engine thinks about starting, but not quite.

Engine troubles? Try here.
Post Reply
yaknowthatguy
United States of America
Posts: 69
Joined: Wed May 20, 2009 5:48 pm
Location: Greeley, CO
Contact:

engine thinks about starting, but not quite.

Post by yaknowthatguy » Sat Jun 20, 2020 2:09 pm

hello all. working on resurrecting my 712 and running into some trouble.

Truck wants to start but won't quite get there. I can turn on power at the main, turn the ignition, and get power to dash and lights no problem. I press the starter button and the starter will engage, and the engine tries to start, but won't quite get there - it'll turn as long as the starter is turning, but once the starter button is released the engine slows turning and stops. I haven't found any loose electrical connections.

Fuel delivery is 4.5-5 psi. Batteries are full capacity. Carbs seem to have appropriate volume of fuel. Truck is garaged, fuel is clean with stabilizer. Fuel filter is not clogged.

Any ideas or suggestions would be greatly appreciated. Thank you!
712 amb. under construction.

User avatar
rmel
United States of America
Posts: 1154
Joined: Sun Sep 25, 2011 12:19 pm
Location: Woodside, CA
Contact:

Re: engine thinks about starting, but not quite.

Post by rmel » Sat Jun 20, 2020 3:35 pm

When you say "it'll turn as long as the starter is turning"
do you mean there is some ignition but insufficient to run on it's own?

Might want to check the condition of the points and condenser and
check to see if the distributor got rotated -- not likely. But if your
getting some ignition but not sustained could be a spark delivery
problem.

If your not getting any ignition, add to the above carb solenoids.
Puller: 71' 710K 2.7L EFI aka Mozo
Follower: Sankey MK 3, 3/4 Tonne
Rescue Pinz: 73' 712M

Driver: Ron // KO0Q

yaknowthatguy
United States of America
Posts: 69
Joined: Wed May 20, 2009 5:48 pm
Location: Greeley, CO
Contact:

Re: engine thinks about starting, but not quite.

Post by yaknowthatguy » Sun Jun 21, 2020 2:19 am

yeah, that's a good way to put it - seems like insufficient spark. You can hear it try to catch, but it won't quite do it. The truck had Pertronix install a while back, and has been driven with it, so my suspicion for distributor issue is low - but the fuel cutoff solenoids sound possible, and we'll be back under the doghouse tomorrow. Thanks for the guidance!
712 amb. under construction.

User avatar
4x4Pinz
United States of America
Posts: 1013
Joined: Sat Oct 24, 2009 6:17 pm
Location: arizona

Re: engine thinks about starting, but not quite.

Post by 4x4Pinz » Sun Jun 21, 2020 8:33 am

Check your breakers. If the one for the solenoids is tripped it will cause those issues. Also the rotor or internal of distributor cap can get corrosion and cause issues. Just because it has petronix or was running does not mean build up on the inside of the cap won't develop I

Post Reply