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Hi all, so I have blown the head gasket, coolant in #4, and exhaust gas and oil in coolant. Now, I am sure the big MX5 garage at North Brissie that everyone knows will do an awesome job, I just can't come at the quoted labour cost of removing and refitting the engine (10hrs each way).

So here is my plan, please feel free to critique its logic:
- remove the head myself, trailer the car to the machine shop and get them to inspect and diagnose the head and also inspect the block while its sitting in the car on the trailer.
- If it is just the head that needs work, I just trailer the car back home, wait for them to finish the head, then reinstall it myself at home.
- if the block is involved too, trailer the car home, pull the engine, return it to the machine shop. Pick up the finished long block, and reinstall it at home.

I am pretty confident wrenching on just about anything short of going inside the engine. I can change a timing belt and water pump, for example. I have not done a head gasket before.

So does this plan sound feasible, or am I over reaching?

This next question will reveal my ignorance, but is there a difference between a machine shop and an engine builder? Do some engine builders do their own machining?

And lastly, what are your recommendations for a machine shop / engine rebuilder in the Lismore - Tweed - Brisbane area?
Many thanks.

If you're confident in your ability to remove the long block, then why bother with half measures going to and from and trailing the car? Remove the long block and take to the big MX-5 shop, or another recommended builder for a full assessment and required work.

I agree 10 hours each way seems a little long for an engine removal and install by an experienced mechanic seems a little long, but I've never pulled an engine, so maybe it's accurate? Does that include any rebuilding labour, or just the remove and install? (Pretty sure I recall an engine swap being done at a Sydney dodgy day once, which would put it at under 12 hours total by amateur backyard mechanics)

95% of the time it's a problem only with the head when a head gasket blows. The block is cast iron and rarely gets damaged. That's providing, of course that there's not a blown piston as well, although in your case it doesn't sound like it.

My approach would be to remove the head myself and take that to be tested and repaired if possible. Any reputable engine shop will test the head for hardness, straightness and thickness on the countertop before they accept it for work.

To be honest you'd be pretty lucky to find the head is repairable. The gasket usually blows between 3 and 4 because that's where the cooling is crappiest.
Basically the head gets so overheated in that area that it softens and either warps or presses itself so hard against the head bolts that it squeezes its way around them. Once the head has softened like that then there's no economical way of re-treating it.

Once the head is sent off then you've got time to very carefully scrape the top surface of the block clean and examine it for straightness and bore damage. You really only need a straight edge, some feeler gauges and a sharp eye to determine if anything needs to be done with the block.

ninerwfo wrote:.............And lastly, what are your recommendations for a machine shop / engine rebuilder in the Lismore - Tweed - Brisbane area?
Many thanks.

Ben Simpson, Phoenix automotive services Mechanics & Motor Engineers - 7 Simpson St, Kirra (Coolangatta) QLD 4225
He re-built the Problem Childs engine... theres some pictures of the head in my thread in MX5 garage chat (Daffy's SE)

Thanks for the replies folks. Lachy, that figure was the labour to remove & refit, did not include repair labour.
Daffy, thanks for the tip on Phoenix - have read all of your epic struggles with the problem child, really hoping that I might be able to learn from the bruises of others with this repair! Will certainly give Ben a call.
If anyone else has machinist/builder recommendations for this area it would be much appreciated.

manga_blue wrote:To be honest you'd be pretty lucky to find the head is repairable.

And, if it's an NB8A as per your details, then not easy or cheap to find another NB8A head, so you might want to consider changing over to another 1.8 head, or alternatively just get another [good] 1.8 motor.

Cheers Clubman, forgot to mention it is a forged engine, so if the block is involved, I'd be looking at a rebuild to same spec. That's why I'm after the names of some trustworthy builders. If it's just the head, I'll put it back on. But if it is more than that - then I'll need to find a builder!

Hi mate ring or txt me for details on 0437795084 kim
I just had a head , NB8A done by a guy in M'bah cheers

If you want Bens mobile PM me and tell him Tony told you to contact him ( I'll give him the heads up) he goes above and beyond and does all the work himself. He not only works motors, but also competes in track. He's one of the good guys that wont screw you over!

Hey mate, you find a machine shop yet? If not call Troy at Arundel Cylinder heads at Gold Coast 07 55716952 he knows what's he is doing and doesn't rip you off. He used to do all my machining when I was up there. Tell him Todd from asap told you to call him he will look after you.

Block will be fine, use cometic head gasket and arp head studs when you put it back together, make sure you clean block well! Clean block and head with brake cleaner or thinners before assembly as machine shops spray wd40 or such on head before they wrap them. Also make sure you blow head stud threads in block out before screwing studs in.

Oh and for a so called Mx5 workshop to say 10 hours labour to remove an engine and the same to put back in!!! They are having a laugh! Yer maybe with an apprentice that doesn't know what he is doing! I could and have done a full engine removal, rebuild and refit in 20 hrs. If the car is on a hoist and they are using air tools it should only take 1.5 - 2 max hrs to remove an engine and you usually double it to refit

Many thanks for all the excellent referrals folks, you can't have too many good contacts! Will ring and talk to each one.
Have started to pull things apart, and sure enough, the exhaust ports for cyls 2-4 look like this:
- ... drum roll for #4..
Yep, green water everywhere. A valve closeup of #4
It sure was a wierd experience undoing the sump plug, and seeing green coolant come out fist!