Posted By |
Discussion Topic:
Flathead turns over slow on starter
-- page:
1
2
|
|
ole_Bill |
04-14-2011 @ 5:47 PM
|
|
|
New Member
Posts: 165
Joined: Dec 2009
|
I had the all the plugs removed from my newly rebuilt flathead and spun it up on the starter to ensure I had good oil pressure. No problem. Now I have the engine reassembled and ready to run but the starter turns it too slow to start. It has a new 6V Optima battery, fully charged. I think this means I have a ground problem somewhere.....right? Where should I look? Any other posibilities?
|
supereal |
04-14-2011 @ 7:01 PM
|
|
|
Senior
Posts: 6819
Joined: Oct 2009
|
If the engine turned over without problems until the plugs were installed, the battery may have been depleted. Put a voltmeter across the battery and see what the voltage reads when the starter is tried. If the reading is below 4-4.5 volts, either the battery is low, or there is a big voltage drop between the battery and the starter. Put the voltmeter between the starter input terminal and the solenoid end of the cable and push the starter button. The reading on the meter will tell you if ther ia a loss, and how much. Do this to each leg of the circuit, and also be teen the engine block and the ground side of the battery. When checking, always put the probe directly on the battery terminal and not the cable clamp. If this test doesn't show where the power is being lost, i' d suspect the starter, itself.
This message was edited by supereal on 4-14-11 @ 7:04 PM
|
TomO |
04-15-2011 @ 4:45 PM
|
|
|
Senior
Posts: 7256
Joined: Oct 2009
|
Check that the oil pan mounting surface for the starter is not painted and that the starter is not painted on its mounting surface.
Tom
|
Norm |
04-15-2011 @ 5:22 PM
|
|
|
Member
Posts: 85
Joined: Oct 2009
|
Make sure that the battery cables are large enough. The last time I saw this behavior the car had 12V battery cables - not enough copper.
|
trjford8 |
04-15-2011 @ 8:24 PM
|
|
|
Senior
Posts: 4228
Joined: Oct 2009
|
Make sure the battery is fully charged and follow the advice others have given you. The size of the battery cables is critical along with good grounding.
|
ole_Bill |
04-16-2011 @ 7:14 AM
|
|
|
New Member
Posts: 165
Joined: Dec 2009
|
The cables are all new and they are the correct size for a 6V system. I'm checking grounds today. Lord, I hope I don't have to pull that starter (again).
|
TomO |
04-16-2011 @ 9:09 AM
|
|
|
Senior
Posts: 7256
Joined: Oct 2009
|
Bill, if you are sure that the starter mounting surfaces do not have paint, you can check out the grounding circuit using the same procedure that Supereal gave you to check out the NEG (supply) side of the circuit. I would check out the NEG circuit first as defective cables or solenoid will drop considerable voltage. Even new cables can drop 1/2 Volt or more.
Tom
|
drkbp |
04-16-2011 @ 6:47 PM
|
|
|
New Member
Posts: 180
Joined: Aug 2010
|
ole_Bill, What model? Or did I miss it? Ken in Texas
|
Dipper005 |
04-20-2011 @ 7:50 AM
|
|
|
Member
Posts: 12
Joined: Nov 2009
|
Hi. Does your starter make a clicking noise when it's trying to turn the engine over?
|
ole_Bill |
04-25-2011 @ 6:06 PM
|
|
|
New Member
Posts: 165
Joined: Dec 2009
|
Today I pulled the starter and took it to Chattanooga Alternator & Generator to be checked. They confirmed that nothing is wrong with the starter. Before I reinstalled it I thoroughly wirebrushed all mating surfaces so there is no paint, no rust. I think I detected a slight improvement, but the motor still turns too slow to start. I'm thinkung about trying a 12V battery. Can I hook it directly to the battery without damaging anything else on the car or do I have to isolate the starter before spinning it on 12V? Before I do anything else I'm gonna check out the voltage drop issue. Tomorrow.
This message was edited by ole_Bill on 4-25-11 @ 6:08 PM
|