1989 Honda trx300 Carb rebuild

[clemsonfor]

I have torn the carb out of the Honda 4wheeler i just bought. It was coughing and spitting back and needed a rebuild. It was pretty gunked up.

Anyway does anyone have any anvice or the process i need to go through, especially the choke adjustment, i took it out but not quite sure of the process to put it back in? The choke seemed like the only way to get it out of the carb was to unscrew it by turning the carb around the cable?

Or does anyone have a manual that they can scan the Carb rebuild pages? Just curious before i go looking to buy one on ebay?

 

[Winmac]

The nut/sleeve on the enrichiment valve(choke) cable should spin, for the adjustment you want the plunger to bottem out with a bit of slack in the cable in the off postion.

 

[cropdusting]

That carburetor is pretty simple. Get yourself a service manual for that thing if you want pictures to look at, but the choke (not actually a choke it is an enrichment circuit with a plunger) just unscrews and there is really no adjustment needed. Now they can get worn causing fuel leakage through the passages causing a slightly rich condition under normal operating temps (enrichment closed or off) but that is rare.

You might want to check out my site. I have various how to videos for motorcycle and ATVs. Here is one where I disassemble a carburetor very similar to the one on your trx300

Basic carburetor disassembly and diagnosis - The Junk man

I also know your trx300 has a constant velocity carburetor so inspect the rubber diaphragm that controls the slide and jet needle for tears or holes. At over 20 years old the rubber will start deteriorating.

 

[clemsonfor]

Will that rubber top boot thing be in the Kit i ordered?

It looks pretty simple but way more complicated than any of my boats carbs. And other than those and chainsaws and lawnmowers i dont really do other carbs.

 

[BrianDT]

Soak it for a day or two in seafoam or carb cleaner. There are many small places in there that link to gunk up.

Also, dont try to clean the jets, just replace them. They are a buck or two.

Is this a 300x or a work machine?

 

[clemsonfor]

Soak it for a day or two in seafoam or carb cleaner. There are many small places in there that link to gunk up.

Also, dont try to clean the jets, just replace them. They are a buck or two.

Is this a 300x or a work machine?

its a 300 fourtrax, not a work machine for a job if thats what you mean?

The jets supposedly are in the kit? They both look clean. its soaking in carb cleaner as we speak.

 

[Tollster]

For future reference on the carb cleaner...save your money unless you intend to shoot it down the throat for deposits while the carb in on the machine and it running.

Otherwise....go look in mama's cabinet for some pine sol, then do the soaker...Mr. Mikuni will thank you....
Be sure to check the before and after picures Here:

The Pine Sol Degreaser Thread - ADVrider

 

[clemsonfor]

For future reference on the carb cleaner...save your money unless you intend to shoot it down the throat for deposits while the carb in on the machine and it running.

Otherwise....go look in mama's cabinet for some pine sol, then do the soaker...Mr. Mikuni will thank you....
Be sure to check the before and after picures Here:

The Pine Sol Degreaser Thread - ADVrider

??? I know the spray can only gets the crud outta the throat, thats why i put the carb body into a "SaftyKleen" barrel of carb cleaner at work.

 

[Tollster]

??? I know the spray can only gets the crud outta the throat, thats why i put the carb body into a "SaftyKleen" barrel of carb cleaner at work.

sounds like you have it all under control..

 

[cropdusting]

Yeah sounds like you have it under control, however you did completely disassemble the carburetor taking out all the rubber parts correct? If not most good carburetor dips will damage or dissolve the rubber parts. You have a CV type carb and it has a big diaphragm in the top of the carb that needs to be removed. And don't be intimidated it functions pretty much the same as any other carburetor.