Model ID for diagram

06compound

Member
Joined
May 8, 2018
Threads
1
Messages
21
I bought a used murry with a 42" deck, Briggs and Stratton 16.5 HP (engine model 28W707) and the PO did a hack wiring job. So I'm trying to find a wiring diagram, but the sticker on the mower is half way wore off. I hope these picture attachments works. Does any one have an ideal of the model or know of a way i can find out? Thank you.
 

Attachments

  • 20180507_215453.jpg
    20180507_215453.jpg
    94.5 KB · Views: 10
  • 20180507_215441.jpg
    20180507_215441.jpg
    113.7 KB · Views: 9

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
64
Messages
24,647
First a little computer magic
Go back and drag the mower out into the sunlight.
Take some photos of tag at the highest resolution you camera has ( camera is better than a phone ) at different angles.
Go inside and upload the images then play around with the contrast also try inverting the colours as well.
Digital cameras are a lot more sensitive to dirty white on dirty white than your eyes,
The area under where the type was will be less faded than the areas without the type so will be closer to the original colour.

Next , most Murrays are wired according to the std Briggs wiring diagrams.
The wiring schmatics were done by a keyboard jockey with absolutely no idea of what he was doing
But they should be good enough for you to blunder through with.

Later models will have what passes for a wiring diagram will be found in the owners manuals that have a parts section in the back.
Below are a couple from Murray books and the general Briggs wiring diagram

This is a diatribe from some previous answers to people with wiring / stating problems.
Before you do any wiring repairs , remove the blower housing and remove the kill wire form the magneto.
After you have finished check this wire for voltage with every combination of the controls.
If it even thinks it is going to get battery or alternator voltage then control chip in the coil will self destruct and those little buggers are not cheap.

Behind the ignition switch are tiny letters nd they code out like this

B = battery voltage always active
S= Start, gets 12 V when turned to the start position
A = Alternator gets connected to B so the battery can be recharged
L = Lights may be a 12 V teminal with DC lights or ground for AC lights.
M = Magneto should be either open circuit or ground when turned off
G = Ground.

There might be A1 & A2 or L1 & L2 and these just split circuits for things like hour meters , accessory power outlets , hour meters & grounding the alternator to effectively make it a brake when the engine is shut down.

The PTO & brake switches are usually double switches.
One side is live and used for cranking and the other side is ground, used for safety switching.
The switches connect the terminal flat side to flat side ( orange to orange or yellow to yellow )
The PTO & BRAKE switches will have one side connected pin in & the other side disconnected pin in and these reverse when the pin is out.
If you have to replace them make sure the new switches work the same way as JD use an identical looking switch where the contacts are reversed.

The start circuit is a loop,
Fuse > B terminal >S terminal > PTO Switch > brake Switch > solenoid trigger > ground.

View attachment Murray wiring -1.pdfView attachment wiring -2.pdf
 

06compound

Member
Joined
May 8, 2018
Threads
1
Messages
21
Thank you guys for your help. I do not have a better camera, but I'll take some more pictures of it tonight. When i get home tonight I'll look at the back of the ignition and see if its coded at all.

I do have a picture of the wiring that I need a diagram for. There is a red yellow and white that comes from the ignition, black and red that comes from the stator, a gray wire that comes from the bottom of the carburetor and a black wire that comes from the coil.
 

Attachments

  • 20180508_075917.jpg
    20180508_075917.jpg
    144 KB · Views: 2

Boobala

Lawn Pro
Joined
Feb 15, 2015
Threads
200
Messages
7,000
Your enginge code number shows it to be a FEBRUARY 1999 model, ( if the shroud hasn't been changed ) so IF the engine is ORIGINAL to the mower it should be a 1999 OR a 1998, check your ignition switch to see how many terminals it has, ???

The gray wire in your right hand, should go to a connector on the carb. solenoid (bottom of carb.) the black wire in your right hand, MIGHT ... ( should) go to the coil, if so, its the "kill" wire, the RED & BLACK coming down from under flywheel are your stator wires, there should be a diode in one of them, (the RED I believe) I think I have some pics of the elect connectors in my files, .... I'll have to check.....
 

06compound

Member
Joined
May 8, 2018
Threads
1
Messages
21
Your enginge code number shows it to be a FEBRUARY 1999 model, ( if the shroud hasn't been changed ) so IF the engine is ORIGINAL to the mower it should be a 1999 OR a 1998, check your ignition switch to see how many terminals it has, ???

The gray wire in your right hand, should go to a connector on the carb. solenoid (bottom of carb.) the black wire in your right hand, MIGHT ... ( should) go to the coil, if so, its the "kill" wire, the RED & BLACK coming down from under flywheel are your stator wires, there should be a diode in one of them, (the RED I believe) I think I have some pics of the elect connectors in my files, .... I'll have to check.....

Thank you for that info.

The gray wire is connected to the carb, the black wire is connected to the coil, i just need to figure out where they go from there. I'll look for a diagram and FSM tonight.
 

Boobala

Lawn Pro
Joined
Feb 15, 2015
Threads
200
Messages
7,000
You need to remove the ignition switch with it's connector and take a pic of the wiring in the conn. there are several wiring variations on the Murray mowers, some have 5, 6, & 7 terminals depending on the engine, and components, of the various models, without the model number of the mower, it's a lengthy process, have you had this machine running ?? you actually only need 2 wires to "hot-wire" the engine to test it with jumping the starter, most of the wiring is the safety switches. IF you plan on keeping the machine, I would suggest you get the wiring harness either new or used, ... spliced wires and "jury-rigging" usually causes problems later. still looking for those pics I have.............
 

Boobala

Lawn Pro
Joined
Feb 15, 2015
Threads
200
Messages
7,000
Found these pics (finally) anyway these are from my former mower, this particular model used a 7 terminal ignition switch, see enclosed diagram, I hope these pics and the diagram don't lead to confusion on your part (NOT my intent) ... just trying to give you an idea of how different models are wired, The VIOLET & BLACK wires are for the headlights, the YELLOW & ORANGE are the safety switch circuit,NOW without seeing or knowing the model number of the mower or the terminals on the IGN. sw. I'm only guessing, .... need info of your IGN. sw. and it's wires.......

View attachment 37571..View attachment 37572..View attachment 37573..View attachment 37574..DSCN247888.jpg
 
Last edited:

06compound

Member
Joined
May 8, 2018
Threads
1
Messages
21
Yes it was running, but i was getting intermittent spark, which lead me into the wiring. The PO did a garbage job trying fix the wiring. So now i wanna fix it correctly.

I'll dig into more when i get home tonight. I was only able to see one of your pics, the one of the carb. Your carb is different then mine. Yours appears to have screws hold the bowl on while my bowl just twists onto the carb.
 

Boobala

Lawn Pro
Joined
Feb 15, 2015
Threads
200
Messages
7,000
Yes it was running, but i was getting intermittent spark, which lead me into the wiring. The PO did a garbage job trying fix the wiring. So now i wanna fix it correctly.

I'll dig into more when i get home tonight. I was only able to see one of your pics, the one of the carb. Your carb is different then mine. Yours appears to have screws hold the bowl on while my bowl just twists onto the carb.

DSCN1947 (Medium).JPG..DSCN2464 (Medium).jpg..DSCN2465 (Medium).jpg..

I hope you can see these pics I reloaded them ..... NEED PICS OF YOUR SWITCH !!!...11111AAA (Medium).PNG
 

Attachments

  • DSCN2465.jpg
    DSCN2465.jpg
    102.5 KB · Views: 1
  • DSCN2464.jpg
    DSCN2464.jpg
    100.5 KB · Views: 0
  • DSCN1947.jpg
    DSCN1947.jpg
    134.5 KB · Views: 1
Top