CHANGING THE ENGINE COOLANT

From: Charles E Rudd

The coolant system includes the radiator, an overflow tank molded to fit the 
top of the front two cylinders and a second overflow tank in front of the 
battery in the right fairing pocket. The normal fill point is the second 
overflow tank near the battery, you need to remove the 5 screws that let you 
get into the lower portion of the fairing to see this overflow. If you want 
to change out the coolant you should remove the left lower fairing, if you 
have this, so you can access the radiator cap. Open the radiator cap just 
part way, open the drain and empty the engine, radiator and overflow tanks. 
Then fill the radiator at the radiator cap adding 2 to 2.4 oz. of Barr's Stop 
Leak as you fill the radiator. Barr's Stop Leak is put in the system at the 
time of manufacture and is recommended for anytime the
coolant is changed. Close the radiator cap tightly, and fill the overflow to 
the cold level.

Key points to think about:

The radiator cap is pressure rated, so when cold, the cap is sealed and 
isolates the overflow tanks from the radiator. This is why you open the cap 
slightly when draining, you want the entire system to drain down.

The t-stat is the thermal-mechanical device that opens and allows 
circulation between the engine and the radiator. Just as in a car this is a 
wear item. My was found to be leaking since the seal had shrunk over time. 
I actually removed the side panels to remove the seat, to remove the center 
cowling, to remove the radio case that allowed me to access the t-stat from 
the top.

The overflow tank over the two front cylinders is subject to a lot of heat. 
This tank is about 2 inches in diameter, 10 inches long, comprised of two 
halves (lengthways) with 3 ports. Mine was cracked in several places along 
the 20 inches of seam. This meant I would lose any antifreeze that I put in 
to bring it up to the normal level, but the bike worked OK since it did not 
overheat when I test rode it before purchase. I took the tank out, cleaned 
it carefully, sealed the entire seam with JB Weld and then pressure tested 
it at 1.5 PSI. The two overflow tanks are above the radiator cap so they 
are only at atmospheric pressure, but I figure if it holds at some low 
pressure I would be more confident when putting all that stuff back 
together.

While working with this, I would check the terminals at the fan switch 
located near the radiator fill port. This is the switch that turns on the 
fan to pull air through the radiator, particularly when sitting and idling.

I am less sure about the temp sending unit, I believe it is located in the 
area of the t-stat, but I did not do anything with mine and the illustration 
in the service documentation is not really clear to me. There is a separate 
device for this function though and it's function is to send an electrical 
signal to the temp gauge in your display.

I agree with others who are recommending the use of the CD/ROM available 
from Cavalcade_USA Owner's Support Group. Tracy has done a great service to 
us all by making this available. I have printed the entire CD twice, one 
stays in the barn and one goes by my chair for evening reading. You would 
do well to get the CD
and walk through the checks that are spelled out very plainly in the manual.