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Discussion Starter #1
I picked up a $100 bike off ebay. '86 VN750 with 20K. I had intended to use her as a parts bike, maybe take a few things off her to augment Bess right away, and save the rest just in case I had some kind of failure.

The parts bike is kind of a mess, but as I look at her more closely, I think she has promise.

The main problems:

The gas tank is full of rust.
The bleeder bolts were snapped off on both brakes.
Someone stopped mid Ear Shave (the carbs are there, but no box or ears - also no replacement post-shave filters, or, as far as I can tell, any rejetting.)

Also, the radiator was removed, but is in a box. It looks like everything is there.

So. If the engine is good, it seems that some time and not a ton of money (thanks to ebay) might get her running again.

I can do all the work, I think. (I'm good mechanically, and figure things out, but have never done engine work before.)

Is there any way to make sure the engine's not locked up before I sink a lot of time into her? If so, how do I do that?

Where do you suggest I begin?
 

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The Professor
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I picked up a $100 bike off ebay. '86 VN750 with 20K. I had intended to use her as a parts bike, maybe take a few things off her to augment Bess right away, and save the rest just in case I had some kind of failure.

The parts bike is kind of a mess, but as I look at her more closely, I think she has promise.

The main problems:

The gas tank is full of rust.
The bleeder bolts were snapped off on both brakes.
Someone stopped mid Ear Shave (the carbs are there, but no box or ears - also no replacement post-shave filters, or, as far as I can tell, any rejetting.)

Also, the radiator was removed, but is in a box. It looks like everything is there.

So. If the engine is good, it seems that some time and not a ton of money (thanks to ebay) might get her running again.

I can do all the work, I think. (I'm good mechanically, and figure things out, but have never done engine work before.)

Is there any way to make sure the engine's not locked up before I sink a lot of time into her? If so, how do I do that?

Where do you suggest I begin?

Remove the left cover with the three screws and tirn over with a 17mm socket. Remove plugs first. :beerchug:
 

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The Reanimater
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Sit it on it's stand so the rear wheel is off the ground, make sure it is out of gear,
Hook a battery to the starter and see of it turns the engine over. (- to the case, + to the lug on the starter)
 

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The Reanimater
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Counter-Clock Wise ???????

Remove the left cover with the three screws and tirn over with a 17mm socket. Remove plugs first. :beerchug:
 

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The Professor
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Turn counterclockwise. :beerchug:
 

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Discussion Starter #6
Thanks guys.

I think the plan is - drain oil, pull cover and plugs, turn over, put everything back, fill with oil, hook up the starter to my battery and cross my fingers.

I'll let you know how it goes.
 

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if the bike has been sitting for a long time, before you try to turn it over you might want to squrt a little oil or trans fluid in the cylinders first , just in case.
good luck .it would be grate to seeone recyled and put back on the road insted of being scraped
 

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Discussion Starter #8
Thanks - it would really be the forum's credit as a whole I think. You guys have increased my technical knowledge about 20X. One of the reasons I love these bikes is that they're so predictable - when you have one you know what to look for and what to fix.
 

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Simple Solutions
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i got got stock jets air box and ears... the ears are a little scratched up but i got them hit me up i'll let it all go cheap
 

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Simple Solutions
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and for the rust in the tank us ph plus water and a car battery charger i spent 4 days with this methode and as long as the tank doesnt leak then there is no lining and the tank becomes rust resistant... there is a thread on here for exact details but its the easiest most effective way and there is no harsh chemicals to deal with...
 

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Discussion Starter #11
Seebeeare - thanks man. I appreciate it, but I think I'm going to slap some air filters on the carbs and try to finish the ear shave for two reasons:

1) it'll be a cool learning experience
2) i'm actually missing everything north of the carbs. (no boots/box/hoses/epa/ears.)

***
When I drained the oil it looked like snot. Not a good sign. But the guy I got it from said he was starting the engine on starter fluid. So maybe some of that got into the oil or something. I also found some eggs in the toolbox. They were tiny, about little fingernail size. Maybe snake eggs?

***

I tried to follow lance's suggestion, but I stripped a screw on my first twist. Doh! I thought it was turning since the resistance was the same as the other two that came out.

So I'm soaking it in PT Blaster and will be trying the file/flathead method. If that does not work, I will pick up a screw extractor kit from Harbor Freight.

Instead of going that route, is there a way that I can see if the rings are free by running the bike downhill? I'm pretty sure there is, but don't know what to do.

Miami is pretty flat, but I have a ramp up to a second story parking garrage in my building. How would I go about doing it? (step by step would be appreciated.)
 

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Discussion Starter #12
BTW, while I'm cleaning the tank, I'd wanted to at least be able to (hopefully) warm up the engine to help with oil draining/flushing. Is there something I can rig up with the Prime hose? Should I use the hose to funnel some gas into the carbs and just let the bike run through that to warm up? Or could I make a mini-tank somehow?

I'm pretty excited about this bike. I just don't want to fall into the trap of putting in work (say on the tank) and then finding out the engine's somehow screwed.

***

I forgot to say the plugs looked good, one a bit rich, but nothing alarming. Also, there were a few tiny aluminum shavings in the filter screen. Again, nothing too alarming.
 

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Simple Solutions
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Seebeeare - thanks man. I appreciate it, but I think I'm going to slap some air filters on the carbs and try to finish the ear shave for two reasons:

1) it'll be a cool learning experience
2) i'm actually missing everything north of the carbs. (no boots/box/hoses/epa/ears.)

***
When I drained the oil it looked like snot. Not a good sign. But the guy I got it from said he was starting the engine on starter fluid. So maybe some of that got into the oil or something. I also found some eggs in the toolbox. They were tiny, about little fingernail size. Maybe snake eggs?

***

I tried to follow lance's suggestion, but I stripped a screw on my first twist. Doh! I thought it was turning since the resistance was the same as the other two that came out.

So I'm soaking it in PT Blaster and will be trying the file/flathead method. If that does not work, I will pick up a screw extractor kit from Harbor Freight.

Instead of going that route, is there a way that I can see if the rings are free by running the bike downhill? I'm pretty sure there is, but don't know what to do.

Miami is pretty flat, but I have a ramp up to a second story parking garrage in my building. How would I go about doing it? (step by step would be appreciated.)
get an impact screw driver it will be a life saver for those hard to turn screws depending how deep u tear into this bike there will be more times u will need it
snake eggs neat...
ear shave beside loss of fuel milage its a great addition and looks great it also makes it eaisier to get in there without the air box....

in addition with that missin in your bike it makes be believe the engine has been takin out.. ....
for the rings being free u could remove the plugs pit her in gear and roll her down the hill however id wait till u got that screw out and do it manually...
 

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Discussion Starter #14
Update: I put my old non-MF battery on the parts bike. Right now I have no spark.

I need to do a more systematic trip through the starting circuit to see if I can figure out what's wrong. I checked kind of randomly, thinking it might be the engine kill switch, the ignition switch (under the key), the starter button, the main engine grounds, the fusebox, (all cleaned) and I actually have juice making it to the coils. Overall the harness looks pretty good. I tested the stator resistance and the RR and they checked out OK. The also coils tested good, but absolutely nothing happens when I push the starter button. There's no noise or anything - the bike just sits there like the key wasn't even in it. I feel like I'm missing something obvious.

I think the front coil grounds to the tach (or so someone said). I took the tach off, then tried it with the tach on. Either way though, something should be happening with the rear coil, right?

When i jump the starter motor, it whirrs and turns the engine over, albeit sluggishly. When I press the button, nothing.

Any thoughts on this, as always, would be appreciated.

***

Also - seperate issue: my petcock is frozen in the reserve position. I took it off the bike. To clean it, can I drop the whole thing in a glass jar with some seafoam and gas? I figured that wouldn't hurt the components.
 

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Simple Solutions
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Great news... engine turns

now im not sure on this but when i jump start the old scoot if i connect to the wrong side of the starter cylinoid (in essence connecting to the starter) it just turns and doestnt fire... if i had to guess on your situation its gonna be one of the safty switches
kickstand, clutch neutral, or kill swtch or ignition switch not neccisarily in that order

do u have lights when the bike is turned on?
 

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Discussion Starter #16
Yep, lights.

I checked various bits with a test light and most of the stuff lit up - all the fuses, the accessory leads, etc. Not very scientific, but I thought doing so would let me know if something major was shorting out somewhere.

I got light going to and from the ignition switch, kill switch and start button.

I checked out the kickstand switch. I unplugged it at the connector and tested the bottom half (with switch) for continuity - when I pull the plunger on the switch out, it gives me a circuit, when I push the plunger in, no circuit (I may be reversing that, but the reading did change). So I don't think it's the switch.

I don't know about the neutral switch so much. I know the bike's in neutral because the green neutral finder light is on. Is there a physical switch somewhere that I have to check?

I jumped the starter with a cable from the positive battery terminal to the connection on the starter. Is there a way to jump the coils as well?

Sigh. I was just hoping to find something on the first go around. I just need to spend more time with this. Although I'd much rather be doing physical restoration work than poking about with a couple of probes.
 

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Simple Solutions
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u can connect a positive lead to the red tabs on the coils there is a diagram here somewhere showing the rewiring of these coils with a relay connected to the kill switch... your on the right track the neutral switch is located on the back of the engine and should have a green wire attaced (your neutral light on is telling me that switch is working) hmm let me ponder a bit

Warning conecting constant power to the coils will drain the batt so unplug when not in use or diagnosing
 

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Discussion Starter #18
Hmm. Mabye a loose ground somewhere? I sat down with the bike again last night and just can't seem to find anything wrong.

Sheesh.

I don't have to have the headlamp connected for the bike to turn over, do I?

I think the next step for me is to do a side by side, point by point test with Bess. I know she works.
 

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Discussion Starter #19
Spark!!!!

From here on out it's just work. And lots of chemicals.
 

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Linkmeister Supreme
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Keep on, keepin` on. You`ll have her running in no time. Electrical bugaboos are my biggest hate, when trying to diagnose automotive problems. You will have a greater feeling of accomplishment and confidence when you do get her fired up.
 
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