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Is my Mark VII motor/switch wiring correct?

Posted: Mon Aug 22, 2016 4:18 pm
by n240sxle91
I bought my Mark VII earlier this summer. I believe it is in pretty good shape, but it has a few things that I want to take care of before I start to use it.

One of the things that didn't seem to work right was the "reverse-stop-start" buttons. The reverse button didn't seem to press correctly. I bought a replacement off of an auction site, and today I finally had time to try to install it. However, after I removed the switch I found that it worked just fine. The previous owner modified this Mark VII's speed control, and it looks like there was some work done on the Motor/Switch wiring too. So, I'm worried the previous owner might have done something wrong with the wiring. He has a splice in one of the wires, and I can't figure out why. Could you guys look at the following pictures and see if it looks right to you?

Also, I have a quick question about the Mark VII's key. Am I right in assuming that it is designed to only allow Forward if it's turned one way, and Reverse if it's turned the other way? Again, because modifications have been done I'm not sure if mine is setup correct.

Thanks!
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Re: Is my Mark VII motor/switch wiring correct?

Posted: Mon Aug 22, 2016 4:37 pm
by JPG
It cannot possibly be correct as two of the terminals that control start direction are bare.

Yes the key acts as an interlock to prevent too fast a transition from one direction to the other(the direction is ONLY determined at start from rest)(i.e. start relay contacts closed).

You have the GE motor with start relay.

I do not have a wiring diagram for it.

I do have one for an a.o.smith with start relay.

I think we can decipher it but I need to know all the wire colors.

There should be(I think at this point) blue,white,orange, purple,red,black and possibly brown.

Determining color from the pix is unreliable.

Do you have a way to measure resistance/continuity(volt-ohmmeter)?

Re: Is my Mark VII motor/switch wiring correct?

Posted: Mon Aug 22, 2016 4:45 pm
by n240sxle91
Thanks for the help! It didn't look right to me, so I'm glad I asked!

Yeah, I have a volt meter. I'll try to check the wire colors later today.

Re: Is my Mark VII motor/switch wiring correct?

Posted: Wed Aug 24, 2016 3:01 pm
by n240sxle91
I haven't had time to look at the wiring yet, but I was wondering about why the previous owner would disable the ability to reverse the shopsmith. Do you think it has anything to do with the Mark V speed control mod he did? Would reverse somehow have a negative impact when using a Mark V speed control on a Mark VII? I'm not certain, but I think he also replaced the sheaves with Mark V ones.

Thoughts?

Thanks

Re: Is my Mark VII motor/switch wiring correct?

Posted: Wed Aug 24, 2016 3:14 pm
by JPG
n240sxle91 wrote:I haven't had time to look at the wiring yet, but I was wondering about why the previous owner would disable the ability to reverse the shopsmith. Do you think it has anything to do with the Mark V speed control mod he did? Would reverse somehow have a negative impact when using a Mark V speed control on a Mark VII? I'm not certain, but I think he also replaced the sheaves with Mark V ones.

Thoughts?

Thanks
It is possible the switch became faulty(a not uncommon occurrence). The sliding contacts loose tension, poor contact results and the heat generated exacerbates that by removing the tempering.

As for the Mark V 'running backwards', I do not see a problem with that. The Mark VII only differed in the manner in which the control sheave was moved. The sheaves are essentially the same with a few dimension changes(hub length primarily).

Re: Is my Mark VII motor/switch wiring correct?

Posted: Wed Aug 24, 2016 3:19 pm
by JPG
n240sxle91 wrote:I haven't had time to look at the wiring yet, but I was wondering about why the previous owner would disable the ability to reverse the shopsmith. Do you think it has anything to do with the Mark V speed control mod he did? Would reverse somehow have a negative impact when using a Mark V speed control on a Mark VII? I'm not certain, but I think he also replaced the sheaves with Mark V ones.

Thoughts?

Thanks
It is possible the switch became faulty(a not uncommon occurrence). The sliding contacts loose tension, poor contact results and the heat generated exacerbates that by removing the tempering.

As for the Mark V 'running backwards', I do not see a problem with that. The Mark VII only differed in the manner in which the control sheave was moved. The sheaves are essentially the same with a few dimension changes(hub length primarily).

Re: Is my Mark VII motor/switch wiring correct?

Posted: Wed Aug 24, 2016 3:33 pm
by n240sxle91
Thanks for putting my mind at ease! I was starting to worry that when I wire it up to run in reverse something would fly apart inside and ruin it!

Thanks again!

Re: Is my Mark VII motor/switch wiring correct?

Posted: Sat Apr 08, 2017 5:07 pm
by n240sxle91
OK.... I'm back! Last summer ended up being really busy and I didn't have time to work on my Mark VII. Then winter happened. :( Now that it's warmed up enough for me to work outside on my Mark VII I want to get this going!

So, after looking at my modified Shopsmith some more I noticed my motor doesn't have the same specs as the other ones listed in the Mark VII manual. My motor is a GE WITH an external relay. The manual only lists the A.O. Smith as the one with an external relay. Also, my motor is 13.5 amps. The motors in the manual are listed as being between 12.5-12.6 amps.

So, here's my question. Do you guys think the reverse on my switch was disabled because they put in a different model motor that isn't capable of going in reverse?

As always... thanks for your time and help! I really appreciate it!

Steve

Re: Is my Mark VII motor/switch wiring correct?

Posted: Sat Apr 08, 2017 10:40 pm
by JPG

Re: Is my Mark VII motor/switch wiring correct?

Posted: Sat Apr 08, 2017 10:52 pm
by n240sxle91
I'm sure you're pointing out something obvious,but I'm not seeing it. :)

I know my wiring is currently wrong, but my theory is that that was intentional by the previous owner because they put in a motor that isn't capable of reverse. I looked up the motor's model number and didn't find anything, so I can't prove that this motor isn't capable of reverse, but it seems to make sense since it looks like reverse was deliberately disabled.

Thoughts?