How to troubleshoot/fix starter 8.0 V10

[Viper_cobra]

Hi. New to this forum. Started an alternator thread and got super support, thank you so much!
I therefore would like to see if anyone can help me with an issue that came today.
So, I build an AC-Cobra replica and use the Ram 8.0 magnum V10 from -96 (I think).
To get it running I have connected a Maxxecu ECU. Have started the engine a few times but haven’t managed to get it run alright. This week I have worked intense with getting it run properly. After hour of just running on crank without injectors activated to get the proper synchronization It suddenly seems to run slow on crank (less than 100rpm) and my ECU therefore looses track of the crankshaft trigger sensor.
Possible causes:
- None/little oil from oil pump causes cam or crank to getting damaged/stuck and therefore the cranking runs heavy. Unlikely(?)
If this is the case. How to check. What would first break?

OR

- Starter is worn, 25 years old and now has run for one hour the past week. Likely (?)
if it’s the starter. What causes could it be and how to check them...? So far I have checked:
- Cables. Looks ok but will make an adjustment tomorrow
- Brushes. Took the starter apart and brushes looks worn but ok
- Rotor. looks worn

am I Missing something. Is there anything else to look for. I ran the starter outside the car and it seemed to work ok. But it was making noises a little bit. Could it be that the rotor is worn and once the starter gets load, it looses rpm/torque...?

anyone who has any ideas

 

[Viper_cobra]

Have serviced the starter now and it runs better but since I run an aftermarket ecu the trigger synchronization is not as optimal as the stock ECU. I would therefor like to get more boost when cranking. If I’m correct the stock starter for V10 -96 is 1,4 kW. Anyone who can tell if there is a bigger one that fits..? I’ve seen that the Cummins diesel uses a 2,5kW. Would be great if I could marry the two of them
Together...
Anyone who has tried?

 

[Viper_cobra]

One
Additional question, If anyone can tell.
what is the crank rpm on the V10. My guess is that I am
Below 100rpm now.

 

[Treburkulosis]

I would try and source a mini starter. Not sure if the Viper has the same starter. I could ask my buddy. He has a 97 GTS. I know when I was building SBF motors I always ran a stock mini starter. They never failed to start.

 

[Viper_cobra]

Good idea treburkulosis! Feel free to check with your buddy.
I have a SRT starter motor from an -07. Tried to marry the two of them but they look quite different. (However, the flywheel and the small cogwheel in the ram starter motor are taken from the SRT viper since the ram had auto tranny and the viper/cobra has the manual.

 

[Viper_cobra]

Problem solved. As mentioned, the starter got better after some TLC. However it didn’t turn good enough. Hooked up an extra +cable and ground. After that it fired right up. I guess that the main circuit switch which kill the + supply from the battery isn’t strong enough and I loose a lot of current through that one.