B7500 losing power

OLD GAR

Member

Equipment
MF210, FORD 8N, BIG TEX CH18,
Aug 3, 2015
69
5
8
ZWOLLE
My beat up B7500, along with hard starting has developed a reluctance to run over 1250 RPM. Push the throttle on up and it acts like it is flooding. Pours out black and white smoke I did research the B7500 thread but no joy there.
 

Bulldog

Well-known member

Equipment
M 9000 DTC, L 3000 DT
Mar 30, 2010
5,440
73
48
Rocky Face, Georgia
When was it serviced last, fuel filter, air filter, ect?

Does it have clean, fresh fuel?

Has it sat around with old fuel in it?
 

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
28,726
5,135
113
Sandpoint, ID
Along with the points that Bulldog brought up, try running it and when it starts to lose power remove the fuel cap and if it gains power it has a clogged vent.
 

lugbolt

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Equipment
ZG127S-54
Oct 15, 2015
4,843
1,598
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Mid, South, USA
Black and white smoke when the engine is loaded, or accelerated, is generally indicative of starvation for air.
 

OLD GAR

Member

Equipment
MF210, FORD 8N, BIG TEX CH18,
Aug 3, 2015
69
5
8
ZWOLLE
The air starvation might makes some sense. I've only done minimal service. I don't do dusty mowing or heavy digging or grading with the FEL. I do some toting back and forth, but no really hard usage. I usually put about 3 or 4 gallons of fuel a month so it isn't stale. I buy it at the local Chevron station in town. It really smokes if I put full throttle but won't do over 1400 revs. I also suspect some low compression for he just won't start without a loooonnnnnggg cranking time. I just give him a tiny breath of ether and he starts ok. This isn't just a new thing as I've had this clunker for about 4 but the refusal to develop reasonable revs is fairly recent. I live in west central Louisiana so the cold isn't a factor. I will save some other issues for another post.
 

OLD GAR

Member

Equipment
MF210, FORD 8N, BIG TEX CH18,
Aug 3, 2015
69
5
8
ZWOLLE
Thanks for the response! All of you were on the right track but what the "LUGBOLT" put me on to was the exact solution! I opened up the filter can and although it didn't look "too bad" I took it out cleaned out the canister and snapped it back in place without the filter. As soon as I started him up, two seconds of black smoke and smooth as silk, he just ran right up to 2500 revs! Thanks a lot fellows for getting me going again.
 

Bulldog

Well-known member

Equipment
M 9000 DTC, L 3000 DT
Mar 30, 2010
5,440
73
48
Rocky Face, Georgia
I opened up the filter can and although it didn't look "too bad" I took it out cleaned out the canister and snapped it back in place without the filter.
I wouldn't run it any without a filter. It would surprise you what just a short amount of run time it will take to trash your engine. We had a pissed off employee at the quarry ruin a 3408 Cat engine in less than one day running it without a filter. $150K lesson learned the hard way.
 

D2Cat

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L305DT, B7100HST, TG1860, TG1860D, L4240
Mar 27, 2014
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40 miles south of Kansas City
Yes, OldGar, you better listen to Bulldog. He has described a situation called "dusting an engine", you can/will ruin an engine in short order without an air filter.
 

alansz400

New member

Equipment
B7500. FEL, Piranha tooth bar, box scraper, post hole digger, 3 pt. bucket
Oct 26, 2013
265
0
0
Loudonville OHIO
I was surprised how much black dust came out of my air filter when I blew it out a few weeks ago. Seems like the exhaust coming out under the hood and the fan blowing it around and the air cleaner inlet being under the hood send the black soot right to the air cleaner.