Starting Problem - No Crank - Searched Threads
10-10-2006, 01:52 AM
#1
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Starting Problem - No Crank - Searched Threads
So I just want to make sure I came to the right conclusion...
83' SC. Usually driven about 25 miles at time, once a week or so. Drove it to my new place 275 miles away...with no issues. Got to destination, let idle for 2 minutes, and shut down. Went to start back up 5 minues later. Turned the key, got full instruments/lights on....turn to crank, and nothing. Engine didn't turn over, tho did heard a faint sound that sounds kinda like a power drill.
So from what I've read on other threads, the starter is dead due to heat soaking?
Just wanted to see if it's typical signs of the starter, or starter solenoid going bad???
The car roll/jump starts no problem, and drives great.
If it's the starter/solenoid, how easy is it to replace? I've worked on the 944 way more than the 911...kinda feel like I'm starting over here
83' SC. Usually driven about 25 miles at time, once a week or so. Drove it to my new place 275 miles away...with no issues. Got to destination, let idle for 2 minutes, and shut down. Went to start back up 5 minues later. Turned the key, got full instruments/lights on....turn to crank, and nothing. Engine didn't turn over, tho did heard a faint sound that sounds kinda like a power drill.
So from what I've read on other threads, the starter is dead due to heat soaking?
Just wanted to see if it's typical signs of the starter, or starter solenoid going bad???
The car roll/jump starts no problem, and drives great.
If it's the starter/solenoid, how easy is it to replace? I've worked on the 944 way more than the 911...kinda feel like I'm starting over here
10-10-2006, 03:23 AM
#2
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Chas:
Several things come to mind insituations like these and here are some components to examine very carefully:
1) Battery. Check cells, charge, and load test
2) Battery cables. Oxidation that effectlvely blocks 12v can be damned near invisible. Clean both battery terminals, and cables. Make sure the ground strap connection at the body is bright, shiny, and tight. Check both ends of the ground strap at the transmission mount-to-body for the same things.
3) Starter. You didn't say how many miles are on your car so its hard to tell if it at its end-of-life.
4) Ignition switch. The electrical half of this assembly is not a lifetime part and may have failed. Not expensive to replace.
Hope this helps,
Several things come to mind insituations like these and here are some components to examine very carefully:
1) Battery. Check cells, charge, and load test
2) Battery cables. Oxidation that effectlvely blocks 12v can be damned near invisible. Clean both battery terminals, and cables. Make sure the ground strap connection at the body is bright, shiny, and tight. Check both ends of the ground strap at the transmission mount-to-body for the same things.
3) Starter. You didn't say how many miles are on your car so its hard to tell if it at its end-of-life.
4) Ignition switch. The electrical half of this assembly is not a lifetime part and may have failed. Not expensive to replace.
Hope this helps,
10-10-2006, 06:57 AM
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Hi Chas,
The faint "power drill" sound you hear is probably the fuel pump,
you might also hear a high-pitched whining sound coming from
the CDI box (ignition box) in the engine bay.
My 83 SC had a problem with the same symptoms as yours,
Re-building the starter-motor and replacing the solenoid-cap
didn't help. In the end, I measured the voltage at the solenoid
while trying to start and found that it was only receiving 7 volts,
so around 5 volts was disappearing between the battery and
the starter solenoid. This is the circuit that goes from the battery
to the ignition switch behind the dash, then to the starter solenoid.
So, I went looking for points of high resistance along this circuit.
The problem turned out to be an after-market engine-immobilser
added by the PO, this introduced a relay and about 6 un-necissary
crimped spade-connectors, some with light-gauge wire,
between the ignition switch and the starter solenoid. I replaced
the mess of crimp connectors and light wire with heavier wire
and soldered all the connections.
Never had a problem starting since.
You can get to the starter solenoid contact by jacking up the
right rear wheel and reaching to the top of the starter motor.
My starter had an extra spade connection on the solenoid
terminal, which made a convenient test point. Measure the
voltage between here and earth (eg the transmission earth
strap)
Cheers,
Sam
The faint "power drill" sound you hear is probably the fuel pump,
you might also hear a high-pitched whining sound coming from
the CDI box (ignition box) in the engine bay.
My 83 SC had a problem with the same symptoms as yours,
Re-building the starter-motor and replacing the solenoid-cap
didn't help. In the end, I measured the voltage at the solenoid
while trying to start and found that it was only receiving 7 volts,
so around 5 volts was disappearing between the battery and
the starter solenoid. This is the circuit that goes from the battery
to the ignition switch behind the dash, then to the starter solenoid.
So, I went looking for points of high resistance along this circuit.
The problem turned out to be an after-market engine-immobilser
added by the PO, this introduced a relay and about 6 un-necissary
crimped spade-connectors, some with light-gauge wire,
between the ignition switch and the starter solenoid. I replaced
the mess of crimp connectors and light wire with heavier wire
and soldered all the connections.
Never had a problem starting since.
You can get to the starter solenoid contact by jacking up the
right rear wheel and reaching to the top of the starter motor.
My starter had an extra spade connection on the solenoid
terminal, which made a convenient test point. Measure the
voltage between here and earth (eg the transmission earth
strap)
Cheers,
Sam
Last edited by samoc; 10-10-2006 at 07:40 PM.
10-10-2006, 10:22 AM
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Thanks guys, a couple follow up questions:
Steve:
Do you think your #1 and #2 wouldn't be the case if I can roll start the car and drive it for an hour with no problem...
Car has 81k on the clock, so maybe the starter. As for your #4 issue, when I turn the key to start, something momentous definitely happens
Sam:
The power drill sound definitely is louder than the fuel pump sound...I know that sound well. Plus the fuel pump stays on when the key is in "run" position....this sound only comes about when I hold the key in the start position.
I'll check all the power connections today.
Any other ideas?
Thanks guys!
Steve:
Do you think your #1 and #2 wouldn't be the case if I can roll start the car and drive it for an hour with no problem...
Car has 81k on the clock, so maybe the starter. As for your #4 issue, when I turn the key to start, something momentous definitely happens
Sam:
The power drill sound definitely is louder than the fuel pump sound...I know that sound well. Plus the fuel pump stays on when the key is in "run" position....this sound only comes about when I hold the key in the start position.
I'll check all the power connections today.
Any other ideas?
Thanks guys!
10-10-2006, 07:56 PM
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Hi Chas,
Starting requires much more current than simply running the engine,
so you could could have steve's problem #1 or #2 and still be able to push
start and run fine. The amount of voltage lost through a bad connection
is equal to the reistance of the bad connection multiplied by the current
flowing through it (V = IR), so at very low currents, hardly any voltage is lost.
As you describe somthing "momentous" when you turn to "start", I'm guessing
that the solenoid is kicking in ok, so I'd concentrate on the main starter circuit.
This is a fat wire that runs all the way from the battery to the starter.
As steve says, check the connections on both ends and the earth straps.
This helped me:
http://www.pelicanparts.com/techarti...arter_diag.htm
More stuff here:
http://www.pelicanparts.com/911/911tech_articles.htm
Sam
Starting requires much more current than simply running the engine,
so you could could have steve's problem #1 or #2 and still be able to push
start and run fine. The amount of voltage lost through a bad connection
is equal to the reistance of the bad connection multiplied by the current
flowing through it (V = IR), so at very low currents, hardly any voltage is lost.
As you describe somthing "momentous" when you turn to "start", I'm guessing
that the solenoid is kicking in ok, so I'd concentrate on the main starter circuit.
This is a fat wire that runs all the way from the battery to the starter.
As steve says, check the connections on both ends and the earth straps.
This helped me:
http://www.pelicanparts.com/techarti...arter_diag.htm
More stuff here:
http://www.pelicanparts.com/911/911tech_articles.htm
Sam
10-10-2006, 08:13 PM
#6
Rennlist Member
Chas: After you get the starter issue fixed repair the wiring circuit for the fuel pump. That puppy is NOT supposed to run until the car cranks!
Pete
Pete
