CAT 930G Troubles

[FFR1998]

Ahhh, where to start. Lets see. About 2 weeks ago the loader started giving us troubles starting in the morning and slowly losing power. Once we got it going it ran find through out the day. We found out the turbo went bad and replaced it, which gave us our power back. We also found a small hole in the gas tank, as well as one of the lines had a small hole. The line was replaced and the hole was fixed.

However the starting problem slowly got worse and worse. The loader would just die out, and still had trouble starting. Up to date, we have also changed out all the filters, replaced the VOP pump, the injectors, and the fuel lines thinking maybe they were clogged.

We have had two CAT mechanics out to our facility and they keep telling us something different. We have done everything they said and nothing is fixing it. They put the machine on there computer and it is saying there is nothing electrically wrong with it. It seems as though they are doing process of elimination and we just dont have the funds to play that game. We are definitely at a loss, and dont have any other ideas at this point.

As of today, once we finally got the CAT to start, it would run for 5 minutes and then just die out. This happened 3 times and now it won't start at all.

Any suggestions would be great! This is our only loader and we are unable to run our business without it.

 

[willie59]

Have you checked to make sure the fuel petcock coming out of tank is not clogged? Also, does the fuel system have any banjo fittings with screens in them?

 

[FFR1998]

We have checked the fuel petcock, and im not sure about the banjo fittings. I'd have to check with my yard supervisor in the morning. It seems that the fuel goes to the injectors for about 5 minutes (as long as it runs) and then just stops.

 

[willie59]

Well, I had to ask because we are not there working on the engine. You did mention that you replaced the injectors, the VOP pump (I assume that's the lift pump), and fuel lines. After doing all this, you should have a running engine. But you don't, so something has been missed, so just trying to cover everything. I don't know the engine in the machine, but some Cat engines use a screen in banjo fittings of the fuel line, some have a screen in the lift pump, other engines have no screens in the fuel line.

 

[FFR1998]

I am speaking to my yard supervisor right now aka, my fiance. He is on his way home and is going to get on here when he gets home. He can better talk about this mess as he has been working with the mechanic on it. Thanks so much for your help =) You have no idea how grateful I am we found this site!!!

 

[willie59]

I am speaking to my yard supervisor right now aka, my fiance. He is on his way home and is going to get on here when he gets home. He can better talk about this mess as he has been working with the mechanic on it. Thanks so much for your help =) You have no idea how grateful I am we found this site!!!

LoL...well, ya got guts jumping in and discussing this "mess" as you put it. I just hope someone here can help you out. I know nothing about this engine and I'm hoping the cavalry comes to the rescue here.

 

[FFR1998]

hahaha thanks! Im just a girl who has trash running through her blood lol. My father has been in the garbage business all his life and i'm the lucky daughter who inherited the gene lol.

 

[willie59]

Ahh...a trash bashin' machine! I've worked on a number of landfill machines. I would for sure drain and seriously check the fuel tank. Trash machines can get debris in places you wouldn't believe. I have worked on trash machines that have debris floating around in the tank that just hangs around until the machine is running, drawing fuel through the petcock. Then the piece of debris floats over to the petcock and clogs it up. Once the engine quits, the debris floats away.

 

[FFR1998]

hi, i'm Steve, the supervisor in charge. let me start by elaborating the details. we actually began having starting issues about 6 months ago. one of my men would start the loader in the mornings only by priming it first. we began noticing the problem getting drastically worse about 2 weeks ago. i was operating the loader the day it became a MAJOR issue. (this was NOT a good day as we also developed a steering issue the same day, but i'll get into that later) it began with a considerable loss of power, then it ran so sluggish that i had the throttle pinned to the floor while the engine only reached approximately 2000rpm's. the engine cut off immediately after that. the mechanic checked the obvious first.... fuel filters, fuel level, air filters, etc. we got it to fire back up with (don't kringe) a mist of starting fluid in the air filter housing of the intake. we also replaced the turbo figuring that was the problem cause we knew it was ready for a rebuild anyway. she ran fine after that and the power was a little better. we found a crack in one of the turbo hoses and replaced it. now we had all the power back. we also found a hole in the top of the fuel tank not knowing how it happened as the tank ismade of plastic. we patched it with epoxy, problem solved, but feared that grease and/or debris got in the tank so we replaced the fuel filters the next day. the next morning(and every day after that) the only way it would start was the same way(starting fluid). we've since stopped using starting fluid in exchange for a gasoline soaked rag held into the intake tube during crank. we've spoke with ringpower NUMEROUS times, purchased expensive parts, replaced what they've suggested to replace and we're still stuck with a broke-down loader. yesterday the loader died like it did the first day of our troubles. fed up with it, we insisted that a ringpower field service tech come out and troubleshoot it once and for all. he ended up doing everything our mechanic already tried, found nothing with an electronic diagnosis, and then suggested 2 more options. we AGAIN purchased and installed more parts today. after the installs we've had the loader start and die about 10 times through out the day. once we got it started it would run for no more than 10 minutes before it would die. each time it would bog down before cut off until the last few times when it would just die with no warning. now we can't even get the loader to start. one thing i forgot to mention was that every time during start-up in this past 2 week process, white smoke pours from the exhaust. but anyway, so we're at a loss. heres a list of repairs we've done so far:

- replace turbo and air to intake hose
- VOP switch (either provides or protects voltage to fuel system, so i've been told)
- replaced injectors
- replaced air filters
- replaced fuel filters
- replaced fuel lines from tank to primary filter and transfer pump
- replaced fuel transfer pump 6 months ago
- remove, clean and reinstall fuel lines and filter heads

we HAVE NOT checked the petcock or screens as you suggested, but that will be done first thing in the morning. any other suggestions or DEFINATE fixes will be greatly appreciated!!!!

if you'd like to hear about the steering issue, ask or i'll just start another thread on this issue. thanks in advance. ointhead :Banghead :bash :drinkup

 

[stock]

Well seeing as my alter ego has started I'll have a go.This is a problem that my nephew acquired on a 3640 JD symptoms are very similar to yours on the Cat engine so here goes,Open the injector return line and see if it makes a difference,on the JD it has a standyne pump and on the return line as it enters the pump housing there is a sneaky non return valve, installed in a pipe union.When we Isolated the issue to this union we removed it and looked through it loads of day light but no diesel return ,a glass ball is used with a spring and the spring had some crud build up on it and wouldn't open.
Washed it out with benzene , WD40 and air and away she went in a hack.

For one check the tank for a suction filter,and some times the lift pump may have internal filters fitted.Welcome too the both of you to the board and look forward to interacting with you and viewing pictures of your operation .

 

[bill onthehill]

I would be looking for debris in the tank or a loose line fitting letting it suck air in. Could some of the epoxy repair have broken off and gotten in the tank? The outlet from the tank may have a screen that is clogged. Have you tried a line from another temp fuel source to the lift pump? This will isolate the tank and lines as a source of problem.

 

[FFR1998]

Morning guys! I showed all this to our mechanic and he has tried all of the above. Any other suggestions at all? :Banghead

 

[Steve Frazier]

Have you tried running the machine with the fuel cap removed? I haven't seen that mentioned yet. I don't know the machine or how the fuel tank is vented, but it seems you've tried everything else. It does seem like it stalls pretty quick for it to be a vent problem but stranger things have happened.

 

[FFR1998]

I'm not sure. Apparently after I left the yard yesterday, there was a water line that cracked. The mechanic is replacing that now. It's just one thing after the other. I know the water line doesnt have to do with the loader quitting because this has been happening before yesterday. I will definitely ask him though, when he comes back into the office. As I said, we will try anything at this point!

 

[FFR1998]

Have you tried running the machine with the fuel cap removed? I haven't seen that mentioned yet. I don't know the machine or how the fuel tank is vented, but it seems you've tried everything else. It does seem like it stalls pretty quick for it to be a vent problem but stranger things have happened.

OK! We took the fuel cap off like you suggested and so far the loader has been working for about a half hour with no problems! So why would this happen and what can we do to fix it? :beatsme

 

[FFR1998]

:cussing:idontgetit Ok update, She's been running for a little over an hour and she just died!

 

[Cat is ALL]

Fuel pump I would say. We've had multiple times that our 938G has had this exact problem and its the same thing everytime. It is not the whole fuel pump, but I will get details for you tonight. It is like you said, you are driving it and it's fine then out of no where it just starts to die no matter where the pedal is. If you use the primer while its running can you get it to limp some more?

 

[Partsdude]

Based on the earlier posts my WAG is the faulty fuel cap combined with something in the tank is the culprit.

Do you have a parts book for this unit? Look to see if there is an access port on the tank to see if you can open her up and have a look / cleaning.

If not, try running the machine with an alternate fuel source and see if that works.

 

[FFR1998]

Fuel pump I would say. We've had multiple times that our 938G has had this exact problem and its the same thing everytime. It is not the whole fuel pump, but I will get details for you tonight. It is like you said, you are driving it and it's fine then out of no where it just starts to die no matter where the pedal is. If you use the primer while its running can you get it to limp some more?

More details asap would be great! At this point the boss is so frustrated he is about to shut the entire company down because we cant find the problem and have any more funds to keep playing process of elimination. At this point we cant even get it started again to even try what you last said. The only way of starting it is to soak a rag in diesel.

 

[FFR1998]

Based on the earlier posts my WAG is the faulty fuel cap combined with something in the tank is the culprit.

Do you have a parts book for this unit? Look to see if there is an access port on the tank to see if you can open her up and have a look / cleaning.

If not, try running the machine with an alternate fuel source and see if that works.

We did have a parts book for it but in all this mess the mechanic took it this morning to go speak to cat who is not being very helpful at all, which causes more frustration. So I am unable to see if there is an access port. What would be an alternate fuel source that we would be able to use?