Model 784 Diesel engine surging and then crank but NO start

My trusty (up to this point) 784 diesel started engine RPM surging just as I was finishing snow plowing so I brought it into the garage. Later on I tried starting it and it wouldn't fire once. Am hoping someone who has had this issue and familiar with this model (Jmb2 or others) can tell me what the causal factor(s) may be and how I might go about fixing it. ALL advice appreciated as I am NOT a diesel mechanic, just an old farm boy who wants to have a reliable vehicle for plowing this winter.

Hi John,I am assuming lots of fuel in the tank then I suspect a fuel flow problem to the injection pump as this will cause the
RPM surging.
Probable causes:
1) Junk in bottom of fuel tank blocking the tank outlet - test with clean bucket, loosen fuel tank filler cap, remove fuel line
at the input of the first fuel filter and let it drain into the bucket. Fuel should run out at the full of the pipe. If not
quick fix is to use an air gun to blow back into the fuel tank, permanent fix is draining fuel tank and removing outlet shutoff
valve and cleaning.
2) Clogged fuel filters.
3) Some models have a braided fuel line that goes across the front engine from fuel filter to the injection pump and sometimes
the material collapses inside the braid blocking fuel flow.

If you have an air gun, you can try pressuring the fuel tank a little and then try starting it.

Good luck
JimB

What Jimb said fuel then filters then flow if they are the glass bowls do they leak. If spin on are you loosening the bleeders on the filter house they look like a hex bolt with a screw slot in them. I suspect plugged or frozen fuel. See if it is gelled. If so thaw and ad your choice of snake oil.

Thanks for your input JimB2 & Caterpillar guy. I always like to see follow up from those asking for help and getting it. I know when good folks like yourselves provide help, you do it as you like to share your knowledge and (perhaps) experience having faced a similar issue. Thanks and follow-up words, however, are in my opinion always good policy.

I had plenty of fuel in the tank but did dis-connect the feed line to the fuel filters and noted good flow . Flow was good also out of the spin on filters. In spite of this, I pressurized the fuel line back to the tank a couple of times - it really didn't seem to help the already good flow. I checked over the braided/metal delivery line running from the filter outlet to the pump inlet and that seemed good. Was hoping I would NOT have to change this as it didn't look like fun.

After the fuel line blow back to tank, I tried starting again - after a somewhat long crank it did fire right up; go figure. Maybe there was a temporary fuel flow interruption or some issue with summer blend diesel (now has "snake oil" in addition to winter blend diesel). I took it for a workout and there were NO issues as previously experienced.

I appreciate your quick and beneficial input and just wanted to let you know "the rest of the story" and to thank you both. javascript:emoticon('')

Glad you got the issue fixed. I was going to reply on the gelled fuel but got beat to it.

I run Diesel Kleen summer and winter in my tractors. Summer I run the normal and winter the anti-gel formula. Have also used Howes from time to time.

Always had good luck doing this. Hope this helps.