Replacement Honda Carburettor

[RBZ5416]

I have a 2003 Honda Izy with I think the GCV135 engine. Despite all the love for the Izy, mine seems to have been a Friday Afternoon Special & has tormented me for most of the last 20 years. It's currently in its usual failure to start state & I'm about to attempt to strip the carb & clean it. I was just wondering if, given how regular an event this is, it would make sense to have a spare carb to swap? I could then at least strip the other at my leisure.

So the question for the guys that work on them is are any of the clone carbs worth buying, or is it the usual case of getting what you pay for?

And in typing it's just occurred to me that the last one that was fitted might not be genuine. Is there a reliable way to ascertain a genuine Honda item?

 

[Burnerman]

Sorry I missed this one!
The Izy carb is simple but reliable and easy to work on......a supply of compressed air is great but an aerosol of carb cleaner is essential.
If it doesn't like cold starting, the first thing to check is that the choke flap on the carb front is actually moving fully to close the carb venturi - a very common fault that is cured by adjusting the cable in it's clamp.
Try a new plug too - NGK BPR6ES is the one.
Post back if you need any help with the dismantling.
A genuine Honda carb and a Chinese replacement are hard to tell apart - only some marks on the casting give it away!
John

 

[RBZ5416]

Thanks John.

I'd actually found the original carb & had a practice stripping that. But my local Screwfix was out of carb cleaner so had to order some. In the meantime a local guy who'd been recommended got back to me & said he could collect in the afternoon, so it's gone off with him. Biggest problem I have with trying to work on it is I have no bench, so trying to work at ground level in a dark shed or in between showers just adds to my woes.

The original carb was a Keihin with what looks to be a brass body, & the one on there now has silver body, so probably a knock-off I've been ripped off for in the past! He took the original carb away as well but did comment that although a previous (alleged) attempt at sonic cleaning had failed to revive it, that the limiter on the pilot was still in place. So that jet may not have been cleaned.

But while I have your attention, what are your thought on running the carb dry between uses? Some seem to swear by it & others only at the end of the season.

 

[Burnerman]

You will notice that the carb has two 10mm bolts on the bottom of the float chamber.
The central one is to remove the float chamber, the one just to the side on an angle is a drain.
At the end of the season, remove this one and flush out any residue - and water - that will have collected there.
That's all you really need to do, but if you wish to run the engine afterwards feel free!
The slightest bit of water inn the float bowl does cause rusting which you need to avoid.
For info, the pilot jet is below a brass phillips screw under the throttle mechanism, but to adjust the pilot mixture that screw alongside with the lead cap has to be undone - as it is you can only adjust it 1/4 turn. Best to leave it be if the engine ticks over well.
Some carbs have the pilot jet formed into a plastic boss below the slow speed running screw - that one just levers out.
Hope that's of interest!
John