Replace grommet and cap around fuel tank

13/02/2025

＜Fuel tank cover＞

When I removed the fuel tank cover previously, I noticed the following two things.

The drain hose grommet leading to the petrol filling port is not the right size
The cap on the cap nut that holds the fuel tank cover is cracked.

For 2, if it cracks over time, other motos may be in the same condition.

Both do not affect driving, but I am concerned about them, so I will replace them.
Note that this time, I prepared an inexpensive after-market part instead of a genuine part.

From this article you will know as follow.

Aftermarket grommets that fit the groove in the gas tank and drain hose
Aftermarket caps for cap nuts

Date	9th April 2022
Subjects	Maintenance, Failure, Repair
Shop or DIY	DIY
Difficulty
Working hours	0.5
Costs [Yen]	287

1. Goods to use

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No.	Products name	Manufacturer	Products number	Quantity	Amounts[Yen]	Purchase this time
1	Pliers for moto	STRAIGHT	12-0003	1	1,750
ST5	Grommets	GEO. PRINCE TAKESHITA	PG-4 NG-79-H	10	166	○
ST9	Bolt cap M6 hard	YAHATA NEJI	–	2	121	○
					2,037	287

2. Replace grommet and cap around fuel tank (STEP 1-11)

STEP

Remove fuel tank cover

First, remove the fuel tank cover.

(For details, please refer to the maintenance record ‘How to remove fuel tank cover’)

Left side of fuel tank

The first step is the grommet that holds the drain hose in place.

＜Left side of fuel tank＞

The size of the grommet does not match the hole diameter (φ14) and thickness (4mm) of the fuel tank. (hose outer diameter: φ10)
So, when the grommet is attached to the hole in the fuel tank, the hose is crushed.

I don’t think the hose will be blocked, but I didn’t want the grommet to stick out.
So, I left it out of the groove.

STEP

Remove drain hose

Now, let’s get to work.

＜Remove drain hose＞

Slide the clip that holds the drain hose down.
Disconnect the drain hose from the fuel tank by hose pliers.

STEP

Remove a clip and grommet

＜Remove a clip and grommet＞

Once the drain hose is disconnected, remove the clip and grommet from the hose.

STEP

Comparison of old and new grommets

＜Comparison of old and new grommets＞

Left: Old Genuine part / 90480-16801 2.2g
Right: New Geo Prince Takeshita 1.1g

The size is totally different.
I don’t know if the grommets are not set up correctly or if the tank hole/thickness dimensions are not given.

Now, I can put the new grommet on in the reverse order.

STEP

Comparison before and after grommet replacement

＜Comparison before and after grommet replacement＞

Before:
The grommets were loose.
Well, I think this is not a problem in use.

After:
The width of the grommet groove is a little narrower, but I think it fits better.

STEP

Install fuel tank cover

Next, replace the cover for the cap nut that holds the fuel tank cover in place.
First, install the fuel tank cover.

(For more information, please refer to the maintenance record ‘How to install fuel tank cover’.)

Broken cap

＜Broken cap＞

The cap has a crack in it.

Even with the crack, the cap does not seem to fall off easily.
But I found a good one on the market and will replace it.

STEP

Comparison of old and new caps

＜Comparison of old and new caps＞

Left: Old Genuine parts / 5D7-F3469-00 0.5g
Right: New YAHATA NEJI / Bolt cap M6 hard 0.6g

By the way, the price of genuine parts / 5D7-F3469-00 was 737 yen as of April 2021.
This price for a cap is a little bit expensive…

STEP

Install cap

＜Install cap＞

Place the cap over the cap nut.

The size is perfect.
Of course, it is not as sturdy as the genuine part.
But if it goes bad, I can just replace it again.

STEP

Comparison before and after cap replacement

＜Before＞

It is black.
Cracks are not noticeable.

Hard to get the picture in focus…

＜After＞

As the tank cover is silver, I think it would go with white.

You might be more concerned about the color difference than the texture.
A white tank might be best.
(Would you be concerned about the color of the washer?)