Engine Stalling Low Revs

[JC]

Hi. Have a Bertam 31 with Cummins 250's 6bta's. My port engines has been reacting strangely. Has the following symptoms....

When starting cold the engine will fire right up.... after engines get up to crusing temp and after a while of use if I come back down to idle RPM's and go from forward to reverse the engine will stall. When I try to start the engine again it will take 4-5 seconds and have to advance the throttle to get ti going again. Seems the problem is at low RPM;s the engine is either not getting enough fuel or a voltage problem maybee with the injection pump shutdown selenoid?? Only happens once the engine is hot.

I already had trouble with the shutdown selenoid not getting voltage once so I am assuming there might be too much resistance in the cable and maybee when the engine compartment gets hot there is a voltage drop in the cable?? I am not too inclined to think this is it as I would think this would affect high RPM's also.


Maybe transmission related??
Faulty Injector??

Well I better shut up and let the knowledgable help me. This is a pain when trying to back down on a hot marlin!!!

Thanks,

JC

[Kevin]

JC,
I have no knowledge of subject matter but remember seeing similar problem as your last week. Here is the thread.

http://bertram31.com/newbb/viewtopic.php?t=1669

It is located just a little way down the main page also

[In Memory of Vicroy]

JC - sounds to me like probable fuel restriction and/or air in the fuel system or maybe a weak fuel lift pump. I'd also check the oil level in your gear. You can hot wire the fuel solenoid direct from the battery to check on wire harness issues.

UV

[In Memory Walter K]

How low is your idle when hot? If you control your pull back to no less than 700 rpms and then shift to reverse, does this happen? Walter

[JC]

Thanks for your answers. I went thru the posts and this is definetly a good starting point. So my logic tells me

1) I should first try to hot wire the shutdown selenid and give this a try to see if it is an electrical issue. Would this be the only electrical issue to be concerned with??

2) In case 1 doesnt work try changing the lift pump

3) In case previous dont work recheck and tighten all fuel conetions.

4) Check injectors??

My Idle RPMs are somewhere around 700-800 I believe. Yes I believe this is happening above 700.

Thanks!!!!

JC

[In Memory of Vicroy]

JC - yes, the fuel solenoid is the only electrical issue. OddS of it being an injector issue are low.

Your logic is good.

UV

[capy]

I had a leaky fuel pickup line in my oil slinging dump truck motors that behaved exactly the same way.

Changed the line and it fixed it going on 5 years now.

[Brewster Minton]

Air in the fuel system maybe but you need Bruce