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Discussion Starter #1
So after putting my bike back together, I'm noticing a few leaks here and there. I figured since the bike is an 86, it can't hurt to replace the hoses. Another thing I'm noticing is its running really hot, so I might as well replace the thermostat, and cap while I'm at it. Does anyone know the sizes of the coolant hoses? The ones going to the cylinder heads, radiator to block, radiator to thermostat, and thermostat to filler neck?

I'm going to attempt to bend the coolant hoses myself, and see just how far I get with it. The main hoses leaking at the moment, are the thermostat to radiator, and back cylinder to thermostat. If anyone knows these sizes it'd be greatly appreciated.
 

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Captive New Yorker....
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when I put my engine back in, I had a few leaks in some hoses after running the engine for a while, even though I thought I tightened everything down, but it turned out that the clamps needed to be tightened even further. After that, no more leaks....
 

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Discussion Starter #3
That's what I figured also, but some of the hoses I didn't even touch, yet they're leaking. Overheating is becoming an issue as I live in Florida, and its getting hotter out now. So I can't really have any issues with my cooling system. I might need to alter my coolant mix for the weather, right now I'm running about 50/50. Turns out those o-rings for the 3 screws on the stator cover were junk. Bought brand new ones because everyone says to, one of em so far ripped.
 

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That's what I figured also, but some of the hoses I didn't even touch, yet they're leaking. Overheating is becoming an issue as I live in Florida, and its getting hotter out now. So I can't really have any issues with my cooling system. I might need to alter my coolant mix for the weather, right now I'm running about 50/50. Turns out those o-rings for the 3 screws on the stator cover were junk. Bought brand new ones because everyone says to, one of em so far ripped.
The 50/50 coolant mix is good for you year around in Florida. The coolant will give you a higher boiling point than pure water, as well as containing corrosion inhibitors.

If you have ruined/ripped one of the little O-rings sealing the screw heads on the stator cover, then get another, or it WILL leak around that screw.
 

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Sparky!!!
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an o-ring kit at HF is only 10 bucks.. the o-rings for the coolant hoses can be picked up at napa for under a buck each... RTV is not good
 

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The 50/50 coolant mix is good for you year around in Florida. The coolant will give you a higher boiling point than pure water, as well as containing corrosion inhibitors.
Wrong, a little higher water to mix ratio is better down south. Water transfers heat better. Antifreeze acts more of an insulator. Antifreeze does just that, not as much freezing there. Even a low percentage of mix will prevent corrosion. I would say 70water/30antifreeze would be good for you and even down to 80/20 would be max to me anyway~
 

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Unless there is something wrong with your cooling system, a 50/50 mix of distilled water and ethylene glycol will work fine, unless you are in a really cold climate, then I would use up to 70% ethylene glycol. Use only ethylene glycol, alcohol based coolants like DexCool will not work. They don't even work well in engines supposedly designed for them.

I live in AZ, where it is HOT (115 degrees average in the 7 month summer) and I use the 50/50 mix with no problems. If it still overheats, checked for a bad t-stat, plugged radiator, plugged coolant passages in the engine, or a bad water pump. Also check to see if the coolant fill cap is holding pressure.

It is not uncommon for engines that have has tap water in them to have everything plugged up. That stuff contains minerals and acids, and will start corrosion in an aluminum engine, and once it starts, corrosion just gets worse and worse.

I recommend the stock hoses. Yes they are expensive, but should last forever. Mine are 10 years old, and are still like new. You don't want to use a hose that might not be able to deal with the heat/pressure, or have a kink in it. OEM hoses are preformed to fit right.
 

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The standard recommendation is to use a 50/50 mix of antifreeze and water. This represents a compromise between cooling efficiency and the ability to prevent the mix from freezing during cold weather. After all, the initial purpose of antifreeze is to prevent freezing.

But a 50/50 mix does not give the best cooling. For improved cooling in hot weather, we should use less antifreeze and more water, perhaps going to a 25/75 or a 20/80 mix ratio.

Temperature drops ranging from 10 - 15 F are typically obtained by decreasing the mix from 50/50 down to 25/75 or perhaps 20/80. It is not possible to give precise numbers here because of uncertainty in knowing exactly what the initial mix was, and so forth.


Source

After a bit of net surfing I found that that others are saying lower ratio of anti freeze to water does improve the cooling. Just need the higher ratios for cold freezing weather.
 

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Sparky!!!
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in Afghanistan, we were using as little antifreeze as possible due to the extreme high temp. but unless you live in death valley, there is no need. 50/50 will be fine.
 

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Wrong, a little higher water to mix ratio is better down south. Water transfers heat better. Antifreeze acts more of an insulator. Antifreeze does just that, not as much freezing there. Even a low percentage of mix will prevent corrosion. I would say 70water/30antifreeze would be good for you and even down to 80/20 would be max to me anyway~
I`ll go along with water being a better heat conductor. I was referring to the standard recommendation to run a 50/50 mix. Maybe a 30% antifreeze concentration will give adequate corrosion protection in a hot climate. But if you look at the antifreeze jug it usually has a small chart giving the freezing and boiling point of different concentrations of mix. I don`t recall if I have seen any recommendation or figures for concentrations less than 50%, or higher than 70%. But all recommended concentrations have a boiling point higher than pure water. Perhaps a 25 to 30% mixture does have an even higher boiling by a few degrees, (shrug), I don`t know.

I do know the maximum recommendation I have seen for antifreeze protection is 70%. I have used a 70% concentration, but it was only necessary on cars with a propane fuel conversion in very cold weather. I will skip the explanation why this is so as it is not germain to the topic of the opening post.:)
 

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Water IS a better conductor of heat, but it also has a higher boiling point than a 50/50 mix of water and ethylene glycol. Modern cooling systems were not designed to run pure water for that reason (and for corrosion protection) If pure water is boiling, it is not going to cool your engine even if the temperature gauge shows ok. 50/50 is the best safe mix for almost all climates. 70% antifreeze will not cool as well, but if it is cold enough to need that much, it doesn't need to. I just use Maxima premixed motorcycle specific coolant and it works fine.
 

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Discussion Starter #13 (Edited)
an o-ring kit at HF is only 10 bucks.. the o-rings for the coolant hoses can be picked up at napa for under a buck each... RTV is not good
I think you misunderstood what I said. I already bought the 3 o-rings for the stator cover. I put them on, and noticed I was getting a tiny bit of oil running from em. I backed em out, and they were all chewed up for some reason, even though they were brand new.

As for the coolant hoses, I didn't mention anything about the o-rings for the coolant hoses(I assume your referring to the ones that go into the cylinder heads). I already replaced the one that was leaking, turns out I had a spare in a little bag, with my compression gauge.

I'll also mention its most likely my fault on the 3 o-rings, I just put them on the screws themselves. Rather than pushing em in the hole, so they got squeezed when I backed in the screws, which tore em up. If the RTV doesn't hold I'll just bite the bullet, and order 3 more.

Thanks for anyone who gave suggestions, I'm going to just replace the hose clamps as a few of them are worn out. That will most likely fix my problem, as I don't see any holes in the hoses themselves.

This has been a nightmare of a bike for me, my first cruiser and its ruined my opinion on them. Once I get it to a decent running condition, I'll ride it just long enough to get a bit of cash and then pick up another sport bike. Not quite sure why you guys like this bike so much, but to each his own.

P.S. Also just a little something I was wondering about. When removing the emissions crap, there's a hole left in the air box that is empty. Was I correct in pulling the plug, filling it with silicone, and popping it back in? Figured it'd be an air leak, but hadn't read anything about plugging it.
 

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P.S. Also just a little something I was wondering about. When removing the emissions crap, there's a hole left in the air box that is empty. Was I correct in pulling the plug, filling it with silicone, and popping it back in? Figured it'd be an air leak, but hadn't read anything about plugging it.
If you are referring to removing the air injection system, then yes the large hose from the air box to the valve would be removed and the hole in the air box should be plugged.
I chose to leave the hose in the airbox and just plug the hose near the rear of the battery box.
 

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This has been a nightmare of a bike for me, my first cruiser and its ruined my opinion on them. Once I get it to a decent running condition, I'll ride it just long enough to get a bit of cash and then pick up another sport bike. Not quite sure why you guys like this bike so much, but to each his own.
That's the key here. Cruisers are just like any other used bike or car, you really don't know just what shape they are really in when you buy them. I think that you will like the Vulcan once you get a few bugs worked out. Myself, I like my bike, don't like Goldwings, and not so much street bikes either. But it doesn't really matter what you ride, it's that you ride. :)
 
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