it. I want to replace them.Any ideas on cost etc for these?

The rear arches on the car are a bit tatty and we want to fit new ones.The guy at the panel shop said you can't buy MR2 arches but the ones off either an Astra or a Fiesta fit, but he couldn't remember which it was.Can someone help me with this please?

thank you for any advice.


Link to comment
Share on other sites


wow that's a handful you got there but sounds like it's under control....

The tech aspect of your query I'm not going to be that handy until saundy evening as I'll pick up my little magic book with all the mk1 figures which is currently at a freinds place, I'll be able to give you all the tolerances your after, if there are any more you need just add them to the thread :D

Your assumption sounds about right, what sort of age condition was the aw11 in ?

Shims, injectors etc you should be able to get from Toyota Celica Breakers. They're a celica, MR2 and Supra breakers specialist down in Devon, I don't have the number to hand but it's very easy to find using Google, they're a really helpful bunch of guys and generally know they're stuff, if they can't help post on here and I'll try find some other sources for you.

Rear arches can be bought but they're not cheap, if I recall correctly about £120 a side, I hope your good at welding as unfortunately the reasr aren't bolt on....

As I say I'll have my magic AW11 (mk1) book by Sunday so should be able to answer any queries then, unfortunately not by a computer with the book until then...

Out of curiosity where in the coutnry are you ?

All the best


Link to comment
Share on other sites

I believe the clearance should be 0.25 for both intake and exhaust, but best to wait for Ryan to confirm. Yeah you buy the shims from toyota, but i dont think the price is astronomical. Of course it can be expensive if you have to buy all 16! But best just to keep trying to swap them aroud, get as many close as possible, then just work out what sizes you need to complete the job. If intake is meant to be .2 i wouldnt have thought it would cause a problem, but just buy a few new shims for peace of mind.

HG's go for many reasons, usually when they get old they just get worn, or from overheating. As long as the head and block are fine, i wouldnt worry about why it went. Unless of course it has a cooling problem which you would want to sort pronto once rebuilt.

Arche are £80 each for pattern ones. Look here http://www.mr2mk1club.com/panels.html

Hope this helps;


Link to comment
Share on other sites

Hi Ryan and Harvey.

Thanks for the advice guys.

I have a Haynes manual for the U.S. model - not great but it shows the clearances as .20mm inlat and .25mm exhaust.

Here is my shim chart that I had to make to save from going crazy trying to sort placings, complete with greasy fingerprints, I think the tightest gap I have is .02mm too small.


and here is a piccy of the head itself, with the blocked holes marked in red in the overlay pic


The guy at the body panels shop was adamant that loads of folk used arches off another car (astra or fiesta he said).Has nobody here heard of this?He did say that he couldn't get pattern arches for it but now I've seen your link I'll point my mate at it and see what he says.Don't think he'll be chuffed with the prices though, he's still reeling from buying the £100 topset.

Ryan the car itself is in fair condition, although I've only seen it very quickly the once.Apparently the interior is in good nick, and it has a brand new exhaust, the electrics work fine all over.There's a small mark on the bonnet where it looks like someone has caught it on the wiper he said??I think the arches are about the worst part of the bodywork.Best of all it was given to him free, and he is making it fot for his wife to drive, as their second car.He has a mountain of paperwork and receipts including every MOT it ever had.

It is missing 2 rather important items - the offside mirror and the front bumper.The mirror is gone but the bumper was fine until the guy who towed him tied the rope to it then that was gone too, so if anybody hears of one let me know please, We are in Kent near the Dartford Crossing.



Link to comment
Share on other sites

It could also be something like under torqued bolts.... u can never tell what the previous owner has done just to get the thing running. Ive herd u can use Yammah bike shims on my engine... as yours is the son of mine.... they might have kept things similar dont know, but might be worth looking into. If u cant get hold of shims at the mo, or cant afford it, and need the car on the road A.S.A.P it wont do to much harm running the old ones until u find a set. It'll mean it will run a bit noisey but what the heck... from your discription (only briefly read because still at work) they arnt that far out. What are the buckets like... seeing as the order is all mest up, it prob wont harm changing the combinations until you get a closer match??? Just food for thought.

Link to comment
Share on other sites

Hi Scot.

There is a receipt for garage work for - you guessed it - a blown head gasket.About 2000 miles ago.The guys said that the bolts weren't particularily tight.

Most of the valves are gapped to within 1 thou +/- .02mm so I'm not expecting it to be too noisy.I did look at swapping out the buckets but decided against it because the micrometer I was using had a bigger shaft than the top of the valve stems so I couldn't record the thicknesses, and I'm blowed if I'm going to do it trial-and-error, I'd end up going insane.

Question:Can I expect the valve clearances to remain the same once the head is torqued down?I've gapped all the valves on the bench.

Just got news we have found a complete front bumper for £20 but not the mirror, which is a nearside, not an offside we need.In fact the guy with the bumper has a complete MK1 he is breaking, but I haven't any details yet.


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...