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Starter problem and motor wont shut down

hondo402000

Darth Vader
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Ok I installed a new gear reduction starter, new battery pos and neg cable, the starter acts like the battery has a low charge but I know the battery is fully charged, when I start the car the starter turns slow. I then cleaned the ground comming from the motor to the body and cleaned the battery ground to motor, the starter acts better but not like it use to. the only other problem I am having is I pulled the dash off to refinish and pulled the heater box to replace it and after putting every thing back together the car will not shut down when the Ignition is switched off unless I put the turn signal on at the same time. I know I need to pull the dash out again and look for a loose ground wire or loose wire, UGG could the starter problem be associated with the motor not shutting down when switched off?
 
hondo402000 said:
could the starter problem be associated with the motor not shutting down when switched off?
Seems unlikely to me. Obviously the starter solenoid is getting enough juice to engage the starter (which for those gear drive things is quite a bit); and power to the solenoid is the only thing that happens inside the cabin. The only parts in common between the two circuits would be the battery cables and the ground strap to the engine. And if the ground strap were bad enough to cause a problem with the ignition, I don't think the starter would work at all.

My suggestion would be to pull a side wire off the coil, and connect a voltmeter directly to the starter terminal and the starter housing. Then jumper the side terminal on the solenoid to the battery terminal to crank the engine, and see how much voltage the starter motor is actually getting. If it's at least 10v and the engine is still cranking very slowly, most likely the starter motor itself has a problem (broken wire, stuck brush, binding gears, etc.)

Or, if you don't have a voltmeter, just pull the wire and crank the motor for 30 seconds or so, then feel all along all the battery cables and ground strap to the engine. If you find a hot spot, that's where the problem is. No hot spot means most likely a bad battery, or a bad starter.

Yeah, I know it's new, but these days new doesn't always mean good. One other thought, is there any chance you got the wrong model of starter ? I think (not certain) that the TR4 starter had a bigger pinion gear but the same bolt centers as the TR6. It might engage but bind ?

BTW, it's possible for battery cables (and wires in general) to corrode or break under the insulation, such that they will no longer carry current as they should but look OK from the outside. Not a common problem, but very frustrating to find when it does happen.

The ignition problem doesn't sound like a bad connection or bad ground to me; but rather something bleeding current into the ignition circuit with the key turned off (possibly the ignition switch itself).
 
This is the kind of crap that happens to me. "Oh I think I will upgrade my starter" then wamy.
 
If your old starter was not dead the obvious thing this amatuer Tinster would try is to swap the old one back in and see where that gets you, but if it is dead.....
 
I think I got my new starter from doc Matin and I did have the original starter rebuilt and its in a box, the guy who rebuilt the original said is checked out ok and he did replace the solanoid, (sp) well I thought about putting the org, starter back on anyway it seem to really spin the motor a lot faster, so if the weather holds out I will do that tomorrow, but since I am in to pyrotechnics now I have a few rockets to build too. ps I did install a new Ig switch, and its a new battery, and I guess just because its new doesnt mean it works,,,,,,,
 
If I understood correctly that you have a gear reduction starter that spins the motor slower than the regular starter, then there is a problem with it. No doubt in my mind.
 
as for the ignition problem, maybe you have the wrong lamp in one of your turn signal sockets? I read somewhere that wrong lamps can cause this problem.
 
This from a saab related forum.....


Bulbs being wrong cause starting issues etc....

Be very careful when replacing bulbs in the turn signals and taillights. We have seen issues when people install multi filament bulbs in single filament bulb sockets and visa-versa. One of the issues that we have seen is that the vehicle will run on when turning the ignition off or will not start at all. Keep in mind that different symptoms could occur with different cars. This may or may not apply to your particular Saab.

this is the reference I was thinking of...
 
I would sure like to know the theory behind that !
 
Yes I am interested in that theory too, when the run on problem started I went through everything I could think of, and turning on a signal would cut the engine, pulling the bulb out of the Ignigtion light would cut the engine, but turning on the lights would not work so it is associated to a circuit but for now I just got use to putting on a left turn to get the engine to quit but then every once in a while I turn the key off and the engine quits.... go figure but I will swap the starters out soon,,,, maybe thats the problem with the run on??
 
You know, something about this post caught my eye last night. This past spring, another owner posted a similar problem and potential fix here. He did get his corrected, but I can't remember the complete answer, but Randall, everyone had the same reaction as you, including me.

I've got to dig through some old bookmark files, because it was so odd, that I'm almost positive that I created a link to it.
 
hondo402000 said:
pulling the bulb out of the Ignigtion light would cut the engine
You don't by any chance have an MSD box or similar for the ignition, do you ?

That's a known problem with the "high power" ignitions that draw current directly from the battery. Since they draw only a little power from the ignition circuit, anything that bleeds current back into that circuit (like the ignition light when the engine is still turning) can fool them into thinking the key is still on.

The MSD 6 comes with a diode to install into the ignition light circuit to prevent the problem.

But the stock points & coil should draw more current than will pass through the ignition light, so it usually shouldn't happen ... unless perhaps you've put in a much higher power bulb for the warning lamp.
 
Yes philman my daily driver is a Saab 9000 and that makes total sense to me. What forum did you find that on? Anyways, I am in the middle of an electrical problem on my Saab and I cannot figure out if it is the crank shaft sensor, the direct ignition, wiring harness, or the ECU, so I came back to the British forum where the technology is beautifully simple.
Sp53
 
Yes philman my daily driver is a Saab 9000 and that makes total sense to me. What forum did you find that on? Anyways, I am in the middle of an electrical problem on my Saab and I cannot figure out if it is the crank shaft sensor, the direct ignition, wiring harness, or the ECU, so I came back to the British forum where the technology is beautifully simple.
Sp53
 
Hondo,
I have an MSD6 unit in my TR3 and have used them in other cars.
Do you have the diode in place as noted in the directions (I suspect you do)?
I've never had starter run on but without the diode the car won't shut down due to the small amount of elec running to the generator light. That's where the diode is placed in line to make it a one way circuit.
If the old original starter worked properly it could be a faulty new unit.
 
hondo402000 said:
yep I have a MSD 6 unit,
OH. Then you need to install the diode. If you don't have the one that came with the MSD, run down to Radio Shack and buy one. Any "general purpose" or "rectifier" diode with ratings of at least 100 volts and 1 amp should do just fine; but one of the axial-leaded units (eg 1N4002) will probably be easier to work with. It needs to be spliced into one of the wires to the ignition lamp. I put mine between the ignition switch and the lamp, since that was easier for me, but it could also go between the lamp & the alternator/generator.

If the diode is marked with a band to indicate the cathode, the band needs to go on the side towards the alternator (or lamp if you put it on the high side like I did). If it's marked with an arrow, the arrow should point towards the alternator.
 
I had this problem last year with a solenoid (sp?) i replaced on my '76 tr6. I disconnected the wire that goes to the dist. from the starter side (ie= removed one of the two small wires) and everything has been just fine since. I still don't know why.
 
I never saw the part about the diode but I went to the mallory site and they said the same thing so off to radio shack for a diode and I will let you know what happens

thanks
 
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