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Discussion Starter · #1 ·
I recently took a 1990 VN1500 out a friends garage with 4500 miles on it. It hadn't been ridden in at least 3 years. I cleaned the gas tank and drained the float bowls and got it started. The problem is when I drained the coolant only mud came out. Any ideas on how to get a good cleanout of all the coolant passages.

Thanks,
Rich
 

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A couple things that you can do. On light duty to med crud you can use white vinegar and distilled water. Dump your coolant (properly dispose of course) and fill with 50/50 soloution and run your bike. Costco $5.00

You can try good ole radiator flush and do it a couple of times if it is bad. If it looks like days old coffee and is muddy and you do not see rapid improvement done by yourself I would hand it over to a pro. $7.00 a flush.

I found crud in my radiator overflow bottle and I took mine to a radiator shop and had the radiator rodded out. Meaning that the radiator was completely and professionally cleaned out with pressure, chemicals and refurbed 100%. $30.00
 

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Discussion Starter · #3 ·
I removed the thermostat and found one of the upper cylinder hoses completely plugged with what seemed to be dried up anti-freeze and minerals (like sand). I then removed the cylinder drain screws and flushed with a garden hose from the now disconnected upper cylinder hoses until water came out freely and cleaned everything I could get to. I reassembled and flushed with Prestone Radiator flush. I then put the 50/50 mix of prestone and distilled water.

Now when it runs after around 15 minutes at idle I get violent bubbling at the reservoir.
 

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You're doing great. Flushing is about the best you can do. You may still have some junk in there, but as long as the bike runs cool enough for you, I wouldn't worry about it.

That bubbling is because there is air in the system. You probably didn't fill up the radiator all the way when you refilled it. Or maybe you dumped out a hose and left it empty. In any case, the reason you got violent bubbling is because you had a lot of air in the system. When that air expands, it bubbles into the reservoir tank. When you park the bike, it will suck some coolant back into the radiator as the air bubble in the radiator cools off. There are two things you can do to fix the problem:
1. When the radiator is cold, take off the cap and fill it all the way to the tippy top. You will still have a little tiny bit of air in there, but not much. Then run the bike to let that air work out.
2. Ignore it. This is what I would recommend. You've already bubbled out a lot of the air that was in there. As long as you keep the reservoir full, in time the air bubble will be gone. It won't take very long -- maybe two or three heat/cool cycles, unless the bubble is huge. If the bubble is that big, you'd notice that the bike is running hot. You've probably already done one or two of those cycles, so you're practically done.
Curt
 

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Top off you coolant and find your coolant valve by the bottom of your pipes and bleed the line to get rid of the air. Open it up until you get liquid coming out and close it again. Fill up the resevoir to appropriate amount and fire her up!
 

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also, good job with using distilled water. tap water has all kinds of crud in it that will form scales inside the engine block and radiator, making them lose their efficiency and eventually clogging things.

if you ever get a leak, never ever use the "stop leak", or "alumaseal" or whatever they call it now, the powdered metal sealer in a plastic tube. i've seen many many radiators permanently clogged and destroyed water pumps from that stuff. have the leak fixed properly.

sorry, a little off topic, just a little advice.
 

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Discussion Starter · #7 ·
I've tried to bleed the air out according to the manual with the bleed valve near the radiator cap, but can't seem to get a constant stream of coolant like they say. How could someone tell if the coolant was boiling, like I thought, or if it's just air? I'm going for a couple short rides today. Need to get out and ride a little .....

Thanks,
Rich
 

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bear09 said:
I've tried to bleed the air out according to the manual with the bleed valve near the radiator cap, but can't seem to get a constant stream of coolant like they say. How could someone tell if the coolant was boiling, like I thought, or if it's just air?
if you have coolant in the system and its sealed/not leaking then its not BOILING (like 212deg. water boiling) its just air passing thru the system. you may need to flush this system time after time till you get the passages cleaned out. the next time you do it, use one of the coolant system cleaners that all the auto parts stores have. you could just run distilled water w/ cleaner so that your not wasting anti-freeze. may need t replace your rad. cap also. it may not be holding pressure in the system which WILL make your coolant boil.
are you pouring the water slowly and letting it sit till it drops down ? tap all the rad. hoses as you fill ,that will help break up/displace the bubbles and get them to come to the filler cap. its really not wise to ride with an air pocket in the system.
good luck
 
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