'86 fourtrak won't start if left for 2 weeks

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Hello all,

bought the rocky/fourtark recently and all is cool except that if left for a couple of weeks it won't start. turns over and almost catches but never quite gets there and battery ends up getting depleted. the battery is quite new and a decent one.

if left for a a week it will start but takes a dozen or so turns of the ignition to get it going. If you jump start it, it gets going right off.

Things I reckon it could be:
1. a short circuit somewhere is draining the battery (has an aftermarket immobiliser fitted so may be that)
2. needs new spark plugs
3. needs distributor cap cleaned and poinst checked
4. new HT leads

where should I start??

cheers all,

james

Service Intervals

Is it a Fourtrak or a Sportrak? Begin by servicing the vehicle, this way you will know all is ok in the engine department, and you will doubtless find any problems.

If it is fuel injection it could also be the fuel pressure is not up to the required pressure, to counteract this turn on the ignition and listen for the electric pump kicking in for a few seconds. If it does all is ok, but it may be on its way out, and not delivering enough pressure to the system, cranking the engine sends a signal to the pump to operate. Check the fuel filter also, if it is clogged it will not allow pressure to build up quickly.

Immobilisers are notorious for heavy electrical consumption, or it may be something else draining the battery. One option is to remove the fuses one by one, put an electrical tester with amps settings of a minimum of 10 amps across the fuse terminals, with the ignition switched off. This will identify which circuit is drawing current, and ho much current is actually being drawn from that fuse. Trace that fused circuit to all its components, and you will have your answer.

thanks, it's a fourtrak. i

thanks, it's a fourtrak. i think i will do a full service and new leads, cleaning points etc will help it fire but will check fuel fliter etc too. I also reckon you're probably right that there's something draining the battery so will see what the main cause it and sort it out. i hope it's just the immobiliser.

Damp

It is damp and leaking voltage. Spray all the electricals, especially plugs, HT leads, distributor, coil with WD40.
If diesel spray all over!

A good tip to locate leaking voltages:
Go out when dark and open the bonnet. Get someone to fire the engine and you look under the bonnet. Look for traces of 'light' where the voltage is leaking ... probably between coil and spark plugs.

Testing

If the battery is being drained, Maplins do a simple tester which simply replaces a fuse to test each fused circuit for power losses.
In addition they also do a relatively cheap intelligent battery charger, this connects to the battery and the mains, this charges the battery until it is full, then drops to a maintenence charge. If something such as an immobiliser is draining the battery over a period, then it would be worth investing in if the vehicle is stood for long periods. This also assumes that you have mains power accessible to the vehicle.

Immobilisers are notorious for draining batteries over long periods, and this was recently highlighted in one motoring journal.