Starter motor engages fine, but turns the engine over very slowly. Like it is laboring. Batteries are about 6 years old, voltage and specific gravity said they were so so, so I replaced them. All battery connections clean and secure. Voltage when engine is running is 14.5 or so. I have not checked alternator current output, but voltage is fine. Still starts very slowly. I have put at least 3 starters into the truck in 100k km. First one I figure was the contacts as it was a click click start situation. Will tired starter contacts give a slow engine start? It seems like I need to go under again and swap out another starter. Any suggestions?
Thanks
Alan

 

Starter contacts either work or don't. I replaced my contacts and no problems since. My guess would be batteries. I was experiencing similar issues with slow starting -- just put in 2 new Interstates and she fires right up. Only got 4.5 years out of the last set. 6 years is darn good!

 

In my experience, the only way to really test batteries is out of truck with a load tester. Also I learned a lesson about cleaning battery terminals and connectors this spring. I have cleaned a lot of battery terminals over the years with a good brand of manual cleaner. After a bunch of old codgers scolded me enough times this spring I added a paste of baking soda and distilled water to my battery post cleaning regimen. WOW - I will never go back to just the wire brush. 4 months later, those contacts are still amazingly clean. The neutralizing action of the baking soda is amazing and has longer lasting effects than I ever expected. Between REALLY heavy draw starter motors and the draw of our toasters (combustion preheaters) we need an awful lot out of our batteries to get these things started. Before you replace your batts, give them every helping hand you can.

 

I have replaced the batteries, and no appreciable improvement in starting. Looks like I will be trying a new starter. Do you guys recommend a brand for the replacement starter. I seem to be getting less than stellar life out of my last supplier. I will dig up the receipt and hopefully it is still on warranty.
Alan

 

Foster truck sell OEMs........ Not cheap, but will be the next one I buy.

I have run the NAPA brand new units, so so success, 1 died within the month, the second has been on there for 2 years now.

 

Have you ever done a voltage drop test on the cables? It could be a bad cable.

Rick

 

I too would definitely stay away from the remans and jobber starters, and make a fresh start with a new OEM unit.

 

go with an oem and after years of service drop in new contacts then run it for a few more years.I have not had good luck with after market starters they go bad way to fast.

 

Did a voltage drop on starter positive cable this morning, 0.2v. Starter is less than 1 year old and still on warranty. Re and re starter and ta dah, truck starts like it should. At least I am getting good at putting starters in and out. At least 3 starters plus twice more for crankshaft position sensor.
Alan

 

I would do a voltage drop test between the engine and negative terminal of the battery just for good measure. Was that test on the positive cable just sitting or during cranking? .2 volt under load is fine but if it is no load then you need to recheck it under load. That would be a fairly large voltage drop for a cable that large at no load.

Rick

 

The positive voltage drop test was under cranking load. I didn't do a negative voltage drop at the starter, only checking drop between battery post and cable clamp. I feel pretty good though as the new starter spins her up smartly. As always, I thank all on the forums here for all the help that is available. Sure has helped me out over the years.
Thanks.
Alan