998 Turbo Build - Slow Progress
Turbo Mini Forums

AA man is on the way, as none of the garages locally were willing to come out to do it. Here's a quick vid of it running badly, you can hear it struggle and pop.

In the mean time I fitted the shiny new stainless fuel lines.

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Just managed to do a proper compression test on the car, got:
180
200
200
200

Then filled the rocker cover up with oil, so the guides were submerged, and did another, and got exactly the same results. This suggests its not the guides burning the oil doesn't it?

and it's now running on only 2 cylinders, pulling the plugs on 4 and 2 didn't have any effect.

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

For the oil test you are supposed to put oil down the spark plug hole into the bore, and any difference will be due to the oil sealing the piston rings. I'm not sure how filling the rocker cover with oil affect results but those look like good compression figures anyway.

the oil in the rocker cover was supposed to test the valve guides, if they were letting oil in the value would go up.

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

I don't think that test is going to work as the pressure in the cylinder will only increase when the valves are closed, you should also watch closely how the cylinder builds its pressure you want it to pump the gauge up swiftly in as few engine revolutions as possible as this shows efficient sealing of the rings and valves, a leak down test is a better diagnostic test as you can usually pin point if and where a leak is coming from

Speeding is like masturbating, everyone does it, but not all of us film it and put it on the internet

[quote=fab,8th Oct, 2010]fuck off

Got the head off today, doesn't look good...







Bores look worn again, is this bore was from running rich?


I also spun the engine over on the starter for a bit after wiping the bores and pistons down, and a coating of oil appeared on the piston.



So is it back to square one? or is this normal/salvageable?

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has it been over bored ?
I recall reading there could be an issue on SBU and you can happen to have to sleeve an oil feed (it's in the yellow bible somewhere)

Rusty by nature

It hasn't no. Whats an SBU?

The head is currently on the way to Benross HQ, to be checked out, the valve guides were lifting. While it's there if I've got the funds I'll ask him to work his magic on it.

The car is also coming off the road, bought a replacement run around today, so shouldn't have as many problems with needing it fixed to get around.

New car is a 1.6 mx-5

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Got a chance to pull the first (ebay special) engine apart today, got the pistons out, big ends look quite worn:


And the journals on the crank have gone


With the pistons out i set up the DTI gauge to check the endfloat, came out at 0.165mm, which I make to be 6.5 thou. the thrust washers are in a bad state which is probably the cause of this..



Then took the crank out and the mains look like this:


Not great for a supposedly rebuilt engine, but then serves me right for buying blind off ebay...

finally, OT but it's been perfect weather for the new car. Had to listen to all the 'hairdresser's car' jokes but it's bloody quick compared to the mini..

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

I used to have a mx5 was a cracking little car!

998 t2 ongoing project.

Those shells don't look that bad to me. Maybe just the way im looking at them though as the crank doesn't look perfect.

What are the piston rings like?

Is that a eunos MX5? Looks like an early one.

Yeah, the shells look a little scored, there's straight lines along most of them, though they don't look too bad. It's the thrusts that look knackered. They'll all be replaced anyway as the crank needs a regrind.

It is, it's a 1990 eunos roadster import. Bought an import because unlike the British ones there's no rust anywhere on it.

The piston rings themselves were okay, it's the cylinder walls that are the problem, there's corrosion spots in two of them and a long gouge in one as well. Need to get it to a machine shop to make sure it's not too deep that it's scrap.

Edited by Mike-998 on 26th Apr, 2013.

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

A little more progress with the build. Got the cylinder head back from Benross, and what a job! looks fantastic.

Spoke to the guy who built the engine and he is adamant that the smoke was a cylinder head issue, so I'm in the process of sticking the new head on and hoping for the best. I'm not too optimistic though, and am contemplating sending my spare 998 block and some calver ST oversize pistons off for machining.

Couldn't get the engine running though, as we found even with the rockers adjusted fully out there still wasn't any clearance between them and the valves, so some pedestal spacers have been bought and will be fitted in the near future.

Some pictures of the new head:


And some very blurry port photos



Spec is:
-fully ported, polished etc
-combustion chambers alterd 28cc in them
-head skimmed to clean up 0.004"
-diffrent caps and collets 3 groved type
-new manganize guides viton stem seals
-fast road race springs thin wire doubles hastrloyd innner spring retainers
-3 angled seats inlets
-stellite hardend exhaust unleaded seats
-new stainless race valves sizes 26mm ex and 33 inlets

Chuffed with the result!

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Well I haven't been able to get to the car until today, and with MITP and a slot on the TM stand I thought i should probably get cracking.

Started out by fixing the results of my incompetency:





No major issues there, just a lesson learnt!

Then took the car for a spin, and after it had warmed up it started to smoke again, with a nice blue hue. Seems to be only on acceleration?

Current state of engine is:
Professionally (?) rebuilt short engine, gearbox etc
Benross Head
NA
Breathers venting straight to atmosphere (one on tappet cover, one on transfer housing, and looks like its breathing out the oil filler as well)



So, with the new head it seems the only cause of the smoke is the rings. So after I had reached that disappointing conclusion decided that the spare engine I had lying around (as you do) could go in.
Its a std 1.3 with the only modification being a central oil pickup. Freshly rebuilt with new rings, bearings, followers, etc etc...


Plan is then:
1. Remove smokey 998
2. Fit home built 1275
3. Hope it works (if not, go to step 4)
4. Hope I can fix it by MITP

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

What happened to your wheel? Nuts not tight?

Yep, on the first run with the new head and brakes on, the wheel nuts weren't done up. 20 yards down the road i see the wheel jumping into the ditch at the side of the road..

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Unlucky mike. Still the car seems to be making progress.

BHP sells engines, but Torque wins races!

Thanks, its just frustrating having a box full of everything needed to turbo the car, but not an engine that works. I'll just chuck it on this 1.3 if it works i think

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

A late night tonight, but reasonably successful. 998 engine has been removed, taking far longer than necessary because of the bloody roll pin that connects the shifter to the back of the 'box...

Plugs look oily..


Still shiney cylinder head, will be going on the 1.3 as it's the only known good head I have.


Oily Bores and pistons, engine had been standing overnight before the head was removed


Poor photo of an exhaust port


Car as it stood around lunch time


And the car at 10 this evening



Just got to put the minispares diff into the new engine, along with a duplex chain and gears, so that all the turbo stuff can be put on this engine. Hopefully things will progress faster tomorrow.

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Well today went much smoother.

4 Pin diff in


Engine in car


Sticking the bits on...


All together (save a starter motor, so we couldn't actually see if it works..


All I need to do now is make sure it works, MOT and tax it. Managable in two days yeah..?

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

So turns out you cant put a 998 head on a 1275..




a tiny amount of the waterway in the 998 head overlaps the fire rings, causing this when I filled it up with water.

Took the head off again, wiped everything down, drained and replaced the oil, put a large bore head I had sitting around back on and chucked it back together.

Turned the key and it started and ran! First engine build that i'd done everything so pretty chuffed. Only a slight issue with the clutch not returning correctly. Its a verto clutch and when the pedal is pushed down and released quickly the slave doesn't return with the pedal, it eases back in slowly. I don't know what could be causing this but might try a new slave and see if that helps.

Don't think it will make MITP unfortunately as there are too many problems with it for it to get through an MOT today. :(

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Check the slave and associated pipe work.

I though you had a 12G940 on your 998 :/

In the 13's at last!.. Just

Ahh there's a kink in the pipe to the slave, as it came off a pre verto engine, that'll be restricting the fluid returning to the master cylinder.

And nope, it's a benross modified 12G295. Luckily I heard the water running down the exhaust before I started it up, could have been a lot worse..

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Some more progress, got the 1275 engine I built running great, chuffed

Car's not going to make it through an MOT as is however so i'll probably get it trailered up to my new home in Coventry (lovely place by the way..) so I can sort out the odd issue.


The new job in Coventry is proving handy for car work though, it's a company that rebuild aircraft engines. I'm running the engine test rig but have still done all the training for the machinery :)


Took the opportunity to use their glass blaster to clean up the conrods and the old 998 pistons, and separate them ready for payday and some of these:

http://www.calverst.com/newshop/index.php?...&products_id=81

Should also be able to use their boring an honing machine etc, so will save quite a lot of money on maching costs on the turbo engine (which is finally in the process of being built). Now living on a salary rather than a student living it should be much quicker as well.

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Any updates?