Murray just won't start (model shows murray 45000X8)

well i got more info on the model/engine

atelast this is all i could read off of the b&s engine and the orange murray sticker shows just 4050008x no B, C, A, nothing. Then below it has part #'s for the blade, fuse, etc. I do not have the manual either, this was given to me from my father in law awhile back.

model: 28R707
TYPE:1120-E1
CODE: 030204ZD


Here has what has been done so far

new fuse, (fuse is good, checked it with multimeter/continuity test), new spark plug, new air filter, changed oil, new gas, also got a new battery, measuring 12.88 volts now, I checked the battery side of the NEW solenoid, that is getting 12.88 volts as well. I have also got a new IGN switch, and that still doesn't work. I still have to jump the solenoid. Wiring seems fine, nothing is loose or broke, I blew out some dirt and just traced wires, but nothing looks destroyed. Still, the only way I can get it to work is to jump the solenoid. I just can't imagine I would have a BAD new solenoid, but nothing surprises me now days. I am sure I can buy a new one to give it a try, or just jump the darn thing each time I cut the grass, it doesn't really matter, but I already put 70 bucks or so in it which beats 1200 for a new one lol. Should I try a new solenoid or are there any other tests I can do at this point?

Thanks

astrolux said:

well i got more info on the model/engine

atelast this is all i could read off of the b&s engine and the orange murray sticker shows just 4050008x no B, C, A, nothing. Then below it has part #'s for the blade, fuse, etc. I do not have the manual either, this was given to me from my father in law awhile back.

model: 28R707
TYPE:1120-E1
CODE: 030204ZD


Here has what has been done so far

new fuse, (fuse is good, checked it with multimeter/continuity test), new spark plug, new air filter, changed oil, new gas, also got a new battery, measuring 12.88 volts now, I checked the battery side of the NEW solenoid, that is getting 12.88 volts as well. I have also got a new IGN switch, and that still doesn't work. I still have to jump the solenoid. Wiring seems fine, nothing is loose or broke, I blew out some dirt and just traced wires, but nothing looks destroyed. Still, the only way I can get it to work is to jump the solenoid. I just can't imagine I would have a BAD new solenoid, but nothing surprises me now days. I am sure I can buy a new one to give it a try, or just jump the darn thing each time I cut the grass, it doesn't really matter, but I already put 70 bucks or so in it which beats 1200 for a new one lol. Should I try a new solenoid or are there any other tests I can do at this point?

Thanks

Click to expand...

Did you WATCH this VIDEO I sent in an earlier post ..?? EXPLAINS a NO-START CHECKLIST !!

https://www.youtube.com/watch?v=A8m88LawN0I&t=10s

Boobala said:

Did you WATCH this VIDEO I sent in an earlier post ..?? EXPLAINS a NO-START CHECKLIST !!

https://www.youtube.com/watch?v=A8m88LawN0I&t=10s

Click to expand...

Yeah I've watched it a few times when I was outside working on it. I even got another solenoid just for the heck of it, does the same thing. I still have to jump the posts to get it to crank. It could be a safety switch or wiring issue, but I've put enough time into at this point. If it starts when I bridge the gap, great. It's 15 years old or so, and was free, so putting in 70 bucks isn't a big deal...I was just trying to get it working "normally", but at this point I am not going to put anymore time or money into it. I can't afford a new one, so when it comes time to cut the lawn, I'll jump it, and call it a day. It cuts off normal (i.e. when I get off the seat/break, and cut it off with the ignition switch) so it seems to still be "safe" when riding, cause I rode it around the yard and when I lifted up, it still cut off like it usually does and when I turn the key off, it does kill the engine, so I guess I'll just use it till it completely dies.

in order for the solenoid to work it need to get a 10 V signal down the trigger wire and because it is electricity there must be a sound ground.
If there are 2 small wires, one is the trigger & the other the trigger ground
Thus one must go better than 10V with the key switch in the start position and the other must show ) ohms to ground.

So you start there .
To test the solenoid you bridge the + trigger wire to the battery cable.
Engine cranks then the solenoid is fine.

If the solenoid only has one small wire then the ground is through the metallic base
You get corrosion there so no ground untill you give it a tap.
So verify the trigger wiring and the grounding.

If no trigger voltage the you have a wiring problem in the cranking circuit.

12 volts goes from the Battery post on the solenoid to a fuse which powers the mower.
Rookie mistake is to put that wire on the starter post thus you can only start the engine by jumping the cable terminals.

Carrying on, the 12V goes through the fuse to the B terminal on the key switch then across to the S terminal ( switch is marked ) .
From there it goes through the PTO & BRAKE safety switches and finally down to the solenoid.
Easiest thing to do is make up some patch cables with a make spade on each end and bypass the switches, one at a time, starting with the key switch B <> S
The switches are simple sliding contact and work flat to flat
I <> I
I <> I

One pair is normally closed ( kill wires ) the other pair are normally open.
If you bridge the kill wires the engine will still crank but not start,
Just don't jump them diagonally.