Starter motor question

[Cuppa]

General mechanical enquiry - not Patrol specific.
When starting the Nissan ED33 motor in our bus the last few times first turn of the key often results in a graunching sound without the motor turning over. Subsequent attempts start the motor OK. It seems obvious that there will be wear on the starter pinion...... & better to rectify before it strands us somewhere.
But..... I'm unsure if the wear is most likely on the starter motor pinion itself, or the ring gear it engages with. I'm hoping that just replacing the starter motor will fix the issue.
Would welcome your thoughts.

Cuppa

[lorrieandjas]

Hi Cuppa - just trying to get a feel for the sound it makes - not a clicking sound like the solenoid?

Jas

[Cuppa]

No Jas, not clicking, not the solenoid.
It's the sound that worn gears make when they are slipping/failing to mesh.... I think.
Turn the key a second time & most times it engages & starts.


Cuppa

[mudnut]

Unfortunately, Cuppa, you wont know until you take the starter motor out and have a look. I would suggest you check all of the electrical connections to the starter, it may not be getting enough power to throw the starter pinion out to mesh intermittently. Or there may be a plate at the bottom of the bell housing, when taken off, you may be able to see the ring gear.

[Alitis007]

If its a squawk type sound more then likely it will be wear on the ring gear from the startermotor pinion gear. If you can easily view the starter, remove it ( with the battery disconnected) and rotate the motor manually by the crank shaft bolt ( clockwise) and inspect the teeth on the ring gear and starter. 4cyl engines only stop on 2 different sides of the flywheel, 6 cyl 3 and 8 cyl 4 more then likely there will be teeth missing but on the rare occasion the teeth on the starter could only be worn.

Best bet is to remove it and inspect like i said earlier.

[threedogs]

might not be throwing the solenoid out far enough, is the battery as good as the one in your ute for example.
only has to be a little under par to play up.

[Cuppa]

Thanks folks, makes sense, I just wanted it to be easy!
Batteries (24v) are optima yellow tops in excellent condition & maintained on a Ctek charger. When the starter turns over the motor it does so with gusto, almost instant start.
The engine (4 cyl diesel) was replaced with a second hand engine about 10,000kms ago, but the starter motor off the original engine was fitted.

Cuppa

[threedogs]

You'll find motor stops in same spot everytime, With a large screw driver or Socket rotate motor
1/4 of a turn and try, ring gear will be new in this area. Might sound dumb but its true, XF falcon
were famous for it

[Parksy]

Mums EA was famous for this too. My gq makes this noise occasionally, but the 2nd turn of the key gets it started. If it was missing a tooth you would know about it. Makes a click, click, click noise every rotation the missing tooth makes with the starter.

[threedogs]

You may want to wire a relay to the starter. ??

[Cuppa]

You'll find motor stops in same spot everytime, With a large screw driver or Socket rotate motor
1/4 of a turn and try, ring gear will be new in this area. Might sound dumb but its true, EF falcon
were famous for it

So are you saying that with the starter motor removed, that rotating the motor 90 degrees that the motor will always then stop in this 'new' position? If so that sounds a better option than having to drop the motor to get a new ring gear fitted. Please confirm.

Follow on question: if I were doing this on a petrol motor I would remove the spark plugs to reduce compression & make turning the motor easier. On a diesel would I remove the glow plugs to achieve the same thing?

Cuppa

[threedogs]

Thats only telling you the ring gear or the gear on starter is U/S, You're turning motor to reveal fresh teeth.
I'd be pulling the starter out and inspecting that first, you might be able to reverse the cog on the starter, ???

[my third 256]

So are you saying that with the starter motor removed, that rotating the motor 90 degrees that the motor will always then stop in this 'new' position? If so that sounds a better option than having to drop the motor to get a new ring gear fitted. Please confirm.

Follow on question: if I were doing this on a petrol motor I would remove the spark plugs to reduce compression & make turning the motor easier. On a diesel would I remove the glow plugs to achieve the same thing?

Cuppa
no the motor will always stop in the same position on my gq i had this problem every now and then
if it kept grinding i would put it in gear and give it a push maybe 30 cm is all you need to shift the ring gear off the warn tooth

[Alitis007]

4 cylinder engines stop in 2 different positions, 6 cylinder engines stop in 3 different positions and 8 cylinder engines stop in 4. Your Ed33 being a 4 stops in 2 thats why it OCCASIONALLY does it.

[threedogs]

Only knew the 3 positions for the 6 cly, Thanks Alitis

[Yendor]

4 cylinder engines stop in 2 different positions, 6 cylinder engines stop in 3 different positions and 8 cylinder engines stop in 4. Your Ed33 being a 4 stops in 2 thats why it OCCASIONALLY does it.

It's like banging your head against a brick wall at times. ;)

[Alitis007]

It's like banging your head against a brick wall at times. ;)

Ahhh well something has got to give lol

[Alitis007]

If its a squawk type sound more then likely it will be wear on the ring gear from the startermotor pinion gear. If you can easily view the starter, remove it ( with the battery disconnected) and rotate the motor manually by the crank shaft bolt ( clockwise) and inspect the teeth on the ring gear and starter. 4cyl engines only stop on 2 different sides of the flywheel, 6 cyl 3 and 8 cyl 4 more then likely there will be teeth missing but on the rare occasion the teeth on the starter could only be worn.

Best bet is to remove it and inspect like i said earlier.

Just incase you missed this Cuppa!!

[Alitis007]

Follow on question: if I were doing this on a petrol motor I would remove the spark plugs to reduce compression & make turning the motor easier. On a diesel would I remove the glow plugs to achieve the same thing?

Cuppa

You can do that but older diesels have a lower compression ratio so turning it slowly should see you thru it, just need to give the biceps a lil work out.

[the ferret]

My bet is the ring gear Cuppa, motor needs to come out, but do as TD says and turn the motor a bit then try.
Cheers, the ferret.

[mudnut]

Hey, Cuppa, I'm interested to find out what you have discovered about the problem.

[Cuppa]

Hey, Cuppa, I'm interested to find out what you have discovered about the problem.

Nothing as yet mudnut. Have put off the job of crawling under the bus because of a) it's been freezing cold & b) I took a chunk out of my thumb doing some woodwork (with cold hands).

Cuppa

[mudnut]

That's no good, what were you making?

[Cuppa]

That's no good, what were you making?

A bottom rail of a window to replace the rotted out one.
I have one of those portable Triton 'Superjaws' vices & caught myself in it's mechanism taking a chunk of flesh out of the face of the thumb. Amazing how disabling such a 'minor' injury can be.

Cuppa

[mudnut]

Youch !! Cringing at the thought of that, mate. Hope it heals quickly.

[Dales300exc]

You don't need to remove spark plugs, glow plugs or anything else to turn over an engine. Your turning it slow enough that any cylinder pressure is bled off past the rings before you try to move it again.

Replace a starter the other week on a small truck due to this. Ring gear had minimal wear.