Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: Fandango80 on February 25, 2009, 11:11:38 AM

Title: 1974 CJ Starter motor problems
Post by: Fandango80 on February 25, 2009, 11:11:38 AM
Hi Guys,

Firstly, Sorry for not posting any pics yet, i got sent abroad before i could get any decent pics. They will follow soon!

Well my 100 quid bargain has started to bite back.  :toimonster: When I tried to turn it over, the starter would not engage work. I connected a 12v supply directly to the positive terminal and negative to body with jump leads but nothing happened apart from the crock clip would arc out as if i was touching the pos and neg together. i removed the starter (surprisingly easily) and tried the same but no luck. The pinion gear moves freely and the recoil is smooth and plush. On inspection, the internals look to be in mint condition. Am I missing something really obvious or does it need to be overhauled? Does anyone know of any good UK companies that recondition these beasts?

Cheers.
Title: Re: 1974 CJ Starter motor problems
Post by: Ric Jacques on February 26, 2009, 09:27:30 PM
You need to earth the starter body to something.  It should be earthed by connection to the engine but make sure the engine has a good earthing strap to the body.......
Title: Re: 1974 CJ Starter motor problems
Post by: Bubba on February 26, 2009, 09:34:18 PM
you can do it on the floor put the earth  jump lead on the main body then jus lightly touch the red pos jump lead on the pos terminal it should spin and you can see wether the dog jumps out
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on February 27, 2009, 06:59:11 AM
Cheers Guys,

So basically, the earthing strap from the engine to body is not connecting properly?
Kinda weird though because when the starter was on the floor, i connected the negative jump lead to the body of the starter and the positive to the prong on the side. I dont see how the chassis of the vehicle would effect it?

Cheers
Title: Re: 1974 CJ Starter motor problems
Post by: Bubba on February 27, 2009, 04:18:32 PM
the engine and gearbox sit on rubber mounts so is insulated form the battery so the earth path needs to be good
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on February 28, 2009, 01:39:31 AM
Yeah i understand that if the engine wasnt earthed, the starter would not respond but i am getting huge sparks from the positive lead when contacted with the positive terminal on the starter which indicates a good earth (at least good enough to create an ark hot enough to weld with!) It is like the positive terminal is directly earthed without even going through the motor its self. Plus, I took the motor off the engine and connected it directly to a battery (Pos to the terminal and Neg to body of motor) and still the same massive sparks!  


Very confusing  #-o
Title: Re: 1974 CJ Starter motor problems
Post by: Bubba on February 28, 2009, 08:46:38 AM
i would say the smoke has escaped therefore it is fuckedd  full strip is needed  maybe the pos terminal has been twisted rond and ripped the insulation alowing it to short to earth
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on February 28, 2009, 08:59:52 AM
Quote from: "V8 Bubba"
i would say the smoke has escaped therefore it is fuckedd  full strip is needed  maybe the pos terminal has been twisted rond and ripped the insulation alowing it to short to earth

Yea, good thought. Im gonna give it to someone who specialises in em and get them to give it an overhaul.

No point messing round with it. Not a good start (boom boom) but lets hope its not all like this- you lnow it will be!
Title: Re: 1974 CJ Starter motor problems
Post by: eastryjeep on March 04, 2009, 04:35:15 PM
Before spending too much, strip the thing to bits and clean it up nicely, lots of petrol, warmish day etc. Then wrap the comutator with masking tape and spray a can full of laquer over the rotor making sure it runs down between the windings to reinforce any insulation that may be breaking down in there. Next clean up the brushes and make sure they can slide freely in the housing. When reassembling ensure that there is not too much clearance between the shaft and the bushes (this is a common failing which allows the rotor to rub or jam against the stator giving very high current draw to the point of even replicating your 'dead short').

If the above doesnt help, you havent lost anything, but it works for my '77 starter every time!
Title: Re: 1974 CJ Starter motor problems
Post by: tim_aka_tim on March 04, 2009, 04:42:55 PM
Quote from: "V8 Bubba"
i would say the smoke has escaped therefore it is fuckedd  full strip is needed  maybe the pos terminal has been twisted rond and ripped the insulation alowing it to short to earth

That made me laugh. For those of you who think he's barmy, this is what he's on about.....

Quote from: "Some random bloke"
Positive ground depends upon proper circuit functioning, the transmission of negative ions by retention of the visible spectral manifestation known as "smoke". Smoke is the thing that makes electrical circuits work; we know this to be true because every time one lets the smoke out of the electrical system, it stops working. This can be verified repeatedly through empirical testing.

When, for example, the smoke escapes from an electrical component (i.e., say, a Lucas voltage regulator), it will be observed that the component stops working. The function of the wire harness is to carry the smoke from one device to another; when the wire harness "springs a leak", and lets all the smoke out of the system, nothing works afterwards. Starter motors were frowned upon in British Automobiles for some time, largely because they consume large quantities of smoke, requiring very large wires.

It has been noted that Lucas components are possibly more prone to electrical leakage than Bosch or generic Japanese electrics. Experts point out that this is because Lucas is British and all things British leak. British engines leak oil, shock absorbers, hydraulic forks and disk brakes leak fluid, British tires leak air and the British defense establishment leaks secrets...so, naturally, British electronics leak smoke.
Title: Re: 1974 CJ Starter motor problems
Post by: Bubba on March 04, 2009, 05:22:55 PM
yup most things contain smoke once its all gone it no work and you are screwed
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on March 05, 2009, 01:52:29 AM
Quote from: "eastryjeep"
Before spending too much, strip the thing to bits and clean it up nicely, lots of petrol, warmish day etc. Then wrap the comutator with masking tape and spray a can full of laquer over the rotor making sure it runs down between the windings to reinforce any insulation that may be breaking down in there. Next clean up the brushes and make sure they can slide freely in the housing. When reassembling ensure that there is not too much clearance between the shaft and the bushes (this is a common failing which allows the rotor to rub or jam against the stator giving very high current draw to the point of even replicating your 'dead short').

If the above doesnt help, you havent lost anything, but it works for my '77 starter every time!

Good plan! I have already stripped the starter and despite its slightly rusty appearance on the outside the inside looks clean as a whistle. I was really surprised how easily it came off and apart- who ever last had this thing coated all the bolts in copper slip! Will let y'all know how it goes.

As for tim, nice cut and paste job but what are you banging on about? :shock:  but yes, from my experiance, Lucas is generally crap.
Title: Re: 1974 CJ Starter motor problems
Post by: tim_aka_tim on March 05, 2009, 02:13:50 PM
Quote from: "Fandango80"

As for tim, nice cut and paste job but what are you banging on about? :shock:  but yes, from my experiance, Lucas is generally crap.

It's called 'humour'.
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on March 06, 2009, 01:48:32 AM
Quote from: "tim_aka_tim"
Quote from: "Fandango80"

As for tim, nice cut and paste job but what are you banging on about? :rolleyes:
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on March 06, 2009, 06:29:10 AM
OK guys,

I have found a starter brand new for 100 big ones... Im tempted to go for it as when i had my alternator overhauled, it cost me about 60 quid and that was a common as muck bosch  unit from a golf. So... i am assuming that to recon a starter from a prehistoric jeep will be at least 60 if not more. (assuming the clean and laquer doesnt do the trick!)

What do ya think... any ideas?
Title: Re: 1974 CJ Starter motor problems
Post by: tim_aka_tim on March 06, 2009, 02:36:45 PM
Rockauto have a remanufactured starter for a
3.8, 4.2 and 5.0 for $132.54 delivered to UK.
I know the exchange rate is poo, but still beats 100 quid.
I'd shop around a little more.
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on March 07, 2009, 12:17:34 AM
Quote from: "tim_aka_tim"
Rockauto have a remanufactured starter for a
3.8, 4.2 and 5.0 for $132.54 delivered to UK.
I know the exchange rate is poo, but still beats 100 quid.
I'd shop around a little more.

Cheers tim,
 think that works out bout the same but will continue to hunt about.

Ur right- exchange rate is dissapointing!

Cheers
Title: Re: 1974 CJ Starter motor problems
Post by: PtP on March 07, 2009, 11:53:01 PM
Is this one any good?: http://cgi.ebay.co.uk/JEEP-WRANGLER-STA ... 240%3A1318 (http://cgi.ebay.co.uk/JEEP-WRANGLER-STARTER-MOTOR_W0QQitemZ320346236638QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item320346236638&_trksid=p3286.c0.m14&_trkparms=66%3A2%7C65%3A1%7C39%3A1%7C240%3A1318" onclick="window.open(this.href);return false;)
Title: Re: 1974 CJ Starter motor problems
Post by: Fandango80 on April 14, 2009, 01:23:08 PM
Hi Guys,

Well, Finally got my original starter fixed.

40 Quid including new bushes, brushes, and a skimmed commutator. See my other post for a progress update if ya really bored. :roll:  

Cheers
Title: Re: 1974 CJ Starter motor problems
Post by: Ric Jacques on April 14, 2009, 07:07:44 PM
Nice one dude - glad your sorted.
Title: Re: 1974 CJ Starter motor problems
Post by: Bubba on April 15, 2009, 06:34:17 PM
cool =D>