Replacing Fuel Pumps in Itasca

[Invisable]

I am going to replace both fuel pumps in my 91 Itasca Sunflyer due to age. I intend to cut a permanent access door to get to the electric fuel pump in the rear 90 gallon tank. I bought an endoscope to locate the piping/sending unit access to the tank, but I discovered I hate endoscopes.

Does anyone have a picture of a 90 gallon tank from a Chevy P30 chassis? The cut I have to make in right in front of the bathroom door if all my measurements are correct. I just want to be sure I am right.

By the way, if you have a 90 gallon tank, take care of it. I can't find one anywhere for sale. It was a Winnebago add-on.

Love you guys. My refurbish project went very well. I will post some pictures after I clean up the interior.

Jim

[leesdx1]

Hey Jim, Sorry can't help you on the pictured, but there is a tread, "Generator fuel line," that has a picture of a Ford fuel tank. I'm on the same boat as you regarding the interior location access hole for the fuel tank. Right by the bathroom door going into the bedroom. You seem like you're not to worry about cutting the hole in the bathroom floor. How would you make the hatch? Let me know how it turns out, as I want to do the same. Pictures would be great. Thanks

[Invisable]

Thanks. It is actually a 100-gal tank with a downcomer vent set at a depth to create a 20-gal expansion chamber. I was planning to cut a couple of inches off the vent tube to increase the usable volume to 90-gals. The vent tube is the secondary tube on the filler spigot.

I will use the piece I cut out of the floor as the door, with steel flat screwed around the periphery to support the door on it edges from the bottom. To make this work, the cut in the carpet must be larger than the cut into the floor ( a rotary blade going through carpet is messy). One screw on each side of the door through the flat should hold it securely in place. Glue (or staple) the carpet back down and the repair is complete if you used a razor to cut the carpet in the first place. A throw rug over the area and the deed is done, although if done properly, it should not be noticeable.

I will take pictures as I go along. Anyone should be able to duplicate my work.

Jim

[Sunny1]

Did you consider draining and dropping the tank instead of cutting a hole in your floor? I ask because I eventually will need to do the same thing, and am not sure which route to go.

[Invisable]

Hi, Sunny. Getting under the 20K pound RV with minimal clearance is a real hassle for me (70 yr old disabled vet). I want a quick and simple way to access everything. Cut carpet, cut hole in floor (skill saw), remove piece, and you are looking at an all-weather, very quick way to access your fuel pump, which might come in handy when it is 10 below outside and you know no one for 500 miles. A spare GM brand pump for my RV is $17 off eBay - just ordered two of them. Cost of pump at NAPA (same brand) is $91. Dealer cost to replace - $1800.

I did the same thing for my Z71 - cut a 4" hole in the bed and made a flapper. Why? My pump went out 20 miles from home. Towing was $165, dealer cost to replace $17 pump (same GM pump) was $880 and a handshake. Next time I will replace it on the side of the highway at the cost of the spare I will carry in my tool box faster than the tow truck can reach me.

Jim

[Sunny1]

Jim,
That all makes good sense. Post plenty of pics of the project, and any lessons learned.

$1800 for the dealer ... Ouch!!! That's one of those projects that when you do it yourself, and if all goes as planned (which seldom seems to be my case) that you'll feel really good about having done it, and saved a big chunk of cash in the process.

Kirk

[leesdx1]

Originally Posted by Invisable

Thanks. It is actually a 100-gal tank with a downcomer vent set at a depth to create a 20-gal expansion chamber. I was planning to cut a couple of inches off the vent tube to increase the usable volume to 90-gals. The vent tube is the secondary tube on the filler spigot.

I will use the piece I cut out of the floor as the door, with steel flat screwed around the periphery to support the door on it edges from the bottom. To make this work, the cut in the carpet must be larger than the cut into the floor ( a rotary blade going through carpet is messy). One screw on each side of the door through the flat should hold it securely in place. Glue (or staple) the carpet back down and the repair is complete if you used a razor to cut the carpet in the first place. A throw rug over the area and the deed is done, although if done properly, it should not be noticeable.

I will take pictures as I go along. Anyone should be able to duplicate my work.

Jim

Jim, since your cut out will be in the carpet area, should be easy to make unnoticeable. My area is vinyl and will be a task to make it unnoticeable. But, as you said, put a throw rug over the area.

As people suggested working via the bottom of the coach, I have to agree, with the price of labor and stranded nowhere you pay the price to drop the tank. I too, rather have the access inside the coach. Thanks

[bobbelcher]

Okay so I just got done replacing the fuel pump in my 1998 pacearrow and I think I can be of some help here...

I looked and took measurements and found the fuel pump was just about 3 to 4 inches into the bathroom from the bedroom. So after examining what it would take to drop the 75 gallon tank (which meant removing leveler jack supports and wrestling a 75 gallon tank that was 3/8's full of gas) I decided to just go for it and started cutting after carefully taking educated guesses where it was at. I had plans to make the cutout a permanent hatch access for the fuel pump.

I took my first cut thru and realized the floor was only about 5/16 deep as i cut thru the laminate and the first layer of plywood. then there was about an inch and a inch to inch and a quarter deep "void". I was using an oscillating saw which really was the bees knees for this job... BUT my surprise when i got the rectangle cutout i had to basically cut that top piece of plywood into sections and chisel it out. the floor is a piece of 1/4" plywood with a 1 to 1.25" styrofoam insulation glued and sandwiched between a top 1/4" plywood and a bottom 1/4" plywood. and right smack dab in the middle of my cut was a steel tube... I DIDN'T COUNT ON THIS but there is a steel tube running right down the middle of the coach and then right at the edge of my cut that was deepest into the bathroom was another steel tube running to the driverside of the coach. I am guessing this is support for the shower as it only went to that side of the coach. this makes replacing this with an access very difficult but I said i would keep going and figure that out once I got the motorhome up and running again.,

Once I got a hole cut i was faced with a plastic membrane. My friend who was helping me with this project said ohhh thats cool. they got a plastic membrane to keep water from getting to the bottom side of the coach. So without thinking i cut a small hole in it. and realized there was another void below that membrane. I cut a larger hole in it and realized i had about an 8 to 10 inch "void". i reached my hand down and thats when i realized what I had just done.... I just made the dumbest mistake. I cut a hole right in the top of my fresh water holding tank

I was so upset with myself for not thinking about this but my friend said its okay we can patch it. with some stainless steel plates and silicone. so we remove the fresh water tank and inspect the damage and it looks like his idea of the stainless plates and silicone should work nicely. but now what we were faced with was ANOTHER FLOOR. This is when we felt really stupid as we could have saved ourselves a lot of trouble and just cut the basement floor and NOT had to cut a hole into my bathroom floor.

So we said we are already this deep into it lets get it done. The bottom floor came out MUCH NICER. It was a similar set up as the upper floor without the steel tubes in the way with the addition of a thin galvanized sheet metal skin on the very bottom. (had they had a steel tube running down the middle of this, we would have just done all this work for nothing as the fuel tank was directly below this floor. We did manage to jackpot the location and ended up having to cut a 14 X 14 hole in the floor as the fuel pump is massive. Once we got the hole cut we removed the fuel pump and went to the parts store. We had attempted to find the pump ahead of time but unfortunately no one could tell us with certainty what pump we had. so we got the sending unit out and had to pass it thru the basement storage to get it out. Advance auto was able to find the correct pump now that we had this apart but had to order it.

This morning We pulled the sending unit apart, replaced the pump and started reassemblying things. we got the pump in and the motorhome fired right up. it was a breath of fresh air. Now I have 3 holes to fill/fix.

My attempt to fix the bottom hole so far has come up empty. I was going to use flex seal to seal the cut edges to prevent water leaking in and all that. But flex seal eats the styrofoam insulation. So I am still working on how I am going to fix this hole. The upper hole I am going to take a piece of plywood in from the basement storage and screw it to the bottom of the floor.and then fill the void with insulation and top it off with a piece of 1/4" plywood and glue the vinyl flooring down to that 1/4" plywood and then caulk the seams with a white caulk. I think this will keep it very unnoticeable. I am also considering putting new vinyl flooring down in the entire bathroom as it wouldn't take much at all to do. I like keeping this hole accessible for the future though as it was nice to get to the top of the fuel pump, BUT it could have been done all thru the basement storage (although it would have been tight as that void is only like 12" tall or something.

Save yourself a lot of work and go in thru the basement storage if possible.

I am sorry this is so long and I hope that I helped you or someone out there.

[leesdx1]

bobblecher, thank you, thank you for the tip and it did help me save my floor. My Bounder's fuel pump is in the same location as your. After reading you reply I went out to look at what you said and sure enough their was the water tank sitting right above the tank.

My question is, you cut a hole in the basement to access the fuel pump. But if your water tank which sits in the basement was right above the fuel pump, then the hole you cut to access the fuel pump was off center, right? Sorry I just cannot picture it.

[bobbelcher]

I measured the fuel pump from the driverside. The pump was 40 to 50 inches off the outside wall of the driver side. (sorry I cant remember the exact measurement off hand.)

My water tank extends over the center in kind of an L shape. but the long leg of the L is horizontal. the tank is like literally a horizontal L where the long leg of the L is horizontal and skinny (like 8 to 10 inches deep and wide like 30 inches wide and extends 3/4 of the width of the rv. then the short side of the L is bigger and takes up an entire basement storage area. so when I cut the hole into the water tank i didn't even give it a thought that it extended over the center of the coach.

I guess I should explain the compartment that my water tank is in a pass thru basement compartment and is 75% water tank and the other portion on the drivers side is storage or the area for the water pump and gravity fill and all the water lines.

Hope this helps.

[bobbelcher]

[Invisable]

Time to climb back under the Itasca and make sure there are no such obstacles. My initial examination showed nothing above the fuel tank, but I am going to check again.

I am still waiting for delivery of the fuel pumps anyway, so time is no issue. I don't want to create more problems than I already have.

Thanks for the posts, guys. It has been very informative. One can never have enough information when one departs from convention.

Jim

[Invisable]

Crap. My heater vent lines run right over the fuel tank. I would have to cut through them to get to the fuel tank. You guys just saved me a lot of misery even if I now have to drop the tank. My tank has no drain on it and the gas gauge is showing half full. This is going to be something a lot less than fun.

Thanks, guys.

Jim

[kustom]

buy a inline elec. fuel pump and use it to drain your tank