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Turbo Engine Rebuild

scam75

Active member
Afternoon chaps

After posting various bits and bobs on various threads, thought this deserved it's own thread. Long story short when the head came off as HG had let go (cyls 2 and 4), there was a horror story in cylinder 3, bad scoring on about 1/3 of the bore. There is also light scoring in bore 2, this was evident at last HG change 60k miles ago, but this had not got worse. So as I write this the short motor is with AMAC engineering for a full rebuild, and they also have the head for skimming.

We are getting Westwood iron liners fitted, and are using a set of Wossner forged pistons, type that are coated for iron liners and not alusil (K9531DA pistons). AMAC have done a few of these and know their onions. For what it's worth the horror Wossner stories banding about are with alusil bores and the alusil compatible coated pistons they do. Iron liners would be much less susceptible to damage anyway but fairly happy after all my discussions and research that this is the way to go and have full trust in AMAC.

So in addition to that, AMAC will check, polish and balance the crank, fabricate a pick up pipe strengthener, new mains and big ends, all gaskets and seals done. Basically a complete strip down and rebuild of short motor with all parts cleaned, inspected and replaced if need be. They will also source the correct thickness of Cometic gasket once the work is done.

Once that is all done we will get the valves reground with new stem seals and the head cleaned up before re-assembly. I will fit a new water pump, thermostat, plugs etc as a matter of course. The other issue is that some wiring and sensors that have been brittle have given up the ghost when the engine came out. So we will slowly attend to all these matters when putting it all back together.

It's been a fairly long journey so far, as my mate who is removing/reinstalling engine is just doing bits and bobs when he can. AMAC tell me one month for them to be done, expect that to at least double!! Then probably looking at further month for reassembly back up here. I'd imagine very tail end of the year before she turns a wheel again and I will get the bonus of running her in with snow and ice everywhere!!

Anyway, could have been doing without this but needs must and I should have a nice strong, fresh engine to show for my efforts. Cost is currently looking about £5k - £6k in total barring any further issues.

Currently debating the clutch. Was replaced 60k miles ago and I've not given it a hard time. Would like to avoid buying a new one as bank balance already on it's knees!! Just a thought, could the friction plate alone be done if need be? Haven't looked into this at all yet? I've asked my mate for a condition report...........

I will update when anything develops.

Cheers

Stuart
 
Obviously you have to stop somewhere, but I'd have the rod small end bushes and the valve guides checked, while you're in there. And probably the rods checked for straightness too. Shouldn't cost too much extra.
 
blade7 said:
Obviously you have to stop somewhere, but I'd have the rod small end bushes and the valve guides checked, while you're in there. And probably the rods checked for straightness too. Shouldn't cost too much extra.
AMAC will be checking the rods for size and correcting anything they find and honing if need be. Essentially the short motor will be completely disassembled and anything found wanting will be dealt with.

Valve guides were new at last rebuild but will be checked.

Cheers

Stuart
 
I agree with Paul.. there will most certainly be wear on both the rod wrist pin bushes and also the valve guides.... IIRC those wrist pin bushes are only brass, I'd have expected bronze but mine looked like brass and no.2 is very much prone to failure... I would change these as a matter of course, they will be oval, not round by now.

Pete
 
Thanks Pete. I see I have a main bearing set and a big end bearing set in my quote, rod wrist pins separate from that?

Cheers

Stuart
 
Yes...they are only bushes...very cheap, material cost is very little, you could turn your own on a lathe but you need the jig to check the throw is spot on.. when I rebuilt my engine the bushes were no longer round...this is normal for an engine with a fair few miles on it.

Pete
 
PSH said:
Yes...they are only bushes...very cheap, material cost is very little, you could turn your own on a lathe but you need the jig to check the throw is spot on.. when I rebuilt my engine the bushes were no longer round...this is normal for an engine with a fair few miles on it.

Pete
Would you assume a competent machine shop would do this then as part of a full short motor rebuild then?

Stuart
 
You would hope so but best to check.. they weren't mentioned by Serdi when they rebored my block...I had to take the rods back after checking them myself... I can't recall how much the extra work cost but it wasn't much and IIRC was done within a few days.
 
Hi stuart
hope you are well. Sounds like you are in A similar position to me. My crank has play so rebuilding but I’m fitting 3.0 crank and doing a 2.8. Pure performance motorsport in oz have forged rods on offer just now so picked up some of them and then running some JE pistons which lindsey Are ordering and then getting block bored to 100.5 and re alusiled.


I had bought a new Sachs pressure plate and cup clutch plate which seems to get lots of good feedback but with it now being 2.8 think I will need to get a kep plate. Might sell the new Sachs one of its if interest
cheers
Sandy

 
Hi Sandy

Long time no hear. I am good thanks, well except my bank account lol, hope you are well too!

PM me with details for pressure plate and clutch plate.

Cheers

Stuart
 
I am in the process of rebuilding an '86 Turbo engine. What's the best source for a complete (as possible) engine rebuild kit?
 
ktel said:
I am in the process of rebuilding an '86 Turbo engine. What's the best source for a complete (as possible) engine rebuild kit?
Hi. I have not come across a "complete" engine rebuild kit. I suppose the question is how far does your rebuild go, and then just need to source what bits you need and what jobs you need done as you go along? That's certainly what I've done.

Stuart
 
Hi ktel

It's difficult to make a list without first knowing the condition of your engine. At the very least you'll need a full gasket set, Victor Reinz is your best bet and IIRC the kit will have all the gaskets required. If the bores are scored you'll need a specialist to rebore them ( don't trust the work to anyone not familiar with the engine) and need the larger pistons/rings to match. You don't say where you are but if near London talk to Serdi UK in Uxbridge.

Pete
 
Thanks for answering! I am in Athens, Greece, not even close to the UK. My engine is in a pretty bad shape. Had been in a car kept outside for a couple of years. So I think that pretty much everything needs to be changed.




 
Looks a little sad, however depending what the condition of the oil is inside it may not be as bad as it looks - on the other hand if water has got in it may well be worse!
 
Well was down at the garage the other day finalising a pre engine arrival parts list. It was also time to check the turbo and the clutch out. Turbo is sweet as a nut thankfully, rebuilt 60k miles ago and very much still good to go. Clutch on the other hand, about 70k miles old, needs replacing. Friction plate not much life left, bearing grumbly and pressure plate showing signs of wear but probably would have been OK.

So with some help from our Sandy, I have secured a OEM release bearing for £60, a new pressure plate for £125 and got a cup friction plate from the states for £160. Its costing $77 for my US cousin to post, he has stated it is a gift so depending on the mood of the customs man I may or may not need to pay import tax. See how we get on. But £345 all in for an uprated clutch will do me just fine!

Spoke to AMAC. They will be replacing the rod wrist pin bushes while they are in. I'm also getting them to check the guides in the head and replace if need be. They were replaced 60k miles ago.

So with all that taken care of its a waiting game now for parts to arrive and the short motor and head to come back all shiny.

AMAC says 4 weeks, so we are already a couple of weeks past the original 4 week time frame!! Anyway no rush and gives plenty time for parts to make their way to me.

Stuart


 
Not much in the way of updates for the time being. No updates from AMAC, probably call them this week for an update.

Clutch release bearing arrived as did cup friction disc from the states. Managed to avoid any import duty on the disc as my cousin described it as an "auto accessory gift", so was nice to not have to pay the customs man for a change!! So with this added bonus a full new clutch kit, with uprated disc, OEM pressure plate and OEM bearing, has come in at £400 including the delivery costs. Got to be pleased with that.

Stuart
 
Hi Stuart...

That sounds a good result, don't forget to replace the needle bearings in the clutch fork, check the pin for wear too. Mine was badly worn from the needles, god knows why Porsche didn't use harder material for the pin? If you have a lathe and a little machining experience the pin is a simple thing to turn up. I made a new one from EN8 steel, much tougher than what I assume was just mild steel of the original.

Here's to your car back on the road soon..

Pete
 

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