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1980 cx500c
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Discussion Starter · #1 ·
Just bought a 1980 cx500. It turned over but didn’t start, first thing I checked was the plug wires and sure enough they were torn off preventing any spark. I couldn’t find any direct replacement coils/wires so I got some suzuki drz ones that were recommended in an old thread. They look almost identical I’m just having trouble figuring out how disconnect the bracket or whatever it is from the old coils so I can put the new ones on. Can anyone help with that?

Other thing was I checked the oil and it seemed to have coolant in it. Not too surprised as the guy I bought it from had it sitting for a loooooong time. I’m seeing a lot of “mechanical seal” but I also saw that if it sits a while it’ll happen naturally and that if I run it for a bit it’ll seal back up. If I put new oil in it and ran a couple hundred miles do y’all think that might help?
Don’t know too much about it as I just got it and I’m busy with work but according the seller it ran fine, I checked all the electrical and it all works except the taillight/blinkers that I still have to put on. Was also told it shifts okay. I want to put these coils on so I can start it and see if these things are true. Any pointers?

Thanks for reading!!
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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12,105 Posts
Welcome!
First, download the Factory Service Manual. Many members have the link in their signatures.
Verify that the weep hole is clear under the chrome water pipe at left rear of the engine. A leak at the mechanical seal only reaches the crankcase of that exit path is blocked.
Fresh oil, top off the coolant, and run it for a bit. Watch for coolant below the weep hole. If it stops on its own, you're good. If not, replace the seal.
 

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1980 cx500c
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16 Posts
Discussion Starter · #4 ·
Welcome!
First, download the Factory Service Manual. Many members have the link in their signatures.
Verify that the weep hole is clear under the chrome water pipe at left rear of the engine. A leak at the mechanical seal only reaches the crankcase of that exit path is blocked.
Fresh oil, top off the coolant, and run it for a bit. Watch for coolant below the weep hole. If it stops on its own, you're good. If not, replace the seal.
Thanks Randall! I’ll look for that manual and check for that leak when I get home. I’ll post if I find anything
 

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'84 CX650E that is evolving into a GL500
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18,431 Posts
Welcome to the forum. Please add your location and your bike's model and model year to your profile 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 may or may not have had all of the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual that Randall mentioned (the correct one for your model is 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).

Is it actually coolant in the oil or just a bit of water from condensation?

As Randall said, coolant from a failed mechanical seal won't get into the oil unless either the oil seal behind it is badly damaged or the weep hole is plugged. If it is actually coolant it is far more likely that a head gasket is blown (usually the oil looks like a chocolate milkshake).

BTW, "running when parked" is seller's code for "sort of ran, then wasn't stored properly and has been completely neglected since last used".
 

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1980 cx500c
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16 Posts
Discussion Starter · #6 ·
Welcome to the forum. Please add your location and your bike's model and model year to your profile 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 may or may not have had all of the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual that Randall mentioned (the correct one for your model is 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).

Is it actually coolant in the oil or just a bit of water from condensation?

As Randall said, coolant from a failed mechanical seal won't get into the oil unless either the oil seal behind it is badly damaged or the weep hole is plugged. If it is actually coolant it is far more likely that a head gasket is blown (usually the oil looks like a chocolate milkshake).

BTW, "running when parked" is seller's code for "sort of ran, then wasn't stored properly and has been completely neglected since last used".
Thank you, when I took out the dipstick, the oil looked fairly new but it looked to have milk in it. Took it out again later and it seemed fine. Never owned an old bike like this so I agree with what you’ve said. I’ll have to go over it thoroughly although I’m not the best with bikes so I don’t know how it all works and what it should look like. I will get that manual asap, is it free? Also the seller told me he bought it a couple years ago and rode it around and whatnot, (starting to doubt he actually had it running good), then had it sit for a long time because he got other projects and lost interest in this one. For right now I’m trying to get it to run good as all my buddies want me to ride with them again. So I’ll have to look for that leak and see if I can find how to swap out the coil in that manual.
thanks
 

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'84 CX650E that is evolving into a GL500
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If the milkiness went away it was probably just condensation, but I'd keep an eye on the oil and the coolant for a while to make sure.
The manual is free to download.

The manual won't have anything about changing to a non-original coil. I'm not familiar with the ones you mentioned but it isn't uncommon for things like that to require making a bracket to attach them in place of the originals (usually steel strip from the hardware store cut to length with a couple of holes drilled in it).
 

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1980 cx500c
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16 Posts
Discussion Starter · #8 ·
If the milkiness went away it was probably just condensation, but I'd keep an eye on the oil and the coolant for a while to make sure.
The manual is free to download.

The manual won't have anything about changing to a non-original coil. I'm not familiar with the ones you mentioned but it isn't uncommon for things like that to require making a bracket to attach them in place of the originals (usually steel strip from the hardware store cut to length with a couple of holes drilled in it).
Okay, I got the manual and if it helps I could send a couple pictures of the current coils and the new ones
 

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'84 CX650E that is evolving into a GL500
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Those orange coils aren't the original ones. Here is the best pic of original CX500 coils I could find but at least it shows how they are mounted to the frame (seen from above)


You said the coil wires were "were torn off preventing any spark". Can you ple4ase explain what you mean by that? The wires seem to be attached to the orange coil in your pic...

I had never seen those orange coils before today but while I was looking for pics of the original ones I came across the pic below. Apparently they are Emgo coils and should work on your CX. The fellow who posted that pic couldn't figure out why he had no spark with them and it turned out all he needed to do was tighten the bolts so that the coils were grounded properly
 

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1980 cx500c
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16 Posts
Discussion Starter · #12 ·
Those orange coils aren't the original ones. Here is the best pic of original CX500 coils I could find but at least it shows how they are mounted to the frame (seen from above)
Ohhhhh so those two bracket things are just to bolt it up, I thought they were part of the coil, maybe I’m just dumb. I guess my best bet would be to go find a couple long bolts
 

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1980 cx500c
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Discussion Starter · #14 ·
Have another look at my last post. I clicked the Post button too soon and you read it while I was editing it to add the second part.
Yes so what I meant was the plug caps came off the wire, so I guess there isn’t a proper connection from the wire to the plug.
sorry if I’m not explaining good, been a long day at work
 

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If you look at the plug cap where the wire had been attached you will see what looks like a screw. That screws into the end of the plug wire. Try cuttin about a 1/2" from the end of the plug wire and then screw on the cap.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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My current coils (for most of a decade, I think) are similar to your replacements. They're shorter than stock. I never did get around to making the brackets for the loose ends.
 

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1980 cx500c
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Discussion Starter · #19 ·
If you look at the plug cap where the wire had been attached you will see what looks like a screw. That screws into the end of the plug wire. Try cuttin about a 1/2" from the end of the plug wire and then screw on the cap.
So yes I saw that, been trying to screw it on for the last 5 minutes and it doesn’t seem to wanna go in
 
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