Tank vent on 2 hose tank for QD11

[Rick Robbins]

I read where the tank pressure is supposed to be about 2-3 lbs. I checked mine and it gets to over 7-8 lbs. Of course the engine has problems running because of a rich fuel mixture, but I need some info
on how I can fix the tank relief valve. I don’t even know where it’s located in the tank top.
I know that the tank is not the original high boy, but it is a 2 hose tank from a later model
Any suggestions would be appreciated. I was considering converting to a single hose set up, but this would be easier (I think) at this point.
Rick
P.S. I just read some info that the tank pressure SHOULD be around 8 lbs. The gauge I used only went to 8 lbs and I don’t know if it actually went higher. Maybe I’m barking up the wrong tree.
what does the tank vent look like, how do I get to it and what’s a good way to test if it’s working properly?

• This topic was modified 4 years, 5 months ago by Rick Robbins.
• This topic was modified 4 years, 5 months ago by Rick Robbins.
• This topic was modified 4 years, 5 months ago by Rick Robbins.

[frankr]

Pressure relief valve is items 32, 33, 34. I don’t think I’ve ever seen one fail to release. Plenty of them fail to hold pressure though.

[Rick Robbins]

Thanks for the response frankr. I thought the pressure might have been my problem since I mistakenly measured 7-8 lbs, thinking it should be 2-3 lbs. I might try and take the tank top off and see the relief valve condition. Maybe I’ll just keep the pressure system and see if I can figure out why the motor is running rich.

[garry-in-michigan]

The usual problem with running rich is the cork float in the carburetor loosing buoyancy or the float valve leaking. A fuel pump being push/pull may actually increase the pressure depending on the design.There limit is crank case pressure and shed not be less than 6 PSI.

• This reply was modified 4 years, 5 months ago by garry-in-michigan.

[Rick Robbins]

Thanks Gary! Never considered the float even though it makes perfect sense! Maybe someone sells repos or I can coat this one with airplane dope. Can’t say I’ve ever had a float problem before,but this could be the 1st time for me.
Rick

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