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CAT 420D Won't Start

CATinLiberia

Active Member
Joined
Aug 14, 2012
Messages
26
Location
Liberia, West Africa
Occupation
Missionary and Community Development
I have a CAT 420D (PIN # CAT0420DAFDP26886) that won't start. Here's a little history and a description of what I've tried...

My backhoe was shipped from the states to Liberia, West Africa about six years ago. The first few years, it was used lightly in a small mining operation, but sat most of the time. From 2012-2013, I used it in an equipment rental company and ran 10-20 hours a week for about 10 months. I never had a problem with the engine starting. No engine problems at all. The only issue I had was engine run-on when I turned off the key. Because the fuel quality is poor in Liberia I changed the fuel filter about every 80-100 hours and cleaned the fuel tank every 300-400 hours.

I parked the machine 24 months ago with a little over 2,000 hours on it. At the time, it was running and working perfectly. I live in Monrovia near the coast, so the machine has been subjected to some salt air and has sat out in the elements since arriving in Liberia (Monrovia receives about 17 ft. of rain during the six-month rainy season). The exhaust pipe has been covered nearly the entire time. This machine sat for 12 months back in 2010, but didn't have any problem starting back then.

I used the starter from this backhoe on one that I was selling, so I just installed a new aftermarket starter (not from CAT). I also installed a new 105 amp Bosch maintenance-free battery, a new key switch and a new direction control switch (both from CAT)... I stole a lot of parts to sell my other machine. :)

When I first tried to start it, the engine seemed to crank slow and would not fire. No smoke was visible from the exhaust pipe. I checked all the battery connections and discovered that the ground on the frame was very hot. After cleaning the ground, it cranked a little better, but would not fire (the engine turns OK a couple revolutions, then slows way down. I bled the fuel system and also verified fuel was coming from the injectors. Even though I never needed to heat the glow plugs due to the tropical climate, I checked them (they were wet with fuel). I cranked the engine with the glow plugs out and everything looked and sounded as expected (I don't have access to a compression tester). It appears the glow plug switch doesn't work, but I was able to use a jumper wire to heat the glow plugs. Still nothing fire, but I did get a little white smoke.

Out of desperation, I held a gasoline-soaked rag over the intake. A little white smoke, but still no fire. This is when I began to get really worried. I've also connected jumper cables from my diesel pickup to see if the engine would crank better, but it didn't help.

Diesels are not my specialty and the local mechanics have limited training and experience on these engines, so I am hesitant to open the engine. I don't have access to replacement parts here, so everything has to be shipped or carried on someone's luggage.

I'm really at a loss on what to try next. Maybe swap the starter to see if I can get it to crank faster? What else should I check? Any thoughts? Ideas? Advice?
 

Deon

Senior Member
Joined
Jul 25, 2010
Messages
768
Location
Nova Scotia, Canada
CATinLiberia,
Have another look at your battery. You should have about 1000 CCA (cold cranking amps) not 105 amps.
But the jumper cables should have helped if connections and wires are all good. If it cranks too slow, it will not start even if everything else is perfect. I would say you have wrong battery, bad wires or connection or defective starter.
 

hookedondiesel

Senior Member
Joined
Jan 24, 2013
Messages
503
Location
Sault Ste Marie Ont. Case 1835C
I agree, concentrate on getting her to turn "faster" re-check all your battery connections,
going to ground and even the starter, salt may have weakened the contact points with corrosion. If you see white smoke, then it sounds like it wants too start, she needs to turn a little faster, i would say.
 

Cmark

Senior Member
Joined
Jan 2, 2009
Messages
3,176
Location
Australia
Ok. Here's what I think are the pertinent facts;

Parked outside for two years equals corrosion.

New starter motor and battery pretty much eliminates these two items as a problem. (Although admittedly not guaranteed)

Hot cables suggests plenty of amps so battery voltage doesn't appear to be a problem.

Engine turns a couple of times and then slows down.......!

My best guess is that the hydraulics are bogging the engine down. What we call a parasitic load. After a couple of years outside, the hydraulic controls may have started to seize up and someone might have been playing with them and left one stuck on. I would suggest you check that all the hydraulic controls are in their neutral position.
 

CATinLiberia

Active Member
Joined
Aug 14, 2012
Messages
26
Location
Liberia, West Africa
Occupation
Missionary and Community Development
CATinLiberia,
Have another look at your battery. You should have about 1000 CCA (cold cranking amps) not 105 amps.
But the jumper cables should have helped if connections and wires are all good. If it cranks too slow, it will not start even if everything else is perfect. I would say you have wrong battery, bad wires or connection or defective starter.

Hey Deon, thanks for the feedback!

Regarding the battery, they commonly refer to the Ah, not CCA, as we do in the states. I checked my battery's specs on the Bosch website and found that my 105 Ah has 570 CCA's. Definately undersize if the target is 1,000 CCA's! I used this size in the past, but admit that it always seemed to drag some (though it always started). So, I went back to my parts store and dropped some serious coin on a 210 Ah battery with 1,300 CCA's.

Upon installation, it cranked much better, but still didn't start. As before, I had a little white smoke come from the exhaust. I also checked the connections and didn't get burned. :eek: I can say with confidence that the crank speed is not the problem.

Any other thoughts?
 

CATinLiberia

Active Member
Joined
Aug 14, 2012
Messages
26
Location
Liberia, West Africa
Occupation
Missionary and Community Development
Ok. Here's what I think are the pertinent facts;

Parked outside for two years equals corrosion.

New starter motor and battery pretty much eliminates these two items as a problem. (Although admittedly not guaranteed)

Hot cables suggests plenty of amps so battery voltage doesn't appear to be a problem.

Engine turns a couple of times and then slows down.......!

My best guess is that the hydraulics are bogging the engine down. What we call a parasitic load. After a couple of years outside, the hydraulic controls may have started to seize up and someone might have been playing with them and left one stuck on. I would suggest you check that all the hydraulic controls are in their neutral position.

Cmark- Good thoughts on the possibility of a parasitic load. Our old compound is currently used as an orphanage, so I have no doubt some young "yellow machine operators" have moved the hydraulic controls. :D I will check that out and make sure all controls are in neutral positions. Regardless, it is now cranking fast enough that the engine should fire.

Any other thoughts?
 

Delmer

Senior Member
Joined
Jan 3, 2013
Messages
8,865
Location
WI
You said you didn't have any white smoke at first, but later did. And you bled the fuel system, what did this bleeding involve? The last step in bleeding is to crack (1/2 turn loose) the injection line at the fuel injector, and crank until you don't get any bubbles. Give it several minutes between cranking attempts, keep a charger on it etc.
 

CATinLiberia

Active Member
Joined
Aug 14, 2012
Messages
26
Location
Liberia, West Africa
Occupation
Missionary and Community Development
You said you didn't have any white smoke at first, but later did. And you bled the fuel system, what did this bleeding involve? The last step in bleeding is to crack (1/2 turn loose) the injection line at the fuel injector, and crank until you don't get any bubbles. Give it several minutes between cranking attempts, keep a charger on it etc.

Delmer- Thanks for the feedback. To bleed the system, I only cracked the lines loose at the injector inlets and cranked to verify fuel and pressure in the line. I didn't crank it too much... just wanted to see fuel squirt a few times and then pulled the glow plugs to verify fuel in the cylinder. This worked last time, but the backhoe didn't set as long.

Sounds like I just skipped to the last set, assuming that fuel pressure at the injector inlet would indicate the system is mostly bled. Can you share all the steps to make sure I adequately bleed the system?

Thanks!
 

Delmer

Senior Member
Joined
Jan 3, 2013
Messages
8,865
Location
WI
I don't know that pump so I can't say the proper procedure. You should be fine by now, this has cranked a couple of minutes by now right? I WOULD repeat the cracking the line and crank until you see no bubbles. One line at a time is the way I've always done it, but can't remember if there is a reason for that or not? One is usually sufficient and then tighten it up when it fires, but you probably want to do each in turn.
 
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