Slow Cranking IDi

[Spun4Fun]

Slow Cranking/Spin over IDi

The day after i finished installing a large Tranny cooler out of the blue the truck developed slow spin over or cranking / delay before it fires right up , the truck use to fire up super fast in the past . I though Battery issue and sure one was bad so i got it replaced and that did not help , SO i went back to the battery shop and got 2 Brand new 850cc batteries and installed them but that did not help still slow turning / cranking , This issue happen on a cold , warm or hot engine even after i drove 500 miles and shut it off or park it over night , so the IP probably out of the picture Here is few things been done to the truck to narrow it down :

New glow Plugs about 2 month ago , the WTS relay cycle , Filter is full of diesel as i thought i lost the prime , no air intrusion that i can see , the battery cable resistance test show .2 ohms across the red lead from one end all the way to the starter and same on the negative cable . I cleaned all the terminal by the starter which is the OEM starter from what i can see .


What else could it be ..???,Is the starter on its way out . Auto zone claim that they can test the starter on the truck by hocking up one of their tester .. ! is that a valid test . One more thing to mention that this starter had seen some Oil soak in the past during the time i was hunting the source of the oil leak

 

[icanfixall]

Yes is the short answer about testing the starter in the truck but.. You need a tester that fits over the cable going to the starter. then start cranking the engine to determine the amps draw. Sorry I can't tell you what a good or bad amp draw a starter pulls. My guess is your original starter is failing. The oil mess on the starter really is no harm but its not a good thing either.

 

[ironworker40]

Clean and tighten ground wires to engine block and frame on front of engine. If starter is oil soaked it could be the starter or may have a bad ground from starter case to engine but I doubt it.

 

[madpogue]

You've eliminated pretty-much everything except the starter, and possibly the battery negatives.

 

[Spun4Fun]

One thing i need to check that just came across my mind is Voltage Drop Testing from the battery post to the starter for both the - & + leads

 

[Spun4Fun]

Clean and tighten ground wires to engine block and frame on front of engine. If starter is oil soaked it could be the starter or may have a bad ground from starter case to engine but I doubt it.

Every thing been cleaned real well and tighten pretty snug

 

[sassyrel]

how much corrosion,,,or is the hot cable,,on the right battery, oversized bit?? meaning corrosion inside of that cable?? they are notorious for this,,and that could eat at the cable really quick...

 

[Spun4Fun]

how much corrosion,,,or is the hot cable,,on the right battery, oversized bit?? meaning corrosion inside of that cable?? they are notorious for this,,and that could eat at the cable really quick...

Zero corrosion that i can see without stripping the jacket of the big wires but they passed resistance test and non of them are swollen , However i am going to do the voltage droop testing on both the - and +

 

[OLDBULL8]

Smack the damn thing on the bottom with a BFH, some times the brushes get stuck and make a very light contact, causes a lot of arching, starter don't get get the full voltage. Worth a try, don't cost nothing. A lot of starting with brushes like that, heats up the brush springs, makes them weak.

 

[tbrumm]

I would bet the starter is getting tired as you have pretty much eliminated everything else. A person doesn't realize how much the starter is slowing down as time goes on. But put a new one in and then you really see how slow the old one had become. My original starter had gotten oil soaked and what a mess I found inside it when I took it apart.

 

[Spun4Fun]

Well voltage droop testing on both the - and + passed reading between .4-.3 DCV when i turn the key to start . So i asked my son to start it after to the WTS light cycle . As i was watching and waiting i couldn't help it but to notice the GP relay was making a strange buzzing sound and some smoke was coming from under it's cover like wires burning . the thing was so hot to the touch . I removed almost melted electric tape was covering the Big red cable and we gave it a try ( No smoke this time ) she fired right up )

Not sure if i found the culprit or it's another 7.3 IDi spin/mystery to just get my head in the wrong direction . I am planing to take the wires from the relay and clean them pretty well . the true test is when i go back and try to start it latter today and see if it fires right up

 

[Clb]

Overall condition of the pos. leads and terminals also contribute alot to weak current flow.
Look for corosion at cable to lug/batt. Clamp also.

 

[abepratt]

Mine was doing the same thing even after I replaced the starter. I tried new batterys and everything, just let it go for a while. Finally got fed up with it and it ended up being they had gave me a bad starter. Oh well they swapped it for free

 

[Spun4Fun]

took the truck to Auto zone to see what is that tester can tell me about how much AMP my starter draw or what not , The 1st test show the starter draw 620AMP the 2nd one show 592 AMp . According to the Guy that is so much AMP for a starter to draw , In his opinion he declare it bad .


What is the right drawing AMP for these starters .. Is that a valid test ?

 

[OLDBULL8]

That's about right, even as hi as 750 amps. He's thinking gassers, not a hi compression diesel.

That's why you have two batteries.