Reinstalling my 522xi and GT18 fuel tanks

[Blue Chips 183]

On the 5xi-series tractors, the plastic fuel tank (which I assume is some kind of polyethylene) is secured at its top and sides by several irregularly-shaped pieces of foam rubber sandwiched between the tank and the rear fender.

 

The old foam rubber on my GT18 had deteriorated to what was essentially powder, which allowed the tank to flop around, and it's probably not in any better shape on my 522xi, which is the same vintage (2001).

 

I haven't yet been able to find any OEM or specific aftermarket replacements for the foam pieces, but if anyone knows of any, let me know. In the meantime, I'm going to experiment a bit and try fabricating some replacements.

 

I didn't know how thick the original foam was, since there wasn't any intact foam to measure, so I thought I would start by determining what the space is between the fender and the tank. To measure the space, I stuck little mounds of modeling clay at several locations on the tank, placed a little piece of polyethylene over each one to keep it from sticking to the fender, laid the fender in place with the mounting holes aligned with the captive nuts in the frame, and pushed straight down on the fender until it contacted the frame. When I lifted off the fender, the height of each mound of clay was mashed down to match the space. All of the mounds measured 9/16" or very close to it.

 

 

 

The foam rubber will need to be a little thicker than the space, so that it compresses just enough against the tank to hold it securely. I'm going to have to guess as to what thickness and compressibility would work best, based on a combination of intuition, logic, and black magic. It's possible that I might have to try a few different foam rubber combinations before I find one that will hold the tank securely without stressing anything.

 

To begin my first experiment, I just ordered some 3/4" foam made of a blend of Buna-N, neoprene, and vinyl. It's listed as having good oil resistance, and it's considered ultra soft (rated at 4 psi to compress it 25%). This is a closed-cell foam, but the original foam might have been open cell (I think there are some pros and cons to each). I will need to be careful to place the foam pieces so that they allow drainage and not trap water anywhere. The foam should arrive in a day or two, and I'll post an update on how it goes.

Edited 19 hours ago by Blue Chips

[gwest_ca-(File Mod) 11,710]

Seeing under the rear fender pan reminded me of this service bulletin. Most likely does not apply to you.

May get an idea for the shape of some of the foam. The rear one not in view.

https://www.partstree.com/models/73545-520-lxi-toro-garden-tractor-sn-089000001-089999999-1998/fender-and-fuel-system-assembly-11/

 

Hope you have the service manual

 

Service manual split up for higher resolution

 

[Blue Chips 183]

6 hours ago, gwest_ca said:

Seeing under the rear fender pan reminded me of this service bulletin. Most likely does not apply to you.

 

My 522xi has cruise control, but the serial number is not in the list of affected units. I checked just now anyway, and the wiring is routed correctly.

As to the tank venting, it's been fine, and both of my tractors have a different (newer?) vent tube configuration than the one shown in the service bulletin.

 

6 hours ago, gwest_ca said:

May get an idea for the shape of some of the foam. The rear one not in view.

https://www.partstree.com/models/73545-520-lxi-toro-garden-tractor-sn-089000001-089999999-1998/fender-and-fuel-system-assembly-11/

Hope you have the service manual

 

Even though the foam pads on mine had deteriorated, you could still see the remnants of the adhesive backing before I cleaned it off, so I know where the pads went and how they were shaped. I just don't have an actual sample of the pads in good enough condition to see what kind of foam was used and how compressible it was, so I'm going to wing it and see what works best. Who knows, maybe I can improve upon what was used originally.

 

And yes, thank you, I have files and/or links for all of the manuals for my 522xi and GT18, as well as the Kohler engines.

 

Edited yesterday at 01:28 AM by Blue Chips

[Pullstart 68,057]

Reading the thread topic, I thought you were acquiring more fuel tanks, or securing them for future use!    Great thread!

[Blue Chips 183]

2 hours ago, Pullstart said:

Reading the thread topic, I thought you were acquiring more fuel tanks, or securing them for future use!    Great thread!

 

I can see where the topic title could have been interpreted that way. 

 

I just addressed the situation by carrying out a disambiguation operation upon the inexplicit verbiage to avoid potential misinterpretation (i.e., I edited the title). 

 

 

Edited 20 hours ago by Blue Chips

[kpinnc 15,534]

3 hours ago, Blue Chips said:

just addressed the situation by carrying out a disambiguation operation upon the inexplicit verbiage to avoid potential misinterpretation

 

I suddenly felt like I was working.

 

...oh wait a minute, I AM at work! Hate it when that happens...