Blown engine... are these models interchangeable?

cpurvis

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You need the wiring diagram for the engine and wiring diagram for the mower.

Then start matching things up.
 

Team_Dub

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You need the wiring diagram for the engine and wiring diagram for the mower.

Then start matching things up.

Well, if I could find those, that's what I'd be attempting to do.

I was hoping someone with more familiarity with these would have a straightforward answer.
 

Boobala

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Well, if I could find those, that's what I'd be attempting to do.

I was hoping someone with more familiarity with these would have a straightforward answer.

HEY T-D .. I'm workin on it 2 ......... new engine wire colors screwin me up, so far ( I'm using NEW MODEL ENGINE ( 31R907-0007-G1 ) is that an AFFIRMATIVE of what U have bought ..?? looks like it's a 5-9 Amp. TRI-CIRCUIT alternator & regulator... TRYing to find the correct diagrams, for both engines, AND the mower....... just hang in there, these things take time.... Boo
 

bertsmobile1

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Two options.
1 ) take the blower housings off and swap the electrics
2) take the blower housings off and check where everything hooks up.

The latter engine has a real rectifier/ regulator
the earlier one has a single diode in the red wire on the engine side of the plug

Under the blower housing there are 2 wire. one goes to the magneto the other to the carb solenoid.
Pull the magneto wire off , hook the wires up and check that the magneto wire never has voltage, it is a ground wire so should be either ground ( engine off ) or open ( engine on ).
 

Team_Dub

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HEY T-D .. I'm workin on it 2 ......... new engine wire colors screwin me up, so far ( I'm using NEW MODEL ENGINE ( 31R907-0007-G1 ) is that an AFFIRMATIVE of what U have bought ..?? looks like it's a 5-9 Amp. TRI-CIRCUIT alternator & regulator... TRYing to find the correct diagrams, for both engines, AND the mower....... just hang in there, these things take time.... Boo

Yessir, 31R907-0007-G1 it is.

I'm done messing with it for the night; just had to push-mow our sled hill of a front yard. Gonna have a couple beers and try to not die.

Thanks, Boo.

:drink:
 

Team_Dub

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Two options.
1 ) take the blower housings off and swap the electrics
2) take the blower housings off and check where everything hooks up.

The latter engine has a real rectifier/ regulator
the earlier one has a single diode in the red wire on the engine side of the plug

Under the blower housing there are 2 wire. one goes to the magneto the other to the carb solenoid.
Pull the magneto wire off , hook the wires up and check that the magneto wire never has voltage, it is a ground wire so should be either ground ( engine off ) or open ( engine on ).

Thank you for the info.!

I may have to go that route tomorrow.
 

bertsmobile1

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Been trying to decipher this, but the heat stroke is making me really, really dense.

http://www.smallenginesuppliers.com/html/engine-specs/briggs/briggswiringexplanation.pdf

That is quite an old article.
On your original wiring you had 2 wires off the alternator.
A red wire with a diode in it to make it DC ( thick bit near the plug ) and an AC black wire which went to the lights.
The new engine has a DC only output cause it has the real rectifier on it in place of the single diode.
So the red from the rectifier goes to the red wire on the old plug hiding behind the dip stick tube.
For the time being you can forget the old black ( AC ) wire as it only goes to the headlamps and to get them to work might require a bit more wiring.
Then you only need to hook up the magneto kill wire and the fuel solenoid wire .
The grey wire on the new 2 pin plug should be the solenoid wire and the black wire should be magneto kill wire, remove them all together as you will be using the old wires.
Run the old black magneto wire up to the magneto and the old solenoid wire to the solenoid, they should go behind the starter not in front of it.
Now cut the 2 wire plug attached to the old 4 pin plug off near the 2 pin plug so you have some wire to work with .
Cut the white plug off the red wire coming out of the rectifier get a single connector plug and join the 2 red wires together using a plug of some sort .
Resist the temptation to solder them together because if the rectifier fails you will have to cut the wires again & eventually they get too short to work with.
From here you are good to mow.

This will only leave you with the lights ( if you want them ) and for them you have to do some rewiring as they are always in circuit ( you turn them on by grounding them ) and can either drain the battery or worse pump power to the magneto when the mower is turned off.
To work out how to wire them in I need to have a look at the connections on your ignition switch.
 

Boobala

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T-D Tried in vain to locate your mower's wiring diagram, this is now become a head scratcher, perhaps the easiest, fastest way is to do this is per Bertsmobile1's suggestion, and swap the stators out, and the solenoid and kill wires (old to new engine, and remove the regulator from the new engine, I think everything should fall into place then, I will continue to look if you want, but I'm done for the night on this issue, ... Boo
 
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Hey Boo I need a favor ..................

While I am on vacation, you think you could Be Bop back and forth a couple time a day to check on my house for me ?????

I'll leave the spare key in the normal place and Missy cooked a shrimp and crab stew tonight and we got the leftovers in the icebox.... The one in the spare bedroom, not the main one in the kitchen....

BTW I think Missy only took one glass of wine out the bottle of homemade Muscadine wine.... I put the cork back in real tight so it will be good at least 3 to 4 days..........

Eat all you want and we left you a lot of potato salad also... Eat all that too.... It will go bad if you don't......

Merci Mon Ami..........

We bringing back a few ice chests of shrimp if the tide is right..........

Plus Tard ..............
 
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