New 988H Its here!

[NL1CAT]

You're new here, but if you back and read the horror stories they had to tell about the L350, you'd probably agree that yeah, they can say the Cat is better.

Hey Alco,
He was talking about the operating side of it
The 330 series weren't the best machines but the 350 is allot better , shame that coalburner had a 350 moth.
Volvo's are very good loaders and very popular over here.
Strong , silent , good to operate .. 220's are beasts.

 

[Magnum]

Exactly, there is no question about that Volvo failed to deliver a reliable machine and perhaps there are more quality issues on the L350 compared to the 988. My experience is that Cat has got some quality problems with their machines as well. So I just want to hear the operators side of it.

 

[alco]

My point is, they never really got to operate it, it was always down. I see it like this, a machine that won't stay running is a pain to operate, so I stand by me earlier post.

 

[John C.]

As I recall they had several engine failures a couple of axle failures and lots of problems with the electronics.

Quite possibly there is better service or different expectations in Europe than in the States but from what I read of the problems the coal man had with his Volvo, it appeared to have many design problems and real poor follow up from the dealer and manufacturer. Could this be a machine built in the States as compared to a European built machine? I don't know.

After reading all that many would definitely shy away from the Volvo brand.

Thanks for the opinions from the continent.

 

[NL1CAT]

As I recall they had several engine failures a couple of axle failures and lots of problems with the electronics.

Quite possibly there is better service or different expectations in Europe than in the States but from what I read of the problems the coal man had with his Volvo, it appeared to have many design problems and real poor follow up from the dealer and manufacturer. Could this be a machine built in the States as compared to a European built machine? I don't know.

After reading all that many would definitely shy away from the Volvo brand.

Thanks for the opinions from the continent.

I don't know about the service cause I haven't been in the states but we dislike as much a machine that's in the workshop all the time.
The design of the 330 came from the vme (Volvo Michigan Euclid) era so it wasn't really a Volvo from the ground up I guess.

Lot's of Cat's are build in Europe .. Liebherr is from Europe and so is O&K , Demag to name a few.

It's a shame to stay away from Volvo.
Ok the 330 and 350 maybe after reading coalburners story but
The smaller loaders (from 220 and down) are good machines.

My point is, they never really got to operate it, it was always down. I see it like this, a machine that won't stay running is a pain to operate, so I stand by me earlier post.

That I agree on.

 

[r00t]

Volvo 350F is a new-developed machine of Volvo from scratch, and is not based on the old 330th

I think he got a bad machine, simply, and Volvo should have replaced it, and borne the full cost. There are lots of 350F's going around the clock without problems, some have some issues, but that's for the dealer and Volvo CE to solve. It's like with all other brands.

I think you have a problem with the Volvo dealer's service and attitude, just as we have problems with the CAT dealer here. Good equipment, bad organization abroad.

... and all make lemons sometimes.


I want to run Caterpillar equipment, but it's not really and option over here if you havent got your own workshop crew, and huuuge company wich the dealer listens to when it comes to guarantee and things like that.

I feel sorry for Coalburner, and ashamed to Volvo and the dealer did not solve his problem and compensate him. They should have put another machine there that showed how good they actually are. And figured out what went wrong in the production.

 

[kshansen]

I'm new to this site but have been working on loaders since the early 1970's. The old 87A 988 Cats!
In our company we have a few 988H's at various quarries in NY state. We have been having a problem with ours and I have been told at least two others of the same vintage have the same "problem". Just wonder if anyone else has seen this. The one at my location is S/N BXY00384.

What ours is doing is this: After dumping bucket into haul truck and letting bucket return to level then if operator rolls bucket down to try to dig under ledge on quarry floor. When bucket is then lowered to ground it will not hold position but rolls back to level. However if bucket is lowered to ground in a level position and then the operator moves the bucket level forward it will easily pick the front of the machine. While I was laid off this winter they brought an outside contractor in who used to work for the local dealer and had worked on this machine while still at the dealer. I'm told he did the calibration on the control valve and checked pilot pressures and found nothing out of line. It was then decided that problem was in tilt cylinder. I had more or less ruled that out from the little I had played with it but he removed cylinder and took it to his shop to repair it. Well as it turned out there was nothing wrong inside. Right now the machine is back together with the problem still there.

For got to mention this loader does NOT have ride control, besides I would not expect that to have an effect as I believe that only functions on the lift circuit and our problem is as far as I know only on the tilt circuit.

 

[kshansen]

Just thought of an unrelated problem we had that had us pulling our hair out for a few months. The monitor system was at random times telling us our trans filter was plugged. I could write a book on the things I did to try to cure this but to make a long story shorter the actual problem was a temperature sensor on the top of the range transmission had a defect that somehow was activating the plugged filter warning alarm. Maybe five minutes to screw in new sensor and problem is gone. If anyone needs part number of this sensor and exact location let me know. Or if you want the whole gory details of what was done before finding it let me know.

 

[JDOFMEMI]

Your tilt problem sounds to me like it is in the valve. From the symptoms, it is letting oil out of the head end to let the bucket curl down by gravity, but somehow letting air in the lower end of the cylinder instead of oil. When you put it down, the air compresses, and the bucket curls back up to where it was.

When you do the same operation on the ground, you have to force the bucket down, so it does so under pressure, and therefore stays since it is full of oil instead of air.

So, if I am right, the question is, Where is the air getting in at???

 

[Nige]

Just thought of an unrelated problem we had that had us pulling our hair out for a few months. The monitor system was at random times telling us our trans filter was plugged. I could write a book on the things I did to try to cure this but to make a long story shorter the actual problem was a temperature sensor on the top of the range transmission had a defect that somehow was activating the plugged filter warning alarm. Maybe five minutes to screw in new sensor and problem is gone. If anyone needs part number of this sensor and exact location let me know. Or if you want the whole gory details of what was done before finding it let me know.

Plugged filter alarms are mostly temperature-dependent in the electronis monitor system. If the oil temperature is low and the filter goes into bypass - no alarm. If the temperature is above the threshold and the filter goes into bypass - alarm. Therefore a dodgy temp sensor maybe occasionally indicating a higher than actual temperature combined with cold oil that puts the filter into bypass mode = nuisance alarm. The temp sensor function should have been one of the frist things the dealer looked at TBH.

 

[Nige]

The machine started having an issue (once in awhile and now more often) when going to reverse. The machine has to be shut down and restarted to get it to go. Tonight it feels like it’s trying to catch and then letting go. I did notice if you let it idle in gear sometimes it will catch. The Volvo also had a problem close to the same. I pulled some codes tonight as follows: E0049.3, E0155.0, 0673.02, 0585.02 and 0562.09. Don't have a clue what they are but we'll call Cat in the morning.

IMHO the 88 doesn’t have the wheel power the 350 did when pushing loads but I'd still rather have the 88. When the machine is pushing real hard in 1st you can hear and feel the power being reduced (by the computer I'm guessing) (maybe to reduce wheel slip?). The 88 is a little harder for an old fart like me to get in because the arm rest/steering controls don't move very far. The cab is quiet enough and comfortable. The mirror on the left side should have been mounted in another place because it the door is opened too far it hits the mirror you'll have to get back out and readjust it. < is about the only complaint other than the shifting problem which I'm 100% sure Cat will cure.

Simple things first, and I know this post is from a while back. There should be a rubber stop assembly to prevent the door hitting the mirror. Maybe it got left out when the reapir work was done to the cab roof after the loader hit the bridge while being transported to the job site..?

Fault Codes
562.09 - Cat Monitor System
585.02 - Transmission Output Speed Sensor #1 (there are 2 sensors)
673.02 - Transmission Output speed Sensor #2 (well golleeeee, do we see a pattern here?)
02 - data erratic, intermittent, or incorrect
09 - control not receiving expected information (I would guess from the transmission speed sensors in this case)

I would suspect a harness connector fault, maybe something as simple as a plug not fully home in a socket.

Event Code E049 is a Coasting in Neutral Warning - naughty, naughty.
Event Code E155 is a High torque converter outlet oil temperature - again naughty, naughty.

Talking about the "wheel power" of the modern generation of loaders, it is the electronics telling the engine what to do when it's detected that the loader is in the pile digging. All the larger loaders from 980 upwards work this way as far as I'm aware. Check out the diagram below.


At 1800 RPM the converter can absorb all the torque that the engine can produce, leaving nothing for operating the hydraulics. However if you look at 1200 RPM the engine actually produces more torque than at 1800, the "Torque Rise" all engine manufacturers famously quote.
If the loader is in 1st gear forward, the bucket is on or almost on the floor the floor (as detected by the boom angle sensor), and the ground speed is less than 1mph the "Dig Strategy" is activated. The engine is commanded to go to 1200RPM which in 1st speed should be sufficient to keep the machine moving into the material. At this RPM the converter can only absrob a percentage of the engine power, leaving the rest to run the hydraulics. A lot of operators who've never run the system before equate this to the engine "lacking power" where in actual fact it's the engine doing exactly what it needs to to produce an optimum power balance between the converter and the hydraulic system.

 

[JDOFMEMI]

NIge

A little off topic question for you here. Since you just educated us on the operation of the loader, can you tell me if the wheel dozer version does the same thing with the engine speed when pushing, or is it set up different because it is supposed to push most of the time, unlike a loader only pushing hard part time?

 

[Nige]

Jerry, which model of wheel dozer are you talking about, specific to a Serial Number prefix if you have one..?

 

[kshansen]

Plugged filter alarms are mostly temperature-dependent in the electronis monitor system.
<snip>
>The temp sensor function should have been one of the frist things the dealer looked at TBH.

Well I can't blame the dealer as I was the one trying to trouble shoot this problem. One problem I was having is how intermittent the problem was and the fact they did not want to stop production for trouble shooting. I did not see anything in the service manual indicating a connection with oil temp and don't think it ever gave the "false" warning when machine was cold. I did measure the pressure drop across the trans filter and it was well below the actuating point so I was confident that the warning was a false one.

 

[Nige]

First up there will be nothing in the Service Manual regarding that AFAIK. Maybe their should be. It's all tied up in the Monitor System software. I only know about it because I've worked with the larger machines that use a much more sophisticated Monitor System called VIMS and in system that you can actually get into the software and see exactly what value will actuate and deactuate any particular alarm.

I'm sure you can see the idea. If Cat put a spring that was so strong in the bypass valve to prevent it opening with cold oil then cranking the engine up in the morning at 20 below and then going straight to High Idle would immediately turn the filter element inside out. So the spring has to be suitable for "normal" operation and something has to be done about nuisance alarms when the machine is cold. If the filter is bypassing with cold oil you don't want the alarm sounding every time you rev the engine up. Therefore in order to generate an alarm both the temperature must be above X degrees (normally 60-65 DegC) and also the bypass valve switch contacts must be closed indicating that the bypass valve is open. That's always one good reason to allow the systems a few minutes to warm up on a cold morning before loading them.

I think what you most likely had was a temperature sensor that had not failed completely (would have been better if it had TBH) but was generating varying temperatures, some genuine, some not. If at some time it indicated more than the threshold temperature and the filter bypass valve happened to be open at that same moment the machine would throw a plugged filter alarm. From the sounds of it the temp sensor was dodgy because replacing it fixed the problem.

 

[kshansen]

I'm sure you can see the idea. If Cat put a spring that was so strong in the bypass valve to prevent it opening with cold oil then cranking the engine up in the morning at 20 below and then going straight to High Idle would immediately turn the filter element inside out.
<snip

I think what you most likely had was a temperature sensor that had not failed completely (would have been better if it had TBH) but was generating varying temperatures, some genuine, some not. If at some time it indicated more than the threshold temperature and the filter bypass valve happened to be open at that same moment the machine would throw a plugged filter alarm. From the sounds of it the temp sensor was dodgy because replacing it fixed the problem.

I know about the inside out filter deal. We had some Terex trucks with Allison trans. that at least once each winter some driver would get into it too soon, pushed the cans right down over the center bolt. I think that is what they call hydro-forming!

The way I finally found the bad sensor was I finally got access to the lap top with Cat ET on it, only had one lap top for several plants all across the state, but that's another story. Using the Cat ET I found logged events for trans. temp but not plugged filter. This got me looking in the right direction. I knew I was getting close when all I had to do is touch the wires coming out of the sensor to turn the warning light on or off.

 

[JDOFMEMI]

Nige

My question above was just a general one, not machine specific. I was mainly thinking of comparing to the same size machoine as what you posted the curve for the loader, so I would say 834H, to get a comparison.

Your answer above just got me curious is all.

 

[Nige]

Jerry, I just wanted a bit of time to check, before opening my mouth and putting my foot in it - not for the first time I hear you say ...!!

There is no similar system for the Wheel Dozers, only the rimpull control that is either under the control of the left pedal or the rotary switch on the RH dash panel. The electronic Rimpull control works in just the same way as the old VCTC converter control on the old 992's. It limits the pressure to the TC Impeller clutch and so slips the input side of the converter.

KSH - as you have discovered ET is your friend, although in a lot of cases you can actually pull Diagnostic Codes using the Monitor System on the machine if you don't have a laptop with ET immediately available. It's well worth knowing how to do it just in case you are ever confronted with a similar situation again. If you're playing with electronics on a regular basis then Cat Special Instruction REHS0126 contains a list of all the Diagnostic Codes and Failure Modes.

 

[Per Eriksson]

Caterpillar Bulletin TIBU3671 describes your problem with the bucket.
The makeup valve and pump can't provide enough oil to keep the cylinder filled with oil while dumping a load.
It does mention a new software being tested that will allow the hydraulics to fill the cylinder if the control is held in dump position a few seconds after reaching the dump stop.

So make sure you have the latest implement software to begin with and if that doesn't help there's a rework avaliable to fit a regeneration valve for the bucket function.
See Service Magazine SEPD0990 and special instruction REHS4199 for more info.
If your machines already have this valve installed it can clearly be seen since it's mounted directly on top of the bucket cylinder.

 

[Nige]

I hadn't dug deep into the system for the documents Per refers. If you need them then PM me with an e-mail address that I can send them to.