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Maybe I missed it but have you checked the voltage output from the stator? I ended up changing my stator out due to similar problems with the battery. Leaving the headlight on while idling, the output voltage from the stator would gradually drop to well below what it should be. Also check the regulator? The smoke? Not sure.
 

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Discussion Starter · #3 ·
Maybe I missed it but have you checked the voltage output from the stator? I ended up changing my stator out due to similar problems with the battery. Leaving the headlight on while idling, the output voltage from the stator would gradually drop to well below what it should be. Also check the regulator? The smoke? Not sure.
Have NOT checked the stator or regulator. I'll look up how to do that after work and see what's going on. I hope it's not the stator.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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Unless the radiator was sitting open, there's no way it would be clogged internally by a cloud of drywall dust. If it's clogged externally, that's easily corrected using compressed air.
Have you determined whether the PO wired the headlight off the Ignitech, as he was proposing? That would be high on my suspect list.
If you resolve to scrap the current wiring, you might consider looking for a clean stock harness. That could eliminate a lot of errors.
 

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'84 CX650E that is evolving into a GL500
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What they said ^^^

Also, neither of these will have anything to do with the smoke but
1) There are no purple wires in Honda wiring harnesses. That wire is brown, not purple. Believe it or not, it is connected to the tail light circuit and is there to power a parking light (small bulb in the headlight in places like the UK where parking lights are required).
According to the wiring drawing for your bike the horn is supposed to be connected to a black wire (in Honda wiring, black wires are switched power = live only when the key is on and protected only by the main fuse).
2) Why would you use Dexcool? The correct coolant for these engines is ordinary inexpensive glycol based coolant.

Re the smoke: Is it smoke or steam?
You can find out by holding a piece of white paper close to the end of the muffler: If the paper becomes wet it is steam, if it becomes oily it is oil vapour and if it becomes sooty it is smoke.
If it isn't wet and the coolant level in the coolant recovery tank behind the engine doesn't drop over time the problem is not a leak between the combustion chamber and the cooling jacket.
If it is oily it could be a leak between the combustion chamber and an oil passage or gallery.
If it is smoke the problem may be somewhere other than the head, such as a carburetion or ignition problem (others with more experience will hopefully clarify this).

BTW: Welcome to the forum. Please add your location to your profile and your bike's model and model year to your signature so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and the Previous Owners may or may not have done the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. Check the date codes on your tires and replace them if they are over 5 years old no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet). If your bike still has the original rubber brake line(s) (should be replaced every 2 or 3 fluid changes = 5 or 6 years) I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid). And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).
 

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Discussion Starter · #6 · (Edited)
What they said ^^^

1) There are no purple wires in Honda wiring harnesses. That wire is brown, not purple. Believe it or not, it is connected to the tail light circuit and is there to power a parking light (small bulb in the headlight in places like the UK where parking lights are required).
According to the wiring drawing for your bike the horn is supposed to be connected to a black wire (in Honda wiring, black wires are switched power = live only when the key is on and protected only by the main fuse).
2) Why would you use Dexcool? The correct coolant for these engines is ordinary inexpensive glycol based coolant.

Re the smoke: Is it smoke or steam?
You can find out by holding a piece of white paper close to the end of the muffler: If the paper becomes wet it is steam, if it becomes oily it is oil vapour and if it becomes sooty it is smoke.
If it isn't wet and the coolant level in the coolant recovery tank behind the engine doesn't drop over time the problem is not a leak between the combustion chamber and the cooling jacket.
If it is oily it could be a leak between the combustion chamber and an oil passage or gallery.
If it is smoke the problem may be somewhere other than the head, such as a carburetion or ignition problem (others with more experience will hopefully clarify this).

BTW: Welcome to the forum. Please add your location to your profile and your bike's model and model year to your signature so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and the Previous Owners may or may not have done the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. Check the date codes on your tires and replace them if they are over 5 years old no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet). If your bike still has the original rubber brake line(s) (should be replaced every 2 or 3 fluid changes = 5 or 6 years) I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid). And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).
Ahhhh, the infamous Sidecar Bob! Thank you so much. I feel like I already know you from lurking on here. A pleasure to connect!

1. On second look, it's totally a brown wire! Grime and weird garage lighting can really play tricks on the color.
2. I actually had dexcool on hand and had seen it recommended by a few people. Easy swap though, if that'll be a problem. I just drained it and filled it with distilled water anyways (to see if there's be a change in the stuff coming out of the pipe) .

Re the smoke:
I can't tell. It smells like exhaust and gets my eyes watering when it builds up in the garage for sure. I tried the paper trick (while the radiator was full of water) and the paper didn't get wet or oily or sooty. It didn't smoke for long with water at all, and the smoke seemed lighter when it was there. I'm going to try it again tomorrow with some regular glycol-based coolant and repeat the paper test.

I snagged a video of the radiator (filled with distilled water) while the engine was at 190 degrees F:
I can't tell, is that water moving like it should be, or is that movement simply due to engine vibration? The pipe going to the water pump was hot, but the engine temp kept climbing.
 

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Discussion Starter · #7 ·
Unless the radiator was sitting open, there's no way it would be clogged internally by a cloud of drywall dust. If it's clogged externally, that's easily corrected using compressed air.
Have you determined whether the PO wired the headlight off the Ignitech, as he was proposing? That would be high on my suspect list.
If you resolve to scrap the current wiring, you might consider looking for a clean stock harness. That could eliminate a lot of errors.
I haven't figured that out yet but I'll check it out in the morning. Where should it be wired to when an ignitech is installed?
 

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Discussion Starter · #8 · (Edited)
Maybe I missed it but have you checked the voltage output from the stator? I ended up changing my stator out due to similar problems with the battery. Leaving the headlight on while idling, the output voltage from the stator would gradually drop to well below what it should be. Also check the regulator? The smoke? Not sure.
I just tried doing this following the motofaction instructions. Everything looks good.

The numbers I got off the 7 prong harness where:

1/5: 115.5 - Correct
2/5: 93.2 - Correct
3/5 0.L - Faulty, but not needed with ignitech
4/5 113.2 - Correct
6/5 95.4 - Correct
7/5 42.4 - Faulty, but not needed with ignitech

I couldn't find a wire connector with three yellow wires or a wire connector with a blue and a white, so I stopped there. Still need to check the regulator rectifier. Will do tomorrow. Gotta look up that process.
 

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Discussion Starter · #9 · (Edited)
Smoke issue
Did a compression check on both sides and got 150 psi on each side. Noticed both spark plugs were oily when I pulled them.

I wonder if I just need to retorque the head mounts? I heard if oil gets in the threads, they can give a false number when tightening them up. I'll check that out tomorrow when I remove everything to check the water pump (regarding the overheating issue).

Cooling Issue
What are some tell-tale signs of a broken water pump? Would the impeller just be loose? It doesn't look like the fluids are moving around like they should, so I suppose this is what I should look at next? Below's a video of it running at 190ish F. Should I be worried about those specs of whatever floating around in there?

 

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Discussion Starter · #10 ·
What they said ^^^

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and the Previous Owners may or may not have done the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. Check the date codes on your tires and replace them if they are over 5 years old no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet). If your bike still has the original rubber brake line(s) (should be replaced every 2 or 3 fluid changes = 5 or 6 years) I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid). And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).
Such stellar advice. I just swapped the brake lines on my 4runner for stainless and it was a breeze. Once I get my other's issue fixed, that'll be at the top of my list along with checking all the other rubber parts.
 

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It's just that you are a new member and some of your posts have links or attachments that upset the forums security settings for spam.

Your posts go into an approval queue and I approve them when I see them so there is a delay depending on whether I am near the computer or not.

I would have thought this would have stopped by now but should soon.
 

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re #12 though cumbersome....might be something good in being cautious as other CX forums were "killed by spam"🗿

no offence to the OP
 

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We nearly were before verticalscope took over. Literally hundreds a day.

A few still turn up in the approval queue but they don't get in.

Forum software catches most first.
 

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Discussion Starter · #15 ·
It's just that you are a new member and some of your posts have links or attachments that upset the forums security settings for spam.

Your posts go into an approval queue and I approve them when I see them so there is a delay depending on whether I am near the computer or not.

I would have thought this would have stopped by now but should soon.
Ahhh, gotcha!
 

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I'm glad to see you working your way through all the bugs. We'll get ya sorted sooner or later. Keep at it, man.
 

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'84 CX650E that is evolving into a GL500
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Cooling Issue
What are some tell-tale signs of a broken water pump? Would the impeller just be loose? It doesn't look like the fluids are moving around like they should, so I suppose this is what I should look at next? Below's a video of it running at 190ish F. Should I be worried about those specs of whatever floating around in there?
I wouldn't be unduly concerned about those specks (coolant passages tend to be pretty wide) but they aren't doing any good either so if you haven't already done so this would be a good time to service the cooling system
'

The easiest way to tell if the water pump is working is to feel the radiator. The top of it will get hot when the thermostat has opened and if the pump is working the bottom of the rad will become warm quickly after that (you can also tell by feeling the water pipe on the engine's left side but it won't get hot until hot coolant is flowing out of the bottom of the rad).


The water pump consists of an impeller attached to the rear end of the camshaft running inside a shaped cover bolted onto the rear engine cover. If the impeller is loose it generally means that the nut that holds it on was not done up to the specified torque and has loosened or that one of the washers was left out when it was last assembled. In either case I would expect to see coolant escaping through the weep hole and running down the side of the engine near your left foot.
It is possible for the weep hole to become blocked, whether by a PO who thought he was "fixing" a leak (these guys never read the FSM) or by an insect looking for a home, in which case the coolant would accumulate in the space between the camshaft oil seal and the water pump mechanical seal and could get past the oil seal and into the crankcase (this is why the weep hole is there)
 

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Discussion Starter · #18 ·
Okay, I've got (once the engine hits about 170):
  • Nothing coming out of the water pump's weep hole.
  • Hot pipe on the engine's left side that leads to the waterpump
  • What appears to be no visible flow of liquid in the radiator (aside from it jostling around from the vibration of the motor) - am I wrong here? Is the liquid in the video moving as it should?
  • White smoke coming out the right exhaust (may not be related).
  • Engine overheats and the radiator liquid boils if left going for about 20-30 minutes
So my best bet is to:
  • Check for weephole blockage (seems like the smoking pipe could be from that causing the coolant to get into the oil, but wouldn't that cause both sides to smoke?)
  • If weep hole was blocked, clear it and retest the system
  • If weep hole isn't blocked, get the radiator serviced for possible blockage or replace the radiator (which is the better solution there)?
Questions
  • Is the above a good order of operations? Anything I'm missing?
  • Am I good to just use distilled water in the radiator while I'm testing all this stuff?
  • Should I be checking the hose that goes from the waterpump to the thermostat for blockage? Is that a possibility?
  • For the smoking pipe, I'm going to pull everything apart to retorque the head mount bolts. Anything I should give an eye to while everything's apart?
    • If that doesn't fix the smoke issue, would the next logical thing to do be to resurface the head?
    • It looks like one side has a rocker assembly from a 650, could that be an issue?
 

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I've never seen coolant flowing in a rad by looking into the filler with the engine running either.

As I said before, a leak between the combustion chamber and the cooling jacket will result in steam in the exhaust, not smoke. White smoke could be oil burning, possibly from the head gasket but after the gasket has been changed that many times I'd be looking for something like a bad valve guide seal.

I would expect the engine to overheat if left idling for half an hour (especially if the rad cap was off so the cooling system couldn't achieve the designed operating pressure). It was not designed to sit still that long. The fan can only pull so much air through the radiator and it really needs the bike to be moving most of the time to get enough air movement through the rad to cool the engine properly.

Checking that the weep hole is clear is never a bad idea but the main reason I mentioned it was to help you understand the water pump. I don't think a blocked weep hole could cause smoke from only one exhaust. It might be possible under extreme conditions for coolant that was forced past the oil seal into the crankcase to be expelled by the breather system, which is connected to the airbox so maybe if there was enough of it to be drawn into the carbs and thus into the engine it might possibly cause some steam but that's not terribly likely and it would be on both sides, not just one.

Water is OK for testing, just make sure you replace it with proper coolant before the temperature drops below freezing (don't just drain it because any water that remains can freeze, expand and damage something)(run the engine for a while to circulate the coolant and mix it with any remaining water too).

What I would do next is fill the rad all the way, put the cap on and ride it for a while. After a couple of short rides with time to fully cool after each the level in the coolant recovery tank should drop a bit as any air in the system is expelled to the tank and fluid is drawn back from the tank to replace it. After that keep an eye on the level in the tank and if it stays the same coolant is not getting into the combustion chamber (note that big bubbles in the tank are a sign that a head gasket is leaking).

If it is not related to the cooling system and is indeed smoke from burning oil that you are seeing, oil can enter the combustion chamber from a head gasket leak, a leaking valve guide, piston rings that aren't sealing well and probably a bunch of other sources I can't think of but I'm sure others will add to the list.
 
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