Out of ideas trying to start a 98

Still trying to start 98 6.5 problem is I can pull glow plugs from heads and get a mist but when I try to start I get no smoke out the back end and it doesn’t even act like it wants to start also have all new Bosch plugs. The batteries are old 2014 but it still turns over, however when I check voltage I have 12.1, I took them to advance and and got 513 and 423 cca my question is is there a min voltage the pmd needs to spray fuel I think with cranking under load (with the plugs in) and heating glow plugs could it be pulling voltage down to much for the pmd

The motor needs to turn over fast, with old batteries it may not be spinning fast enough...

But shouldn’t I still get smoke out the back?

With the electronic pump there's no fuel until you break minimum RPM. It might be 200 RPM, but I'm not sure any more. What's the battery voltage(s) at cranking speed?

Bill D,
You indicated that there was no smoke from the back. Check your air intake and exhaust system, a small mouse nest can cause big problems.
Good luck
John

Try plugging in the block heater for a few hours before the next attempt to start it.

I believe min crank speed is 400rpm.

Big Green

I had a 94 that did that to me at that grocery store. Sounded like it was cranking fast enough but wouldn't hit minimum RPM to get the fuel solenoid to open. Have someone crank it while you have you hand on the solenoid and see if its clicking open. If it doesn't it time for batteries. Make sure the solenoid works first.

A 6.5 starts best when its whizzing over,. Slow rpm equals poor injector pressures,.pull couple of glows and manually verify they are working well