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Discussion Starter · #1 ·

I've been on the Crumbliss site and they don't seem to have an archive of material on old machines and I was hoping someone out there had a model 1836 that could post some pictures of the pages of the manual for one of these. I'd mistakenly thought the instructions were stuffed up inside it when my old buddy gave this to me, but it wasn't what it appeared to be.

Trying to figure it out I can tell a good one from a bad one, but don't know if its being done correctly or not. This guage says amps, but I'm thinking without it running, it's reading the applied voltage from the 12v battery being used to test the alternator. When you run the machine with the voltage applied, the 110v motor pulls down dramatically and this needle goes up a few notches on the scale. I'm just assuming it's additional drag placed on the motor by the alternator now putting out amperage into the battery. But I don't know. I know there is no change when testing a known bad one and there is when testing a known good one. This is the higher reading while under load. The lit lamp signifies the dash light when you turn on the key and the alternator isn't yet producing output...the light goes out as soon as it sees output.

Taking the bad one apart and testing all three windings across all combinations of all three in the stator, they have the same ohm reading, meaning they are not shorted or open and reading each individual to ground reads nothing, meaning they are not grounded. So the stator is good.

Pulling the diode trio, shows no continuity on any of the three back to the long side. A diode will allow electron flow in only one direction, so to be good, you should test from the long one to each of the three diodes and with the leads one way, you should read a high resistance and then you reverse the leads and you should read a low resistance...No reading at all means an open diode. Guess what !!! This one reads bad. That's good.

Checking the rotor across the parts that come in contact with the brushes, you read a few ohms resistance on a good one. My meter looks wanky here but it really read 2.8 ohms numerous times. Then checking each to ground show the windings good if there is no continuity.

To check the rectifier, test between the heat sink grounded body and each of the three terminals that the stator windings hook to. Then reverse the leads and perform the test again...if the readings are the same, the rectifier is bad. Then you have to do the same test between ground and the other two winding ends. Of course this is after you have proved the stator windings are good to begin with. A good rectifier bridge will give you readings similar to a good diode trio, one higher and one lower reading on all the combinations of the three.
See the brushes jumped out of the brush holders when the rotor (field) windings are removed??? Well, there is a convenient little hole in the back of the alternator that you can stick a little wire in to hold the little buggers in place during re-assembly. Try as I might, I couldn't hold the test probes correctly with one hand and take a picture with the other so hopefully you could figure out what I was trying to describe.

There !!! The brushes are back in place, the wire is visible, just slide it down pretty close to the inside brush holder as you slide the rotor back into the bearing. This one will be totally disassembled and if the parts can be found reasonably, it will be thoroughly cleaned and new bearings installed with the new diode trio and low rpm exiter... keeping my fingers crossed here.

When done, pull out the little brush retaining wire to allow the brushes to come back in contact with the rotor and should be good to go. Make sure you don't rotate the shaft until the wire retainer is removed, because you may damage the carbon brushes...don't ask how I know, but accidents do happen. So now if I REALLY know what I was doing, I'd be happy...but it's like anything, if it's already broke you usually can't hurt it by taking it apart can you?
I am really hoping someone can lead me in the right direction on the Crumbliss model 1836 information though, it would make my life a lot easier.....

A disclaimer here, please don't take all this to the bank as 100% good info as I just duplicated tests shown me by my old timer buddy that gave me the machine. In other words, I may not have listened too good and may have gotten something wrong. But is sure sounded good, didn't it ??
 

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Maybe try contacting them. Sometimes they might have something hiding in the bottom drawer of their file cabinets.
I used to use tooth picks to hold the brushes instead of wire. (been there, done that)
 

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nice looking unit.

I've used an almost identical one that came out of an old napa.

the a/b circuit switch is for MOST generators.. though some old alternators you tested as a B circuit generator. has the selectable field switch.. the arm/gen and field and ground hookups.

I see that tester is pretty much setup to test only delco 10 series alts probably.

it's got what looks like the sense and excitation plug and the 'dash lamp'

a running reverser switch.. and both test modes for alt and gen.

the one I used had dual gauges for amps and voltage.. that one appears to only have a shunt amp meter. you can see field pull, and then output current probably..
 

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Discussion Starter · #4 ·
soundguy said:
nice looking unit.

I've used an almost identical one that came out of an old napa.

the a/b circuit switch is for MOST generators.. though some old alternators you tested as a B circuit generator. has the selectable field switch.. the arm/gen and field and ground hookups.

I see that tester is pretty much setup to test only delco 10 series alts probably.

it's got what looks like the sense and excitation plug and the 'dash lamp'

a running reverser switch.. and both test modes for alt and gen.

the one I used had dual gauges for amps and voltage.. that one appears to only have a shunt amp meter. you can see field pull, and then output current probably..
You're probably right, but to figure it out for sure, I still need the manual. I'm sure they're still in business, like prwttsh said I will give them a call.
 

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Wow! you electrical wizards amaze me!
I do agree with the part that if its already broke you cant hurt it by taking it apart:)
Regards,
Chris
 

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Nice walk through Wendell, really helps with visual aids. :D
Felt like I was back in "vacational" school (yep, that's what we called it :cool: )
watching a film strip and reading along with the voice on the reel to reel or cassette.
Remember those ??
Hope you find the book of mistakes for your tester.
Dad had a tube tester someone gave him when I was about 6-10. He would bring a television set home from someone
at work and fix it for them. Then he got board with it and gave it to someone else. Was fun to play with though. I guess
it's what got me interested in electricity, and the fascinating career that led to. ;)
 

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Discussion Starter · #9 ·
soundguy said:
have you ever seen an old tube tester. I had one out of a walgreens.

lots of lil lamps and switches inside.. :)
Never played with one, but a buddy's dad uses to come test our Motorola tv tubes back in the 60's occasionally. If I had a nickel for every tv or radio vacuum tube I've shot with a .22 I could buy us all lunch though.

Yeah Dave, I remember those narrated slide shows too.....by the way, did I put you to sleep just like the monotonal narrators voice ???? :lol: :lol: :lol:
 

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It's a long shot, but I see some Crumbiss gear on ebay- maybe contact a seller & see if they have the manual, & would sell a copy/scan? Even a similar model might get you in the ballpark.

Other possibility might be to check with high school or community college shops.... someone out there has a manual! :)

Good luck!
 
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