Dumb question of the day - fuel feed pump

[chsdiyer]

How important is the fuel feed pump? I finally figured out that's what the clicking noise is associated with when i turn the key on, and for a while now, mine has been intermittently working. Like it will either have a delayed start or it will only click a few at a time off and on, but the tractor will still start. after reading some other posts it seems this pump is just there to prime the injectors, but if you have a full tank of fuel, the weight/gravity will do the same anyway. I guess if not starting with about a half tank full or more you'd need this to be working, but otherwise not critical?

Would this part be under warranty?

 

[crashz]

I'm not sure on an LS, but generally you want plenty of fuel flow going into the injection pump. I would guess that they designed it that way to protect the injection pump from starvation and even if the engine runs, the injection pump may not be happy.

 

[mrmikey]

......mine has been intermittently working.

Possibly has come up to pressure and cycled off?

 

[chsdiyer]

Thanks for the feedback!
Crashz - I can't tell if this little feed pump shuts off or not once the engine gets running.
mrmikey - Sorry, what i meant in intermittently working is sometimes i turn the key and it works just fine. some times i turn the key and it start almost right after the glow plugs light goes off. more than not at this point, i turn the key and it'll click a few times, then go off, then click a few times then go off and keep doing little bursts of working and some times will eventually stay on, but usually it just keeps the on and off pattern where it's on maybe 2-3 clicks and some times a few seconds worth, but kind of sporadic. I'm not 100% clear what the function of this part is but ever since i got the tractor new, it's always been turned on with the key on setting and never turned off until i switched the key off or started the engine. Seems like at this point the part is on it's way out.

 

[Supraman0614]

What is the actual problem? Does the tractor start when you turn the key? Does it stall during use?

 

[chsdiyer]

The tractor will start. I'm just trying to determine:
1.) is this part failing, cause i'm on my last year of warranty and wondering if i should try and get it replaced before i'm out of pocket
2.) what does it actually do. is it only starting now because the tank is full and the gravity pushing the fuel is sufficient, but if the tank was lower filled would it not be starting. Based on the way i hear the clicking, i'd say the part is failing, but hasn't really seemed to impact anything yet.

 

[Supraman0614]

I'm not sure it would be covered under the warranty. LS has been somewhat stingy with regard to what is covered. It should continue working while the engine is running (although you won't necessarily hear it). If it were failing, you would likely have trouble getting the engine to start or keep it running, especially under load, regardless of the fuel level in the tank. If you had to replace it, there are many different in-line 12V pumps that would work fine; you don't necessarily need the LS part. You would just have to be sure that it is rated for enough pressure and flow. If you had access to a service manual, it might list the operating pressure of the feed pump.

A cheap way to try to diagnose might be to siphon most of the fuel out of the tank and run the tractor around for a while to see if it stalls or you have trouble starting it.

 

[workinonit]

My guess is that once pressure builds up it cuts off and cycles to maintain pressure

 

[chsdiyer]

Thanks for the input!! So what is the clicking sound you hear actually doing. that's the only indicator i have that it's not working as it should be but not sure what that sound is. There was another post a while back that someone posted a video they did capturing the sound...http://www.youtube.com/watch?v=oOHUcIm0IZg I'll see if i can get mine on video showing what I have going on.

 

[Supraman0614]

That's the pump doing its pumping thing.