Re-wire for my 702

[stevasaurus 22,764]

I use my 702 for mowing, not a large lawn, takes about 20 minutes.  Last year, I noticed a sluggish turn of the starter/generator.  I knew the battery replacement was long over due, so I replaced it last fall.  The tractor still ran and started, but I could still see some smoking coming from around the key switch.  It has set all winter, as I use the 857 for moving snow.  I am ready now to tackle the issue.  I pulled up the wiring diagram, but I have the conversion of the HY-2 which moves the wires around the switch.  The HY-2 put a sheet metal thingy on the side of the tower, out of the way of the canister that stores the hydraulic fluid'   I do not have the key with a starter button.  Not a big deal.  I have what is there and it works.  I am going to check wires and replace them (12 gage)??...and 6 gage where the diagram shows.  I may have to open the starter/generator and see how the brushes look and the magnets.  I kind of think some grounds are bad.

   There are a lot of 702's out there.  My plan is to take lots of pictures and document this process.  I could also use a little help.    

   

[Moparfanforever 851]

Sorry I can't help with the wiring , but looking forward to seeing how you do it. 

[ebinmaine 67,590]

20 minutes ago, stevasaurus said:

open the starter/generator and see how the brushes look and the magnets

If you've even begun to consider this you should absolutely do it. 

 

 

12 gauge is good for most everything. OE is likely 14 gauge. 

 

I use 4 gauge for my homemade battery cables. 6 really should be fine.  

 

If you don't already have the wire, try to find full copper. Not CCA. (Copper Clad Aluminum.)

 

If you'd like a few feet of 14 gauge 7 conductor trailer wiring harness I'd be happy to send some.  

It is NOT original. 

That's what I use to rewire all of our Horses.  

 

Looking forward to seeing this.   

[ri702bill 8,327]

The problem with the OE 702 wiring is that all the current for starting runs thru the 2-terminal push button switch - the key switch just controls the coil circuit. I have changed to the later solenoid, using the push button to activate it, to cut the amperage (and resistance) thru the button. Did similar to the 854 8 speed...

Bill

[squonk 41,150]

@stevasaurus The starter draws around 65 amps when cranking and inrush is close to 85. I would run 4 ga. cables to the battery, genny and switch if you got room.

 

BATTERY CABLE SIZE	50 AMPS	100 AMPS	150 AMPS	200 AMPS	300 AMPS
6 GAUGE (AWG)	11.8 ft	5.9 ft	4.4 ft	2.9 ft	2.2 ft
4 GAUGE (AWG)	18.8 ft	9.4 ft	6.3 ft	4.7 ft	3.1 ft

Edited April 22, 2022 by squonk

[953 nut 55,297]

56 minutes ago, stevasaurus said:

I am going to check wires and replace them (12 gage)??

With the exception of the battery/starter wires you can use 16 gauge. Auto parts stores all sell primary wite in short rolls.

I agree with @ri702bill about installing a solenoid and a 103 990 ignition switch. This drawing is what I would use to do the wiring. You should be fine with the 6 gauge battery wites because the runs are so hort that voltage drop isn't going to be a problem.

[pfrederi 17,741]

Whether you go 6ga or 4 ga spend a few bucks and get the extra flexible cable.  So much easier to route it an hook it up puts much less strain on the switch terminal

 

 

[squonk 41,150]

Another thing, when it's apart, Take the generator mounts off of the engine and clean the mounting surfaces so you don't lose any voltage because of rust and dirt. When I built my engine run stand I experimented with paint, rust and dirt on a mounting surface and dropped .6v just with a rusty lower genny mount.

[953 nut 55,297]

Good point Mike, I have started running the ground cable directly to the S/G attachment bolt to be sure there is good continuity.

[ebinmaine 67,590]

1 hour ago, pfrederi said:

spend a few bucks and get the extra flexible cable

That there is good advice.  

 

 

1 hour ago, squonk said:

rusty lower genny mount

 

47 minutes ago, 953 nut said:

Good point Mike, I have started running the ground cable directly to the S/G attachment bolt to be sure there is good continuity.

 

Thanks for bringing that up boys. 

I'm not sure I was aware of that being a bad ground point.   

[JPWH 6,040]

@stevasaurus I found that I could buy a cheap set of jumper cables cheaper than I could buy single strand battery cable by the foot.

Jay

[953 nut 55,297]

1 hour ago, JPWH said:

@stevasaurus I found that I could buy a cheap set of jumper cables cheaper than I could buy single strand battery cable by the foot.

Jay

Need to be a picky shopper there, so many jumper cables on the lower end of the price list are copper plated aluminum wire. Just one example from a store many of us shop at.

https://www.tractorsupply.com/tsc/product/forney-52881-6-booster-cables-16-ft?cm_vc=-10005

[JPWH 6,040]

Some of the copper clad al are more expensive than fine strand copper. I found fine strand copper at Wally world for around $20.00. the ends are junk but the wire is good.

[953 nut 55,297]

Good to know, got to shop around. I had the set from TS in my cart before I read the fine print and saw the materials list.

[Racinbob 11,088]

Steve, first you stated that you do not have the starter button. That tells me it's been (not surprisingly) rewired before. The original key switch on a 702 won't work as it's only a SPST maintained contact. It would have to have been replaced with a switch that not only has the maintained contacts but the momentary start contacts. If the proper switch wasn't installed that can handle the starter load that would explain the smoke. My 854 originally uses a 4988 switch designed to handle the starter load. It's still available but I don't remember the new number but it's available. But the bottom line is that a solenoid is a better set up. I originally rewired my 854 using a new (pretty expensive) replacement for the original 4988 but have since rewired again using a solenoid. 

 

As far as wire size you don't need 12 ga, Like Richard said 16 ga in big enough but my preference is 14 ga. #6 is plenty big enough for the starter wires. As mentioned use the fine strand for flexibility (think welding cable). There more than one guy on Ebay that will make the cables color coded and to your length, install the size terminals you need and heat shrink. Delivered they cost less than you can buy the cable alone for. 

 

As mentioned several times and something you know, the connections are the critical. Running bigger wire won't make up for a bad connection. 

 

Using store bought jumper cables is an option. I purchased two sets of the Everstart cables from Walmart for a somewhat unique starting set up on our home generator but they are only copper clad. If they don't say 100% copper they most likely aren't. That being said copper clad doesn't make them bad. 

Edited April 23, 2022 by Racinbob

[squonk 41,150]

Heavy switch:

 

• Cole Hersee Part No.: 95521-B-BX
• Package Type: Boxed
• Number of positions: 3
• With anti-restart: No
• Actuator: Hencol Key
• Positions: Off - Ign - Start
• Spring return to Off Spring Return to Run
• Terminals: 3 Screw
• O-Ring seal in stem: Yes
• With harness: No
• With key boot: No
• Ignition/Run: 25A/12V DC
• Start: 70A/12V DC
• Removable key: Key Removeable in Off Position Only
• Case material: Plated steel
• Sealed terminal insulator: Yes
• Ground terminal: No
• Mounting stem: 5/8 (15.88mm)
• Contacts: Silver
• Mounting panel thickness: 1/8 (3.17)
• Ignition-proof: SAE J259

[Lane Ranger 10,968]

Also check for corrosion on the regulator wiring tabs.  Especially the GEN tab if underneath your regulator.  I had one pretty corroded on my 754 tractor but it was not running and sat for years.  The A and F teapots terminals on the Starter generator should be real clean and free from paint, grime etc.  plus using brass flange nuts makes a better connection.  

[squonk 41,150]

I always "upsize " cables when I can. Here's why:

 

I had a 84 Honda Goldwing. These are known for hard starting when hot. I had to get push started by my riding buddies a couple of times. Embarrassing! I bought a brand new 450 CCA battery, new starter and all new 6 ga. cables. All OEM. It improved things but I still had starting issues when hot. Took the cables off an had a set of 4 ga. cables made up to match the length and ends. Put those on and it felt like the starter was going to flip the bike over it cranked so fast. hot or cold.

[tunahead72 2,424]

1 hour ago, Racinbob said:

... There more than one guy on Ebay that will make the cables color coded and to your length, install the size terminals you need and heat shrink. Delivered they cost less than you can buy the cable alone for...

 

Bob, are there any sellers in particular you could mention?

 

[squonk 41,150]

I have a shop near by that rebuilds starters and generators that make mine.

[WHX?? 48,828]

2 hours ago, Racinbob said:

guy on Ebay that will make the cables color coded and to your length,

Yah and his name is @Achto. And they are nice ones and end with a four letter word starting with F. for you, maybe even Tuna. I'm sure he would make some for ya but not Squonky....

Dave Brown @new2horses has the replacement 70 amp switch if you don't want to go back to the OEM heavy start switch.

 

Better yet if you can make it till Portage show bring her up and we'll rewire it there. Give us something to do other than drink.... 

 

My 70 amp switch smokes abit too but only when the SG locks up due to a non-acr cam.

 

Hosen says letter smoke! 

Edited April 23, 2022 by WHX??

[Racinbob 11,088]

55 minutes ago, tunahead72 said:

 

Bob, are there any sellers in particular you could mention?

 

 

No. I've probably ordered 5 or 6 times but there's a bunch that make them. I just tried to search my orders but Ebay isn't letting me. Just do a search for battery cables and you'll have several to choose from. 

[stevasaurus 22,764]

Holy Starter Switch Batman !!!  I started this thread yesterday, come down here this morning and I see all this OUTSTANDING information.  Got an 80 degree day today.  I was going to pull out the 702 and take some pictures, now I have to pull it out.  Thanks guys.

   I do not have the push button start on this horse.  I have a feeling the HY-2 was added after the horse was bought.  I wonder if the Dealer may have re-wired it at that point.  

[stevasaurus 22,764]

Pictures...as you can see, plenty of bad spots.  The ignition is 3 prong and uses a Wheel Horse key.    It does have a working cigarette lighter above the ignition.  It had lights, but I removed them.

 

 

 

 

 

 

 

 

 

 

 

 

 

[squonk 41,150]

You got some big heavy cables there, That one to the gen itself looks a bit iffy. A good clean up of all the ends will help a lot. I'd be willing to bet the innards of the switch are ready to give up the ghost being as old as it is.