2004 MXZ 800 HO needs choke to run

Highmaintenence

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Thanks all...will be working in the sled this weekend. Maxwell, how do you attach the 9V bat to the DPM? I'm not the most mechanically inclined...sure appreciate your help. My buddie say THANKS!!

Cheers
 

DRD

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A non dpm machine runs s way larger main jet something likme 10 to 13 sizes. So it would run like crap above half throttle I would think. Someone correct me if I'm wrong tis what I have discovered with a non dpm machine I had at the shop last year

Why would a non DPM sled need such a huge jet?
The DPM can only lean out, not enrichen the mixture. A DPM sled comes jetted (normally) for sea level and -30C or -40C (something close to that I'd have to look in the manual to be sure). The DPM then leans it out as needed, mostly based on atmospheric pressure ( altitude) and temperature.
As discussed if the DPM fails it goes pig rich by design. We all know what would happen if they failed lean.
 

maxwell

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Why would a non DPM sled need such a huge jet?
The DPM can only lean out, not enrichen the mixture. A DPM sled comes jetted (normally) for sea level and -30C or -40C (something close to that I'd have to look in the manual to be sure). The DPM then leans it out as needed, mostly based on atmospheric pressure ( altitude) and temperature.
As discussed if the DPM fails it goes pig rich by design. We all know what would happen if they failed lean.

That's what I meant. Smaller for the non dpm machine and larger for the dpm machine had that backwards
 

maxwell

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Thanks all...will be working in the sled this weekend. Maxwell, how do you attach the 9V bat to the DPM? I'm not the most mechanically inclined...sure appreciate your help. My buddie say THANKS!!

Cheers

shoud be a red and a black wire coming from the dpm manifold.

unplug it from the computer.

then you will need to use 2 peices of small wire or maybe a paperclip to insert into the plug to use the 9v battery
 

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Why would a non DPM sled need such a huge jet?
The DPM can only lean out, not enrichen the mixture. A DPM sled comes jetted (normally) for sea level and -30C or -40C (something close to that I'd have to look in the manual to be sure). The DPM then leans it out as needed, mostly based on atmospheric pressure ( altitude) and temperature.
As discussed if the DPM fails it goes pig rich by design. We all know what would happen if they failed lean.

DPM only fails rich when there is a leak, or if the solenoid seizes open...
What if it seizes shut? food for thought..

It's not the DPM fellas, He has to choke, which means is acting lean.

I highly doubt it is the DPM. It sounds like the motor is starving for fuel.
You mention it does not run... does it idle? or is this symptom at throttle up?
 

maxwell

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DPM only fails rich when there is a leak, or if the solenoid seizes open...
What if it seizes shut? food for thought..

It's not the DPM fellas, He has to choke, which means is acting lean.

I highly doubt it is the DPM. It sounds like the motor is starving for fuel.
You mention it does not run... does it idle? or is this symptom at throttle up?

and if its starving for fuel whats the one component that restricts that?

im not saying its the dpm

just want him to eliminate it so we can move on haha
 

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Fuel filter, Fuel pump..
I had problems with the check valves for the fuel tank on my REV.
That may be it... now that I think of it. Does it run better when you open your fuel cap?
I drilled out the blue check valve, routed a long clear line... forward, to the left, and up higher than tank height, and then to the right, then back/. and ended up to the back behind the seat with the line (over tank and down thru tunnel). No matter what you did, it never poured fuel out when you were tipped, or pointing up or downhill. You have to do this because it will drain out from the tank on a REV.

Anyways, I had issues with mine when it got warm outside., The check valves...

Thanks for the brainstorm Maxwell!
 
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