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+--- Thread: Motor cuts out (/showthread.php?tid=2713)
Motor cuts out - Frank Macfarlane - 27-04-2019
Good eve My 1929 mulliner starts well but after approx 20/30 minutes it stops running .I recently had a problem with the carb as I mistakenly put a rubber washer under the inlet valve of the Z22 Zenith.
Petrol does leak out of barrel so obviously the levels are wrong. I suspect oI have done something wrong when replacing thr carburetor
Any thoughts on the above I cannot get it to start
RE: Motor cuts out - Howard Wright - 27-04-2019
Hi Frank
I just suffered from similar symptoms with an FZ22. In my case it was dirt in the tank, sufficient to block the exit tap and cause fuel starvation.
When the car stops, check the float chamber. If its dry then the problem is in the supply. Check the filter on the inlet to the chamber and the pipe back to the tank. If there is plenty of fuel in the float chamber it could be a blocked jet.
Bits of dirt sufficient to block a jet have a habit of settling back down the supply pipe and then move up it to cause mayhem after several miles.
Cheers
Howard
RE: Motor cuts out - Nick Malone - 29-04-2019
Hi Frank,
It may well be something to do with the carburettor but, if this ends up being all OK, it may be a dodgy coil. I remember 40+ years ago my dad's RM saloon kept running for about 20 minutes before stopping dead as if it was fuel starvation. After messing about with the carburettor for a bit - cleaning jets etc. it would start and run fine for a bit before repeating the process. We drove home about 200 miles in about 20 "stages" like this.
In the end it proved to be a dodgy coil which was over heating. Our frequent stops and fiddling about in the wrong area gave it time to cool down and for everything to appear normal for a while.
Don't know if that helps at all?
Best wishes,
Nick
RE: Motor cuts out - JonE - 29-04-2019
Nick - so will testing the resistance across the LT connections show that if done when its hot? If so would it get higher than 1.8, or reduce??
RE: Motor cuts out - Nick Malone - 29-04-2019
Hi Jon,
To be honest, I don't know the answer to your question. I was taught to test a coil by switching on the ignition; removing the distributor cap; running the HT lead from the coil to earth and opening and closing the points. If there's a spark, it's OK, if not the coil is on its way out. You can obviously do this hot or cold and see what happens.
Don't know if that helps?
Best wishes,
Nick
RE: Motor cuts out - Phil Kingdom - 29-04-2019
I had a similar problem with a Hillman, it would run fine till it had warmed up, them cut out and refuse to start until it had cooled down, after changing/checking every thing it turned out to be a hairline crack in the rotor arm ( the last thing to change ) that opened up when hot and shorted to earth.