History of a Lola T492 Sports 2000 chassis?

[morninggents]

Maybe a daft question, Graham, but is there any fuel getting in?

[911thillclimber]

It's all there, the carbs have never been an issue, fuel pump works and the bowls are full.
I need to walk up to this problem, check everything all over again and then, if i cant see another way, re-wire.

[S griffin]

It's a pain when you can't work out the problem. Hopefully it's not a major fault and just needs a little tinkering

[VIVA GT]

I'd say to check the basics first. It's always an assumption that if it's a complicated system, it must be a complicated problem, but quite often it turns out not to be the case.
Could t simply be that the crank sensor is too far away from the trigger ring to pick up a signal? (You can often check a crank sensor by passing a metal object such as a screwdriver past it to see if it registers. The ignition has to be switched on obviously).

[911thillclimber]

Spent 4 hours checking everything all over again today.
Everything correct, and the sensor air gap is 35 thou, as instruction manual.

There is a tell-tale light on the unit used for simple fault finding.
There are 5 common faults listed in the diagnostic page, and i have the second one which sights the Crank sensor as the issue. It is new and supplied with the kit inc the bracket to position it etc.

The correct resistance of the sensor is 620 Ohms, mine is 618 so 'good',
There are no sparks at any of the 12 plugs.
All powers/grounds etc are good.

I'm waiting for email replies from the manufacturer (Electromotive Inc) and supplier, (Clewett)
No idea what to do next.

[S griffin]

Thanks for the update. At least you've managed to find out what isn't wrong with the car, so you can have a better idea of what could be wrong. Just hope they email you back in time

[Gerard C]

Originally Posted by morninggents

Maybe a daft question, Graham, but is there any fuel getting in?

NOt daft, just good. The PMO's carbs are inspired from Webers and like many others made in the US, you have a "window" on the side to check if fuel is coming in and have a rough idea of the float bowl level. Graham is right to hunt an electric gremlin imo.

Would it be worse to check the starter speed and change for a more powerful battery?

[911thillclimber]

Much has happened in a last hours. Clewett have firmly stated my wiring installation is the root cause and it has to be changed to fee the crank sensor from noise.
All that work for nothing.
The starter motor is noisy too, so that has to be suppressed.

I just have to bite the bullet and do it.

Rolling Road session now booked for 17 March.
Nothing like a deadline!

The carbs are good, fuel getting in. Turned the engine over by spanner this morning, has it ever got some compression!
Tried the motorsport freshly charged battery and the LiPo batter jumped on yesterday so a lot of power there, made no difference but turned over a bit more eagerly.

Summary:


Everything I have done below has changed nothing from a week ago.
When you switch the power on, the ecu shows solid green light.
When you crank the engine over, the green light stays solid (it should flash red/green/red/green etc
When you stop cranking the engine is shows solid RED.
Disconnect the power and the light sequence repeats.

Clewett says this show the crank sensor signal is not present, and that is due to interference from the leads and coils and starter motor.
Or the sensor is broken.
I have at their request sent pictures of the layout of the coils and the ecu. I am expecting this to be condemned as they have repeatedly stated the sensor cable must be at least 8" from any of those noise sources. Most significant noise source is the starter motor. The stock starter is ok (!) the high torque starters are dirty.

This is what i have done and the result:

All wires are continuous and carry 12v nominal to all places they should.
All wires are in the correct location in the ecu 23 pin plug.
The crank sensor has been used with a 35 thou air gap, and this is now 48 thou max is stated to be 50 thou.in the Clewett manual.
As far as I can tell, the sensor is timed correctly to the toothed wheel as per instructions and as engineered by Clewett.

I have tested the sensor using the Hz setting on my dvm, 1.45 Hz after cranking the engine for 15 seconds.
I will repeat this, but the sensor lead id still close to the plug leads/coil pack remember, 2" clear at best. (not 8"+)

My next sensor test is to remove it and track Hz away from the car. This will answer the frequency count, though the meter could still be the problem.

I have powered the 3 feeds to the ecu and the 2 coil packs with a n independent 12.7 volt battery. Made no difference, BUT cranking drops the volts to 9.7v from 12.5, so ecu and coils do not get 12 volts without the auxiliary battery.

So, with all this done where am I?

I will do the sensor out-of-the-car test. That will take a bit of time, done today using my lathe as a rotation source, easily 1000 rpm.
I am sure the wiring is all correct.
The only outstanding issue is the plug lead/coil pack locations, so this means clearing the engine and re=wire all the plugs again using as many of the cut leads as I can.

The coil pack looms will reach to the gearbox end and reach the ecu with ease, a few wires will need lengthening, trivial in the scale of things.
Before i clear the engine looms I will await Clewetts response to my pictures, but i know what he will say.

finally, to clean the wires to the starter (the thin ones, not the cable) needs a 1.5K ohm resistor in line.
How or rather what do i use for this please?
Is it simply a resistor from (say) RS? soldered and sleeved in-line with the existing cables? Could do with some guidence.

[VIVA GT]

Wow, what a chore. Good luck with this, I hope you find a simple solution.

[Gerard C]

Cant say for sure but very much intrigued by the resitor thing. Did they say why the sensor must be away from starter noise? Can it be an electric interference between the starter itself and the ECU?

[911thillclimber]

Sadly, Clewett say the unit could be faulty and I should consider returning it to the manufacturer for checking, in the USA.
Electromotive say on their web site they are not taking any repairs now..

Thus, i have spent a fortune on something that does not work and cant be replaced and i'm 3000 miles away from them.
The starter is the largest noise maker on engines.

Doubt i will be doing this year's hill climbs.

Utterly gutted, no idea why i bother.

[spd(john)]

Gutted for you sir, I am sure if you drop them a email with a link to this thread, they would gladly sort some thing out for you, after all this race car and your self have generated so much interest over the years it would be negative publicity for there company.
Hope all ends well and you get to try the fruits of yours and Mrs 911 labour.

[911thillclimber]

Hello John! hope you are well!

In fairness, Clewett who sell these dedicated Porsche systems are standing by me.
I need to re-wire the engine, now started and see if that fixes things.
If not the ecu to duff. They will sort it when they get it, but i have told them I will not be paying to return and post back the ecu when it is duff.

I currently have little faith in Electromotive the manufacturer, the person looking into it works 1 day a week.....

Plan B is to cast aside the ecu and replace it with a UK or more common ECU, Emerald comes to mind and claim a refund off Clewett to pay for it.

Next few days are key but for the first time in 31 years I feel i won't be hillclimbing for at least 1/2 the Championship, and that really @isses me off!

[Gerard C]

Dont know if your Plan B is feasible but did you consider a Plan C with something like that: https://www.123ignition.de/123-ignit...bluetooth.aspx

[911thillclimber]

Tried a lot more today, all to no avail.

Plan B warming up (DTA ecu driving the other parts, ignition only.) Calling them tomorrow, only 1 hour away, might try to visit them.

Plan C is evil!
The dist is over £2,000 but you then need all the rest, coils etc.

The DTA option could be £600.

Awaiting Clewett's response to my request for a replacement unit.
But i think I know what that will be.

Customer Service suddenly vanishes when $$$ are involved. might be surprised yet.

[Gerard C]

As you say good point for DTA they are almost at your door. The T2i even features a launch control system which could be useful for hillclimb if you're allowed to use it.

[911thillclimber]

Yes, all those tricks are allowed Gerald.

Real crunch week this week.
While I wait to see what unravels, I can do some normal stuff, wash the cars, but just stand back from it for a few days.

[S griffin]

Hopefully you can put what you know to it to fix the problem. Best of luck, you deserve something after what you've been through with that car

[911thillclimber]

t was a pleasure meeting Chris and Rob today and really appreciate the 5 hours we spent going through everything and more.
Big effort, learnt a lot and have good details to send to Clewett and Electromotive for when the XDi box goes back to America.

We did not get it going.
Positives:
The sensor is good, especially when we reduced the air gap to 10/8 thou, the sinusoidal wave was crisp and 4 volts.
The air gap made a significant difference.

The status of the light is unchanged though twice and briefly it did in fact alternate for maybe 2 or 3 seconds, but then reverted back to 'solid green'.
Rob and Chris could not see anything I'd done was the problem.

Photographs were taken of the traces to send to Electromotive

We have got to the conclusion the XDi is suspect.

Negatives?
Have to pay to ship to USA and back
Loose 4 weeks
Cancel events and rolling road.

[911thillclimber]

Bitter-sweet day on the Lola.
Good bits:
The engine RUNS!
Using the old distributor and system on the top 6 plugs and after freeing off 2 of the 4 carb floats it coughed and spat and farted and burst into life.

Sounds absolutely glorious, the throttle response is out of this world.

I even started it twice to be sure, same result. Both sides of the engine same heat too, so all 6 behaving.

Bad bit:

Mike's lovely 12 plug distributor does not fit in the engine well, the drive gear mesh is too sloppy.
The back lash must be 5 degrees, so the timing would be wondering around all over the place.

Shame, have to hope Clewett and Electromotive come true.

[Gerard C]

Good news, happy day! May be you can have the same result using the 6 other plugs. Your carb floats were clogged?

Can you use the DTA box together with the american distributor?

At least you know your hard work on the engine itself gives the expected results. Well done. The light at the end of the tunnel.

[S griffin]

Glad you've got the engine running, hopefully you can sort out the plug problem too. Hope you can find out what was wrong so you know for next time. Anyway best of luck, at least the major problem of the engine has been sorted. Let's hope the rest can be sorted too

[911thillclimber]

Obviously a good day to get the engine at least running.
Sounded very very crisp.
The carbs had been carefully stored but lying on their sides, they are downdraft carbs, and one float chamber in each carb has stuck closed. a simple strip down, clean and freed off did the trick.
First time I'd seen inside the carbs for 10 years! All good inside.

The drive gear on the distributor is too small and the radial back lash is huge, about 5 degrees, so any timing setting would be +/- 2.5 degrees, so hopeless.

All the bits that came with the Clewett system can be interfaced with the DTA unit if the XDi unit fails to come back to me.

4 week loss to me and a further £300

I have little faith in both USA companies involved.

[S griffin]

Yes it is a beautiful day where I am too. Glad the engine's running well. Bit of a mystery though what the problem was in the first place, hope you found out soon enough and it doesn't cost too much to do

[911thillclimber]

No mysteries!
The USA Clewett device is duff, and on it's way now to Virginia for fixing.

To get the engine running, just to be sure it actually works, I re-installed my original distributor and coil. This will only drive the top 6 plugs, not all 12, but at low revs that will work.
The carbs had 2 stuck floats but easily sorted. Pump on, carbs full, and Vrrrooom it ran.
Sounded great.

Just need to twiddle my thumbs for 4 weeks while the Clewett re-appears.

Hoping to do first event at Prescott on 23 April.