Starter circuit problems

[MickW]

Hi

My normally good Excel won't start and I suspect trouble like a bad earth or cracked heavy duty cable. (All this is nothing to do with ignition circuits. They are a separate bad dream!)
I have the Service Notes & wonder if the Start Relay is failing.
Where is the Start Relay physically located on an early car (old dash with fuse box near right ankle)? Suspect it's on pedal box or above fuse box - but I haven't found a pic of the old setup in my Service Notes - only a pic of the new setup.

I have had two different starter motors on it & the same result. The trouble seems the behaviour of the solenoid (on the side) rather than the motor itself.
When engaged it doesn't go in properly and "click - click - clicks".
This is almost certainly a lack of current under start conditions. A possible problem is the earth, but this does measure as very few ohms of resistance. [But this test won't show a cracked heavy duty cable.]
I've tested by bypassing the ignition sw. with a shorting link. Sometimes it starts, sometimes it doesn't. I plan to do more testing on this today.

Although I have more work to do, I thought of posting this now as one of you might have solved this before.
fingers crossed - TIA.
MickW.

[Steve C]

I had this problem (click click click) .. remove and clean the earth strap to the block on the right hand side of the engine. Mine was still tight but had corroded up and wasnt conducting properly. (that'll teach me for cleaning all the oil off the block with engine cleaner a month or two before - it was fine for 17 years covered in oil!).

As a test, you could run a long jump lead from the battery neg to somewhere on the engine. If that solves it, it's probably the bad earth mentioned above.

Another way is to measure the voltage from battery neg to the engine block while cranking. This is measuring the voltage drop on the earth circuit, any more than 0.5 - 1v when cranking and you have a bad earth. DO NOT use an AMPs setting or you'll blow a fuse in your meter at best, at worst, melt it and / or the leads!

[MickW]

Hi Steve

I have tried a large lead between battery -ve and the engine block. This hasn't made any difference - still no start. Am going to try it with a battery & jump leads (beside the front of the car) going direct to the starter motor. Then using a bit of wire to "jump" the solenoid bit in place of the car's red/white lead from the ign sw. This is because it's driving me nuts & I know it can't defy the laws of physics. So, starting with a completely separate system might give me an answer.

Will also do a cranking test.

Cheers,

MickW.

[Redexcel]

I've had starting problems twice in my 13 years of ownership. Once it was the earth connection on the block, as per Steve's suggestion. The return current was using the speedo cable as an earth, and it melted the speedo's innards

The other time it was the start relay, one of the bank of relays by the driver's right shin. Don't be fooled by the headlamps going out when you try to start the car though. They're meant to do that to reduce the load on the battery.

[MickW]

Well, I have fitted a new (reconditioned) starter motor and fitted an earthing lead between the solenoid casing and the earthing bolt that holds the coil to the bulkhead. [Looked at an another Excel & noticed it had one.] This is probably a good idea anyway, as it would save the "melting speedo" problem if the earth strap became dodgy.

This has temporarily solved the problem. I will shortly be removing & cleaning the engine earth strap and engine bay -ve lead.

May also recheck & clean the chassis earth near the diff, although I know mine is good because I cleaned it a few months ago.

So there we have it for this one - recon starter & clean earths recommended.

MickW

[htiek]

Well, this lunchtime I thought the Excel was finally going to leave me stranded. The infamous turn the key and only hear a clicking relay under the dash. Had a listen under the bonnet but no sound at starter solenoid. Aha, I thought, I'm sure I have read about this somewhere on the forum recently. As it was sleeting down (who needs lunch anyway!) I retired back to the office for a bit of interweb forum surfing. A read of this post and a call to a another local Excel owner and we had agreed on the start relay being the likely culprit.
A trip to the workshop for a piece of electrical wire and, come going home time, ignition on, air filter unclipped to get at starter motor, jump between big red and little red/white wire on the solenoid and she's away.
Once I got her home, could I get the relay to stop working again? Could I heck as like! Another one of these self-repairing annoying intermittent faults. New relay at the weekend methinks!
Oh well, Suzuki Jeep for the rest of the week...bounce, bounce...

Thanks to everyone who contributes to this forum, it really is a wonderful resource.

Cheers,

Keith