1984 GT/300/400 Fuel cap question

[ebinmaine 63,166]

Notice the title is not for a specific model.

 

I picked up a couple new gas caps for our 400 series tractors and the GT 1800.

 

 Stens 125 - 112 made by Kelch.

This should be the exact same cap that Toro purchased and used.

 

 

They don't seem to thread on correctly.

 

The thread is loose and it's very easy to over tighten it to the point that it just snaps by.

 

Are they really supposed to have that little amount of tightening torque? Or do I have the wrong cap? 

[ri702bill 7,339]

Overdid it with the "Bear Claw"?? 

[ebinmaine 63,166]

6 minutes ago, ri702bill said:

Overdid it with the "Bear Claw"?? 

 

Valid question but no.

Even Trina has to be exceedingly careful to  keep it from spinning past.

 

Once it's installed you can grab it from the top with your open hand like you're picking up a baseball and with slight effort just snap it right off the tank.

 

 

I saw an old thread from nearly 10 years ago about this same issue but no solution offered. 

 

 

 

[SylvanLakeWH 24,155]

Three thoughts, not in any particular order...

 

1. New therefore junk?

2. Threads good on the tank neck?

3. Wrong cap 

 

 

[8ntruck 6,376]

I got a Toro replacement cap/gage for my C-195.  Was for a Horse other than the C-195, but I figured gas tanks had a common cap thread.  Nope.  The thread pitch is apparrently different.  The new cap binds up at about 3/4 turn.

 

I'll guess that the threads are different,

[D_Mac 8,226]

I had the same issue. Ordered the cap and it didnt fit.. If i remember right I ordered it for my 416-8 and didnt work but it worked on the C-161. Or vise versa.

[c-series don 7,818]

I have had the same problem, aren’t all the tanks the same since they put them under the seat? Other than the fancy ones with a sending unit, but even those should have the same thread. I just figured it was because it was junk not made here if you know what I mean. 

[Jon Paulsen 282]

8 hours ago, SylvanLakeWH said:

1. New therefore junk?

That's my vote.

 

#1. The Larch.

[76c12091520h 3,296]

Had this exact same problem pop up at the Big Show in 2022 , sold a cap ( with gauge - Kelch brand ) and the customer came back later with the same concern. The old cap threaded on just fine but the new one would not get tight. Upon further examination, we determined that the neck on the tank had been collapsed over the years from the seat hitting it and the threads on the tank and the old cap had conformed to each other. We had a new old stock fuel tank there for comparison and there was between a 1/4" and 1/2" difference in the height of the neck between the 2 tanks. The new caps fit the new tank perfectly.

Edited December 4, 2023 by 76c12091520h

[ebinmaine 63,166]

10 hours ago, SylvanLakeWH said:

Three thoughts, not in any particular order...

 

1. New therefore junk?

2. Threads good on the tank neck?

 

 

2 hours ago, c-series don said:

I have had the same problem, aren’t all the tanks the same since they put them under the seat? Other than the fancy ones with a sending unit, but even those should have the same thread. I just figured it was because it was JUNK NOT MADE HERE if you know what I mean. 

 

It is in fact, verified, a USA made Kelch Brand cap. 

Same as OE Toro.  

 

 

1 hour ago, 76c12091520h said:

Had this exact same problem pop up at the Big Show in 2022 , sold a cap ( with gauge - Kelch brand ) and the customer came back later with the same concern. The old cap threaded on just fine but the new one would not get tight. Upon further examination, we determined that the neck on the tank had been collapsed over the years from the seat hitting it and the threads on the tank and the old cap had conformed to each other. We had a new old stock fuel tank there for comparison and there was between a 1/4" and 1/2" difference in the height of the neck between the 2 tanks. The new caps fit the new tank perfectly.

 

 

 

 

Well folks. 

The verdict. 

 

Thanks for all your comments.  

Combining the above info and thoughts Trina and I set up a measuring station with 3 tanks and 4 caps. 

Caps are the originals from the first two tanks and two replacements that prompted this thread.  One old cap has a gauge. One does not. Plain black plastic.  

 

Tank #1. 1986 417A.  All 4 caps fit and tighten fine.  

Tank #2.  312-8 with a Toro hood. Year unknown. Low hours machine.  All 4 caps fit and tighten fine.  

Tank #3.  1984 Workhorse GT 1800. 

The two OE OLD caps fit fine and screw on tight. 

BOTH new caps will screw on but immediately run past a thread thereby making it impossible to fully tighten.  

 

So we measured the tanks and caps.  

All 3 tanks were within a few thousandths of each other at the outside of the threads. 

Both the 417 and 312 tanks have threads with sharp edges. 

 

The GT 1800 tank has threads with a more rounded appearance.  It also has a ridge at the bottom from an old cap (long gone). 

 

 

The two OLD caps were within a few thousandths of each other at 1.99 and 2.03 ID of threads. 

The two NEW caps both measured 2.08. 

 

We figure that the combination of rounded (worn??) threads and the larger ID of the new caps renders them unusable.  

 

 

[Maz91 108]

Not sure if this would be helpful but that GT1100 I just picked up has a cap if you need one! 👍🏼

[ebinmaine 63,166]

Just now, Maz91 said:

Not sure if this would be helpful but that GT1100 I just picked up has a cap if you need one! 👍🏼

Might want that whole tank!! 

[8ntruck 6,376]

@ebinmaine - good study.  I'll measure my C-195 tank OD and the ID on both the old and new caps when I get a chance.  My good calipers are at our Mo. location, so it will be a while before I get the measurer and measurees together. 

[CCW 1,206]

This discussion on caps makes me glad I rebuilt the top of my cap instead of replacing it.

 

[ebinmaine 63,166]

1 minute ago, CCW said:

This discussion on caps makes me glad I rebuilt the top of my cap instead of replacing it.

 

Agreed.  I saw that.  

Good idea.  

[TractorEd 516]

Here’s the issue I have with the new Kelch caps on a 79 c161 and an 88 310-8 (won’t screw on squarely).

 

 

Maybe a heat gun would help mate the threads?  (Don’t aim the heat gun at the fuel tank!  Not without following the correct protocol.)

Edited December 24, 2023 by TractorEd

[ebinmaine 63,166]

5 hours ago, TractorEd said:

Here’s the issue I have with the new Kelch caps on a 79 c161 and an 88 310-8 (won’t screw on squarely).

 

In the post above where I did a comparison of multiple tanks and caps, we found that the most solid attachment was the old OE caps. 

I didn't note it, I also seem to remember that the one without a gauge was the better of them all.  

 

[TractorEd 516]

Upon further review, the new caps fit fine on the ‘88 310-8, but not the ‘79 c161.

 

i tried the heat gun on the cap threads, but it didn’t fix it.  Almost, but almost made it worse too.

[TractorEd 516]

I grabbed the cap the came with the ‘79 c161 to see how it fits (may not be the original cap, just the one that it had when I got it).  The fitment on it isn’t perfect either.  It does work a little better and tightens up.  Still sits slightly crooked.

Edited December 24, 2023 by TractorEd

[ebinmaine 63,166]

9 minutes ago, TractorEd said:

I grabbed the cap the came with the ‘79 c161 to see how it fits (may not be the original cap, just the one that it had when I got it).  The fitment on it isn’t perfect either.  It does work a little better and tightens up.  Still sits slightly crooked.

 

After our experiment here we figure the threads on the GT1800 we have are worn. 

Likely you've the same issue with your C161.  

[TractorEd 516]

Everybody mail me your gas caps.

 

I will go through them all and choose the best one that fits the c161.

 

Thank you.

[ebinmaine 63,166]

2 minutes ago, TractorEd said:

Everybody mail me your gas caps.

 

I will go through them all and choose the best one that fits the c161.

 

Thank you.

 

 

 

 

 

 

No deal. 

You mail me your C161. Freight prepaid BOTH ways of course.  

I'll use it for a few months and check several gas caps. 

 

I'll even throw in the best old used one I can find.  

[SylvanLakeWH 24,155]

I will send both of you the fuel caps off my E-141's and my A-60 as soon as I locate them... 

[Jon Paulsen 282]

Remember to send a very large SASE. 

 

I suspect only the old folks remember SASE's. 

Edited December 24, 2023 by Jon Paulsen

[8ntruck 6,376]

On 12/9/2023 at 9:55 AM, CCW said:

This discussion on caps makes me glad I rebuilt the top of my cap instead of replacing it.

 

Did you happen to post any details about how you rebuilt your gas cap?

 

My old one is missing the clear cover over the gage.  The new cap threads don't fit well and the float mechanism is too short.

 

I haven't looked closely enough to see if a lens transplant will be possible.