failed rectifier. possible replacment

Well, I had my 1980 kz1000e2 shaft up and running. then this morning on my way to work the bike just shut down. which was caused by a burnt out main fuse. I tore into the bike and checked all wires for shorts. find a possible one fixed the area. then when i started the bike and had it idling the head light started getting brighter then the bike just shut down again, this was at a constant idle. the main fuse was found to be blown again.

This makes me think my rectifier is bad.

Which one of these is the better one.
z1 www.z1enterprises.com/Rectifier--Regulat...750-KZ1000-1731.aspx
looks to be a direct fit.
accel store.prestoliteperformance.com/regulator-kaw-kz650-1000.html
says it fits, has the same wiring but is almost a 4th of the price.

www.electrosport.com has a nice troubleshooting page and:
www.oregonmotorcycleparts.com is another source for rectifier/regulators

You may have "Smoked" a phase or two on the alternator stator, so do this check:

Alternator Testing For the Older 4’s(Z1’s,Kz 900’s, Kz1000’s,Kz1100’s and GPz1100’s).

To check to see if the alternator is working you need to follow these simple steps:

1. Fully charge the battery as this will be the power source during this test.

2. Disconnect the Regulator/Rectifier at the plug that has the six wires in it.

3. Start the engine and let it warm to operating temperature.

4. If you're worried about overheating, position a large fan for cooling the engine.

5. After the engine has reached operating temperature, have a helper assist you, and using a multi-meter, read the output at the three yellow wires (or the alternator output wires)at the disconnected connector.

6. Raise the engine speed to 4000 rpm, and see what the three YELLOW wire combinations(or any alternator output wires) are(1-3, 2-3 & 1-2). The output will be around 50 Volts A.C.(Alternating Current). BE CAREFUL, AS THERE IS A SHOCK HAZARD HERE!!

7. If any of the combinations are low or non-existent, the stator(wire windings) are bad and must be replaced.Some of the older Z1’s and KZ900’s were reported to be phase sensitive, so check the wire colors carefully.

8. Using an OHMETER, Check the three wire combinations again, looking for a reading of 0.36 - 0.54 OHMS. If the readings are above or below, the stator may be bad and need replacement. Also check from any of the three YELLOW wires to ground, this will show if arcing took place. Check only with the engine off !!

9. Before ordering a new stator, check the connections from the stator as there are electrical "Bullet" connectors that may be damaged or dirty.Inspect the wiring for signs of shorting or overheating too. www.z1enterprises.com sells replacement rubber grommets for the alternator output wiring, they get hard and could leak oil after a while.

10. Check the wiring coming out of the grommet as there have been situations where the wires were damaged causing a short(I.E. twisted together with insulation damage).

11. The sprocket cover will have to be removed to access the electrical connectors coming from the alternator, the left foot peg assembly and shifting lever will have to come off also.

Alternator Stator Replacement On the Older 4’s
Source for replacement Stators

A. www.electrosport.com (They have a trouble shooting page)
B. www.customrewind.com
C. www.rmstator.com
D. www.ricksmotorsportselectrics.com
E. www.regulatorrectifier.com

1. If by testing either by checking the output voltage from the stator or by using and ohmmeter for resistance and the stator is determined to be bad, replacing the stator is not a difficult job.

2. The motorcycle owner should have on hand a replacement alternator gasket as it will tear on removal and leak if reused.

3. Put the bike on the center stand if possible and lean it to the right to minimize the oil volume that could come out when the alternator cover is removed.

4. Have selection of Metric wrenches and sockets along with Metric Allen keys to be able to accomplish this repair. ¼" and 3/8" ratchets and extensions may be needed along with Allen bits.

5. Remove the gear shift lever, the sprocket cover and possibly the left foot peg assembly.

6. A catch pan for what little oil will be lost should be positioned under the alternator on the left side. Newspapers will soak up any oil lost or some kitty litter will do as an absorbent.

7. Remove the alternator cover fasteners, some bikes use a socket head cap screw(Allen type) and others use the Phillips head type, the #3 screwdriver bit fits best for those. Use a small dish or can to collect the removed fasteners from the parts to prevent loss/damage.

8. The alternator stator is secured to the inside of the cover usually with three Allen headed bolts, Some bikes may have Torx style fasteners, Remove them and disconnect the three yellow wires that have bullet connectors on them from the bundled wires inside the sprocket cover.

9. If your bike has some color other than yellow for the alternator output wires, make note of what goes where as the older Kawasaki’s were phase sensitive in regard to the regulator/rectifiers.

10. When installing the replacement stator, clock or position the output wires and grommet so they fit into the small port under the alternator cover without being pinched or damaged.

11. Tighten the three Allen or Torx fasteners, securing the replacement stator to the cover. I like using the BLUE Loctite # 242 for hardware that can be removed with hand tools.

12. Remove the old gasket from the mating surfaces of the alternator cover and engine case by scraping with a piece of sharpened plastic like Lexan or Plexi-glass as these will not gouge the soft Aluminum Cases. Avoid using a metal gasket scraper for this.

13. Position the alternator cover, checking for pinched wiring and install the fasteners with a little silver anti-seize on the threads, tightening to the correct torque.

14. Connect up the output wires to the mating female bullet connectors and while you’re in there, check the routing of the wire bundle that runs through there.

15. Inspect for signs of heat damage to the wire insulation and vibration damage too.

16. The side stand switch, neutral switch, and oil pressure switch wiring are all bundled with the alternator output wiring running above and behind the engine output sprocket. This bundle runs in a channel as it goes up toward the various electrical connections.

17. The regulator/rectifier plug on the 80’s bikes usually has six wires in it:

A. One (1)WHITE with RED stripe, this is the bikes main power wire usually 12 gauge in size.

B. One(1) smaller Brown wire, probably 18 gauge or so, the voltage sense wire for the regulator/rectifier, helps keeping it from overcharging the battery.

C. One(1) BLACK with YELLOW stripe wire, part of the ground circuits, maybe 16 gauge in size.

D. Three(3) YELLOW wires, maybe 14 gauge in size, the alternator output wires going to the regulator/rectifier which converts the Alternating Current(A.C.) to Direct Current(D.C.) using rectification, producing the power to run the motorcycle and charge the battery.

18. Reinstall the sprocket cover, again checking for pinched wires before tightening. Install the shifter on it’s splined shaft checking for proper location, and the left side foot peg assembly.

19. Except for the minor oil spill and reluctant fasteners, it’s not a very difficult job to do.

LoudHVX has a diagram on here where you can acutally build your own rectifier if your regulator is still good. I did this - cost me about $20-$25 with parts from the local Radiohack and it works great. I'm saving up my pennies until my regulator goes to buy the all-in-one jobby.

If the bulb was getting brighter, it's more likely the regulator, but it would vary with speed (as the generator creates more energy as it goes faster).

I would sit down and test the battery (take it to a shop that tests them or swap in a spare) and the voltage at the battery per your service manual to see what's going on before deciding that the rectifier is the issue.

The rectifier converts A/C to D/C and feeds the battery.
The regulator prevents the generator output from going above a certain amount of voltage.

MFolks wrote: 7. If any of the combinations are low or non-existent, the stator(wire windings) are bad and must be replaced.Some of the older Z1’s and KZ900’s were reported to be phase sensitive, so check the wire colors carefully.

A bit simplistic, really. It could be a short or break in the wiring loom from the alternator to the connector panel, too.

well I tested the stator/alt and it checks out. I am now thinking its my regulator that is bad. its the metal finned box under a metal panel on the right side cover. kwaw lists the part as the voltage regulator. but the part says rectifier so I'm thinking its an all in one system.

I tested it and its resistances where not in the range the manual says which makes me think it is bad.

Also i traced the wires and found no shorts/breaks/or several corroded connections.

well looks like it wasn't a failed rectifier after all. Turns out when I replaced the cam cover gasket I pinched the horn wire so where. its one of those things that once u realize u fell really dumb.

Thanks for the help I tested every thing else on this list so now I know they area ll good.

On these horns, they are "Hot" and the button gives it the ground to make noise. Kinda backwards to how most electrical circuits I've worked with in the past....

Fortunately or not your short didn't probably hurt the R/R, you might want to check all the wiring from the short backward to be sure you don't have a partially melted horn button or connector some where.

Just curious, how long ago did you do the cover?

I did the cover like the night before around 10pm and I started the bike when it shorted around 6 am.

I check over the whole harness and I luckily didn't damage anything else.