CDS rpms won't come up

gimmeagig

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Joined
Mar 25, 2007
Messages
727
Location
Hayden,Idaho
Name
Roxy
I have a 1999 CDS machine and recently it's been happening that when I turn on the machine the revs are very low. When I put my hand over the vacuum intake it will rev up. I do that a few times and eventually, when I let go , the machine will run as it should.
Sometimes I have to open the hood and fiddle with the pods. It does not seem like the linkeage is sticking, I think it is something inside the pod. I hear a clicking sound and then it works again.
So far I have been able to get the machine running every time, but it is getting worse.
I tried to reproduce that for my mechanic but of course when I take it there, it works perfectly.
Do I need to replace the pods? I think they have them at Napa for a lot less that Hydramaseter sells them for. Are they the same or is there a difference?
 

gimmeagig

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Joined
Mar 25, 2007
Messages
727
Location
Hayden,Idaho
Name
Roxy
I've been to LPM ( my Truckmount repair place) twice now to show the mechanic what's happening, but every time I'm there the machine works perfect.
I have sprayed some electronic component lubricant into the vacuum hose that is attached to the primary pod. I followed it up with some air spray. Today the machine has worked fine.
 

gimmeagig

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Joined
Mar 25, 2007
Messages
727
Location
Hayden,Idaho
Name
Roxy
I replaced the hoses. When the low RPMs happen I fiddle around with the linkage at the pod eventually I hear some type of clicking/snapping sound and then it's all good again. But I have not been able to reproduce that for my mechanic.
 
Joined
Jan 21, 2008
Messages
790
Location
Colorado Springs
Name
Brad Gouveia
The pods Napa sells are the same and much cheaper. I can try swap the vac lines around. One pods brings the RMPS up and the other increase the RMP under load.
Swaping the vac lines should tell you if one is bad or not. Might have to adjust the pods a bit after swapping.
 
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gimmeagig

Member
Joined
Mar 25, 2007
Messages
727
Location
Hayden,Idaho
Name
Roxy
The pods Napa sells are the same and much cheaper. I can try swap the vac lines around. One pods brings the RMPS up and the other increase the RMP under load.
Swaping the vac lines should tell you if one is bad or not. Might have to adjust the pods a bit after swapping.
Do you know by any chance what the Napa part number might be? I don't know if there are different types of pods with different ratings, or if they are all the same
 

gimmeagig

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Joined
Mar 25, 2007
Messages
727
Location
Hayden,Idaho
Name
Roxy
Might see if there is a electronic speed control you can install. All else fails use a stick propped on the gas petal : )
I have a stick that I have cut to the right length for that purpose in my van already, just in case. Haven't needed it yet, but you never know....I hate these intermittent problems.
 
Joined
Jan 21, 2008
Messages
790
Location
Colorado Springs
Name
Brad Gouveia
i just know it is a vac pod they use on old cars for cruise control. I am pretty sure if they search for vac pods they should be able to find it. I think they only make one.
 

gimmeagig

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Joined
Mar 25, 2007
Messages
727
Location
Hayden,Idaho
Name
Roxy
here's the latest..Since I sprayed lube into the vac line , the machine acts a little differently. Now it starts out on a really low idle but within 15 to 30 seconds of running like that the idle will come up to normal without me doing anything. I can live with that.
 

Doug Rice

Supportive Member
Joined
Feb 28, 2011
Messages
425
Brad, if you have a hydramaster CDS check the little blue solenoid that has 2 wires and a vacuum line going into it. It's right in front of the pods and about 1" cube. Make sure you have a good connection on those 2 wires.
 

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