Contour Enthusiasts Group Archives Forums General Common Interests Battery Question (riding mower)

Ok, this is not about my car, but a riding mower. LOL. Anyway, we are trying to figure out if the battery is bad or if it's the battery cables. We have to jump start the mower every time we use it. Now my grandfather says it might be the homemade battery cables, but I think it's the battery, cause it does it every single time. Even if I am mowing, the lawnmower will give out, and I have to push back over to one of our vehicles and jump it again. It starts immediately though.
Also, I am not sure if it's the battery that's causing the mower to die out, or if we are still having carb problems too. Earlier I was able to keep the mower running by lowering the throttle and pulling the choke out. Then once I keep it running, I push the choke back in, turn the throttle up and it's fine for a bit, until about 10 minutes later and I have to do the same thing again.
I just don't want my hub & our friend to have to tear the mower apart if it's not the carb. Any ideas?

Thanks.

edit: Subject revised

Sounds like maybe a clogged fuel line or a sticking float valve in the carb. Try pulling the carb, blowing out the fuel lines and cleaning/replacing the float valve. (or diaphram valve depending on model...) Get the engine model # off of the block tag plate label thing and you can get the right parts from a lawn mower or small engine rapair shop. Also pull the plug and check that the gap is around .035. (I just returned my mower to the land of the living and mowing )

hhmmm, you are in Tenn........ get yer a$$ over here to SC and help. LOLOLOL.
Thanks. Will have hub do all that too. We did have something stuck in the gas tank, in the little hole leading to the fuel line, but hub has pulled the actual lines off, blew in them, looked in them, and they were clear, but it still does this.
I thought they had replaced a diaphram before, but I am not sure. I know he bought one. Can't tell you which one it is though. He's planning on pulling the carb out and rebuilding it this week I think. Hopefully. LOL.

We have a buddy that is an aircraft mechanic right now, but he used to have a pt job working on mowers before he came into the Air Force. We are trying to get him to help, but he now has a part time job at Auto Zone, so we don't know if he'll have the time to help us.
It's just getting annoying having the thing crap out on me constantly while trying to mow. Usually it craps out about 10 times before I get the lawn finised, but today only once. I was very surprised. I was actually able to do the front yard, it crapped out, finished the front, went to the back and mowed it twice. I had to mow it once at the highest deck placement.......yes the back yard was THAT bad, then again at the middle setting. I might go back out tomorrow morning at do it again at the lowest setting. We have the winds & rain from Huricane Fabian heading our way. I want to get my grass as low as possible before all that hits and makes the grass grow really fast.
Thanks again. I will have him check that stuff out. What do you think about the battery though? Think we should still change the cables or get a new battery?

Put the battery on a trickle charger over night. Once done charging, check the voltage of the battery all by itself with nothing hooked up to it. Let it sit for 10 minutes then check it again. If it holds voltage, its good.

While the battery is not hooked up, check the resistance between the + cable and the - cable. It should be INFINITE. If not, the cables are faulty or not quite hooked up right.

My little push mower stalled on me a couple weeks ago. The air filter was major dirty. I cleaned it for use that day, but I have since replaced it with new. Check your filter.

Hhhmm, we don't have a charger. That bites. The air filter is cleaned, we cleaned it not long ago, and hub checks it everytime he has to fight the mower. LOL. We'll see what our friend wants to do since he works at Auto Zone pt now, maybe he can test it for us or something.
Thanks

what do you neeed a good battery for? I agree the carb is screwed up, but just push the thing. It's not like chasing after your car, riding mowers are generally slow.

Not this one. It's an 18hp Briggs & Stratton. Very good mower, just 13 years old. My hub is going to take the carb apart and rebuild it this week. We have no other mower, and I wouldn't worry much about that except that we live on a military base and we MUST have our lawn mowed every week. If we don't, we get written up. If we get more than 20 points in a 2 yr period, we get kicked out of housing. It's pretty easy to get those 20 points too. We got 16 our first 2 months here because we didn't have a mower.
We can't afford to get a push mower right now either, or else I wouldn't be too worried about it. Well, my hub has one week to get the thing done, or at least put back together and running by next Tuesday at least. Folks here are very iffy about letting others borrow their lawn care tools.

Persistant charging problems in a riding mower usually mean that the generator brushes are gone (most mowers use a generator, not an alternator). Check with a mower shop, many types have replaceable brushes.

if teh battery is more than 5 years old then I'd suspect the battery. If the battery is newer than it's likely that the cables are the problem.

If the cables are dirty of have some crusty build up on them, take the cables off the battery, clean the battery terminals and clean the wire terminals. If there is any white or yellow/greenish crust on the connections they are definately dirty and need to be thoroughly cleaned. In severe cases the cables may need to be repalced.

As for your engine dying problem it is fuel related. I don't want to say that it is a problem with the fuel metering in the carb becasue once you choke it its good for a little while. If it was a fuel metering problem it would always be there as long as the choke is off. I'll go with poor fuel flow to the carb.

You're on the right track. Re-building the carburator and making sure to clean all the parts before you put it back together will make sure that the carb is working correctly. But, I also suggest changing the fuel filter at the same time. If the fuel filter and the carb rebuild don't fix the stalling problem then its probably the fuel pump.


The higher horsepower Briggs engines like your 18hp one, have diaphram fuel pumps that work by the air pulses generated inside the crankcase as the pistons move back and forth. The pump is probably mounted to the engine, near the top and is probably square in shape and has 2 fuel lines going to it and one hose that goes to the crankcase.

These pumps are notorious for going bad on engines older than 10 years old because the modern fuels have additives that weren't present back in the day and they tend to harden the diaphrams which loweres the ammount of fuel they can pump. Replacement diaphrams are made of a material that will resist hardening. Usually the pumps are pretty cheap and for a few more dollars than the rebuild kit you can get a new one.

Take the battery to an auto parts store. They can be tested with the little handheld testers just like a car battery.