2001 VP 5.7 GSI PEFS no start

[Lubak572]

Trying to get my new motors to fire. Upgraded my 2 5.7 GSI's to brand new GM Marine 6.2 long blocks. I used the original intakes (cleaned up) and put new starters, plugs, cap, rotors, wires, water pumps, exhaust (hardin marine seaward series), rebuilt TBI, sent injectors to witchhunter performance for R&R,new batteries, battery charger, and sent ecm out to MEFI Bob for remapping with the larger 6.2's, Motors cranks no start, on both motors no codes thrown on my laptop running diacom software. Had several motor head buddies look at it-can't figure out. Just saw while cranking port motor engine speed while cranking only got as high as 146 rpm. Heard have to get to 300 rpm to fire. Help??? Trying to get these to intial fire to set base timing.

 

[alldodge]

Yes need at least 300 rpm

Are the injectors firing?

 

[Lubak572]

Yes need at least 300 rpm

Are the injectors firing?

Yes I believe, but don't appear to be spraying enough fuel, I believe it is an ignition issue. I used original dizzy looked good. What would cause slow crank? Sounds fine turing over just doesn't get past 150 rpm. The 6.2 rotating assembly wouldn't slow the starter down vs, a 5.7 -would it?

 

[alldodge]

Weak starter, battery cables, not enough battery
Tach may not be accurate

 

[Lubak572]

NEW VOLVO PENTA 4.3L 5.0 5.7 350 MARINE STARTER 1998-UP 3860566 3860566 3885317, cables looked good-were cleaned up, and 890CCA

Duracell AGM Deep Cycle Marine and RV Battery, Group Size 34M (brand new 2 of them-read 13.5 on rhinda) even had them switched in both for emergency starting. I used the engine speed of the rhinda plugged directly in real time. I saw it go up to 146 RPM while cranking. It was varying so I assume it was accurate-sounded normal to me cranking-didn't appear/sound slow just was watching digital engine speed data on laptop-never hit 300. I believe it has to fire plugs. Correct?​

 

[alldodge]

That is plenty of battery.
What kind of starters, PMGR or other?

 

[Lubak572]

Pmgr

 

[kenny nunez]

I bet that the crankshaft is rotating at the required speed but the signal is coming from camshaft speed since the rpm readout is low.
Are the signal pick ups in the same place as the original engine?
Of course this is just a guess.
Maybe someone can post a wiring diagram of your model.

 

[Lubak572]

I bet that the crankshaft is rotating at the required speed but the signal is coming from camshaft speed since the rpm readout is low.
Are the signal pick ups in the same place as the original engine?
Of course this is just a guess.
Maybe someone can post a wiring diagram of your model.

Yes all original sensors , motor is a TBI no sensor on crank or cam. No dtc or faults on either motor.

 

[alldodge]

PMGR are permanent magnet type starters. They are smaller but put out more torque

 

[Lubak572]

PMGR are permanent magnet type starters. They are smaller but put out more torque

Yeah I assume those are all good. What a PITA trying to get these motors fired.

 

[alldodge]

Hit it with a very small amount of starting fluid

 

[Lubak572]

Hit it with a very small amount of starting fluid

Ok I will try later, unfortunately it is raining right now, and boat is outside on trailer in my driveway. Man I need to buy/ build a big pole barn... Thanks

 

[kenny nunez]

When you turn the key on, without turning to the start position, does the fuel pumps prime for the 2-3 seconds?

 

[Lubak572]

UPDATE:
Ended up being BOTH fuel pumps were bad. Motors are running now.