Classic Winnebagos & Vintage RVs

Topic Boards => Chevy - GMC Chassis => Topic started by: BrandonMc on August 19, 2018, 05:48 PM

Title: What is this P30 Fuel Tank Vapor Component?
Post by: BrandonMc on August 19, 2018, 05:48 PM
Hi,
I'm going completely through the fuel delivery system on my 88 p30 chassis to solve a persistent vapor locking issue. I think its a vent tube assembly? Is it serviceable, and should I be concerned about it?

In the pictures as follows:
There's a fitting in the top fuel tank, connects to vapor hose and then this line that splits three ways, and goes to 3 white fittings which could be an air inlet check valve assembly?
Mounted at the rear of the rv at the bumper as you see here.

perhaps related to this?
Quote from: DaveVA78Chieftain on May 13, 2013, 09:20 AMHere is a reference to a Winnebago recall I found that I believe relates to this: http://www.recallowl.com/Vehicle+Recalls/Automotive/WINNEBAGO/CHIEFTAN/1985 (http://www.recallowl.com/Vehicle+Recalls/Automotive/WINNEBAGO/CHIEFTAN/1985).  It does not give details so you would have to contact Winnebago for information. Dave


Thanks!   
Title: Re: What is this P30 Fuel Tank Vapor Component?
Post by: BrandonMc on August 19, 2018, 06:42 PM
If anyone needs a diagram of a 1988 P30 60 gal fuel tank while it was dropped, this may help.


Also, its that elbow to the vent tube assembly mentioned in the above post.
Title: Re: What is this P30 Fuel Tank Vapor Component?
Post by: circleD on August 19, 2018, 07:16 PM
If I remember correctly my 84 carb system had a vent tube on the tank. It was ran to the rear bumper with a plug that was a one way valve like on differentials. Maybe they changed it due to the fuel injection to keep the pressure consistent in the tank with that fancy stuff. It will pull a vacuum while going down the road if nothing stops it.
Title: Re: What is this P30 Fuel Tank Vapor Component?
Post by: BrandonMc on August 19, 2018, 07:29 PM
Quote from: circleD on August 19, 2018, 07:16 PM
If I remember correctly my 84 carb system had a vent tube on the tank. It was ran to the rear bumper with a plug that was a one way valve like on differentials. Maybe they changed it due to the fuel injection to keep the pressure consistent in the tank with that fancy stuff. It will pull a vacuum while going down the road if nothing stops it.

Opened up the box to the 3 way split, and this is one of three white fittings in there. I can't see to the inside of the fittings to determine if they're simply open to the air, or are a valve of some kind.


I also run a quadrajet carb as well as the in-tank fuel pump.
Title: Re: What is this P30 Fuel Tank Vapor Component?
Post by: Rickf1985 on August 19, 2018, 07:47 PM
It is a tank vent, the valve is to prevent liquid from coming out.
Title: Re: What is this P30 Fuel Tank Vapor Component?
Post by: BrandonMc on August 19, 2018, 07:48 PM
Quote from: Rickf1985 on August 19, 2018, 07:47 PM
It is a tank vent, the valve is to prevent liquid from coming out.


should they be replaced, or are they fine do you think? I'm trying to see about a replacement part, but searches coming up with nothing at the moment.
Title: Re: What is this P30 Fuel Tank Vapor Component?
Post by: Rickf1985 on August 19, 2018, 07:55 PM
It is nothing more than a ball and cage so it is probably good. Not likely you will find one.