No starter cranking
Thread Starter
Racer
Joined: Sep 2008
Posts: 403
Likes: 7
From: Space Coast Florida
No starter cranking
I have a 74 350 auto. I've checked negative grounds from battery (needed replaced) and from frame to starter solenoid (also bad) and thought that would solve the problem. But it did not. If you try to crank it there's not signs of power to the starter. Tried tapping on solenoid and it did show some limited life although it was short lived.
My question is what could be the problem and how do I fix it? The bat is good still, the negatives are grounded, but still not getting any response. If it is a bad solenoid how can I test other then banging on it? Any and all info is appreciated.
My question is what could be the problem and how do I fix it? The bat is good still, the negatives are grounded, but still not getting any response. If it is a bad solenoid how can I test other then banging on it? Any and all info is appreciated.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
Your problem is most likely a bad 'neutral start switch' (which prevents 12v signal from getting to the solenoid unless it is in neutral...bad switch/no go) or a bad starter solenoid. The test for either is to see where the 12 v signal to the solenoid gets 'lost'. If 12v doesn't get to the solenoid, it won't be sent to the starter (bad NSS); if 12v does get to the solenoid, but isn't passed to the starter, you have a bad solenoid; if 12v gets to the starter but it doesn't turn, you have a bad starter.
Thread Starter
Racer
Joined: Sep 2008
Posts: 403
Likes: 7
From: Space Coast Florida
Your problem is most likely a bad 'neutral start switch' (which prevents 12v signal from getting to the solenoid unless it is in neutral...bad switch/no go) or a bad starter solenoid. The test for either is to see where the 12 v signal to the solenoid gets 'lost'. If 12v doesn't get to the solenoid, it won't be sent to the starter (bad NSS); if 12v does get to the solenoid, but isn't passed to the starter, you have a bad solenoid; if 12v gets to the starter but it doesn't turn, you have a bad starter.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
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From: Hinckley OH
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Thread Starter
Racer
Joined: Sep 2008
Posts: 403
Likes: 7
From: Space Coast Florida
Ok, so the 12 volt has reached the solenoid, but how do I check if it reaches the starter? I can tap the starter itself and it gives me some pretty disgusting growns for a second and dies. Can this still be the solenoid? It seems like since I'm tapping the starter and it kicks a little that it is getting power from the solenoid.
I think I'm just going to replace both of them. The fuel pump and the tranny also need some leak fixing as well. Tranny had not fluid and got gas in my eye yesterday, its fun working under a 36 year old car..
I think I'm just going to replace both of them. The fuel pump and the tranny also need some leak fixing as well. Tranny had not fluid and got gas in my eye yesterday, its fun working under a 36 year old car..
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
If you are getting groans from the starter when the solenoid kicks in, then 12v is getting sent to the starter....but there may be very little current carrying capability from the solenoid, depending on the condition of the contactor disk and contacts. That voltage is sent to the starter via those metal strips that stick out of the starter housing and bolt up to the solenoid.
At this point, what you need to do is to use a set of jumper cables to 'put the juice' to your starter (from another battery that you know to be good). Hook the negative to the grounding strap terminal lug or bolt [or to a clean place on the frame] and the positive to that lug on the solenoid where 12 volts gets sent to the starter (being careful to be certain that the positive clamp does not get shorted to ground). Hook the cables to your starter/solenoid first, then hook the negative cable to the 'feeder' battery...then just touch (solidly, not lightly) the positive cable clamp to the positive battery lug. That will cause the starter to turn as expected IF the starter is OK. If it just groans like before, the solenoid is your problem.
P.S. If you have a battery disconnect on your C3, put it in disconnect mode so the C3 battery is not involved in the test.
{You are certain that you don't have a bad battery....right?}
At this point, what you need to do is to use a set of jumper cables to 'put the juice' to your starter (from another battery that you know to be good). Hook the negative to the grounding strap terminal lug or bolt [or to a clean place on the frame] and the positive to that lug on the solenoid where 12 volts gets sent to the starter (being careful to be certain that the positive clamp does not get shorted to ground). Hook the cables to your starter/solenoid first, then hook the negative cable to the 'feeder' battery...then just touch (solidly, not lightly) the positive cable clamp to the positive battery lug. That will cause the starter to turn as expected IF the starter is OK. If it just groans like before, the solenoid is your problem.
P.S. If you have a battery disconnect on your C3, put it in disconnect mode so the C3 battery is not involved in the test.
{You are certain that you don't have a bad battery....right?}
Thread Starter
Racer
Joined: Sep 2008
Posts: 403
Likes: 7
From: Space Coast Florida
As best as I can determine the battery is in good condition. I tried a load tester on it, my battery charger has a volt tester that I tried, and it won't charge up any more. It's possible that these test where faulty but they all seem pretty reliable. The voltameter said above 10v as well. So if worse comes to worse I can take it to advance to get tested I guess, but I think the bat is good.
As for the test, I will try that and I'm curious to see the results. Thanks I'll keep you posted.
As for the test, I will try that and I'm curious to see the results. Thanks I'll keep you posted.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
10 volts is not sufficient to start the engine. I think you just have a bad battery. A very weak battery will still indicate that it is charged. But it won't take long to get charged and it will be drained almost instantaneously when you connect a high load to it.
Thread Starter
Racer
Joined: Sep 2008
Posts: 403
Likes: 7
From: Space Coast Florida
My voltameter has settings for 10V and 50V scales. So the closest I can get is 10V. It showed full 10V and slightly above 10V when set to 50V scale. So I can assume its slightly above 10. Unaware of how much above or how much it gets to ten. So what I'm saying is that it very well could be a bad bat. I'm going to use one that I know is good how ever and try the direct test to make sure. Thanks for the heads up though.
Thread Starter
Racer
Joined: Sep 2008
Posts: 403
Likes: 7
From: Space Coast Florida
Ok, did the battery to the solenoid hook up. Brand new bat, less then a month old. What resulted from this was the same as from the regular set up but with more grinding from the starter. Think I'm looking at a bad solenoid. Should be fun to get off with headers in the way. Thanks for the help!
