Bryce C
DFW
My RPM gauge gets weird when I turn the water pump on. It works perfect when the tm is running at low, medium, or high. But when I turn the main water pump on the gauge maxes out and no longer reads the rpms of the machine.
Gauge goes crazy
- Thread starter Bryce C
- Start date
When you say waterpump and main water pump you loose me. I have no idea what your talking about. Transfer/ supply/auxiliary supply pump??? Those terms would make me think that you carry water and is supplied to the machine by this pump . Where as ,main/pressure/ high pressure or name ie:cat/general/ hipro would make me assume that you're talking about the pump that supplies soulition to your wand . Then there's the wastepump i dont know what else you can call that one but waterpump pump and main pump can be interpreted differently . But with that said i don't know about your machine specifically but generally speaking the tachometer has a magnetic pickup and so machines mount this pickup on the main pressure pump and attaches a magnet on the back ( pump side) of the clutch pulley that pulley generally speaking again , turns much slower than engine or blower and is compensated electronically with a setting button on the tach. Perhaps with the work you have recently been doing in that general area youve inadvertently knocked this outa whack . I tack my machine off the driveshaft and measure blower speed below is a picture of mine yours will probably look different but worhs the same ill try to find another picture and edit with it couldn't easily find it but Google says the location is on the blower drive pulley
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Bryce C
DFW
Thanks for setting me straight with the lingo Dwain. I didn't see anything like the magnetic pickup near the blower pulley, maybe it is on the high pressure pump. Now that I know how it operates and what it looks like I'll be able to spot it next time I uncover the power pack and check things out. Its happened a couple times now where the machine shuts down for no reason at all. Then it just starts right up and continues running fine. I wonder if the tachometer going far enough out of whack could've triggered a safety mechanism.
It's really cool slowly demystifying this machine and seeing how it all works. I really like this CDS 4.8. Such a cool design...
Jim Pemberton
MB Exclusive.
- Joined
- Oct 7, 2006
- Messages
- 12,673
- Name
- Jim Pemberton
When I first became aware of your troubles with the unit you purchased, I nearly texted you to recommend that you get it to a nearby service center.
I'm glad that I didn't....
What Dwain has so unselfishly shared with you has saved you thousands of dollars in labor charges, and what you've done by learning to do this work on your unit yourself, will save you thousands more, plus days of downtime.
I am amazed and the amount of in depth knowledge Dwain has, and even more impressed with his selflessness.
Bryce C
DFW
Thanks Jim. Wise words. Dwain is both seriously knowledgeable and immensely charitable. And here I am an undeserving goofball with grace pouring out on him. With the help of Dwain and others here I have gone from barely knowing how to turn this thing on to having a decent working knowledge of it in a short period of time. Trial by fire, I thank God for you all.
Jim about going to a local service center... I did! The folks you know very well that you and I have talked about. They said no, we won't work on it! After I drove 2 hours round trip twice! I really just wanted them to get it in good working order so I could learn the basics and figure out how to repair and maintain it later. When the engine idle wasn't correct those guys said they won't touch that part of a pto style system
So Robert that you introduced me to at MF and Dwain here helped me get that fixed promptly. Then the rest of the needed repairs followed 1 after the other, with Dwain saving my arse, and teaching me precious knowledge.It's working well now. Occassionally the machine shuts down without having tripped any recovery tank or water box sensors. I am hoping it has something to do with the tachometer when I look into that soon. Otherwise turning it off and rebooting it seems to get it working fine, then it runs as long as I need it to.
Does your machine completely shut down or does the van engine drop to idle?Thanks Jim. Wise words. Dwain is both seriously knowledgeable and immensely charitable. And here I am an undeserving goofball with grace pouring out on him. With the help of Dwain and others here I have gone from barely knowing how to turn this thing on to having a decent working knowledge of it in a short period of time. Trial by fire, I thank God for you all.
Jim about going to a local service center... I did! The folks you know very well that you and I have talked about. They said no, we won't work on it! After I drove 2 hours round trip twice! I really just wanted them to get it in good working order so I could learn the basics and figure out how to repair and maintain it later. When the engine idle wasn't correct those guys said they won't touch that part of a pto style system
It's working well now. Occassionally the machine shuts down without having tripped any recovery tank or water box sensors. I am hoping it has something to do with the tachometer when I look into that soon. Otherwise turning it off and rebooting it seems to get it working fine, then it runs as long as I need it to.
Bryce C
DFW
Van engine just suddenly drops to normal van idling of about 600 or so rpm. But the machine stays on. Good question, I stated the issue incorrectly.
I thought maybe the OBD plug from thr throttle controller came loose. I wrapped a piece of electrical tape around it to make sure it is snug and it is still occassionally doing it. All the connectors on the throttle controller itself are snug too.
My machine does that every once and a while about once every two weeks or so. It has to do with the throttle controller. I think it loses momentary contact some how with the engine control module or ground/brake set.
Thats where the led lights on the controller would come on handy. Till you restart the controller will self diagnose. In my case its buried deep in my dash and not easy to see.
