b7100 dynamo

ken erickson

Well-known member

Equipment
B7100 hst, 2650 front mount snowblower, L2501 hst qa loader
Nov 21, 2010
1,147
1,856
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Waupaca Wisconsin
I was thinking the nut holding the pulley onto it, not a mounting nut...

now wondering HOW they did it at the factory, in what 15-20 seconds ???
IF not mistaken I think the workshop manual mentions taking the head off when repairing or replacing the dynamo. I assumed when the factory built the engine up this went on before the install of the head. I really did not want to remove the head and replace gasket on a perfectly good running engine. Maybe 85Hokie can confirm that is the case?
 

kubotasam

Well-known member

Equipment
B2410, B7100dt, B7500,Woods BH750,Landpride 2660RFM, Tiller, B2781 Snowblower
Apr 26, 2010
1,204
128
63
Alfred Maine
IF not mistaken I think the workshop manual mentions taking the head off when repairing or replacing the dynamo. I assumed when the factory built the engine up this went on before the install of the head. I really did not want to remove the head and replace gasket on a perfectly good running engine. Maybe 85Hokie can confirm that is the case?
I remember reading that you need to remove the head to replace the dynamo in the WSM/
 
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85Hokie

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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,745
2,551
113
Bedford - VA
I was thinking the nut holding the pulley onto it, not a mounting nut...

now wondering HOW they did it at the factory, in what 15-20 seconds ???

If I memory serves me ......... IF the head comes off or the front timing cover is off - it is easy peasy ....
then again everything is easy ....... from the ground up build.
 

Rodnok

Member

Equipment
B7100hst, MMM, Box Scraper, FEL make unknown, adapted and resurrected from junk
Dec 28, 2015
48
0
6
chattanooga, tn
If I memory serves me ......... IF the head comes off or the front timing cover is off - it is easy peasy ....
then again everything is easy ....... from the ground up build.
Hokie, I got the dynamo off using the flex ratchet. It took me a few trys to figure out how to get the ratchet in and turnanle but when I did it was very easy remove that nut. Now if anyone has a link to a video showing how to disassemble the dynamo I would be very grateful. Alsi, I assume when you say yo drill a hole in that bolt to place a eire in that uou mean straight into the end of the bolt. Is that correct?
 

Jedward

New member

Equipment
B7100 HST, ZD1211 and W5021-SC
May 4, 2011
12
1
3
58
Memphis, TN
Hokie, I got the dynamo off using the flex ratchet. It took me a few trys to figure out how to get the ratchet in and turnanle but when I did it was very easy remove that nut. Now if anyone has a link to a video showing how to disassemble the dynamo I would be very grateful. Alsi, I assume when you say yo drill a hole in that bolt to place a eire in that uou mean straight into the end of the bolt. Is that correct?
I just went through this with mine and I was able to get that nut back on by putting a little grease on the bolt so the nut would stick to it long enough for me to get my fingers in there to start it. Good luck!

Ed
 

85Hokie

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Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,745
2,551
113
Bedford - VA
Hokie, I got the dynamo off using the flex ratchet. It took me a few trys to figure out how to get the ratchet in and turnanle but when I did it was very easy remove that nut. Now if anyone has a link to a video showing how to disassemble the dynamo I would be very grateful. Alsi, I assume when you say yo drill a hole in that bolt to place a eire in that uou mean straight into the end of the bolt. Is that correct?
correct - the wire will be straight in .......... but the wire will come up and around the case
 

Rodnok

Member

Equipment
B7100hst, MMM, Box Scraper, FEL make unknown, adapted and resurrected from junk
Dec 28, 2015
48
0
6
chattanooga, tn
correct - the wire will be straight in .......... but the wire will come up and around the case
Well I git the dynamo off and dissasembled. Simple enuff to just hold in vice and tap shaft through with a socket extension. One bearing is very rough feeling and the other is seized. S can of carb cleaner later and I am ready to assemble as soon as I get new bearings, Thanks to all of you for yhd help!
 

85Hokie

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Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,745
2,551
113
Bedford - VA
Well I git the dynamo off and dissasembled. Simple enuff to just hold in vice and tap shaft through with a socket extension. One bearing is very rough feeling and the other is seized. S can of carb cleaner later and I am ready to assemble as soon as I get new bearings, Thanks to all of you for yhd help!
before placing back on the tractor- place it in a vise and use a drill and socket adaptor and check for AC voltage.

Spin is fairly fast - a Volt meter should read something close to 30 volts AC.
 

Rodnok

Member

Equipment
B7100hst, MMM, Box Scraper, FEL make unknown, adapted and resurrected from junk
Dec 28, 2015
48
0
6
chattanooga, tn
before placing back on the tractor- place it in a vise and use a drill and socket adaptor and check for AC voltage.

Spin is fairly fast - a Volt meter should read something close to 30 volts AC.
Thanks for the tip on testing for voltage. Putting it back on today as it took me a week to get the gasket. Does the gasket require sealant?
 

85Hokie

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Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,745
2,551
113
Bedford - VA
Thanks for the tip on testing for voltage. Putting it back on today as it took me a week to get the gasket. Does the gasket require sealant?
Well.............. there is some debate there - some use the gasket and some use the form-a-gasket goo.

I knew in advance that I could screw up a rubber room and ordered a gasket AND made another copy of that gasket .....just to have!!!

I had to place it on 3 times due to a hairline crack that I did not see - had to buy the entire casing and then I used the form-a-gasket.