Why won't it run ?

[sproutgrower]

Hello, I'm after alittle help. I have a 1972 (ish) M35A2, non-turbo. Just put in new Primary fuel filter, two shiney new batteries, and now she sharts like a dream, but if you let the revs drop below 1300rpm, she stalls !
I've bled off the 2nd & 3rd filter, and can see fuel going back down the injector return pipe, and as I say, starts every time...just won't run Any one have any ideas ? We want to go to the War & Peace show in 3 weeks...but at this rate may not make it

 

[gungearz]

Welcome to steel soldiers... I'd check the fuel injectors

 

[wsucougarx]

Hmm, could be the injector pump. Search for droop screw.

 

[WillWagner]

Did it run OK before you did the things you did?

 

[glcaines]

Ditto?

Also, have you changed the secondary filters?