2 cylinder Suprex - warning sign?

[Thrumbleux]

Coolant pipes relative to hand brake rack auto adjuster mechanism: Flow to radiator and to heater matrix runs on left and return from radiator on the right. Can only be fitted one way but I am sure someone has managed to get this screwed up in the past.

The heater hose runs close to the handbrake mechanism - just checking in case I'd displaced it. Evidently not, and the bit of protection I added will ensue it doesn't get rubbed through.

When raising subframe in stages, you should guide the rack into hand brake lever from inside the car. Use a long flat bladed screw driver.

Or a pair of long nose pliers in my case as raising into its receptacle was what was required.

[Thrumbleux]

It drives! And drives well. Only glitch was the drivers door handle losing its connection to the latch. Which may be down to a fit of pique on Thursday when I finally ran out of patience with the handbrake and slammed the door very hard. Not like me to break things in temper as I learned long ago that I only end up having to repair whatever is broken, And so I am reminded of that again! Cable broken or dislocated after the slam?

Anyway, the driving part is fine. Engine pulls well, no leaks, overheating etc, and the gears and clutch are as they should be.Even the EML has extinguished. Plan is to run a couple of hundred miles on the relatively low grade oil that's in it for run-in purposes then change it out for my preferred oil along with the filter and send a sample of the removed oil for analysis. Which will show all the wear metals which will tell me the rings have bedded in as expected.

Off to FQ101 to research broken door handle cables....

[Thrumbleux]

Some photos taken as I went about the rebuild.



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Pistons as they were removed and one cleaned and one ready for ringing.


IMG_4107.JPG Crank journal and crankcase after previous sealant removed and a quick wash down with petrol.

IMG_4092.JPG Improvised valve compressor.

The point here is that there is a bolt hole near enough every valve to enable an ad hoc fulcrum.
IMG_4112.JPG Fully dressed but for the TIK and exhaust. All that remains electrically to be connected in the car is the battery/starter/alternator cable, two plugs to the ECU (connect prior to fitting TIK to airbox) and a connector that sits atop the subframe. Simple - no?

[Thrumbleux]

Some photos taken as I went about the rebuild.



One piston cleaned and ready for ringing.


Crank journal and crankcase after previous sealant removed and a quick wash down with petrol.

Improvised valve compressor.

The point here is that there is a bolt hole near enough every valve to enable an ad hoc fulcrum.
Fully dressed but for the TIK and exhaust. All that remains electrically to be connected in the car is the battery/starter/alternator cable, two plugs to the ECU (connect prior to fitting TIK to airbox) and a connector that sits atop the subframe. Simple - no?

[Thrumbleux]

IMG_4085.JPG Cause of all the grief.

IMG_4077.JPG Sat like this for a month.

[tolsen]

Nice photos but the "cause of the all grief" photo needs further clarification. I can see two piston crowns and a burnt valve but what are the other two bits not if focus? Big ends?

[Thrumbleux]

Yes, out of focus is big ends - just happened to be included when I shot the valve. Not a great photo of the valve but pretty much all of its seat is destroyed.

[tolsen]

Were oil scraper rings stuck or had they lost their springiness?

[Thrumbleux]

They weren't particularly difficult to extract though they had a sort of stuck there feel. They didn't spring out when freed so I guess they lost their temper.
Just had another look at them and the plain rings have a build up of carbon on the inward facing sides in the pattern of the central ring and the outer sides are shiny where they have been in contact with the piston with a very narrow dark band where they must have been protruding. The central ring has some carbon and absolutely zero springiness. They also have a very long engagement tongue wire. On the new rings that wire wasn't much longer than an inch. So design has changed over the years.
Do you suppose the oil control rings become overheated (no discolouration though) causing the loss of temper and carbonisation? The only other carbon found was in the wavy passage and ducts in the exhaust manifold that serves the aux air system but given it had been using oil at a rate of 2% of fuel for quite a while that was to be expected. The pistons cleaned up after a soaking in cleaner with nothing more vigorous than a scuff with a soft nail brush. The rest of the engine's internals were very clean - as can be seen in the head and crank journal shots.

[Thrumbleux]

IMG_4086.JPG

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Compared to how 'lively' the new compression rings were, these are pretty lifeless.

[tolsen]

I think they were too low on oil ring tension. Too high ring tension means high friction, increased wear and reduced power. Too low tension results in the problems these engines suffer.

Question: Did you measure ring gaps and were they within spec?

[Thrumbleux]

No I didn't. I thought about it but a combination of lack of time and sub zero temps killed the idea. I figured I was getting parts from the OEM and there was no catastrophic wear or damage elsewhere so just slotting it back together was acceptable. I never intended blueprinting it. The shells were the only things I measured and then only relative to new.

[Buckster]

You did a great job, this will be a good reference thread.

[Thrumbleux]

Cheers.
There will be a few things in it that may be of help to anyone attempting the same.And a couple of things that as far as I know hadn't been done before (eg, rear wiring harness removal and replacing all mains shells with crank still in place).

Car did 130 miles yesterday - first proper run - and all OK with the drivetrain. Door handle also fixed (I have a simple cheap fix now for when the cable breaks at the handle end) but handbrake may need attention - ho hum....

[Thrumbleux]

Must have done a half decent job then. MOT today and HC was at 6ppm (200 permitted) and CO at 0.001 (0.200 permitted). And oil analysis (at 1000 miles) read level of all wear metals was compatible with run-in procedure. A far cry from adding 0.5l of engine oil every 250-300 miles...