8n carb question

crusty8n

New User
Hello Im new to the forum. I've been a proud owner of an early 8n for a year now. I have a question for you folks that has been pestering me!! The tractor ran fine until I thought it was a good idea to turn off the fuel because the drain plug was slowly leaking. When I opened the fuel shutoff to start the tractor, a bunch of debris flowed through the sediment bowl and plugged the carb. I rebuilt the carb and installed a Napa clear inline fuel filter. My tractor has the fuel hose not the copper tubing. Got the fresh carb in and the tractor ran like a sowing machine!! However... after some time of running, the clear filter would fill with air. the tractor would never falter, but when I would turn off and try to restart, no go. Also I noticed a slow fuel seep in the center gasket and around one screw. thinking if fuel was weeping out, perhaps air was being drawn in creating a vapor lock. So... I pulled it apart and put some gasket sealant approved for gas on it. Well, it's sealed up good now. However the problem with the clear filter running dry still exists. Any advice would be greatly appreciated at this point!! Should I drain and clean the tank? (don't want to) Should I not be running the inline fuel filter? Should I take it back to the copper fuel line? Any advice will be greatly appreciated. thanks for the help!!
 
Welcome to the forum!

It is a great idea to turn the fuel off.
Every time you're done using it.
Lack of use of the valve may have let dirt gather there?
Also, two full turns on for normal operation. Opening it all
the way opens a lower opening closer to where dirt deposits.

The filter may or may not be an issue, depending on what it is.
The rubber line that close above the engine/manifold scares
the begeebies out of me, so I put the correct line on them.
That "correct line" is not copper, it is steel.
Standard 30 inch long 1/4 inch brake line fits fine and has the
correct fittings on each end. Just bend it to fit. $4 or so.

There are three screens in that line, one in the elbow that goes
into the carb, one in the top of the sediment bowl above the glass
and one inside the tank on top of the sediment bowl assembly.
I would make sure they are all there and clean.

If your gas tank is full of crud, I would bite the bullet and clean
it. It will cause trouble at the worst possible times until it is.

Let us know what you find.
 
crusty........glad you like yer 8N, ALWAYS turn OFF yer under the tank GLASS fuel filter. 2-turns fer ON. When starting, ittza 2-rumpa-rumpas BEFORE a QUICK pull on yer spring loaded choke knobby. Remember yer starter motor switch and ignition switch are NOT interconnected. Lotta newbie tractor drivers fergitt to turn ON the IGNITION switch. (BTDT, grin)

I have NO PROBLEM with GAS rated rubber hoze. (ittza printed on the rubber) As fer auxiliary filter, remember filters have a "direction" to be mounted in yer GRAVITY fed fuel system. Many times yer filter DRAINS clear of fuel thru the carbie float scheme. Donna worry, itt'll fill just as soon as yer tractor engine starts suckin air thru the carbie.

Sometimes, when it don't fill'em-up, ittz 'cuz mud-dobbers done closed-up the vent hole in the DOME at the front of the tank where you can't see it or gitt-too-itt. Just un-screw yer gastank capple and relive the VACUUM. They sell a VENTED gascap that solves the clogged dome vent problem.

You know it is eazy to keep the top-half of yer 10-gal gas tank full so the bottom half don't rust. Unfortunately, modern no-lead gas is fulla additives that can CLOG yer brass jets. Then you haffta do a carb boil-out and clean-up with caustic carb dip. I use pressurized BRAKE cleaner to blow thru things.

TIP: gitta acetylene gas welder tip cleaner to make certain yer brass jets are clean. Don't try to remove the MAIN jet at the bottom of the carb bowl. It take special long NARROW blade screwdriver. (it seldom clogs)

BTW, you can NOT vapor lock a gravity fed system. .......HTH, Dell
 

We pretty much all had or have same issue as you. My screen filters kept plugging up constantly and my reserve never worked.
So I removed the sediment bowl assy from the bottom of the gas tank and disassembled and cleaned it up and added new cork gaskets. (keep a few gaskets around).
While I was at it I flushed out the gas tank some and a load of crud came out including bits of grass, hay and plenty of rust.

The 3 existing filter screens provide enough filtering that an in line filter really isn't needed.

Have not had a problem since.
 
" I've been a proud owner of an early 8n for a year now."

Got the manuals yet? Check out tip # 39.

Re your questions.......see tips 9, 15 & 21.

If you don't have a tubing bender, you can buy the OEM steel fuel line.
75 Tips
 
The in line fuel filters made for a car or truck will cause many more problems then they ever fix. The 3 factory filters with just fine and have for decades throw away that plastic filter and go with metal line before you have a fire and then have no tractor
 
Thanks for the input I'm going to pull and
clean the tank. Get a steel fuel line.
Pull the sediment bowl inspect.
 
" Thanks for the input I'm going to pull and clean the tank"

Google any of the popular tank cleaners.....like Eastwood's POR15. It costs $87. Read the directions. It's not easy.

Then check the price of a new tank: about $140, plus shipping.
75 Tips
 

As Dell said, seeing no gas in the filter doesn't mean the bowl isn't full.

Mistake I made putting a see-thru on mine was this.
Those mini sized filters have 2 sizes to accommodate two sizes of line -- the in and out pipes are stepped down. I was told by the store that it is for 5/16" OR a 1/4" line but it seems to be for a 1/4" and 3/16" line.

So that explained why whoever had put the previous one on my tractor, had razor-knifed the small stepped down sections off of the filter end pipes.

I haven't razor-knifed the small ends off mine yet and it does labor for fuel every now and then and like yours, the filter is often almost empty.

After i clean the tank and buy a carb screen, I'll probably eliminate the filter. If I keep the filter I will reinstall it in a vertical position on this NAA.
 

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