Slow crank, warm temperatures.

[Big Bird]

I have been having an issue of late with the starter cranking the motor over really slow, almost to slow to start. The batteries have tested good (700 CCA). Amp draw when glow plugs are energized is about 85 amps, and when starting is about 750 amps. Bot of these were checked with a clamp on dc amp probe on the positive cable.

Is the starting amp draw high?

[Big Bird]

oops, I guess I should have put this in the obs section... If you all have any suggestions just let me know...

[BIG JOE]

Battery connections... These powerstruggles need excellent battery connections to turn over properly.. I like to take a porting bit and go around my battery terminals and clean them every other day..

[Big Bird]

oh yeah, forgot to mention I have cleaned up the terminals, no voltage drop there even when cranking.

[Highwaywrench]

Dude, if you are seeing 750 amp draw while cranking, replace your starter, it is DONE.

I just did mine the other day, it was drawing 675 at cold start, and wouldn't even start the truck once it warmed up. It has been dragging more and more, and finally, that was it.

The new one whirls over like nothing. Now if I could do something about the rest of the engine....

[jesilvas]

Batts should be up to about 825+ CCAs if I'm not mistaken

[fordmasterdieseltech]

yeah you should have 2 850cca in there for problem free starting. but regaurdless that kind of amperage draw from that starter is excessive. replace starter and recheck operation.

[Big Bird]

as far as the batteries go, they are 700 CCA batteries that are in the truck, have been since I got it in 07. They have worked just fine until this problem, but they still check out fine.