Starter Playing Up

[Billy Smalls]

Hi - battery is fully charged but went to start the other day, after driving it 12 hours before and nothing happened!! Like I said, plenty of charge...

gave the starter a few sharp blows with a small hammer and it was more inclined to turn. It's an auto, so thought it might have been the inhibitor switch, but that wasn't the case either...

Done it a few more times since - is the starter on the way out or do they just failed never to return?

I see one can buy just the solenoid 'end' - so maybe that's it???

never worked on a starter before???

Thanks for any advice

[123GT-AMAZON]

Originally Posted by Billy Smalls

Hi - battery is fully charged but went to start the other day, after driving it 12 hours before and nothing happened!! Like I said, plenty of charge...

gave the starter a few sharp blows with a small hammer and it was more inclined to turn. It's an auto, so thought it might have been the inhibitor switch, but that wasn't the case either...

Done it a few more times since - is the starter on the way out or do they just failed never to return?

I see one can buy just the solenoid 'end' - so maybe that's it???

never worked on a starter before???

Thanks for any advice

Hi ya , sounds like a sticky solenoid in starter , you can also have yours rebuilt so look into that if the one you can buy is pricey ...

Kimd regards
Robert.w

[Derek UK]

Make sure that the earth lead that runs from the bell housing to the chassis leg is clean and secure. It's on the opposite side to the starter. Also check the braided earth lead where it bolts to the bulkhead. If the braiding has been attacked by acid they can be very frail and not work as they should. Replace if that is the case.
You can do a quick check by running a jump lead from the battery earth with the other end well clamped to the engine.
Clean up the battery posts and clamps. Lightly file or scrape if needed. A light smear of Vaseline is good.

I doubt if you have one, but the later slim line 700/900 style starters should never be hit with a hammer. The field coils are bonded to the case, the reason they are smaller, and they can drop off if the case is bashed.

[Volvo_133]

When the key is turned to start position, do you hear a click. (this is the solenoid energising.
Do the earthing checks as Derek has suggested. The small cable (the only one) on the solenoid is responsible for energising the solenoid and is a push on lug type connection. Ensure this is clean and is a secure connection. If you do not hear the click in start position then your solenoid is at fault.

[Billy Smalls]

Thanks to you all for your advice. I shall check the connections, clean and vaseline as necessary.

No, I don't hear a click when I turn the ignition on (but don't start) so i reckon the solenoid is on the way out....are they serviceable??

Thanks again and Merry Christmas!!

[Ron Kwas]

Billy;

You wouldn't expect to hear a click other than at the Ign Sw when turning ON the Ign Sw (Pos 3)...the only time Solenoid should show any signs of life is when turning key to Start position (4), or better yet pushing Momentary Start Button! That's when it gets power applied and activates...and that in-turn applies power to Starter Motor, which automatically engages Flywheel and turns over engine...

Clarification: "Starter" is the common term for the Solenoid and DC Motor assembly. (The reason I must mention this is because on some vehicles like Ford, these components are not one assembly, but separated!) When it fails to function as expected, it is good to troubleshooting the assembly by the Divide and Conquer method!

Solenoid(Sol): Its function, as a High Current Contactor (HCC), is to pass power through to DCMotor itself...so when activating it (either by turning Key to the Start position or better yet, pushing Start Button after turning ON Ign with Key) we would expect it to at least audibly KLACK! ...but we probably wont even hear that because if it passes power through to DCMotor as it should, that will turn over engine, which makes a lot more noise and which is what we will hear...if everything goes as expected...

DCMotor: It's function is to turn (with authority, which requires high current*, therefore power must be switched by a HCC), as power is applied, and by way of the bendix coupling, engage the Flywheel Ring Gear to turn the Engine over. If it does not turn when Solenoid is activated, one of two fault conditions can exist:

1. Power is not being applied through High Current Contacts (HCC). [This may be because of a worn or carbonized contacts, or other Sol issue...they are serviceable but this requires special equipment and techniques.] Or

2. Power is being applied and DCM is not turning [If power is being applied should be verified by checking for voltage at the output of Sol, when Sol is activated - Output terminal is the lower stud to which small hop-over heavy cable into DCM connects.]

Striking the DCMotor with a hammer to shock it out of a "dead-spot" is hold-over technique from Lucas equipment, where such action is known to often help...it is quite rare for such an action to help on Bosch equipment, and in-fact extremely BAAAAD, and absolutely VERBOTEN(!) if Starter Assy has been replaced with a more modern Perm Mag DCM, where such a strike may demag the PMs and render the Starter into an anchor for small water craft!!

* Note: If DCM fails to be supplied by a good power source (read stiff voltage source), which is not collapsing from a poor Battery State of Charge, or Voltage Drop somewhere along the current path, it may not have the authority to turn over engine (or even to continue to hold the Sol pulled in, resulting in "Cyclic Klacking" to coin a possibly new descriptive). This is where while troubleshooting, one must remember which comes first...and that is power from the Battery!

Reference:
Source: http://www.sw-em.com/starter.htm

Finally, use ACZP instead of Vaseline!

Good Hunting!

[Billy Smalls]

Originally Posted by Ron Kwas

Billy;

You wouldn't expect to hear a click other than at the Ign Sw when turning ON the Ign Sw (Pos 3)...the only time Solenoid should show any signs of life is when turning key to Start position (4), or better yet pushing Momentary Start Button! That's when it gets power applied and activates...and that in-turn applies power to Starter Motor, which automatically engages Flywheel and turns over engine...

Clarification: "Starter" is the common term for the Solenoid and DC Motor assembly. (The reason I must mention this is because on some vehicles like Ford, these components are not one assembly, but separated!) When it fails to function as expected, it is good to troubleshooting the assembly by the Divide and Conquer method!

Solenoid(Sol): Its function, as a High Current Contactor (HCC), is to pass power through to DCMotor itself...so when activating it (either by turning Key to the Start position or better yet, pushing Start Button after turning ON Ign with Key) we would expect it to at least audibly KLACK! ...but we probably wont even hear that because if it passes power through to DCMotor as it should, that will turn over engine, which makes a lot more noise and which is what we will hear...if everything goes as expected...

DCMotor: It's function is to turn (with authority, which requires high current*, therefore power must be switched by a HCC), as power is applied, and by way of the bendix coupling, engage the Flywheel Ring Gear to turn the Engine over. If it does not turn when Solenoid is activated, one of two fault conditions can exist:

1. Power is not being applied through High Current Contacts (HCC). [This may be because of a worn or carbonized contacts, or other Sol issue...they are serviceable but this requires special equipment and techniques.] Or

2. Power is being applied and DCM is not turning [If power is being applied should be verified by checking for voltage at the output of Sol, when Sol is activated - Output terminal is the lower stud to which small hop-over heavy cable into DCM connects.]

Striking the DCMotor with a hammer to shock it out of a "dead-spot" is hold-over technique from Lucas equipment, where such action is known to often help...it is quite rare for such an action to help on Bosch equipment, and in-fact extremely BAAAAD, and absolutely VERBOTEN(!) if Starter Assy has been replaced with a more modern Perm Mag DCM, where such a strike may demag the PMs and render the Starter into an anchor for small water craft!!

* Note: If DCM fails to be supplied by a good power source (read stiff voltage source), which is not collapsing from a poor Battery State of Charge, or Voltage Drop somewhere along the current path, it may not have the authority to turn over engine (or even to continue to hold the Sol pulled in, resulting in "Cyclic Klacking" to coin a possibly new descriptive). This is where while troubleshooting, one must remember which comes first...and that is power from the Battery!

Reference:
Source: http://www.sw-em.com/starter.htm

Finally, use ACZP instead of Vaseline!

Good Hunting!

Hi Ron - wow, you are a physicist yeah? I struggle with Physics so will have to read your post when I'm a little more awake. Ironically I work with the Quantum Photonics Team at University of Bristol....!! Thanks for your help...

[SwallownAmazon]

Might be just worn brushes in the starter motor.
We are very fortunate in West Kent, we have a small business called Curd Brothers in Tunbridge Wells who rebuild starters, dynamos, alternators, etc. Old fashioned good bloke service and very reasonable.