18 Mag Starting Issues

[juniors1282]

Nate, I'm sure I replaced the fuel lines on it when I put the 18 mag in it. I don't think I washed the tank out but I did look in it and don't remember anything in it. Doesn't mean there's not though. It seem's like it's not holding fuel pressure. So it needs primed if it sit's for a long time. Like an old car if you run it out of gas, most time's you have to prime it to get it running. I think if you find something in the tank you should just replace the lines again while your at it. Good luck!!

[Matt G.]

It's starting to sound like you need to put a fuel pressure gauge on the output of the pump and crank the tractor to tell you if it is or isn't the fuel pump that is bad. If the pump is good, the gauge will jump to about ~2.5psi and stay there; if it is bad, the needle on the gauge will just flop around as you crank the engine.

[maddog784]

Matt,

I cleaned the carb again this afternoon and after reassembling it, it didn't seem like it was getting any fuel. A buddy of mine is picking me up a pressure/vacuum gauge at Harbor Freight(cheap tools, but they work) and we're going to look at that tonight - just got off the phone with him. If we do find a fuel pump problem, what do they go for? Is it possible (or even worth it) to rebuild one?

Thanks for all the advice everyone - just trying to get it to start the first time, every time.

[juniors1282]

I have one I'll send you if you need one. Let me know.

[Oak]

Bypass it for now. It's not needed.

[maddog784]

For now, the mower is doing the exact same thing. Here's what I did to try to remedy the problem:

1. Soak the carb overnight. Cleaned out and reassembled.

2. Replace all the fuel lines. I'm sure Eric replaced them when he did up the engine, I just wanted to rule out any possibilities. Cost me all of $4 and I moved the new fuel filter. Put the fuel filter after the fuel pump; I was thinking that dirt may be working itself out of the pump and clogging up needles/jets.

After this, it started just fine. Time always tells the story though, as the next morning it was back to the same old thing. Really getting fed up with it. I have an older Carter 26, but the choke and throttle adjustments aren't lined up the same way.

Any words of advice?

[CHWNY]

Hey Maddog, It sounds like you might have a slight vacuum leak. The carb has a float bowl yes? Is there a solenoid on the carb? Providing the needle/seat is good it should be full of fuel after shutting down (you do bring the engine to idle speed for a few seconds before shutdown Right) and have a ready supply of fuel for restart. I didn’t read if there was more dirt the second time you removed the bowl, there could also be some water in the fuel this would be at the bottom of the bowl and want to be sucked up first on starting and would cause the same symptoms. The filter should be a paper element one not the brass type the latter will let some water to pass through. There are several ways to check for vacuum leaks, carb cleaner, propane, water … all have some drawbacks use all with CAUTION!!!!!!!! CHWNY

[Matt G.]

Did you check the fuel pump like I've suggested? You've pretty much eliminated everything else.

When you get it running, I would put the filter before the pump so any crap that gets sucked in doesn't tear up the fuel pump.

[maddog784]

There was a little dirt in the bowl, but nothing that seemed to be a problem. After soaking, there was a lot of dirt in the bottom of the bucket, but I think that was from the outside. Fuel pump works fine. Water in the fuel makes the most sense in that once it starts running, it will cycle between running and stopped with no problem; however, once it sits overnight, the water settles to the bottom and becomes the 'fuel,' thus causing it to not fire. Also explains how a little bit of gas in the carb will start it right up. Also explains why it sputters a little bit at the beginning, but after that, won't fire.

[maddog784]

I forgot, solenoid on the carb? Like a primer pump? No - there is no such thing on this model.