Log in

View Full Version : Problems with 16.5hp B&S Motor


dunedindawg
Jul 15, 2006, 07:50 AM
I have a 16.5 HP B&S motor, OHV. I have replaced the ignition switch, the battery, the solenoid and the fuel soleninoid.

The motor ran when shooting starting fluid in it and dies right down. I pulled the main carb jet out and cleaned it, it appeared gummed up. The mower had been running fine when the season ended last year.

The mower will now mostly just back fire.

It appears to be getting plenty of fuel and has great spark and compression. This leads me to believe the mower may be out of time.

I did take the coil off, as I was thinking it may need a new one. I re-installed it exactly as it was, at least I think. I was reading that the height of the coil could throw off the timing. Does anyone know about this? I pulled the valve cover off and all rocker arms are snug and seem to be working fine.

The spark plus is now getting fouled with gas which leads me to believe that the motor is firing at the wrong time. Please help, I don't know what else to do with it.

thebriggsdude
Jul 17, 2006, 12:51 AM
The mag bolts up to one spot, one spot only... doesn't have to deal with timing... the internals either if it was never gone into. The flywheel key would...

I'd give the carb another good cleaning... why? Lots of times once isn't enough to clean it out good.

dunedindawg
Jul 17, 2006, 05:33 AM
So what do you make of the fuel solenoid getting no power? It does not click at all. I tried testing both the old and the new fuel solenoid by running a hot wire to the positive battery terminal and then a ground to the battery as well. The only thing that happened, the wires I was using got extremely hot.

thebriggsdude
Jul 17, 2006, 06:11 PM
You had it hooked to the battery right, correct? Then that is very weird to say the least...
http://www.tulsaenginewarehouse.com/drawings/allwiring.pdf
Here's some help on the wiring for briggs engines.

dunedindawg
Jul 17, 2006, 06:31 PM
I did have it hooked up right, as far as I know. There are only to male lead prongs sticking out of the fuel solenoid and I put the hot where the grey wire would connect. Thanks for the wiring diagram. I'll look it over some.

dunedindawg
Jul 21, 2006, 04:55 PM
Believe it or not I got the tractor running. I took the diagram of the wiring from the link tbd gave me and decided to go have a look.

It got me thinking, do I have a 5 or 6 prong ignition switch? I went and looked and then started to see what wires ran where and it wasn't adding up. Where they plugged into the ignition switch is not where they were going on the diagram. It then dawned on me, one of the 1st things I changed after the battery, was the ignition switch! I got it from NAPA, they said they sold allot of parts and this ignition switch would be fine.

I took the old one out of the bag, thank goodness I kept it. I hooked it up and the motor turned over like a champ!! I took it out and ran it yesterday and it took me a 3rd of the time to cut the lawn. Thanks for all you help.

One other question I have. Is there a way to set the deck a bit higher? I had it all the way on the high position, but would like it just a bit higher. I'm going to put more air in the tires to see if that helps, but I'm not sure about the psi for them reither. I have no manual, but will be getting one from Briggs soon.

thebriggsdude
Jul 21, 2006, 08:49 PM
Glad to be of help, that should be a point, the ignition switches are not all alike...

I'm not sure of the brand of mower you have, but make sure you don't go over too much on the max psi rating of the tires... maybe 5 extra and that's it.

dunedindawg
Jul 22, 2006, 06:06 AM
I have a Yard Machine, it's about 3-4 years old.

thebriggsdude
Jul 23, 2006, 12:44 AM
Mmmm, mtd... can't really help you there with the deck (don't know how the newer ones are set up,don't work on them, nor really like em) You can try the tires.