Big Red 250 problem

[riverc 1,316]

It starts and idles good, runs good 1st- 3rd gear when I shift to 4th and open her up it starts bogging down like running out of gas.

[shadetree 5,803]

10 hours ago, riverc said:

It starts and idles good, runs good 1st- 3rd gear when I shift to 4th and open her up it starts bogging down like running out of gas.

start with a carb cleaning ?..or a shindy carb kit..see what that does ?.

[PROV 1,433]

Make sure nothing broke loose in the muffler. If there's junk in there it can partially plug at higher rpms. Same goes for a fuel filter.

[Fishfiles 20,140]

When you do that carb cleaning ^^^ mentioned above Pay close attention to the condition of the diaphragm on top the carb. If it has a tear or hole in it then it will run fine till half throttle then fell like it won’t take the gas 

[riverc 1,316]

Was thinking with the carb being 38 years old maybe I should replace with a new one?

[shadetree 5,803]

5 hours ago, riverc said:

Was thinking with the carb being 38 years old maybe I should replace with a new one?

unless its a china ( junk ! ) ?. you most likely will not be able to buy a brand new oem carb for this atc.

[ATC4ever 1,043]

I'd try & fix the old one, see if theres play/wear on the needle. Def a flow issue under load. Everything posted here is the goods, likely a jet dirty if nothing is worn.

[riverc 1,316]

When I get time will buy a can of carb cleaner remove the carb and see what I can do. Really don't know much about working on carbs.

 

 

[Fishfiles 20,140]

2 hours ago, riverc said:

When I get time will buy a can of carb cleaner remove the carb and see what I can do. Really don't know much about working on carbs.

 

 

Try a cleaning a few times.  

[riverc 1,316]

1 hour ago, Fishfiles said:

Try a cleaning a few times.  

It starts easy idles good my worry is Taking it apart to clean I might mess up the adjustment and won't be able to start it. Got a lot on my plate now deer season coming up wife going in for major surgery to remove a large Adnexal mass on ovaries 11/8 so it will be on back burner till I get motivated to work on it..It runs good until I shift to 4th gear and try wot then like I said it bogs down like running out of gas when i down shift back to 3rd it does ok.

[Fishfiles 20,140]

Only adjustment you need worry about. You screw the mixing screw in while you count the turns.  Usually it is around 2 1/2 turns.  So you put it back where it was to start with. I just looked annd  After market carbs go from $30 - $70 - $100 on eBay.  The worst that is going to happen with a aftermarket carb is it doesn’t run good. It is not going to hurt anything except your wallet if it fails.  

[ATC4ever 1,043]

Could always take a video when you take it apart to help you remember how it goes back together.

[shadetree 5,803]

23 hours ago, riverc said:

When I get time will buy a can of carb cleaner remove the carb and see what I can do. Really don't know much about working on carbs.

 

 

BEFORE you go spraying carb cleaner ( like gumout )..MAKE SURE YOU GET THE AIR/FUEL MIXTURE SCREW OUT, TINY WASHER ( DO NOT LOSE THIS WASHER ! )..AND THERE IS A TINY O-RING, DO NOT SPRAY CARB CLEANER INTO CARB UNTIL THESE PARTS ARE REMOVED !. otherwise you will ruin this tiny o-ring. so..count the turns in, its a slotted jet, watch one end of this slot, count how many turns it takes to seat ( lightly !! ), then remove it. you should have the jet, spring, tiny washer, tiny o-ring when its all removed. most times the tiny o-ring and washer stay down in the carb jet hole, MAKE SURE YOU REMOVE ALL OF THESE PARTS BEFORE SPRAYING CARB CLEANER DOWN IN THIS AREA !.