question Testing a staring circuit on a 24v Land Rover

[Rover8FFR]

I have ascertained that my engine is not seized and had added some lubrication (Redex) through the spark plug openings.

 

Turned the motor by hand a dozen times and all was well.

 

Attached some batteries and attempted to crank the engine over to pumps some oil around, without firing up of course just yet.

 

Ignition lights and oil pressure lights came on but did not engage starter motor. Key turn does create a click that suggests the solenoid was engaging.

 

I didn't get a light when using a circuit tester on the solenoid contacts or the terminals on the starter motor so I am guessing starter solenoid / starter motor is at fault.

 

Are there some tests that can be done on the starter in-situ to see if it is seized or bendix/ bushes are gone.

 

Answers on a post card please :-D

[trustmeimamechanic]

Not realy , if 24v is arriving at the soleniod then anything else is internal to the starter , you could try using a wire from the batt straight to the soleniod to eliminate any faults in the system down to the soleniod. If you are using just a test light then all you are proving is that a supply of 24v is reaching the soleniod .... one strand of wire will do this... you need to know that the starter has a supply of 24v that can also give the required amps to the starter.

Check all the connections both + and earth , take them off.. clean them with some emerey cloth and then make sure they are tight . Check the earth lead from the chassis to the engine block .

[rbrtcrowther]

It may just be a bit sticky with standing. turn and hold the key on for a few seconds, If there is a click and the lights go out or dim there may be a bad main connection (Battery leads) , A flat Battery or the starter is pulling huge current and needs to be looked at. The ignition lights should come back on when you release the key. ( Holding the key in the start position for a couple of seconds may make the the bad conection hot so you can find it )

If there is a klick and the light go out compleatly and stay off when you release the key you have a bad connection usually on a battery lead.

If you get a click and the lights stay bright with the key held in start positon the starter is dodgy.

i would give it a tap with a hammer then try again you might find it will click when you try the key again. If there are two of you one hold the key in start the other give the startar a slap with a small hammer. If you can get it clicking when you turn the key try flicking the key for a while it might just come to life.

If you still have no joy jab a screwdriver accross the big contacts on the solanoid and see if it spins over. Just make sure it's not in gear :cool2:

[trustmeimamechanic]

"[ ( Holding the key in the start position for a couple of seconds may make the the bad conection hot so you can find it )"

 

Reminds me of when I was on an electrical course with some lads from Ireland... we were set various tests and had vehicles with faults placed on them that we had to fix .One of the Irish lads explained how electricity was not invisible but was infact like smoke.... he went on to say if you had a machine that kept blowing fuses then all you had to do was hold your penknife across the fuse terminals and you would see where the problem was because the electricity would leak out like smoke from the damaged wire. The blade of his penknife looked like a saw it had so many burns on it .

 

 

"If you still have no joy jab a screwdriver accross the big contacts on the solanoid and see if it spins over. Just make sure it's not in gear :cool2:

[Rover8FFR]

I did wonder about bridging the starter contacts, but if the starter is jammed due to being stood for years or internal corrosion has occcured then is this wise? Assume screwdriver needs a large handle to insulate from a big shock!

 

I have a new solenoid as a spare so may trie that. What if my circuit tester is not showing a current but ignition lights up and a click is heard when ignition is on!

 

All good fun :nut:

[Tony B]

Have you tried Imidiate Action Number 1? Hit starter with 'ammer? Would be worth the effort of taking the starter off and playing with it on the bench. You can always start the engine via a starting handle!

[fv1609]

I did wonder about bridging the starter contacts,

 

Just be very careful, once I lay under a 101 to do just that. Although it started fine, the spark caused a particle of molten metal to land near my eye. I have never done that trick again.

[Rover8FFR]

Just be very careful, once I lay under a 101 to do just that. Although it started fine, the spark caused a particle of molten metal to land near my eye. I have never done that trick again.

 

Yes of course. I will be tackling this from above. Have removed contacts so will probably remove to inspect first and if needs be fit another CAV starter as I have 3 24volters spare.

 

A replaced starter may just assist, unless the starter solenoid is suspect, but have a brand new replacement for that so will use a process of elimination as it were.

 

Thanks for evryones comments as always.