Primer bulb full

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nolivy

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hi,just after bashing the other day, baja has been running great,but noticed a little popping sound when WOT, stopped the baja then I noticed primer bulb is full,no bubbles..... am i running too rich? is it the high or low needle? or both?

Checked the lines, all clear no blockages.

Thanks.
 
nolivy said:
hi,just after bashing the other day, baja has been running great,but noticed a little popping sound when WOT, stopped the baja then I noticed primer bulb is full,no bubbles..... am i running too rich? is it the high or low needle? or both?

Checked the lines, all clear no blockages.

Thanks.
Click to expand...

YES, it's generally an indication of being too full.
If you're sure the fuel lines are not blocked and the return is doing that.

After running for a while, thus the engine's hot (BE CAREFUL - obviously as it's HOT), remove the plug and see what colour it is.

Al.
 
nolivy said:
its rovan engine. i'd say a bit blackish. But running has been very fine since i noticed the bulb full.......
Click to expand...

Black plug = rich
primer bulb full = rich

Sounds to me running a bit rich. Maybe try turning down the H needle 1/16 of a turn. I'll bet you'll find the primer bulb will be down a little.
 
Yeah, check the manual.
Normal Walbro specs are 1 1/4 LOW, 1 3/8 HIGH. All carbs are slightly different.
To get these you CAREFULLY screw clockwise until it cannot FREELY turn anymore. Don't force it as you will damage the needle slightly.
Count whilst unscrewing outwards until you get the settings - if you've had nitro engines, you'll know anyway.
This setting is normally a little rich for standard engines, but I've had to open up a little for my tuned engine, so it varies from carb to carb, engine to engine.
See how it runs with these, then also check out the ENGINE TUNING threads and also PLUG COLOUR threads - these will help you.

It sounds like hassle, but once you've done it, you've a much better understanding, and, unlike nitro engines, generally, once you done it, YOU LEAVE IT - LAUGHING as we say!!

Al.
 
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