Lawn mower question

[nisryus]

So I have inherit my neighbor's remington rm110, which he doesnt't used since he had lawn service to do the works.

It is almsot brand new as he had only used it once. I have replaced the gas, and checked the oil. However, it doesn't starts. It is one of those model which you have to prime it, engage the choke, then pull the cord to start.

First step, I checked the spark plug, and it is good and clean. Tested by taking it out and start the mower with its side touching the metal chasis, the current was visible.

Next I checked the carburetor by removing it and took it apart. Checked the float pin and vavle. All clean and no build up. There was gas in the chamber so the gas filter in the tank is good.

Checked the gasket and looks good. So seal was no issue.

I did noticed that the spark plug was dry, this means gas was not getting where it should be. What might be causing this?

 

[mindless1]

I'd double check by using a can of starter fluid, spray in the carb to see if that allows the engine to fire a few times. If you have no starter fluid you can try using a spray bottle of gas but it is less effective.

If gas isn't being pulled in, you have a carb clog or a vac leak somewhere, or possibly a diaphragm that's torn or inflexible due to age. When you prime it do you feel or hear gas being pumped in? Eventually the primer bulb itself will get a crack in it, though if it is pumping gas, the mower should have fired a few times trying to start it.

When I don't see anything obvious, I do a carb cleaning and rebuild with a gasket kit. If it were really old (lot of hours on it), I might've suggested doing a cylinder compression check but that seems unlikely in this case.

Another thing I try when I get tired of pulling the cord is to use a drill and socket to spin the engine, let it spin for a good while, making sure to spin the right direction and having the brake lever held down (or wrap something around it to hold it down). I have a rather beefy drill that can do that, but an impact driver or impact wrench might be the more common tool to use today.

 

[nisryus]

Thx mind.

The mower is farily new ( less than a year) and neighbor only used for less than 4 hours. I did checked the diaphragm and it looked good with no visible torn or any issue.

No crack with the primer bulb as well. However, i didn't hear gas being pump it when priming. Check the tubing and looked good.

I took the carb apart and cleaned it as well. Fuel filter is not clogged and fuel was going through and in the chamber at the bottom.

It just baffled me why fuel is not going through. Last thing i can try is as you have suggested, use a drill and spin the engine. Wife might not like the idea lol.

 

[Torn Mind]

Water in the gas is a common failure mode; the old Briggs was engineered against that--not perfectly immune though, as too much water can still cause failure--but now everyone uses the "gas above the carb" design. Clean out the tank and drain the lines, then let them dry; rubbing alcohol could speed up the process a bit. (I know since I'm landed myself many free mowers that were tossed out due to failure. Even one I took while working pizza delivery and came back after finishing my shift.)

Carb or brake cleaner work fine in place of starter fluid and said chemicals are more versatile.

Carb is probably shot if complete gas drain is done and the spray-in-engine-then-pull shows the engine turns. The remedy is either to clean the carb or replace it. While carb cleaner seems to be the obvious choice to clean, a long term soak might require alternative solvents, of which I'm not sure which are most effective yet not damaging to whatever rubber might be in there, such as diesel fuel.

 

[mindless1]

Last thing i can try is as you have suggested, use a drill and spin the engine. Wife might not like the idea lol.

Spinning it with a drill won't cause any harm (since it's not a 2 stroke so it doesn't depend on the fuel for lubrication), but to clarify I mean to take the top cover off to do it on the flywheel nut, not on the bottom, blade nut.

That's not the last thing I'd try, rather I'd go ahead and do that before taking it back apart again. Sometimes, fuel sat and gummed the carb but a little still gets through, so by spinning the engine enough, you can pull a little fuel through and declog it enough to run. Fresh fuel helps, depending on how old the fuel in it is.

The next/last thing, is get a carb rebuild kit, clean it, rebuild it, and if the kit doesn't come with a primer bulb, I might go ahead and get one of those while I was at it, if convenient to do so. Some designs allow taking the bulb off and examining it closely, but any time you start taking pieces off, you risk that they may not seal well and you may then need a new one. Personally, I wouldn't have even taken the carb off if I didn't have new gaskets to put it back on with. Often they can be reused, but sometimes not.

 

[nisryus]

Thx guys.

I took the fuel tank, fule filter, and the carb apart again. Clean everything and made sure there is nothing gumming the carb, blicking the fuel filter. Going to put them back again this weekend, lettin gmy kid do it since I have been showin ghim how to (he is a big boy and needs to learn).

Will check the compression as well, just to be safe. Like what Mind said, i am afraid I am making the seal loose, but everything looked just fine. The carb looks fabulous. I only saw a little sediments in the fuel bowl. Gasket and the diaphragm looked sparking new. The damn thing is almost brand new, I guess I just didn't want to give in so easily (and to prove to the wife if I fixed the other old mower we had a few years back, I can fix this one too)!

 

[Mandres]

A lot of times the internal passages on the carb get plugged up and they hard to clean without an ultrasonic tank or a small gauge wire.
My suggestion would be to check on ebay for a replacement carb. You might be able to grab one for $20 and get back up and running.

 

[StoicGuy]

I second Mandres, I had a mower sit for a winter after I forgot to run all the gas dry in it and it varnished and stopped the carb dead in it's tracks.
I think I took that carb apart twice before I finally got every bit of it, varnish is nasty.

 

[Steltek]

Don't give up on it. I guarantee you that the one time the prior owner used it, he probably used gasoline containing ethanol in it and then let it sit until giving it to you. That is pretty much guaranteed death for any carburetor, and sometimes even a carb rebuild kit won't salvage them. It has been my experience that this is the case, no matter how clean that the carburetor otherwise looks to the eye.

I'll bet that if you stick a new carburetor on it that it runs just fine.

 

[Greenman]

Don't give up on it. I guarantee you that the one time the prior owner used it, he probably used gasoline containing ethanol in it and then let it sit until giving it to you. That is pretty much guaranteed death for any carburetor, and sometimes even a carb rebuild kit won't salvage them. It has been my experience that this is the case, no matter how clean that the carburetor otherwise looks to the eye.

I'll bet that if you stick a new carburetor on it that it runs just fine.

And given that carbs are $15 from amazon, there really isn't any reason to take it apart.

 

[Scarpozzi]

I know this sounds stupid, but is there a valve in the line? Some mowers these days put a valve between the tank and carb. I've actually seen mowers that I assume people returned when they wouldn't start due to the valve being closed.

Otherwise, the gas cap could be causing issues by creating a vacuum. Some are meant to pressurize, but some can cause the gas not to flow.

 

[Gardener]

Are you depressing the blade control lever? Looks like one of those styles that kills the spark if you don't engage it.

Other than that, you have fuel to the bowl, but a dry spark plug, sounds like carburetor issue. However you should be able to get it to fire with starting fluid, or a squirt of gas directly into the throttle body.