Rebuilt FI pump for early 91

[tkerrigan]

I sold my early 91, and it is occassionly, about once evey three weeks puking out huge clouds of white smoke for about 30 sec, then recovering and running normally. Any hints on what could cause this would be greatly appreciated.

If it turns out that we have to order a rebuilt pump, the truck has banks aftercooler, larger exhuast, and 14cm exhuast housing. Should we order the early pump (89-91. 5) or the later pump (91. 5 up).

The other question is who is a good vender, reasonable price and good quality?

Thanks in advance for any help.

 

[dpuckett]

For a direct bolt on fit, you'll have to get the 114 (89-91. 4)pump. I have been told have yet to verify on my own, that the 205 pump (92. 5-93) is the best of the VEs used on our trucks.



On to the cause of your smoke. The only thing I can think of in the pump that would cause that is the advance mechanism, but I'd think it'd be more consistent than every 3rd week. So that leads me to believe injectors or fuel supply system. Check your lift pump fuel pressure both before and after the filter, and check for any old, kinked or possibly collapsed hose. ALso check your return system. What about your tank and stuff back there? I'd think the fuel pump would be the last resort. Does the truck run alright otherwise? Is the smoke at idle or under load?



Daniel

 

[tkerrigan]

When I had the truck, it was my daily driver. It would only happen to me very occassionaly when I worked an 8 hour shift at work and only in the summer. My usual shift was 12 hours. It began when started, and went away after about 300 feet, once every couple of months or so. The guy I sold it to, only drives it on weekends, and it is happening more often, so it makes me thind that something is hanging up in the pump. I've tightened all the elect connections ie wax pellet heater and checked to make sure that it gets hot. The pump has over a hundred thousand miles, so I thought that it might make more sense to replace it rather than try to repair. Other than that problem, the truck pulls super hard, I have attended about three MMadness events pulling my travel trailer back and forth, and it never did it then.

 

[dpuckett]

I'd still check fuel supply lines and injectors first. Not to say it ISNT the pump, but other things that are cheaper and easier to remedy can cause similar symptoms.



DP

 

[Greenleaf]

Check the sensor that controls the wax motor (KSB system). The specs should be printed in the FSM along with a fuel injection pump manual or even the Cummins B operators manual. The system is explained in great detail, how to trouble shoot etc.