Zenith carb problem
Firstly - congratulations on a great site and forum. The go to place for old lawnmowers!
On to my problem - I found a Suffolk colt (according to the plate 75g14 model 21a) in reasonable condition dumped outside a neighbours house.
I took it in and tried to get it going. It goes but only runs without the mixture screw in place.
I've tried cleaning all the jets and the air holes in the carb (blown them all through with wd40) but nothing has worked. The minute I even put my finger over the hole it dies.
Shall I just run it without the mixture screw? Weird?
I'm sure you guys can help!
Forums
Another thing to check is
Another thing to check is item 21 on the parts list that Wristpin posted. You may not know that this comes out and is known to be prone to blockage.
Thank you both.
Thank you both.
I cant remove the small jet 21. I worry about crimping the hole if I squeeze too hard. Any advice on removing without damaging?
Yes, they can be a problem to
Yes, they can be a problem to get out. Try a kettle of boiling water over the carb or even boiling it up on the stove then gripping it end on with pliers and giving it a wiggle ( technical term). The other end is the calibrated bit so the exposed bit can take a bit of abuse. I've even resorted to gripping with side cutters and laying a nail across the top if the float bowl to act as a fulcrum and then levering!
The good news is - they are still available!
Okay thanks will try.
Okay thanks will try.
Just a note to say I finally
Just a note to say I finally managed to free the slow running jet. Gave it a clean and it did the trick. Now it seems the mower will only run with both jets closed. Weirder and weirder!!
Must be getting fuel from
Must be getting fuel from somewhere so may be the fuel level in the float chamber is too high or the gasket between the two sections of the carb is not sealing where it should be.
Welcome to the forum. As you
Welcome to the forum. As you say , weird!
Mixture screw - there are two , the vertical one on top of the carb is the slow running adjustment and the horizontal one at an angle to the float bowl , the main jet adjuster. I'm assuming that you are referring to the latter? Still weird!
Two thoughts. Despite your endeavours with the WD there may still be a blockage some where and carrying on from there have a good look at the tip of the main jet adjusting screw. I have seen the tips broken off and jammed in to the carb as a result of heavy handed attempts to adjust. Logically, if the broken tip is still in there removing the screw should not make any difference but worth a look.
The attached pics of the carb showing the passages that the fuel takes for both the main and idle systems may throw some light on the problem or suggest an area for cleaning that you may have over looked.
https://www.dropbox.com/s/7fq3j5ddzcxqo5l/Zenith%20carb0001.pdf?dl=0
https://www.dropbox.com/s/smgavyf7tw1a3si/Zenith%20carburettor0001.pdf?…
Please report back.