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Discussion Starter · #1 ·
Well as some of you know. I have had some cooling issues with my low mileage 79 CX. After finally getting it sorted out I had cooling problems and received a lot of help from everyone here. So here is what I have done and the results. I took the thermostat housing out and took it apart. Even though the bike has 3100 miles it sat for 25 years. Inside was really corroded and the water inlet for the heads was crystalized. After sourcing a new thermostat, I put the housing back together with new o-rings. I flushed the radiator while the bike was running for ten minutes. I filled the radiator up with water and white vinegar 50/50. I then rode the bike to dinner with my wife and the bike never quite got to the red. We rode for about an hour after dinner and it only hit the red when we were riding really slow for quite a while. Out on the open road, it stays away from the red but is still a bit hotter than I would like. I am going to drain the water and vinegar tomorrow and fill it with Engine Ice and Water Wetter. I hope this will solve my cooling problems. Now, what say you on this?
 

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Well as some of you know. I have had some cooling issues with my low mileage 79 CX. After finally getting it sorted out I had cooling problems and received a lot of help from everyone here. So here is what I have done and the results. I took the thermostat housing out and took it apart. Even though the bike has 3100 miles it sat for 25 years. Inside was really corroded and the water inlet for the heads was crystalized. After sourcing a new thermostat, I put the housing back together with new o-rings. I flushed the radiator while the bike was running for ten minutes. I filled the radiator up with water and white vinegar 50/50. I then rode the bike to dinner with my wife and the bike never quite got to the red. We rode for about an hour after dinner and it only hit the red when we were riding really slow for quite a while. Out on the open road, it stays away from the red but is still a bit hotter than I would like. I am going to drain the water and vinegar tomorrow and fill it with Engine Ice and Water Wetter. I hope this will solve my cooling problems. Now, what say you on this?


I bet you have more crystallized coolant hiding in your system. I wonder if there is an easy way to remove it without having to scrape it out. One of my friends Tom had a mid mileage cx that sat for a long time and he said he spent 3 hours scraping crap out of the heads. But he's a perfectionist.
 

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Discussion Starter · #3 ·
I took my Dremel and cleaned as much as I could and then flushed the heads. I was shocked at how bad it was. Sitting for years is really hard on a bike. Also, this is my first ride on a CX500 and just seems a little under powered two up at 290 lbs. I have to down shift going up some of the hills when riding slow. Do I need to do more work on this thing? Carbs are rebuilt and only 3k miles. oh yea, the tach is useless.
 

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i think you diluted the vinegar too much,thereby reducing its ability to clean.

id fill the system up with 100% vinegar,warm the engine up,leave overnight,and drain.i think you will be surprised over how much more crap that will come out
 

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i think you diluted the vinegar too much,thereby reducing its ability to clean.

id fill the system up with 100% vinegar,warm the engine up,leave overnight,and drain.i think you will be surprised over how much more crap that will come out




Ditto and don't run the bike warm for any length of time.Use full 100% white vinegar and also with the rad off shove a hoe pipe into the coolant transfer pipe for 10 mins to flush around the engine.Did you soak clean and flush the Rad in White vinegar as well?



Have you also checked the 7v regulator to make sure the Temp gauge is reading correctly?



Click here,

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=257



Is the thermostat housing grounding corectly?
 

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I did as Bandit and Shep advised. A lot of white goo flushed out. A few cheap bottles of vinegar, your time, and patience will pay off.
 

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I took my Dremel and cleaned as much as I could and then flushed the heads. I was shocked at how bad it was. Sitting for years is really hard on a bike. Also, this is my first ride on a CX500 and just seems a little under powered two up at 290 lbs. I have to down shift going up some of the hills when riding slow. Do I need to do more work on this thing? Carbs are rebuilt and only 3k miles. oh yea, the tach is useless.
I can't say it's power is right or not, but these engines are high rev type that make a good amount of their power above 6000.  Peak torque is around 7500 and peak HP is near redline, around 8500 or so.  I guess that's not much use to you, I just realized you said your tach is no good.
 

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Discussion Starter · #10 ·
I can't say it's power is right or not, but these engines are high rev type that make a good amount of their power above 6000.  Peak torque is around 7500 and peak HP is near redline, around 8500 or so.  I guess that's not much use to you, I just realized you said your tach is no good.
Ok I will follow up this weekend. I am letting the 50/50 solution sit until Friday and then I will clean the transfer pipe as well. My carbs were rebuilt by myself and Blue Fox. I am a pretty good mechanice and know my way around them pretty well. I think I will fill up the radiator with just vinegar Friday afternoon and drain Saturday morning. The amount of crud in there is amazing. I would love to fix my tach but I am not sure what to do. It is slow to rev up and down and well it's just slow.
 

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Ok I will follow up this weekend. I am letting the 50/50 solution sit until Friday and then I will clean the transfer pipe as well. My carbs were rebuilt by myself and Blue Fox. I am a pretty good mechanice and know my way around them pretty well. I think I will fill up the radiator with just vinegar Friday afternoon and drain Saturday morning. The amount of crud in there is amazing. I would love to fix my tach but I am not sure what to do. It is slow to rev up and down and well it's just slow.
good luck,just make sure you operate the machine until the tranfer pipe gets hot,and the thermostat is open.then kill it
 
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