Jlo 400 engine problems

[nate52]

i have a 400 cc rockwell jlo engine in an attex and went to turn it over today for the first time since i bought it and i think my points are stuck closed. reason being is that when i turn the key on i have power to the engine and can touch the engine anywhere and the test light will light up. i have power going into the crank and then two wires coming out to the coil packs which both have power. from there, there is two wires one from each coil pack that also have power which ground to the motor. if i'm correct the points are suppose to open therefore causeing these two wires to ground out and create spark to my spark plugs. what does everyone think?

reason i ran across this is because when i turn the key over the solenoid just clicks and so i started tracing wires and the wire from the starter to the solenoid is hot with the key on due to the motor being hot and the wire from my starter terminal on my key switch to the solenoid is only hot when i turn the key to the start position.

Nate

[Don]

Hey, Nate;

Try running a ground strap from the engine to the frame. Let us know how it goes.

[nate52]

i started looking again and noticed that i didn't have the engine grounded so i hooked up a ground wire to the engine bracket and it turned over great, but i started to get a little smoke coming from out behind the flywheel. so i'm going to pull the flywheel tomorrow and get a new points plate and go from there. thanks for the reply, i'll probably need more advice here in the next couple of days cause i'm bound to run into another snap along the way lol.

Thanks
Nate

[6X6]

i started looking again and noticed that i didn't have the engine grounded so i hooked up a ground wire to the engine bracket and it turned over great, but i started to get a little smoke coming from out behind the flywheel. so i'm going to pull the flywheel tomorrow and get a new points plate and go from there. thanks for the reply, i'll probably need more advice here in the next couple of days cause i'm bound to run into another snap along the way lol.

Thanks
Nate

!!! If you're getting smoke, check your wiring. If the wiring was messed with, you could smoke a Charge or ignition coil. Points stuck closed should not make smoke. Also could be the regulator/rectifier. (Small grey box with fins) Make sure the yellow motor wires go to the ~ (A/C) side, and green wires to the D/C side. If it's backwards, the battery will cook the Regulator and charge coil. Here's the diagram.

[nate52]

if you haven't checked out my before pictures of this machine you probably don't realize how bad off this thing was when i bought it lol. i've gone with new everything from bearings to axles, and this also includes an all new wiring harness in which i made based on the exact schematic in which you posted. i could be wrong, it happens alot and the wiring may be wrong. i have all the wiring hooking up to the motor correctly according to the schematic, the only place i think i may have had a chance to go wrong is with the ignition switch and thats because it's a four terminal switch instead of a 5 terminal in which i used because i wanted the accessory option. the 4 terminals consist of ign, batt., starter, and accessory.

i have the two wires coming out of the five prone ( which run to the motor) that go to the ignition switch hooked to the ign. terminal which has power when the key is on.

a wire running from the battery to the rectifier and then to batt. terminal on the key switch.

a wire from the starter terminal to the small terminal on the solenoid.

and then my lights to my accessory terminal which arn't hooked up at the moment.

the only thing that has me guessing is that their is a jumper wire running from terminals 53 on the rectifier on the wiring schematic and it looks to be factory done. i don't know if it was or if the previous owner did this?

as for the smoke it looked to be internal beings it came from the right side of the motor (opposite side of the clutch) and it came from behind the flywheel and out of the fan with the black cover. but only after cranking it over probably 5 or 6 full strokes. cranked it over 5 or 6 full strokes stopped and then a couple seconds later the smoke and then i disconnected the battery.

all advice appreciated and sorry in advance for the length of the post.

thanks
nate52

p.s. if this is hard to understand i can draw up the exact way i have it wired and take a picture and post it for you.

[nate52]

thought it'd be easier for you guys to understand me if i provided an exact wiring diagram of how i have it wired right now. so i took the schematic into paint and color coded the wires i have now to my ignition switch and also the jumper wire they had for the rectifier. this is how it is wired exactly, so hopefully you can tell me if it looks ok or not?

[mark m.]

For starters it looks like your schematic shows the output of the rectifier is shorted

[nate52]

when i re-wired it i left that jumper wire on the rectifier because it was wired like that when i bought it, didn't know if it was suppose to be like that or not so i just left it the way it was. do i need to change that jumper wire and if so where to?

[mark m.]

Nate, I am not positive as to the type of rectifier your system uses but typically you have two wires (yellow AC) as an input coming from your charge coils under your flywheel. The output of that rectifier (other 2 teminals) is DC voltage. One is positive and the other is ground.

Having said that, on a Briggs rectifier/regulater there are only 3 wires and sometimes a fourth wire. Two wires (yellow) and one red wire (positive). The outside case is the ground so it has to be attached to the engine ground.

[6X6]

Nate and Mark The jumper on the Rectifier IS correct. That puzzled me, too, untill Don (site name) informed me that was indeed how they were wired. Both outputs ( #53) are Positive. The inputs, #51 with the A/C symbol ~ between them get the yellow wires. If you had the yellow wires and Hot lead to ignition mixed up, it would fry something. Now I'm reading your post again, and did it smoke while you were cranking it over? Or was it smoking after it was hooked up? I'm thinking maybe I read it wrong, and the starter motor was the smoker? If so you need to check that the motor turns over freely (Except compression) Starter motor isn't binding, Good connections on hot and ground side, and could be dirty/worn commutator, shorted comm or windings, or hanging brush (Though that normally results in no cranking power with smoke, or nothing at all)

[nate52]

from my plug i have wires 2 and 3 both running to terminals 51 on the rectifier. i have wires 4 and 5 both running to my ign. terminal on my ignition switch (of ign., batt., acc., and starter). i have my power wire running from battery to terminal 53 on the rectifier and then to my batt. terminal on my ignition switch, along with the jumper wire between terminals 53. when i turn the key on without cranking it over wire 5 (from terminal 51 on rectifier to ign. terminal on ignition switch) gets hott to the touch along with my power wire from the battery and i get smoke from behind the flywheel. wire 4 though doesn't get hot. it also smokes when i crank it over and i have no idea what i'm doing wrong. Please HELP!!!

[nate52]

after looking over the wiring diagram again for my engine i have come to the conclusion that it is wired properly since everything matches up with the diagram but i still get smoke when power is given to the cyl. ll wire which has led me to believe that this wire is shorting out. i believe it's internally shorted somewhere since i've checked my external wire and all appears ok and the smoke comes out from behind the flywheel. how do i get to the cyl. ll wire in the motor, can i access it through the pulling of the head or do i need to pull the flywheel? or is there another way i could be able to access this wire and do you think this could be the problem?

nate

[jpswift1]

Nate, I think you need to pull the flywheel to get to it. I'd imagine that it is shorting where there are moving parts or where there is a small opening where a group of wires are running through. The vibration probably caused the wire insulation to wear off over the years. Let us know what you find. I know these problems can be very frustrating......I've been there too. Good luck with it.

[KrS14]

I've had to research this schematic back when we first got the 400, so maybe a little clearing up of things is needed

The two wires labeled: Black Cyl I and II are grounds for the Blue and Blue-Yellow Pickup coils. These two wires need to be grounded to STOP the engine. So when the key is turned to OFF these two wires should be connected to a grounded terminal on your key switch.

Wires 2 and 3, the two yellow wires from the engine, have to SEPARATELY go a terminal on the rectifier, one wire for one 51 the other wire for the other 51.

Make sure you have #1 in the key switch harness grounded.

I can take a pic of our wiring on our 400 next time i'm at Dezi's if you'd like

This may help as well:

http://www.asberry.net/files/TwoStrokeSM.pdf

It helped me out.

[nate52]

so do my two black wires for cyl. l and ll get constant power when the switch on is in the on position?