B7100 running on 2 cylinders

FerndaleWAB7100

New member

Equipment
B7100
Aug 16, 2012
5
0
0
Ferndale, WA
I ran my early 80s B7100 3 cylinder diesel out of fuel last week. I loosened the fuel lines where they go into the injectors and cranked the engine over until diesel pumped out. I was able to start the engine but it is running rough and only seems to be running on two cylinders. With the engine running I re cracked the fuel lines and noticed poor engine idle with the first two cylinders (cylinder closest to battery and center cylinder). When cracking the fuel line going to the cylinder closest to the radiator there was no noticeable engine idle change. Fuel does stream out. I pulled the injector out and tore it apart and cleaned it up. Reinstalled but that didn't fix the problem. Any suggestions? Thank You, John
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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Sandpoint, ID
Either take it in (and I would take all of them) and have them tested before you do any more, if they test good then the problem should be in the injection pump, it could have sucked something in and clogged up those works.
 

MagKarl

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L245DT
Aug 2, 2010
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Olympia, WA
Have you tried cranking with the suspect injector hanging by the line if that's possible? Wondering if it is actually spraying or not.
 

FerndaleWAB7100

New member

Equipment
B7100
Aug 16, 2012
5
0
0
Ferndale, WA
I have not tried hanging it from the fuel line and turning it over. I'll give that a try. I know I'm getting fuel to the top of it just not through.
 

coachgeo

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L225 w/woods Few Mowers & Back Blade, D722 in Motorcycle (Triumph Tiger), LMTV
Nov 16, 2012
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48
Southern OH
I have not tried hanging it from the fuel line and turning it over. I'll give that a try. I know I'm getting fuel to the top of it just not through.
MAKE SURE YOUR NO WHERE NEAR THAT INJECTOR !!!!!!!!

Injectors blow POWERFUL enough to deeply pierce the skin and cause sever deep poisoning. Proceed with this test if you dare with EXTREME CAUTION. Reminder a stream of fuel may ricochet toward you as well.
 

Apogee

Member

Equipment
B6100, B7100, B8200, B9200, G4200, L175, L35
Jan 22, 2012
518
0
16
Tacoma, WA
You likely have air in the injection pump. Bleed the system all the way through starting from the fuel filter and you will likely solve the problem.

The injection pump is actually made up of 3 little pumps inside the housing. Either one was damaged when it ran out of fuel or there is an airlock in the one for the dead cylinder.

I recommend starting from the fuel filter just so you're 100% sure there are no air bubbles trapped any place else in the system and work all the way through to the other end.

Please keep us posted on what you find.

Good luck,

Steve
 
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