Coolant and thermostat change

[Marcomalo]

I am getting ready to change the coolant and thermostat on my 03 1300. While I have the plastic off is there anything else I should change out or check at 50K miles?

 

[dduelin]

Remove the radiator and snug all the hose clamps around the thermostat housing and the inlet and outlet joins on the cylinder heads. At 50k there is likely some seepage or leaks. If not, you can prevent them in the next thousands of miles.

 

[John Anthony]

If you're still running with a stock horn, I'd replace it while you're at it.

John

 

[Don B]

If you haven't already done so recently, or per the maint schedule, it would be a good time to bleed/flush the brakes and check the valve clearances.

 

[Igofar]

When you have the radiator off, take a scotch brite pad and clean all the black paint off the spouts, both inside and outside, and flush your system out as well, you'll most likely find black paint in your T-stat housing as well.
Also, you may want to remove the hoses from the T-stat housing, and clean the corrosion off them too, so they seal well. Check the mystery plug (underneath T-stat housing) to make sure it's not leaking oil) while your there, Take some vinegar and a handful of nuts or BB's and clean the crud out of the overflow tank too. While you've got things apart, it would be a good time to changes the plugs, air filter, and do a TB sync if you have the correct tools, etc.

 

[jonjonboo]

best to remove the radiator to tighten all hose clamps---mud creek sounds interesting.

 

[Marcomalo]

I have all the plastic off and I have a factory service manual, but I cannot locate the thermostat housing. Anybody got a pic on where to find it?

 

[Mellow]

 

[Scooter]

I have all the plastic off and I have a factory service manual, but I cannot locate the thermostat housing. Anybody got a pic on where to find it?

You will see it once you remove the radiator...

 

[dduelin]

I have all the plastic off and I have a factory service manual, but I cannot locate the thermostat housing. Anybody got a pic on where to find it?

Remove the radiator and the cross member that connects the left and right frame down members. The T stat is behind that cross member in the Vee of the cylinders. You can follow the large radiator hose from the left side of the radiator to the T-stat housing as well. If you send me an email I'll send you a tutorial that is easy to use for this job. PM me.

 

[Marcomalo]

Sure thing. Will do and thanks, dude.

 

[Al Gully]

I was reading about the seized idle adjustment cable recently.
Not sure if your going to be adventurous and remove the throttle body.
If you do, I would do this or at least lube it if it is functioning:

https://www.st-owners.com/forums/showthread.php?133447-ST1300-Fixing-a-seized-Idle-adjustment-cable

 

[trm]

I just did the t-stat/coolant myself a couple of weeks back. If you have any issue getting off stuck hoses, I found a small squirt of PB Blaster will do the trick. Also, I ran a gallon of distilled water through the radiator until it came out clear. It solved my issue of bike not getting up to temp (3 bars).

And agree on bleeding the check valve, as well as all the calipers since the plastic is off. Otherwise, all I did was clean out all the dead butterflies and bees.

Tom on the N. Side of SA

 

[kendall]

Timely thread as I'm preparing to do coolant, hoses and t-stat on my '04 w/ 43k miles. I'm in southern Utah where we get summer temps in the 100's and sometimes dip into teens in winter. Last winter I got some small drips on startup, now this winter it's worse, but still just an annoyance. I'm the 2nd owner and bought it with 30k miles and I'm sure everything is original on the bike. T-stat works fine so this is just timely maintenence work with an eye to stopping the infamous cold weather drip.

Where is the best online source for correct pen parts?
I have read various opinions on flushing. My gut tells me it's ok. Why would the motor cooling system be any different than a car system?
Thanks in advance for hints on where to buy parts.
Kendall

 

[Don B]

And agree on bleeding the check valve, as well as all the calipers since the plastic is off. Otherwise, all I did was clean out all the dead butterflies and bees.

Tom on the N. Side of SA

What is the check valve you're referring to?

 

[Marcomalo]

Does anybody have a recommendation on the coolant type and brand?

 

[ChucksKLRST]

I use the Honda automobile premix 50/50. It is the same stuff as the Motorcycle Honda coolant at half the price. About 22 bucks a gallon. I use to use Preston long lasting silicon free for years. Any quality Silicon Free for aluminum engines will work.

 

[Tom Mac 04a]

+1 on the Extended Life Prestone... silicate free, good for bike and last time I bought it for $11 a gallon ( unmixed ) on sale.

 

[Marcomalo]

This is a great resource site and I want to thank everybody who posted advice. I have finished the coolant and thermostat flush and change-out. The old thermostat still tested good, so I kept it for a spare. While I was at it I flushed the brakes and clutch. I don't think they had ever been flushed. The fluid looked cloudy and brown. Hard to say how long the coolant had been in, but I know it is fresh now.

The ST1300 is absolutely the finest piece of equipment I have ever owned and I have owned a bunch. It is not the fastest, but who cares? It is a beautifully engineered machine and I expect it will be the last one I ever own, assuming I don't wad it up.

Thanks again.

 

[acedantinne]

Hey, just to add a little over looked section of the coolant system.
There is 2 lines that are the lowest in the system. Yes, to the oil filter, cooler. U need to flush that OUT. U will be some what surprised what collects in that filter area.
Me thinking, lowest area=collection point.
I had 2 bad thermostats. Found most of debris there.
used compressed air to clear, lines & cooler. Flushed with clear water.