Boxxer 421 engine issue. | TruckMount Forums #1 Carpet Cleaning Forums

Boxxer 421 engine issue.

Sir ramic

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Hi guys..

Just would like some idea of this issue. The machine was running fine today, had a problem with the water flow. The machine cut out and once restarted will not throttle up and sounds awful.

There are sparks on both plugs, I’ve checked filters, I think it can do with descaling.

It doesn’t make a difference if in heat mode, or with the pump clutch on off.


Any ideas would be much appreciated thanks
 

PistolPete

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Hi guys..

Just would like some idea of this issue. The machine was running fine today, had a problem with the water flow. The machine cut out and once restarted will not throttle up and sounds awful.

There are sparks on both plugs, I’ve checked filters, I think it can do with descaling.

It doesn’t make a difference if in heat mode, or with the pump clutch on off.


Any ideas would be much appreciated thanks
Fuel delivery issue?
 

Sir ramic

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Fuel delivery issue?
I’m going to have a look properly when I’m back home, pull out the new plugs check again. Tried running in divert mode, with the air filter off. Manually put the ram in the upright position.

It did effect the revs but still not right. After needing a new rectifier regulator, ignition coils and niggly problems here and there, I’m half tempted to fit a new engine. Rebuild the old one and have as a spare. I think the engine is 2002. At least it should be a while before more problems arise.
 

Sir ramic

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The problem is I’m starting the business on weekends as I lay tile through the week. It goes wrong on the weekends and everywhere is closed ha ha
 

Sir ramic

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Here is what I’ve done so far, pulled the new plugs and they were fouled. I switched the plugs, run again and checked the plugs fouled again.

When I hold the ram up, machine throttle up more, once I release it bogs down again. So maybe a blocked heat exchanger?
 

wandwizard

Randy Dockins
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Descaling is a good first step. I've used just a gallon of white vinegar on many occasions, but if you have a bad scale build-up descaler might be better. I would put one whole gallon of vinegar in the machine's tank. Use a short hose to recirculate it back to the tank for a few minutes at full throttle. Then turn the machine off and let it sit for a couple of hours. Hook your water up normally and remove both the caps for the orifices on the front of the machine and make sure the filter in those are clear. I normally just crank the machine up and let it flush out the orifices a few seconds.

If the orifices get clogged, normally it will be the high-pressure one that is smaller, that will cause the machine to overheat super quick and it will shut itself down automatically. More often than not that is the reason the machine shuts down while you're working. Sometimes it may be necessary to take an Allen wrench and actually remove the orifices and make certain they're clean. Be sure not to cross up the 2 orifices. Best to just take one out at a time. If needed soak in some CLR for a little while.

If the machine is still giving trouble after you descale and clean the orifices you may have another issue, but this is what I'd do first. There is another possibility that I can think of, but you won't be able to take care of it yourself. Btw, are you using a water softener?
 
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wandwizard

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Here is what I’ve done so far, pulled the new plugs and they were fouled. I switched the plugs, run again and checked the plugs fouled again.

When I hold the ram up, machine throttle up more, once I release it bogs down again. So maybe a blocked heat exchanger?
The blocked finned heat exchanger for the blower could be the issue. I've only had that happen once and I've owned my machine since 2002 and have many thousands of hours on it. I had to take it in for service at Jondon and they soaked it in something like you do radiators. After they put it back on I had good heat again and it stopped the issues which were very similar to what you're experiencing. It won't make any difference whether you're in divert mode or not when this is the problem because the blower will create back pressure on the engine bogging it down as soon as you throttle up. Btw. I seriously doubt your new plugs are fouled. There is a chance that a small engine mechanic can help determine if it's something to do with the engine. He won't be able to help you if it's a clogged heat exchanger though. You'll be forced to go in for service unless you own a forklift.

One thing I can think of that might help is to remove the hose that joins the blower to the vacuum tank then see if the machine starts and runs. If it does you should know you have a clogged exchanger. Possibly just removing the waste tank lid would work.
 
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Sir ramic

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Descaling is a good first step. I've used just a gallon of white vinegar on many occasions, but if you have a bad scale build-up descaler might be better. I would put one whole gallon of vinegar in the machine's tank. Use a short hose to recirculate it back to the tank for a few minutes at full throttle. Then turn the machine off and let it sit for a couple of hours. Hook your water up normally and remove both the caps for the orifices on the front of the machine and make sure the filter in those are clear. I normally just crank the machine up and let it flush out the orifices a few seconds.

If the orifices get clogged, normally it will be the high-pressure one that is smaller, that will cause the machine to overheat super quick and it will shut itself down automatically. More often than not that is the reason the machine shuts down while you're working. Sometimes it may be necessary to take an Allen wrench and actually remove the orifices and make certain they're clean. Be sure not to cross up the 2 orifices. Best to just take one out at a time. If needed soak in some CLR for a little while.

If the machine is still giving trouble after you descale and clean the orifices you may have another issue, but this is what I'd do first. There is another possibility that I can think of, but you won't be able to take care of it yourself. Btw, are you using a water softener?

Thank you for the reply, I’ve taken of the orifices big and small. The small one was a little dirty but nothing much.

I checked the filter from the fresh water pump, that was clogged with white almost gravel looking stuff. I pulled it out and cleaned it.

I do use a water softener, I think? It’s a long cylinder type tube that I fill the water In threw. It then goes to the fresh water tank from there. I’ll have to discale the machine,
 

Sir ramic

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The blocked finned heat exchanger for the blower could be the issue. I've only had that happen once and I've owned my machine since 2002 and have many thousands of hours on it. I had to take it in for service at Jondon and they soaked it in something like you do radiators. After they put it back on I had good heat again and it stopped the issues which were very similar to what you're experiencing. It won't make any difference whether you're in divert mode or not when this is the problem because the blower will create back pressure on the engine bogging it down as soon as you throttle up. Btw. I seriously doubt your new plugs are fouled. There is a chance that a small engine mechanic can help determine if it's something to do with the engine. He won't be able to help you if it's a clogged heat exchanger though. You'll be forced to go in for service unless you own a forklift.

One thing I can think of that might help is to remove the hose that joins the blower to the vacuum tank then see if the machine starts and runs. If it does you should know you have a clogged exchanger. Possibly just removing the waste tank lid would work.
We’ve been out there this afternoon with the mechanic. Although he is a motorcycle mechanic. We switched the plugs and started the machine.

When I held the diverter ram up, the throttle would respond, when I release the ram it bogged straight away again. We then pulled the plugs again and fouled.

I spoke with a Truckmount manufacturer in the uk, and he said it’s more then likely the blower heat exchanger. He was the one asking me to lift the ram then throttle up. Then release again.

The problem I’ve got is that I’m the only person with one of these machines on the island I live, so taking it to mainland uk is a ferry ride and a logistical nightmare for me, as I’m starting this as a weekend business for now.

Two weekends ago I used it and the rubbers in the drive coupler failed, so I needed to change them. Luckily I had spares, and it was toward the end of the job.

Today I was only around quarter of the way through and had a load of tm all over the floor that I couldn’t then get up

She’s not happy with me, but I’m going back tomorrow.
 

Sir ramic

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The blocked finned heat exchanger for the blower could be the issue. I've only had that happen once and I've owned my machine since 2002 and have many thousands of hours on it. I had to take it in for service at Jondon and they soaked it in something like you do radiators. After they put it back on I had good heat again and it stopped the issues which were very similar to what you're experiencing. It won't make any difference whether you're in divert mode or not when this is the problem because the blower will create back pressure on the engine bogging it down as soon as you throttle up. Btw. I seriously doubt your new plugs are fouled. There is a chance that a small engine mechanic can help determine if it's something to do with the engine. He won't be able to help you if it's a clogged heat exchanger though. You'll be forced to go in for service unless you own a forklift.

One thing I can think of that might help is to remove the hose that joins the blower to the vacuum tank then see if the machine starts and runs. If it does you should know you have a clogged exchanger. Possibly just removing the waste tank lid would work.

I’ll try now and take the hose off and see if that works. Also thank you very much for your help, much appreciated
 

Sir ramic

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I’ll try now and take the hose off and see if that works. Also thank you very much for your help, much appreciated

I’ve taken the hose off from the blower to the waste tank, no difference. Still the same.
 

wandwizard

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Thank you for the reply, I’ve taken of the orifices big and small. The small one was a little dirty but nothing much.

I checked the filter from the fresh water pump, that was clogged with white almost gravel looking stuff. I pulled it out and cleaned it.

I do use a water softener, I think? It’s a long cylinder type tube that I fill the water In threw. It then goes to the fresh water tank from there. I’ll have to discale the machine,
You'll need to get some water hardness test strips and learn to regenerate your water softener or you will have lots of future problems to look forward to in addition to the one you're having now. I don't know what softener you have now, but you'll have to find out and learn how to regenerate the softener periodically. If you're only working on the weekends you shouldn't have to do it near as often, but it probably needs doing asap. I purchased my test strips on Amazon. You may have to find another source. All you need for regeneration is cheap rock salt for water softeners.

I would add one other thing I think is important, but may be hard for you to get. I use a Devastator filter which use a 5 gallon bucket paint strainer to capture stuff before it enters the tank. Just the tank filter that comes with the machine is not sufficient to filter out a lot of the particles that get into the tank. I am not sure, but I think this has really helped make a difference in keeping my blower heat exchange cleaner for a number of years now.
 

wandwizard

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We’ve been out there this afternoon with the mechanic. Although he is a motorcycle mechanic. We switched the plugs and started the machine.

When I held the diverter ram up, the throttle would respond, when I release the ram it bogged straight away again. We then pulled the plugs again and fouled.

I spoke with a Truckmount manufacturer in the uk, and he said it’s more then likely the blower heat exchanger. He was the one asking me to lift the ram then throttle up. Then release again.

The problem I’ve got is that I’m the only person with one of these machines on the island I live, so taking it to mainland uk is a ferry ride and a logistical nightmare for me, as I’m starting this as a weekend business for now.

Two weekends ago I used it and the rubbers in the drive coupler failed, so I needed to change them. Luckily I had spares, and it was toward the end of the job.

Today I was only around quarter of the way through and had a load of tm all over the floor that I couldn’t then get up

She’s not happy with me, but I’m going back tomorrow.
You might consider getting a good portable for backup. Honestly, if I didn't have a place like Jondon I'd be sunk on occasion. Some of the things on the Boxxer can be pretty complicated to fix especially if you don't work on truckmounts every day as they do. Sometimes even they have trouble fixing stuff on it. I still can't rule out the clogged vacuum heat exchange, so you may have to take it in no matter what. Quite often the manual will give good guidance on what's wrong if you read the troubleshooting section carefully.

There have been times I've been tempted to strip this machine down and go with some external way to heat the water. 75% of the problems with the machine have been due to what's been put in it to provide hot water and I'd say the other 25% have been engine related. I put a new engine on mine last September. My original engine lasted from 2002 to 2018 so I guess I got my money's worth out of it.

By holding the ram up are you meaning the actuator that looks kind of like a shock absorber that opens and closes the diverter? That thing is supposed to stay up all the time unless the diverter switch on the front panel is turned on. If it is not working correctly you can take some kind of wire and wire it to stay in the open position until you can get this fixed. Is the diverter switch working ?
 
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Sir ramic

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You'll need to get some water hardness test strips and learn to regenerate your water softener or you will have lots of future problems to look forward to in addition to the one you're having now. I don't know what softener you have now, but you'll have to find out and learn how to regenerate the softener periodically. If you're only working on the weekends you shouldn't have to do it near as often, but it probably needs doing asap. I purchased my test strips on Amazon. You may have to find another source. All you need for regeneration is cheap rock salt for water softeners.

I would add one other thing I think is important, but may be hard for you to get. I use a Devastator filter which use a 5 gallon bucket paint strainer to capture stuff before it enters the tank. Just the tank filter that comes with the machine is not sufficient to filter out a lot of the particles that get into the tank. I am not sure, but I think this has really helped make a difference in keeping my blower heat exchange cleaner for a number of years now.
I’ll see if I can source one of these. Yes there is no Jondon here. My round trip because it’s a commercial van is around £700, just for the ferry. I’ve then got to get to them from the boat. I’d have to stay over there too, it’s a nightmare.

The filter in the tank was pretty clogged up last week. But all cleaned up, and a little bag in the waste tank too.

Maybe I switch to a better method like you say, maybe I can put an inline filter for when I’m using it.

I was going to get a custom machine made for me, like the judson just engine pump and blower, then heat from a little giant or similar.

I wanted to minimise the issues around the heat exchanger for these reasons.

I just seem to be putting more money in, with little return due to many issues I have.

I mean I get to a job and panic and just hope it lasts the job ha ha.
I’ve got the manual with me now and just going to go thoroughly through it.

Getting a forklift is no issue. I did think about a backup portable the mytee etm.
 

PistolPete

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Do a Judson on it.
Get rid of everything except pressure pump and blower.
2 shut down circuits, oil pressure and waste tank float switch.
Add propane or diesel heater.
 
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Sir ramic

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Do a Judson on it.
Get rid of everything except pressure pump and blower.
2 shut down circuits, oil pressure and waste tank float switch.
Add propane or diesel heater.
Thanks, this might be what I end up doing. I can’t believe the hole thing needs to come out to get to the blower heat exchanger.

They are not cheap to replace either are they. So I think you are maybe onto something here. Keeps it super simple, can get rid of quite a bit of stuff on there.

It has to come out anyway so maybe get it out and go from there.

If I take it out, leave it soak over night. The 30 mins in a ultrasonic tub. If I’m lucky it may clear. If not around £1500 to replace,
 

wandwizard

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Thanks, this might be what I end up doing. I can’t believe the hole thing needs to come out to get to the blower heat exchanger.

They are not cheap to replace either are they. So I think you are maybe onto something here. Keeps it super simple, can get rid of quite a bit of stuff on there.

It has to come out anyway so maybe get it out and go from there.

If I take it out, leave it soak over night. The 30 mins in a ultrasonic tub. If I’m lucky it may clear. If not around £1500 to replace,
One thing I have to say on the positive note of my Boxxer 421 is that in getting near 17 full years of service neither of my heat exchanges have ever leaked or had to be replaced. Chances are if you can get a forklift like you said and can manage to get that thing off and soak it and reinstall it you should be in good shape.

The problem with the vacuum heat exchange is external, not internal. That is why I tend to think that anything you can do to filter the air before it goes into the waste tank will help over the years of use. All I can say about that is it seems to have worked for me. You still need to make sure the heat exchanges are descaled on the inside. I find with a water softener I don't have to descale the machine very often at all and white vinegar normally does the trick. If I ever feel the scale is really bad I would use a regular TM descaler. I don't know how long Jondon normally soaks those things but seems like they were soaking mine a good while when working on my machine. It made an amazing difference. The thing worked like new after that.
 
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PistolPete

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Just for my knowledge, I don't understand how a clogged HX on the vacuum system causes engine performance issues?
What am I not getting?
 

wandwizard

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Just for my knowledge, I don't understand how a clogged HX on the vacuum system causes engine performance issues?
What am I not getting?
The vacuum blower which is directly coupled to the engine on the Boxxer 421 exerts a tremendous amount of force and has to pass through that finned heat exchange. That gives the machine about a 50 to 70-degree temp rise. When those fins get clogged up from years of use it causes what they refer to as back pressure on the engine so the engine will bog down as you throttle up the rpms. When it happened to me I thought my engine was about to blow up. Removing and soaking the vacuum exhaust heat exchange did solve my problem and restored my water heat back to like new. Technically those finned heat exchanges are supposed to be removed and soaked about every 2,000 hours, maybe less. I have well over 8,000 hours on my machine and only did this one time in almost 17 years. I at least partially attribute that to using the Devastator filter. I could be wrong about that, but I don't think so. I bet it's been over 5,000 hours easily since I had my blower exchanger off.
 
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PistolPete

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The vacuum blower which is directly coupled to the engine on the Boxxer 421 exerts a tremendous amount of force and has to pass through that finned heat exchange. That gives the machine about a 50 to 70-degree temp rise. When those fins get clogged up from years of use it causes what they refer to as back pressure on the engine so the engine will bog down as you throttle up the rpms. When it happened to me I thought my engine was about to blow up. Removing and soaking the vacuum exhaust heat exchange did solve my problem and restored my water heat back to like new. Technically those finned heat exchanges are supposed to be removed and soaked about every 2,000 hours, maybe less. I have well over 8,000 hours on my machine and only did this one time in almost 17 years. I at least partially attribute that to using the Devastator filter. I could be wrong about that, but I don't think so. I bet it's been over 5,000 hours easily since I had my blower exchanger off.
I guess I'm having a hard time visualizing the HX set up.