1991 GXT800 all kinds of problems

[GKLinMT]

Hey all,

Thanks for all the great posts! I've been reading for a couple of days in preparation for my new project.

I bought a 1991 GXT800 Workhorse for $100 yesterday.

Pros:
It's mostly all there and what is there is ugly but straight.
Already been lifted somehow and has extra shock mounts with coil-overs in the rear (the welding doesn't look bad surprisingly)
It's got the 2 cylinder 4 Stroke 295 CC motor that turns freely and it does spin when you press the pedal
Brakes, including hill, appear to work


Cons:
It's missing half of the airbox
Missing the nosecone
The R/N/F switch is in rough shape and doesn't appear to actually pull a cable in one direction
The wiring is a disaster
Tires are shot
Gas in it was really nasty

[LukeL]

That’s the front body off of a 70s- early 80s model. They don’t accept a front nose. Strange it’s a four stroke though.


Sent from my iPhone using Tapatalk

[Gearhead1956]

I don't know what you have there!

But being a gas 4 stroke you did go wrong!

Good luck, let us see what you do with it.

[Skoal82]

I fixed up one of them for my dad. The nose cone has been changed out I believe, mine had the four stroke style front cone. Also made of diamond plate like the back.
I also have some air boxes for it, if you pay for shipping I send it.
Good luck on your build.

[drift240se]

My knowledge of this is limited but isnt that the front cowl from a 3-wheel cart. Would the original front not be diamond plate?

[GKLinMT]

Thanks for the replies all, I've already made some progress but now I'm stuck.

Skoal82, thank you for the offer! We'll exchange addresses via direct message, you rock!

I had to pull all of the wiring to the engine, it had been messed with so many times that nothing was right. I rewired it per the schematic and I have hot spark with new plugs.

I also pulled the carb, tore it down a bit and soaked it overnight, it was disgusting. Sprayed out all the jets with carb cleaner and reassembled it. I can almost get it started but it won't quite catch and is backfiring through the carb really badly.

There's also something wrong with the carb linkage as it will not return to idle, it seems like there's nothing pushing back and I'm not sure which spring should be responsible for that, the carb linkage is really mixed in with different levers and stuff.


I also found the problem with the FNR switch, one of the cables had come loose from the plate at the rear end, I'll put a wrench on it properly later and that will be fixed.

Lastly, the PO had added an electric fuel pump and all of the fuel line was huge. I bought the right fittings and converted it all back down to 1/4" with a fresh filter and fresh premium gas + a bit of seafoam.

What causes the carb backfire usually? Valve adjustment?

[GKLinMT]

Originally Posted by Skoal82

I fixed up one of them for my dad. The nose cone has been changed out I believe, mine had the four stroke style front cone. Also made of diamond plate like the back.
I also have some air boxes for it, if you pay for shipping I send it.
Good luck on your build.

Skoal82, I can't find a direct message feature anywhere. You can email me at glenik (at) gmail (dot) com

[ptmtp26]

Your back firing may have something to do with the lack of a air box. Sometimes if the vacuum is wrong (too much air flow) they just won't run right.


Sent from my iPhone using Tapatalk

[GKLinMT]

Thanks,

After comparing my carb to the pics of new ones online I've realized that some knucklehead has lost a couple of the screws from it. Who knows what else is wrong with the carb. I ordered a new one, it will arrive Tuesday

[GKLinMT]

On to the front nose of this beast:

I see what everybody is saying and it does look like the front end of the really old Marathons. However, there are mount plates underneath and properly spaced holes all the way around the front end. It sure looks like there is a piece missing to me.

If you look at the picture of Skoal82's Workshorse, it has a plastic or rubber cap around the front. I think mine is missing that piece.

No idea where I might be able to get one though. I can't imagine my local junkyards have any of these things lying around.