How to change the fuel pump on a JD LA115

engprosinc

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My daughter's JD LA115 was running erratically. It was difficult to start under full choke, and finally fired after I sprayed WD40 into the air filter section. I changed the air filter and final filter. After running for awhile, it started to run erratically and stalled. I changed the fuel filter and wanted to replace the fuel pump too, but the old pump is held on to the cover with a rubber "thumb tack" for lack of a better description. I tried to pull on the rim or tab on the top of the "tack" but stopped because I didn't want to break the "tack" and it didn't give me any signs that it would come out if I pulled harder.
How do I remove this "tack". Don't want to force it, and the new pump did not come with a bolt or "tack".
Thanks in advance.
 

ILENGINE

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Sounds like the christmas tree style fasteners They can be quite stubborn and may have to pry them out.
 

StarTech

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Not exactly...But they are popped out by prying between the pump and the shroud. If damage they are get replaced.
1631030573729.png
PN 796448 Can be black or cream color.
 

engprosinc

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Thanks. That's what I suspected but I wanted to cover all bases before I tried the twist and pull routine, especially on an old rubber fastener. Couldn't find anything on a Google search, either. That's what concerned me.
It would have been easier if it the pump was mounted with two bolts like my old faithful Craftsman lawn tractor. Oh well. Thanks for the quick response.
Stay well.
 

engprosinc

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Not exactly...But they are popped out by prying between the pump and the shroud. If damage they are get replaced.
View attachment 58243
PN 796448 Can be black or cream color.
Thank you so much.
I might pre lube with a little spray of rubber lube before I try to muscle it out.
I admit I did try prying with a flat head screwdriver between the engine cover or shroud and pump body, but stopped because with my luck, I would break the old pump and the local stores were closed on labor day.
 

bertsmobile1

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Most times they get damaged beyond reuse
I always push them out from the inside
There is a tool for doing this but in reality I never bothered to make one because fuel pumps almost never fail
I have replaced only 1 in 9 years of servicing mowers
pull the fuel line off at the carb end.
hold it as high as you can and crank the engine .
IN good condition an impulse pump will pump a full hose of fuel from a hose around 2' in the air ( my simple 1 minute test )
The 2 minute test is to hook the inlet side to an alternative tank if test 1 fails to see if the problem is the pump or the supply .
 

StarTech

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I agree that these pumps don't normal fail here either. But I have replaced three this year already. Like everything else I get runs of particular failure at times.
 

rustycat

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Why did you spray WD-40 in the air filter? Carb clean or flammable brake clean to get it started. The pump will work even if the mounting clips are not there.
 

engprosinc

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Why did you spray WD-40 in the air filter? Carb clean or flammable brake clean to get it started. The pump will work even if the mounting clips are not there.
I have always used WD40 as a quick engine "starting fluid". Been using it for years on boat, Harley and small engines. Try it
It also lubes linkages, etc.
 

mitchstein443

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I have always used WD40 as a quick engine "starting fluid". Been using it for years on boat, Harley and small engines. Try it
It also lubes linkages, etc.
Um, no you have not. WD40 is not flammable enough for a spark plug to fire it, it will in fact foul the plug and make the enge run like crap. we did this years ago on a prove it argument. CRC WILL fire from a spark plug, but will blow so much smoke the shop becomes unlivable until you get the big fan to blow it out..

IF spraying WD40 into the carb made the engine start, chances are you have water in the carb bowl, the wd40 will displace the water and might allow the plugs to fire if you didn't use too much..

Also it running like crap after sitting for a long time is usually one of two things or both.. Condensation built up in the fuel, drain all fuel put fuel tretment in (and not from the same batch you might have used when storing last time it might be a bad batch)..

Or the fuel in the crab dried up and left it's additives behind to gunk up the crab and jets.. Yu can try seafoam in the gas or other fuel cleaner, or do it right and take the carb apart and thouroughly clean it jets and all...
 
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