What is this on my gas tank?

[kellyfettes]

88 holiday rambler imperial 34 ft. This is leaking gas. What is it?? In the yellow circle. Does it just cap off or is there a supposed to be a line to something? To the generator?? It is attached to the gas tank. I just noticed the smell of gas today. Had the rv delivered on Saturday and didnt notice anything leaking. The red arrow is pointing to the left side of rig. The blue arrow is pointing to gas tank. The green arrow is pointing towards front of rig. This is behind the back tires.

 

[Gary RV_Wizard]

Hard to guess.  Maybe a port to allow connection to a gas genset?  Or simply a tank drain plug?

If I'm understanding the arrows, that outlet is part way up the side of the tank? That would be consistent with a generator port, but maybe you already have one of those?

 

[kellyfettes]

I dont see anything else coming from the gas tank. I tried to trace back from the generator and those lines must be up in the I- beams. I just dont see anything close that it could connect to. I am thinking it is for the generator tho. Until i get it figured out, can I just cap it off??

 

[darsben]

It could be a fuel pressure regulator. I cannot get a good view but post a link. IF your rig has a Chevy 454 Then I am more certain
https://www.summitracing.com/parts/hly-12-803/overview/

 

[kellyfettes]

Darsben, what is sposed to go on the threaded end? Where the gas is coming out?

 

[darsben]

As I said I cannot get a good look from the picture you submitted, but if it is the pressure regulator then it would have an Allen type female fitting on the inside allowing the pressure to be adjusted.
I had to change mine when it leaked

This picture I link to gives a good view of a new one. It can be rotated 360 degrees
https://www.summitracing.com/parts/hly-12-803/overview/

 

[kellyfettes]

Darsben. Thank you for the info, I do believe that is what it is. I am going to take it apart tomorrow and see if I can just order a repair kit. Thank you again.

 

[John From Detroit]

Can you back off a few feet and show us more of the tank???

If that is normally covered by a yellow cap its the fill port
If not.. I'm at a loss

 

[kellyfettes]

John, I think it is the fuel pressure regulator. I found a video on youtube that showed the exact thing.

 

[catblaster]

As I said I cannot get a good look from the picture you submitted, but if it is the pressure regulator then it would have an Allen type female fitting on the inside allowing the pressure to be adjusted.
I had to change mine when it leaked

This picture I link to gives a good view of a new one. It can be rotated 360 degrees
https://www.summitracing.com/parts/hly-12-803/overview/

    Darsben is right, it is a fuel pressure regulator. What you seeing are threads with a hole in the middle, that is the allen headed adjusting screw. The diaphragm has ruptured and allowing fuel to get on the atmospheric side of the diaphragm. They can be rebuilt but much better to just buy a new one and not have to deal with broken screws or stripped holes. Quick Fuel make a regulator that looks exactly like the one Darsben linked to as a Holley. Everyone has a preference but it is my belief that the quick fuel has a better diaphragm installed, also cost a little more.

 

[darsben]

New is only $32.00 plus shipping. and is usually a direct swap. How much less can the rebuild kit be that it would pay (time wise) to rebuild

 

[kellyfettes]

Thanks for all the help. I ordered a rebuild kit as I only have about 6 inches of room to work between the gas tank and the water tank. There isnt any slack in the fuel line that leads to the regulator so I cant pull it out to get the new one on the gas line. I sprayed the screws with cleaner and they came right out. The kit should be here in 2 days.

 

[darsben]

For future reference where did you order a rebuild kit?
The original replacement the Holley 12-807 is not recommended for ethanol. the replacement QFT 35-1100 is ethanol safe.