'98YZ - Check your accelerator pump!

When I did my Main Jet install last week I found corrortion the the shaft of my accelerator pump and the shaft was frozen. I shot it with some WD40 and worked it lose and it's working for now. I'm going to pull it apart and fix it right this week. You may want to check yours! Anybody else seen this? If so reply so we can get an idea if this is a common problem. I'd read that it was somewhere before.....


Dirt and dust can get past the shaft and into the top of the diaphram. Periodic cleaning is necessary, more so in muddy conditions. Just remove the bowl and diaphram, clean and reassemble.


Scott F

'00 YZ426F

'99 YZ400F sold

'98 YZ400F sold

i put a spot of grease up in the boot to prevent $hit from going down in to the pump. I guess this s why they changed the carb huh?

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