Stealth126 54 #1 Posted May 5, 2018 Also, anyone have trouble with the new plastic fuel pumps? I was getting a little fuel in the crankcase, so I replaced the fuel pump. I'm sure it was coming through the carb, but I thought it couldn't hurt. Turns out it could hurt. After getting it set up I readjusted the carb and I have cut the grass twice. Tonight as my son and I are mowing, it starts to sputter a bit. Then after another pass it died. The first thing I checked is fuel flow and sure enough just a trickle. The arm barely touches the cam. It is so touchy that if you tighten the bolts with the pump slid up as far as it will go it won't pump enough fuel. You actually have to slide the pump down as far as it can with the slop around the bolts in order for the cam to barely touch the arm enough to pump fuel. Did I get a junk pump or is this the way it works? Share this post Link to post Share on other sites
ACman 7,525 #2 Posted May 5, 2018 (edited) A lot of guys use a cheap electric fuel pump off that famous auction site. Here’s one @953 nut has used. I’m sure others will chime in. https://www.ebay.com/itm/HEP-02A-New-Gas-Diesel-fuel-pump-Inline-Low-Pressure-electric-fuel-pump-12V/191558570132?hash=item2c99c7d094:g:ZC0AAOSwEyRag2o3 Edited May 5, 2018 by ACman Share this post Link to post Share on other sites
squonk 38,967 #3 Posted May 5, 2018 I have used the plastic pumps with success but prefer electric. Are you sure the cam lobe isn't worn down? I had to replace a pump on my C-160. I had an extra metal pump and installed it and still nothing. It would pump if I pushed the arm with my hand but not with it installed. That's when I went electric. 1 Share this post Link to post Share on other sites
MalMac 1,328 #4 Posted May 5, 2018 (edited) If it ran good I would assume you have it position right and you have the correct pump with the right length and shape of arm. Sometimes new pumps fail right away. I have had new ones junk right out of the box. It would most definitely not be heard of one failing right away. Edited May 5, 2018 by MalMac Share this post Link to post Share on other sites
Stealth126 54 #5 Posted May 5, 2018 It pumps by hand, but it barely touches the cam. If I could bend the arm 1/8 inch it would work great. Would put my metal one back on, but the gasket ripped. I put my finger on the cam at different positions and it feels smooth. No groove. Gotta love replacement parts. Share this post Link to post Share on other sites
Stealth126 54 #6 Posted May 5, 2018 My metal one leaks fuel just a bit around the exposed side of the diaphragm. Just dampens the front of the block over time. Very little. Thought this would be an improvement but now it doesn't look like it. Share this post Link to post Share on other sites
MalMac 1,328 #7 Posted May 5, 2018 One of the reasons they went to the plastics housing ( besides manufacturing cost) was the metal pumps were known for warping then causing leaks. They used those metal ones for years. Did you check the arm configuration vs the old and if it is the same, check the travel of the arm on the new one vs the old. Maybe the new one is not traveling (up and down) as far thus not creating enough pumping action. Share this post Link to post Share on other sites
Stealth126 54 #8 Posted May 5, 2018 It looks the same as the old, and it travels well. It is not being pushed far enough up to pump. There is 1/8 to 3/16 travel before the diaphragm is engaged. If that wasn't the case it would work fine. Our if the cam pushed it a little further. Just barely touches the cam. Arm needs to be bent a touch. I am wondering if anybody else experiences this with plastic. If not I'll return it and get another one that hopefully works. Share this post Link to post Share on other sites
MalMac 1,328 #9 Posted May 5, 2018 Starting to sound like you may have a faulty pump. Not unusual at all. A lot of the aftermarket pumps come out of the same place as OEM ones do now. A lot of people have switched to electric pumps. Myself I still go the mechanical. I can see where the electric pumps would be more trouble free though. 1 Share this post Link to post Share on other sites
Stealth126 54 #10 Posted May 9, 2018 The supplier agreed to replace the pump. It's in the mail on it's way to me. Now I'll know if it's the plastic pumps or if this was a one time occurrence. It's been running good since the last time I messed with it. 1 Share this post Link to post Share on other sites