75 400 estart with cdi charging issues

[lwb140]

I have a 75 400 Im working on for the 16 rwtc midmount mania. My dad bought this sled new and without a doubt the first sled I ever rode. after converting it to cdi ignition I took it to the 2014 rwtc intending to put a few miles on it. In the parking lot a the whitetail it burnt the regulator completely up , black goo on the belt shield and blew the lights out. recently I installed a hewtech stator and cdi. just goofing around the shop it has already burnt out the headlight bulb at idle rpms. after comparing the 74-5 vs the 76 cyclone wiring diagrams I have unplugged the 3 wire plug on the back side of the light switch which bypasses part of the rectifier when the lights are on. has anyone else dealt with this? I tried to see if there was any info given on the 75 800 x8 cdi conversions with e start but couldn't find anything. any thoughts? wade

[HoosierDeereMan]

Wade,

Check and make sure the ground for the voltage regulator is good and clean.

Troy

[JDT]

Hey Wade,

When you switch from the original points system to CDI on a sled without E-start it is fairly straight forward.

But when you add E-start to the mix you have several issues to deal with.

I was looking over the wiring diagrams and a couple of important red flags pop up.

On the points stator both yellow leads from the lighting coil go into the main harness but if you follow the diagram through one yellow goes back to ground through the jumper connector that is removed when E-start is used. When e-start is added the jumper is removed and both yellows go to the rectifier.

But when you use the CDI stator one yellow lighting coil wire is ALWAYS held to ground via the connector.

There are a few other differences in the lighting wiring and light switch type.

My suggestion would be to rewire the system to match exactly the wiring diagram shown for the 75/76 models w/CDI.

This would include replacing the FWBR with a single diode and the headlight toggle switch.

[harleysportster]

Wade,
I have the wiring diagram for the X8 somewhere. I'll find it for you.

[JDT]

Pat when Deere came out with the CDI conversion kit was there any changes in the wiring harness?

Do you have a copy of the conversion kit instructions? Never seen it.

[harleysportster]

Todd,
The '75 JDX8 started out with points then were changed over CDI during the product year. My X8 had a CDI system on it when i got it. I added Estart to it. I do not have a complete wiring diagram but this wiring diagram illustrates the wiring from the dash to the battery.
http://www.jdsleds.com/tech/wiring/74wiring.jpg
This diagram shows the CDI system of the '75 295S. The major difference between the two is the type of light switch used and ignition switch.
http://www.jdsleds.com/tech/wiring/295swiring.jpg

Hope this helps.

[JDT]

Can one assume that there were no E-start 295's?

[JDT]

I see that the 295 uses a two wire switch for ignition. I imagine it is the same switch but only uses terminals A & B.
(Never worked on a 295S.)

[harleysportster]

I would think that since the 295S was a racing snowmobile, no estart was offered.

[JDT]

Let's assume that there is no changes in the wiring for a moment, even though I think this is not the case.

If Hewtech's stator has a boosted output, ie higher wattage, than the OEM stator than the stock regulator may not handle the extra power.
This may have caused Wade's regulator to overheat and melt. If memory serves the OEM regulator was rated for 75 watts.

Now if you ran with the lights on all the time there would probably be no problem if it was a higher output stator.


So Wade my question for you is when you started your sled in the parking lot did you have the lights on or off??

[JDT]

Many newer sleds run over 200 watts stators an of course larger regulators with finned aluminum heat sinks.

[lwb140]

first off thanks for all the thought you guys are putting into this for me

in the hotel parking lot I had the lights on . they were on during warm up . however after the rpms came up shortly after I started moving the lights all went out !! and before the first lap .the big burnt smell came pouring out from under the hood.


2 big things first off , there was no battery in the sled , I ran my cyclone for years with no battery and thought nothing of it
secondly . this was with a bone stock 77 stator , I just changed to the hewtech yesterday. after stewing and fussing I didn't feel comfortable leaving that stator in it assuming things prolly got super hot in under there. wanting to get this fixed before I bake my fresh hewtech stuff. did unplugging the 3 wire plug behind the light switch change anything ?

also I did put a new battery in it !!

I have considered building a harness like the 76 sleds but keep thinking id like to molest this sled as little as possible if there is a simple fix . thanks again wade

[harleysportster]

If I remember right, I unplugged the estart harness at the big connector and put the OEM jumper wire back in when I removed the battery.

[JDT]

Wade I am confussed.

There are five wires shown in the diagrams on the headlight switch. You mentioned three, twice.

Without a battery installed there is very little load on the charging system. This can cause regulator failure.

And yes Pat without the jumper installed lighting will not work.

Really would like to see the update X-8 diagram used with the CDI conversion.

You have it right Wade? Can you scan it and post it or send it to me?

[harleysportster]

Wade,
Do you have the oem double pole lighting switch installed?