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Hi All

Getting well on with my resto now and as most things seem to work I’m trying the first engine start in my ownership and for well over a decade, but I can’t get it to fire and so I need a bit of advice.

So it’s got a rebuilt engine (by me) as well as new electrics and the pump, starter and ignition all seem to work. All Pi gear was refurbed properly, by Neil F, and is completely standard so that bit should be good.

Now after messing around with quite a few niggly issues, ignition and leaks, all of those seem to be sorted and I have a sparking ignition and leak free fuel system.

I’ve cranked the engine over for a while (without plugs) and got oil pressure. I won’t say how much as you might all laugh, but if someone can give me an idea of what the gauge might show on just a starter motor crank that would be great. I might then be happy or not as the case may be, lol.

I’ve left the Ign on so the pump is running a good while a good to try to prime the system with fuel and get rid of the air, but are there any tricks to whether that has worked or not?

So i connected everything up and attempted to start it several times with no joy. :(

I tested for a spark and thats ok but after the jam jar test no fuel at the injectors.

So the questions that occur to me are have I left the fuel pump running enough to get enough fuel in the MU to get to the injectors? So can I just leave it pumping on the ignition or do I have to crank it over for ages (how long?) or will that damage the pump?

Or after reading some other posts on the forum do I have another issue? One post says if the injector pipes are not pulsing (they aren’t) the plastic dog driver could be broken? Is that correct and how can I tell unless I pull the MU.

So a list of stuff I should I check would be fab.

Cheers

Keith

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The pump runs all the time the ignition is on, so no harm in leaving it to prime for a while (you might want to disconnect the points cable so they don't burn).

The injector pipes pulse because of the pressure to open the injector and the release of that pressure when it does. Until you have fuel opening the injector it won't pulse.

Whilst priming the system off the pump helps, it will only bring the pressure to the MU, it then has a small volume to push to each injector. you could try cracking open number six line on the MU to see if fuel is present, if it is, it's a case of cranking over to push it up to the injectors. You could try and back fill the lines with fuel to speed it up.

Can you feel the MU rotating while it's being cranked over, again you could undo number six line and move the engine by hand whilst observing the rotor turning through the hole to confirm the plastic drive is good and working.

Gareth

Edited by Mk2 Chopper
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Hi Keith,

I had issues to, finally it appeared ignition timing.

Maybe let the pump run longer, remove feed to ignition to avoid overheatin coul and put battery charger on battery to support battery. And remove the plugs.

I had the injectors out and kept them vertical with pump running, and when I pulled on the tips, first some air came out, than air/fuel bells, then fuel. I cranked the engine just for 2 seconds or so every minute or so, my idea was that this would connect different injectors to the MU-inlet (105 psi) but I’m not sure if this is true, but it worked.

Think I had 60 psi while cranking.

Regards,

Waldi

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Hi Keith

i’m at the same stage, I got it to fire by injecting some petrol using a syringe at the weekend, then it started running -wheeee!!!

The neighbours must have thought I’d gone crazy (er) dancing round the garage!

I think the fuel takes time to get round to the injectors - it just takes time - keep cranking.

hope it works.

cheers Neil 

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