Anybody got a 35DLM8 handy?
Anybody got a 35DLM8 handy?
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wedg1e

Original Poster:

27,034 posts

294 months

Sunday 16th October 2005
quotequote all
Distributor, with the ignition amplifier on the side...

Went to get the 390SE out for some more injection fun. Wouldn't start, battery flat. Arse.

So I put the charger on and went for a haircut.

When I got back, turned the key. Lots of spinning but wouldn't start. Odd, it normally goes first turn.
OK, check I plugged the ECU back in properly after the last session... that's OK. Hmmm.
Right, ignition on, flick the throttle, injectors click. As it happened I'd left a fuel pressure gauge on the rail and that was showing me the rail was full, and when the injectors fired the rail pressure went down by the amount you'd expect.

Right then, out with the injection tester :D

Plugged everything in, turned the key. Power and cranking were there but the 'bank firing' LEDs weren't lighting. Flick the throttle and they do.

OK then, scope on the ignition trigger line... no pulses. Eh? This worked fine last week.

Check the wiring to the coil, ignition amp etc; all OK.
HT lead on the rocker cover, turn the key, no spark. Check for 12v at the coil and ignition amp... that's OK.

Alright, let's use the multimeter on Amps range to manually fire the coil to earth... sparky spark. And if I did it fast enough the ECU started firing the injectors.

So that leaves the ignition amp. Where the hell am I going to get one of these at 4PM on a Saturday..?

I knew it was a waste of time trying Halfords but I went anyway (I needed some shoes and there's a Wynsors World of Sh!t Shoes next door)... no joy.

So I came back and half-heartedly started trawling the web for bits. By a bit of lateral thinking I arrived at the conclusion my mate would probably have an ignition amp, so I rang him up and he did.

Swapped the units over and... still no spark. Checked the pickup coil and it reads 19Megohms one way and 26MOhm the other! Now that's as near an open-circuit as you could wish to see, and the pickup off the dissy my mate gave me (not a V8 one) reads 1000 Ohms.

So either (a) both amps are US (although every resistance check I make is near as dammit the same on both) or (b) the pickup has gone o/c for no apparent reason!

Next question: has anyone got one handy that they can stick a meter across and confirm that the pickup reads rather less than 19MOhm...?

I wonder if this could be the root cause of my recent issues with the engine not revving past 5300 or so...?

Next plan with the injection tester is to add a square-wave generator so I can simulate ignition pulses!

hustlebabe

790 posts

255 months

Sunday 16th October 2005
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Wedge1...just don't go for the haircut...and stay in and get yer problems sorted....doh

tallbloke

10,376 posts

312 months

Sunday 16th October 2005
quotequote all
wedg1e said:

Next question: has anyone got one handy that they can stick a meter across and confirm that the pickup reads rather less than 19MOhm...?


Is there any way of getting at it through the wiring on the car Ian? If so, tell me which connector block to undo and which colour wires to put the probes across and I'll go over to Otley and test mine for you.

grahamw48

9,944 posts

267 months

Sunday 16th October 2005
quotequote all
Blimey Ian, could have stopped by and donated my motor's innards yesterday (on my way to Durham).

Have you got her fired up yet ?

wedg1e

Original Poster:

27,034 posts

294 months

Sunday 16th October 2005
quotequote all
tallbloke said:

wedg1e said:

Next question: has anyone got one handy that they can stick a meter across and confirm that the pickup reads rather less than 19MOhm...?



Is there any way of getting at it through the wiring on the car Ian? If so, tell me which connector block to undo and which colour wires to put the probes across and I'll go over to Otley and test mine for you.


Cheers Roger; you have to unscrew the ignition amp from the side of the dissy to get at the coil leadout wires...

wedg1e

Original Poster:

27,034 posts

294 months

Sunday 16th October 2005
quotequote all
grahamw48 said:
Blimey Ian, could have stopped by and donated my motor's innards yesterday (on my way to Durham).

Have you got her fired up yet ?


No...

wedg1e

Original Poster:

27,034 posts

294 months

Sunday 16th October 2005
quotequote all
Right, some progress.
It occurred to me that the dissy my mate gave me (whilst not a RV8 one) ws probably OK, so I refitted its ignition amp, plugged it into the TVR and turned the ignition on.
Holding the dissy against the rocker cover (the ignition amp is earthed through the dissy) I spun the rotor arm... and got sparks - AND the injectors started firing!
Tried my original amp on the same setup and that works OK as well.
So it's a clear-cut case of knackered pickup coil.

Just for a laugh I put an oscilloscope on the coil output of the spare dissy, put a cordless drill where the rotor arm should be and spun it up. There was 35v peak AC across it!

By a bit of Googling I've got in touch with a guy who specialises in Lucas ignition bits, he reckons he can supply a pickup (though he'd rather sell me a reconditioned distributor )....

Oh well, guess I can't do any more this weekend, may as well crack on with the bathroom...

GreenV8S

31,014 posts

313 months

Sunday 16th October 2005
quotequote all
My spare pickup measures 3k2 both ways, if that's any help? Does sound like you have a duff pickup there.

tallbloke

10,376 posts

312 months

Monday 17th October 2005
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wedg1e said:

Oh well, guess I can't do any more this weekend, may as well crack on with the bathroom...


Sorry Ian, I'd gone by the time you posted. Sounds like you found the problem though.

wedg1e

Original Poster:

27,034 posts

294 months

Monday 17th October 2005
quotequote all
tallbloke said:

wedg1e said:

Oh well, guess I can't do any more this weekend, may as well crack on with the bathroom...



Sorry Ian, I'd gone by the time you posted. Sounds like you found the problem though.


No probs. Is yours in bits yet?

adam quantrill

11,679 posts

271 months

Monday 17th October 2005
quotequote all
Why not wind yer own coil? Or even take off the old one and fix the break in the wire - odds on it's near the end.

Losing a couple of turns won't make a difference.

wedg1e

Original Poster:

27,034 posts

294 months

Monday 17th October 2005
quotequote all
adam quantrill said:
Why not wind yer own coil? Or even take off the old one and fix the break in the wire - odds on it's near the end.

Losing a couple of turns won't make a difference.


It's potted in epoxy. By the time I'd dismantled it you wouldn't be able to count the turns!

adam quantrill

11,679 posts

271 months

Monday 17th October 2005
quotequote all
Well you know what the voltage is with your drill setup - 35V p-p. So wind a 100-turn coil and measure that. Then scale up the number of turns by the ratio of the voltages.

350matt

3,895 posts

308 months

Monday 17th October 2005
quotequote all
Rimmer bros will sell you a new pick-up

Matt

wedg1e

Original Poster:

27,034 posts

294 months

Thursday 20th October 2005
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Right, got it sorted.
Replacement pickup dropped in, guessed the air gap, spun her over and she started first time.

The guy in question is a Graeme Dockree; he's down in Ramsgate. Although I didn't find him on Ebay, he sells Rangey stuff as 'docky57'. He also claims to specialise in rebuilding RV8 distributors and has all the spares. I can pass on his email if anyone needs anything...

rev-erend

21,619 posts

313 months

Thursday 20th October 2005
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My SEAC has been running like a dog for a while - so I replaced the dizzy cap and rotor arm as they did not look too healthy..

Got them from Rimmer bros - cost £18 and arrived PDQ
and I fitted them last night.

Happy to report that the car still works and seems smoother.. need to give it a proper drive to see if it's really much better

wedg1e

Original Poster:

27,034 posts

294 months

Saturday 22nd October 2005
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Just been out for a thrape, and the 5300 rpm limit has disappeared... it was heading for 7000 at one stage

Managed to prove that it's also not losing fuel pressure at high rpm, so it's just a matter of 'adjusting' the fuelling... especially as I scared the crap out of myself when the wheels started spinning in 2nd, never known it do that before!