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Topic: Vacuum pump installation (Read 212 times) previous topic - next topic

Vacuum pump installation

So sometimes the simplest things can make me scratch my head in puzzlement.
I ordered a dorman 904-214 vacuum generator based on recommendations of people in this forum to replace my aging and rusted out vacuum generator as possible fix for my dash temperature controls not working properly.
And I'm a little puzzled with one of the connections. There was an airline going to one side of the vacuum generator and on the foretravel model there is a push in connector for that line. On the dorman there is only a plastic piece with a lip on the end. I'm not familiar with that type of a fitting.
So questions are number one what's that fitting for and how do I connect an airline to it?
Number two why is there an airline going to the vacuum pump on our coaches? if it's just producing vacuum for the dash gauges what's it doing with  compressed air going to it?

'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Vacuum pump installation

Reply #1
You no longer need the air line at all, you'll want to cap that off behind the step. The old vacuum generator used that airline to create the vacuum but now you'll basically do that with an electric motor instead.

It should just be two 12v wires to the new pump and one vacuum line coming out of the accumulator tank.

Here's a write up on it: Dash Air Stuck on Defrost/Vacuum Pump Replacement

Also, I highly recommend you attach the new pump to a board like Keith did, before affixing it to your coach. That will make life much easier.
2001 U320 4010

Not all that wander are lost... but I usually am.

Re: Vacuum pump installation

Reply #2
You no longer need the air line at all, you'll want to cap that off behind the step. The old vacuum generator used that airline to create the vacuum but now you'll basically do that with an electric motor instead.

It should just be two 12v wires to the new pump and one vacuum line coming out of the accumulator tank.

Here's a write up on it: Dash Air Stuck on Defrost/Vacuum Pump Replacement

Also, I highly recommend you attach the new pump to a board like Keith did, before affixing it to your coach. That will make life much easier.
Thanks Elliot. That's exactly what I needed to know. I'll finish the install tomorrow.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Vacuum pump installation

Reply #3
Bob there are 2 fittings one is the vacuum the other is the exhaust you can't cap it off.  you can connect a hose to it with a small brass filter to keep mud daubers from filling up the hole
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Vacuum pump installation

Reply #4
Okay just to finish out the thread I installed it yesterday. I did not put it in the same place but where my passenger side headlight would be. It's mounted on a small piece of fiberglass shelf.
Definitely had a big air leak from the hose that I removed from the previous one so I shoved the screw in there and bent it over twice and zip tied it for now. It stopped the leak otherwise I wouldn't have got the safety stands out.
Haven't tested it yet. I suspect that my issues with the dash air and heater controls have to do more than just to vacuum pump but I'll see in a couple days on my drive back to the US.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired