Slow cranking - HELP !!!!!!

Land Rover 90 from 1986 with a 200Tdi engine.

Had a "sticking" starter motor and eventually got fed up with hitting it with a hammer to release it. So I ordered a new one from DLS and fitted it. Virtually the same as the old one except it doesn't have the connection for the "additional" earth strap on the end.

Anyway all fitted fine and fired up 1st time no probs. However over the following days the speed it spun the engine started to become slow occasionally - sounding as if it was struggling. Logically I thought battery - so bought a new one from the motor factors. they tested the old one and confirmed that it was on it's way out (7 years old). In order to "guarantee" the new battery they tested it in place and confirmed that the alternator was providing enough power to recharge.

All good....except the starter still struggles even with the new battery. Usually it's the first start in the morning after being left overnight but sometimes even when "hot" it's slow to crank over.

After researching some more today I've cleaned the battery to gearbox earth strap and other than a couple of "threads" being no longer attached to the end connection it seems fine - still same problem though.

This morning again very slow cranking so I put the battery on charge and within 15mins it was fully charged - so am pretty certain that it's not the battery nor the alternator I have however ordered a new Denso alternator, just in case, as it was at a good price and also a new earth strap.

The old starter would turn over fast and always started the engine no probs but it was sticking too often so needed to change.

I'm starting to run out of ideas and it's also starting to cost too much.....anyone got any ideas ??????????????

Faulty starter motor ! Connect multimeter to battery terminals , crank engine over ,watch meter if it drops drastically from its full voltage then the starter is drawing too many amperes and volts !! Check all connections etc ! Could be a comm winding failing , carbon brush or bearing going tight either way you will need to take it off if it's faulty !! But if the voltage drops drastically while cranking it is possible that the battery has a fault , eliminate by using alternative battery !

Thanks for the reply :clap2:

I had the same result (or lack of) with the old battery so am pretty certain that the battery is not faulty (also the motor factors checked the new battery whilst in situ in order to give me the 2 year warrantee).

I'll try checking the voltage across the battery whilst cranking as you suggest but am starting to think that it may well be a duff starter motor as originally this was the only thing I changed and the problem arrived once the new starter was installed.

Getting the impression that I'm going round in expensive circles replacing parts that don't need changing on the basis that the new starter is fine whereas it's possible it's not. I've also noticed that the "symptons" are getting worse - before it was only once now and again, now it's almost everytime I start up from "cold".

Only had the starter one month so will call DFS tomorrow and see what they want to do.

Anyone else any ideas???

Changed the main earth lead yesterday and also put on a new battery terminal for the +ve.

Started the car 5 times today no probs - nice and fast cranking but the 6th time back to slow cranking - will call DFS in the morning to see what they suggest.

Just a suggestion what cold cranking amps is in the battery you have got as in the new one?

When I bought my last battery I then learned about the cold cranking amps as in the bigger the ampage the more you going to get when starting !!

Sorry I don't know what the cold amperes are but did some further investigation today and have discovered the following:

Took off the new starter and wired it directly up to the old battery.
Did the same exercise with the old starter.
Old starter is considerably faster than new one = problem with the new one.
Packaged up and heading back to DLS tomorrow and they've ordered me a new one.

Their mechanic had confirmed, prior to my tests, that it sounded most likely to be a bad new starter motor.

Hoping the new new one actually works this time as changing them out is becoming a pain.

LVC, what was the outcome, was it the starter motor? I am having similar problems, over time the cranking has got slower and slower, I thought the battery was the fault so changed it, now she won't even turn over, I'm going to have a look at the starter tommorow

Russward said:

LVC, what was the outcome, was it the starter motor? I am having similar problems, over time the cranking has got slower and slower, I thought the battery was the fault so changed it, now she won't even turn over, I'm going to have a look at the starter tommorow

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Looks like the new starters are just less quick on turnover - if I preheat now (never had to before) then she fires up first time.

Sounds to me more like you have a problem with the "juice" getting to the starter motor or the starter motor is stuck, from what I learnt doing mine this could be any of the following:

1: Starter motor cog stuck in the flywheel (whack the body of the stater motor with a hammer to release it).
2: Negative lead (from battery to chassis) not making good contact.
3: 2nd Negative lead (from engine to chasis - if you have one) not making good contact.
4: Main +ve cable to the stater motor is badly connected.
5: Starter solenoid not doing it's job


Note. option no.1 was the original reason why I started messing around with the stater motor in the first place and only changed it as it was getting stuck on a regular basis and I got fed up with having to open the bonnet and give it a whack.

If when you turn the key all the lights work as normal but you get no noise from the starter motor I'd give it a whack in case it's stuck. if not checking the connections are good for the wires - if you fancy it you can take them off and retighten with some "petroleum jelly" to protect them.

Good luck.