924Board.org

[924guy]

Before i take a sledge hammer to this thing...

okay, heres the situation:

several months ago I had my 78 running no problem, after eight years sitting... since then the battery died. i replaced the battery, and the starter no longer even turns. now its been little awhile since i started her, so ive gone through grounds and connections, check continuity, all seems okay.
ive got 1.6 ohms at the coil, continuity between the distributer and the bosch box *2 yellow wires), 13.6 v at the starter main lug.
I pulled the starter and bench tested it, it spun. I put it back in, checked the connections at the alternater and have 13.6 v at the feed to the starter. i have continuity at the ballast resistors, and positive volts with the key in the on position. i tried to jump the starter by applying battery directly to the single wire (small) lug of the starter, it spun, but the solenoid did not engage and push the gear into the flywheel.
I do hear a click with the key at full turn, sounds like the coil, but im not sure, working on it solo and didnt want to recruit help until i have a better idea of what i need to do. its driving me up the wall...

im missing something, what is it?

any help is appreciated... i thought i had a step by step but cant find it....

on the up side, i have brakes again, and besides an alignment the five lug swap is complete....
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[Smoothie]

Sounds like it might be the olde corroded cable/s between batt/alt and starter syndrome. Were they ever replaced?
(It's possible for weak wiring to pass a good-looking voltage level during tests, but fail to deliver the required amps when "under load" in actual use.)
_________________
"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[924guy]

Good point! , the cables have been replaced, but i think it was back in 98 or so. I guess its time to build a new harness (again.) Good place to start anyhow... thanks Smoothie...
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[Slam]

How about removing the starter solenoid and cleaning and lubing the piston in it? They get quite gummed up and then bind, but are easily refreshed. I use a very, very small film of white grease on reassembly. Given your list of tests and symptoms, this may help.
_________________
'84 944 - kid blew motor
'83 944 - resting comfortably. For 12 years
'87 944 - sideswiped by trucker
'80 924 - gone
'78 924 - gone
'77 924 - rusting comfortably

[owenexile]

I think i can help!! I had exactly the same problem. take ure starter out and test it. Say with the first test , let the solonoid be closest to u, Laying down. Second test is to let the solonoid roll over and be futher away from u as the starter.

I found doing that the starter will work on the first test but as soon as i turn it over for the second test it doenst kick-in.
Which made it so frustrating i toke the starter out about 8 times before realising the solonoid didnt make contact with the bushings inside it, If it was on a diffrent angle from how i tested it ( i presume its got bushings inside it)
_________________
924 1982 N/A
For some reason theres always a earth problem somewhere with this car...

[fiat22turbo]

http://garage.ideola.com/prod-HiTorque.html
_________________
Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[924guy]

love the lightweight super mini starters, but lol\d , as this is the challenge car, its just not in the budget. maybe when i get the 931 back together though...

I think the plan at this point is to pull the starter again, and take it down and have it load tested, and rebuild the starter and alternator harness. I also need to find my spare ignition control unit and figure out how to test output on it. Im just going to begin at the starter and work backwards from there until i find the issue.

if anyone has more ideas, please feel free to post them up, but at the moment im stuck until i can verify the starter conditon. the alternator has already been rebuilt, being a Bosch/Rhone hybrid and has good 13v pass through at the regulator, so i think thats okay and not bleeding power.
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[morghen]

dont know if was mentioned before..dont have the time to read all...

there is a thick but very short (1inch) grounding cable between the coil and the case of the starter(it goes trough the case right to the rotor i think)...that usually is a very coroded cable.
_________________
Supercharger and EFI kits
https://www.the924.com

[Smoothie]

+1^
I had to replace that wire on one of my starters.
2 pics starting here <click>


Also, while the starter's out, chase the large threads in the starter mounting flange, block, bolts, nut with taps/dies, and clean the mounting surface where the starter makes contact with the block. -Because the starter's grounded through its' mounting.

-Also, a click but no starter spin can be caused by a ruined solenoid (internally rusted). Obviously a new solenoid fixes that.
Absence of even the click can mean dirty, gunked-up solenoid piston (armature), and just a disassembly and cleaning fixes that.
_________________
"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[D Hook]

[924guy]

well, I spent a little time yesterday and pulled the start and ignition harness. The three point connector just below, and in front of the battery that leads down to the starter and alternator had a very fried wire. the insulation was decayed beyond saving and the "blue" wire was eaten up almost completely through.







I rebuilt the harness using scavenged wiring and shielding from my 944 parts car. double layered the shielding using the stock plastic shrink type stuff from the 944 and covered that with split loom. Replaced the contacts in the connector as well, with a little luck this will hold out another ten years...



Still no start. starter will be load tested today, i suspect a bad solenoid but didnt mess with it at all yet. once thats confirmed ill probably try to disassemble and clean it up first. failing that ill be looking to replace the solenoid or complete assembly.
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[924guy]

A friend took the starter for me and load tested it at two different auto parts stores, both said the solenoid is shot, but he also said neither place had anybody with any real knowledge of what they were doing. But that goes along with my prior conclusion, so im good with it. Im going to inspect the internals of the unit, and see if i cant get away with a good clean up before i start looking for a replacement. under normal circumstances id just have a shop rebuild the whole unit, but this is a low budget challenge project, so its DIY on everything possible

i found this thread at vortex for some guidance, its interesting..
.
http://forums.vwvortex.com/showthread.php?2359900
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[924guy]

the upside is i disassembled my solenoid and the piston was stuck. a little clean up work and all good now. engages and everything. before it put the whole unit back in , i need to figure out the following ...

please explain to me what term 15a (16 in haynes) does, if its an input or output voltage and how i should be able to test it. when i apply volts to it, it does nothing. when i apply 12v to term 50, i get a few volts out of it while the starter clutch is engaged. im confused.



thanks...
_________________
Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

[Harm]

Thanks for the guidance thread link: Just what I needed! I'm (re)building another engine on the
enginestand and the/my old starter might come in handy to check if oil pressure is being accomplished etc.

15....12V+ at both ignition on and start
I'm no electrics guru but if I'm not mistaken this allows more power to/through the ignition coil and
transistor ignition unit while cranking, at the earlier cars ignition (<81)?
So, more spark power at start.
An electrics guru should be able to determine the direction.
My guess is its input since the starter is ground, completing the flow when starting.
(Strap an extra ground-cable between the engine and the firewall to help the flow return to the battery)

Regards, Harm.
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Porsche 924 NA 1982 LY7A/A3A3 _ Greater driving pleasure never harmed anyone.

[Smoothie]

+1^
That rectangle with 2 diagonal lines shown as part of the starter represents the solenoids' electromagnet. When the ignition switch is turned to "start", 12v+ passes to-through solenoid terminal 50 activating the electromagnet. This pulls both solenoid switches closed (they're shown as opened in the diagram - one at each side of the electromagnet (attached to terminals 30 and 15a)). When pulled-in, 12v+ passes from the battery through solenoid circuit 30 to power the starter motor, and it also flows out through circuit 15a to the ignition coil to bump up the voltage there during starting.
_________________
"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox