Dometic 300 Repair

[1984fireball]

I need to replace my Ball and gasket. And maybe the water valve/flush pedal.
I see new toilets selling for $120. Should I just get a new one?
And I can't seem to get a part number for the ball. Any ideas there?

[SeaDog]

Welcome to the forum its a great place to get your questions answered. I replaced my original 300 with the 320 elongated bowl and feel if replacing it is the only way to go one of those little luxuries when camping.

[1984fireball]

Did the 320 line up with the existing floor hardware?
And Thank you!

[SeaDog]

Yes it did I did have to rework the water line (very easy)

[rk06382]

Originally Posted by 1984fireball

Did the 320 line up with the existing floor hardware?
And Thank you!

Originally Posted by SeaDog

Yes it did I did have to rework the water line (very easy)

My wife & I love our Dometic 320.
Floor flange is the same but it is longer. If you have an inch behind the Dometic 300, it should fit.

See Dometic 300-320 installation manual to be sure.

Dometic 300-320 installation_manual_55249.pdf

[Ida Ratherbe Camping]

Did the same 300 to a 320.

[modaholic]

When I remove the floor flange from the 300 toilet and put down the new floor flange for the 320 toilet can I turn it in a slightly different position ?

[Ida Ratherbe Camping]

The flange coming out of floor is glued solid. Just replace bolts that come with new toilet, install new foam gasket, and set new toilet. Easy 15~20 min job

[modaholic]

What is all involved when replacing the floor flange ?

[kenandterry]

Upgrading from a 300 to a 320 will be difficult if not impossible IF there’s not enough room from the center of the floor flange to the back wall.

From their website, it shows the dimensions of all the different model toilets.

Round versus elongated toilet is an improvement, but do you have the room to install the longer (front to back) of the toilet bowl?

Just sayin’

[rockfordroo]

Originally Posted by rk06382

My wife & I love our Dometic 320.
Floor flange is the same but it is longer. If you have an inch behind the Dometic 300, it should fit.

See Dometic 300-320 installation manual to be sure.

Attachment 179399

Unless I'm reading it wrong, Fig 3 in your attachment shows the distance from the flange centerline to rear of the unit is 8.5" for the 300 and 11" for the 320. That's 2.5" by my math.

[pppitiful]

Originally Posted by kenandterry

Upgrading from a 300 to a 320 will be difficult if not impossible IF there’s not enough room from the center of the floor flange to the back wall.

From their website, it shows the dimensions of all the different model toilets.

Round versus elongated toilet is an improvement, but do you have the room to install the longer (front to back) of the toilet bowl?

Just sayin’

When I changed our Dometic 300 to a 320 in the 2304KS the 320 was too long to fit in the existing space - it would hit the wall behind the toilet and not be aligned with the flange. The wall that was the issue was a piece of paneling separating the bathroom to an outside storage compartment. I removed the piece of paneling and shimmed/framed out the wall to give me the needed room for the Dometic 320.

Now I need to find a person that would like a slightly used Dometic 300 (for free).

[modaholic]

Originally Posted by rk06382

My wife & I love our Dometic 320.
Floor flange is the same but it is longer. If you have an inch behind the Dometic 300, it should fit.

See Dometic 300-320 installation manual to be sure.

Attachment 179399

I have 1 1/2 inches to the wall . Do you it will work ?

[rockfordroo]

Originally Posted by modaholic

I have 1 1/2 inches to the wall . Do you it will work ?

Not if I'm correct in Post #11.

[modaholic]

Originally Posted by rk06382

My wife & I love our Dometic 320.
Floor flange is the same but it is longer. If you have an inch behind the Dometic 300, it should fit.

See Dometic 300-320 installation manual to be sure.

Attachment 179399

I have 1 1/2 inches from the wall , but the install manual says the 320 needs 2 1/2 inches more than the 300. Do you think it will fit, I really want to upgrade to the 320

[modaholic]

Originally Posted by rockfordroo

Unless I'm reading it wrong, Fig 3 in your attachment shows the distance from the flange centerline to rear of the unit is 8.5" for the 300 and 11" for the 320. That's 2.5" by my math.

My math is the same as yours. But reading the post by rk06382 , he states that if you have one inch from the wall the 320 should fit. He’s done it . I really want to upgrade . Maybe I could modify the wall if needed.

[rockfordroo]

If you go for it, be sure to come back and report!

[rk06382]

Originally Posted by modaholic

My math is the same as yours. But reading the post by rk06382 , he states that if you have one inch from the wall the 320 should fit. He’s done it . I really want to upgrade . Maybe I could modify the wall if needed.

Before with Dom 300

After with Dom 320 (measuring for a new Elongated Slow-Close Seat)

The rough-in dimension are on the floor at the center of the flange not at the top of toilet. The flange & gasket allowed for a fudge factor. As you can see in the two photos the 300 is rotated a little clockwise from the 320. The 300 wiggled when I sat on it. The 320 feels solid AND my wife loves it. It was worth the chance that it would fix.

I am going to see if I can install a slow-close seat today. I leave the seat down with lid up for my wife and forget to put the lid down before we start driving. It makes a load crash when you go around the corner.

[modaholic]

Originally Posted by rk06382

Before with Dom 300
Attachment 179531
After with Dom 320 (measuring for a new Elongated Slow-Close Seat)
Attachment 179532
The rough-in dimension are on the floor at the center of the flange not at the top of toilet. The flange & gasket allowed for a fudge factor. As you can see in the two photos the 300 is rotated a little clockwise from the 320. The 300 wiggled when I sat on it. The 320 feels solid AND my wife loves it. It was worth the chance that it would fix.

I am going to see if I can install a slow-close seat today. I leave the seat down with lid up for my wife and forget to put the lid down before we start driving. It makes a load crash when you go around the corner.

Can you tell me what the measurement is from the back of the 320 to the hold down bolts ?

[rk06382]

Originally Posted by modaholic

Can you tell me what the measurement is from the back of the 320 to the hold down bolts ?

I will measure it this afternoon.