Own a older JD 260 mower with a Kawasaki engine, the old 260 runs great, until you park it for a few weeks or months fuel pump loses prime to fix it I pull the line from tank to the pump and suck on it till gas flows. My backwoods hack fixes the problem for another few weeks. In that time frame it always starts and runs like it should. Already replaced the fuel line from pump to carb. No apparent leaks in either pulse or fuel line. Curious what more experienced folks think before I start throwing parts at it?
JD 260 fuel pump loses prime when sitting for a few weeks
- Thread starter jjeff
- Start date
RjCorazza
Elite Member
I didn't reply earlier, because my Kawasaki fuel delivery is likely quite different from yours... On a walk behind, the fuel tank is higher than the engine, but it does have what appears to be a vacuum operated fuel pump strapped to the engine.
I think you're on the right track with the bulb primer for an easy fix, that may only need to be used on occasion. If I were in a similar situation though, replacing the (vacuum?) pump may be the way to go if you don't mind throwing parts at the problem.
I think you're on the right track with the bulb primer for an easy fix, that may only need to be used on occasion. If I were in a similar situation though, replacing the (vacuum?) pump may be the way to go if you don't mind throwing parts at the problem.
oldnslo
Super Member
Pump has a rubber diaphragm that can stretch and soften with age so don’t produce volume they did when new. Some models you can replace the diaphragm others whole pump is replaced.
Another possibility is vacuum pulse line to fuel pump.
third is fuel line from tank to carb. This is under vacuum during operation.
Another possibility is vacuum pulse line to fuel pump.
third is fuel line from tank to carb. This is under vacuum during operation.
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jjeff
Elite Member
Replaced ine from carb to fuel pump with 5/16 tygon when I got this thing the fuel pickup going into tank was plugged pretty bad particularly at shutoff valve on top of fuel tank and it barely ran took that apart cleaned it thoroughly ,disassembled and negated shutoff. When that pump is primed manually by me pulling the main fuel line and sucking fuel through it runs and pumps fuel really good (no I didn't hook up any kind of contraption to test psi nor am I going to). Problem is getting fuel from tank to the pump after sitting for awhile no matter how much I crank the engine. Vent on fuel cap seems to be working and when it's running have ran for hrs with no problems whatsoever, so I'll probably pull rear fender and seat assembly again check the fuel pickup replace rest of fuel lines with tygon install a small primer bulb in that line from tank to pump for when it's parked more than a few weeks to start it. Unfortunately don't have a primer bulb in my possession for that small of line so ill order or look for something. The crankcase pulse line that makes pump diaphragm move looks pretty good but will pull and double check it cuz it's as old as this 30+yr old mower. Will report back later this spring if anyone's interested on final results of my backwoods hackery solution. Main reason for wanting to remedy this problem is I don't care for the taste of gas lol Anyways thanks for the input and was hoping someone else experienced this issue I'm having and how they fixed it?
beenthere
Super Star Member
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Do you have an inline fuel filter that is directional, as some are? An arrow on the filter for direction of fuel flow. ??
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jjeff
Elite Member
Yes in between tank and pump and yes it's still pretty clean, looking changed it last year and oriented in the correct direction unless manufacturers decided to change the arrow meaning Instead of flow direction it now points to the source of fuel in tank, lol no no it doesn't or better not. It's transparent and what is weird yesterday was completely dry granted it was sitting since September, did not find any leaks along the fuel system after I manually primed the line and got it running once again it was running great even at low idle with last years gas. Perhaps I'll change the location of that fuel filter and put it after the pump. I did however put it in the same location as it was when I picked that old mower up though.
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jjeff
Elite Member
Another question for the more knowledgeable folks if the pump was failing wouldn't it effect how that mower runs when it is running? Kind of understand a dried out diaphragm will somewhat rejuvenate itself when exposed to gasoline however.
oldnslo
Super Member
Jjeff
These are my thoughts on a weakening diaphram type fuel pump. When starting vacuum pulses are slower and potentially a little weaker than a running engine so may not prime as well from slower weaker pulse rate but will then produce a flow when engine is running to keep engine running. Again just my thoughts and may not be worth the time it took type this response.
These are my thoughts on a weakening diaphram type fuel pump. When starting vacuum pulses are slower and potentially a little weaker than a running engine so may not prime as well from slower weaker pulse rate but will then produce a flow when engine is running to keep engine running. Again just my thoughts and may not be worth the time it took type this response.
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jjeff
Elite Member
Nope anyone that takes time to type something is worth my time to read it. I'm definitely leaning towards finding and installing a small primer bulb instead of a new fuel pump, especially for a older non museum quality working lawn tractor.