38 replies to this topic

[bigrob]

Hi guys.
My engine has an inertia starter on it. When i turn it over, the motor spins, lots of noise, but its not engaging. It has 10 teeth and the ring gear has 129 if i remember correctly. I tried a 9 tooth starter but that did exactly the same thing. Please help as its the only thing holding me back from the mot.
Cheers guys
Rob

[new_van_man]

try a bit of grease on spindle, sounds like its not engaging...

[bigrob]

Yeah i tried that. Free'd everything and greased it all. Anything else i could try?

[KernowCooper]

sounds like the solenoid is not throwing the gear in, so motor is spinning and not being engaged into the ring gear.

 

Take it off on the floor and with jump leads connect the red to the top solenoid terminal the black jump lead to the starter case now use a short jumper wire to the small lucar to the red clip on the jump lead, the starter should throw the gear out fully.

 

N.B put one foot on the starter motor when doing the test its powerful enough to jump about unsupported.

[bigrob]

Cheers mate i'll give that a try tomorrow. So if the gear throws out does that mean everythings working as it should?

[bigrob]

Right so ive been out this morning and tested both my current starter motors in the way you said. They're both just spinning and nothing else. One of the motors i stripped down and re greased. But like i say, they're just spinning and nothing else.
I put the cleaned up and regreased motor in the car and again, just spinning and not engaging. Whats the next step? Cheers for your help so far

[Captain Mainwaring]

sounds like the solenoid is not throwing the gear in, so motor is spinning and not being engaged into the ring gear.

 

Take it off on the floor and with jump leads connect the red to the top solenoid terminal the black jump lead to the starter case now use a short jumper wire to the small lucar to the red clip on the jump lead, the starter should throw the gear out fully.

 

N.B put one foot on the starter motor when doing the test its powerful enough to jump about unsupported.

 

It's an inertia starter. Is the bendix free to move backwards and forward if you turn it by hand?

 

As an aside, a bendix drive needs to be clean and dry....no grease. Wash the thing off with petrol until the spiral gear is clean and dry. The pinion has to be able to move along the spiral with no effort....also check that the spring isn't binding in the spring cup.

 

When you ran it up did the shaft run completely true? Shafts can get slightly bent for a variety of reasons...obviously the drive gear won't move if that happens.

[bigrob]

Yeah it moves freely by hand and springs back to the original postion. the shaft spins straight with no wobble. I've cleaned the grease off too.

[Captain Mainwaring]

Yeah it moves freely by hand and springs back to the original postion. the shaft spins straight with no wobble. I've cleaned the grease off too.

 

Springs back? There should be a very light anti rattle spring in there which prevents the bendix from shaking along the shaft and crunching the flywheel, but it's really fairly weak.

 

These starters haven't been rebuilt at all have they?

If you run the starter and VERY CAREFULLY brake the bendix with a small bit of dowel or the like, does the gear wind in?

 

(if you're really stuck...and we can't solve this - run the thing to my old mate Phil in Leeming Rd Borehamwood - Autocomponents is what I think he trades as)

Edited by Captain Mainwaring, 10 August 2013 - 09:52 AM.

[bigrob]

When i rotate the bendix down the shaft towards the motor housing, and then let go, it winds itself back up the shaft to the original position.
No i dont think they've been rebuilt. The fella i got the car off said its the original

[Captain Mainwaring]

OK, the only reason I asked was it was possible it could have been rotating the wrong way.

 

How strong is the rewind effect? it should be quite light. 

 

It does sound like they are lazy - they need to run up to speed quite quick to flick the Bendix along the shaft. 

[bigrob]

Yeah it is very light, no real resistance. Would it perhaps have something to do with the battery condition? It sounds ok if that makes sense, but its a fairly old looking halfords thing

[Captain Mainwaring]

Did you use that same battery to do the static tests on the floor?

Roughly how long did it take for the starter to hit full speed? 

It needs to be quite rapid for the bendix to live up to it's name.

[bigrob]

Yeah i used the same battery. And not for long. Just long enough to see it spin really

[bigrob]

Just been out and re tested both the 9 tooth and 10 tooth out of the car for long enough to see whats happening.
As soon as the motor is connected to the battery the bendix gear flicks down the shaft as if it would be engaging, then as the motor spins up it slowly works its way back to the resting position
It also seems to spin alot faster out of the car

Edited by bigrob, 10 August 2013 - 12:50 PM.