Hey guys how's it goin! So I don't actually have a 1985 FJ1100 motorcycle unfortunately but I do have a crazy mini sand rail thing with a 1985 FJ1100 motor in it and I bought it non running sitting for two year and I have replaced the battery Cdi fuel pump fuel filter cleaned the carbs bought new ignition coils and everything is super darn crazy close to being functional but. I can't seem to get a spark. No fuses are blown and power is going in and out of the ignition coils but alas still no spark... Makes me so sad and I'm frustrated and ran out of ideas of what to check or do or replace any hep would be grand! See pictures down below!
Here's a better picture of the motor also if anyone has a picture of the wiring diagram I would just love to have it
Also! Just found the old video the guy gave me when it was running.
https://youtu.be/8OQXyEaWfhs
Enjoy
http://www.fjowners.com/index.php?topic=2146.msg16944#msg16944 (http://www.fjowners.com/index.php?topic=2146.msg16944#msg16944)
This should give you the wiring diagram used by legends cars.
What are you using for coils? I haven't seen anything like that pictures before - looks like an old aftermarket VW coil but with two leads?
Yeah the coils I'm using just have a similar ohms rating and have the same one wire in one wire out and two spark plugs sparking at the same time configuration it's the cheapest aftermarket ones I can find haha it's kind of a budget build. here are the coils. in the middle are the stock coils on the FJ I believes. I left them there just in case they weren't bad and it was some annoying wiring issue
Coils
sounds like this will be a full-blown diagnostic work out...
So, to get things started - when was the last time it has run? What has been done to it since it last ran?
For the basics to work from -- CLEAN THE CARBS (it may be a spark issue, but dirty carbs will give you more grief than you can imagine) and MAKE SURE THE BATTERY IS GOOD (charge it overnight and go have it tested - new or newish doesn't automatically mean its good...)
All you need to know about these carbs is here: http://www.fjowners.com/index.php?topic=655.0 (http://www.fjowners.com/index.php?topic=655.0) and a ton more info here: http://www.fjowners.com/index.php?board=21.0 (http://www.fjowners.com/index.php?board=21.0)
As far as wiring -- been there done that a few times now with scratch built and re-built harnesses. If you are not absolutely sure about the work previously done on the wiring, you MAY be better off starting from scratch. I NEVER recommend that to someone working on a bike with a mostly original harness, but in the case of the car, it may be better.
Well, it looks like a lot of the previously posted wiring diagrams are broken links now - here's another: http://www.fjowners.com/index.php?topic=10574.msg102883#msg102883 (http://www.fjowners.com/index.php?topic=10574.msg102883#msg102883)
I know some people will say a solder connection is best, but I prefer crimp connections - less skill required (although I'm getting better!) and preferred by many for high vibration applications (airplanes, motorcycles, etc).
Having created my own share of electrical issues with the harnesses I made (and lost lots of time and events and money lost) - I'd advise using ox gard on all crimp connections and use heat shrink crimp terminals. Get a good set of crimpers (don't have to be ratchet style if you are on a budget) and be sure to pull-test each crimp before heat shinking.
(http://fjowners.com/gallery/10/171_29_06_16_8_59_06.jpeg)
Ox gard can be found at radio shack, ace hardware, and possible lowes/home depot. It is dielectric grease with zinc added - improves conductivity and helps prevent corrosion in the future. But DON'T use it on multi-pin connections or anywhere else where the connectivity of the grease could cause a short.
(http://fjowners.com/gallery/10/171_29_06_16_9_01_23.jpeg)
Heat shrink terminals are available at most car parts places. NAPA seems to be VERY high priced for them, Harbor Freight the lowest price for them, most other car parts places somewhere in the middle. They aren't cheap, but they are a lot less expensive than towing the buggy somewhere and then loosing the whole day/weekend because of electrical problems.
If you prefer to work with what you have, start at the battery and work your way out using the legend car diagram above. You can also use the troubleshooting procedures in the GYSM found here: http://www.fjowners.com/index.php?topic=15432.0 (http://www.fjowners.com/index.php?topic=15432.0)
Good luck and keep us updated with the progress and results
Quote from: fj1289 on June 29, 2016, 10:38:25 AM
I know some people will say a solder connection is best, but I prefer crimp connections - less skill required (although I'm getting better!) and preferred by many for high vibration applications (airplanes, motorcycles, etc).
Yep, I agree with Chris. a *quality* mechanical crimp is best for high vibration environments.
The key I've found is investing is a quality ratcheting crimp tool. I've had this Titan Crimp tool for over 20 years now
(https://images-na.ssl-images-amazon.com/images/I/81kRSAqVQCL._SL1500_.jpg)
$26 on Amazon: https://www.amazon.com/Titan-Tools-11477-Ratcheting-Terminal/dp/B0069TRKJ0/ref=sr_1_1?s=hi&ie=UTF8&qid=1467226992&sr=1-1&keywords=wire+crimpers+tool (https://www.amazon.com/Titan-Tools-11477-Ratcheting-Terminal/dp/B0069TRKJ0/ref=sr_1_1?s=hi&ie=UTF8&qid=1467226992&sr=1-1&keywords=wire+crimpers+tool)
I love investing in good tools.
Damnit Pat! I've got enough things to spend money on already! Good price - I think I'll have to get one of those ...
Holy cow thank you so much! Those links you posted are mega mega mega helpful! I'm pretty sure the guy who built this used the original wiring harness so the wiring diagram is very helpful! haha there's still a turn signal and switch board fastened to one of the pipes haha the thing has been issued a legitimate Utah state vin and not one for off road use only so in reality I think I could throw some lights a windshield and some fenders on this death box and legally drive it on the streets! Hahaha it's got an extra tire to push however the ratios are smaller so I'm thinking the gearing on it should be pretty fun also it's a solid axle in the rear with absolutely no slip at all... Should be a drift monster to I will upload pics and such as they come! Thanks for the help so far!
You *will* need some airflow on that engine or it will cook itself. Look into what the Legends guys do...
It's basically completely open on the front. the aluminum fire wall is only between the driver and the motor but front and back of the motor are completely open
I was looking at the aluminum shield in front of your header tubes, blocking airflow to the top end.
So after thinking about it I think I may want to wire up my own wiring harness. But only for the spark if that's possible? im not sure where it gets the timing. And like I said it has power going in and out of the ignition coils so idk why it's not sparking. Does it just send more wattage or ohms or whatever down the wire to make it spark or what makes it actually spark?
Also I have already had the carbs torn apart and cleaned they were gunked really badly. Also the after market fuel pump I bought may be to much psi because whe. It starts pumping fuel a little bit of fuel starts leaking out of the drain tubes coming off the carbs SOO that's a little sketch I might just throw a fuel pressure regulator on the line somewhere and play with it and see if that makes it happy
Also it leaks a little bit of oil out of the clutch cover *see attached image* and I think it's cause like 4 bolts are stripped out. I bought a new gasket in hopes that would solve it but I think I'm gunna have to figure out how to drill out new threads or something
Read this and it will give some understanding of how and why it functions. https://en.wikipedia.org/wiki/Capacitor_discharge_ignition
So if I read that right in order for it to spark it's stops sending power to the coils therefore letting the energy that is built up to discharge and creating the spark?
Yes I believe so, I'm not a master in the theory but something has to tell the coils when to discharge. You have an ignition cover on the left side case, I'd suggest you remove that cover and have a look inside. I'll throw my two cents in now and tell you what I observed. The P/O of that rail ran the shit out of it, the bald rear tires and the video of him doing donuts was a tell tale. Not that I'm against having fun but the FJ engine requires air moving over it to cool it down (That s why Yamaha designed those FJ scoops to get air onto the inner cylinder heads) Sure the guy had an open area in front of the engine but when you spin in circles at 7000 RPM all day that becomes irrelevant really fast. Heat is the enemy of electronics, there are wires, glue, plastic, magnets and other things in that housing that are only designed take so much heat before they deteriorate ( A magnets main enemy is heat). Id investigate in there and pull some OHMS reading on that unit and make sure its within tolerance. When you get it going I'd suggest a strong fan with a shroud to cool those heads. When you see smoke bellowing up off the engine like I did after the donut session that's not a good sign for an air cooled engine. Front brakes would be nice too. Its a pretty cool little project, I can see why you want to get it going.
OK - since it sounds like you are using the Yamaha wiring harness, lets do a little troubleshooting on that first before jumping into the deep end and starting to rewire things.
Have a look starting at page 6-27 (pdf page 230) for the section on the ignition system. Obviously the placement of things on the sand rail will be different than on the bike, but you at least will know what you are looking for. Read thru the whole section on the ignition system before you start into it. Page 6-31 (pdf page 234) in the GYSM has the system description (after the troubleshooting section!) Then it shows how to check the various components.
With the setup you have, I really think you are going to be better off working with the stock harness - at least until you get things figured out. It won't matter how its wired up if you've got a bad component somewhere!