Primer Bulb Problem

simonds

Forum Newbie
Joined
Mar 22, 2011
Threads
1
Messages
5
I have a Homelite weed trimmer model ST-155. Started having problems with it staying running and discovered the primer bulb was cracked. I replaced it and the new one won't pump any fuel up from the tank. I replaced the fuel lines and filter last year and they seem to be fine. I can blow into the fuel line and it will come running back out fine. I keep pumping it but no fuel comes up into the bulb. I took the carb apart and cleaned all ports out with cleaner and made sure every part went back together the correct way, but still no fuel. Any advise would be welcomed.
Clayton
 

Sprinkler Buddy

Well-Known Member
Joined
Apr 30, 2011
Threads
31
Messages
289
Sounds like your getting air and it's not self priming, make sure you haven't tightened the screws to much or not enough on your primer bulb.
 

simonds

Forum Newbie
Joined
Mar 22, 2011
Threads
1
Messages
5
Sprinkler, Thank you for the reply. I did tighten the screws down very tight. I will check that tomorrow after work. All points to a leak in the suction tube from the fuel tank, but I just don't think I have one. I blew down the tube and fuel came running back up the tube flowing freely. So this tells me the filter and tube is ok.
 

lakeviewpe

Active Member
Joined
Sep 29, 2011
Threads
0
Messages
69
You need to replace diaphrams and gaskets in the carb. also replace the needle while you are at it, it is all in the rebuild kit. You shoul dbe able to find the kit for $11 or less.
 

simonds

Forum Newbie
Joined
Mar 22, 2011
Threads
1
Messages
5
I think the lines are correct as they are different size diameters and length. I will recheck them after work today. Thanks for the reply. If they are ok I will order a rebuild kit. Winter is coming on and I won't need it, so no big hurry.
 

Sammy the Red

Well-Known Member
Joined
Sep 21, 2011
Threads
12
Messages
299
If it still primed when it was cracked, than you have not correctly installed the new one.

I have replaced a couple of them, tho cracked, they still would prime.....Just a little messy !
 

simonds

Forum Newbie
Joined
Mar 22, 2011
Threads
1
Messages
5
Sammy, It would run for awhile it seemed until it warmed up and then I would have to close the choke half way to keep it going. I thought it may be sucking air into the bulb. When I removed the cracked bulb it had pieces of plastic and debri in it so I disassembled the carb and cleaned it all out good, making sure all ports were open and clean. When I put it all back together with a new bulb it won't draw fuel up from the tank while pressing the bulb. I have had it apart several times to make sure all parts were correctly assembled and they seem to be. I didn't use new gaskets, so maybe that is the problem. I just feel it should at least draw some fuel when pumping it, but none at all comes up. Thanks for the replies, Clayton
 
Top