Another guy with a coolant leak

With all the cowel sections removed (to source a horn problem) and after a good cleaning, I noticed that the coolant bottle was empty.
I topped it up and ran the engine for a few minutes. The leak seems to be at one of the bolts holes.
See the image below.



I removed the bolt and plugged the hole but the leak continued.
Has anyone seen this before?

My bet is the coolant leak is from the "V" area from the hoses below the throttle body, my question is where did that bolt for the cover go?

And now a coolant leak

Well I found the problem with the horn.
While all the fairing components were removed I took the opportunity to give the engine a good cleaning. Done.
I noticed that the coolant reservoir was empty. I topped it up and ran the engine for a few minutes.
Drip, drip drip.
I think that the coolant is leaking from the thermostat cover.



I can see fluid were the arrow is indicating above. It runs down and drips from the bottom of the case.
The DPO mentioned that the thermostat had been replaced.
How ugly a job will it be to replace the gasket and probably the thermostat as well (while I'm there)?
Cheers.

Re: And now a coolant leak

I removed that bolt. I didn't notice the water flowing from above that point.

Re: And now a coolant leak

What is the "V" area?

The space between the two banks of cylinders is the "vee". There the collective cooling system hoses are found and any seeps or leaks have a well defined path down hill that drains out alongside the front water pump cover.

Easy is relative to one's skill but I would say compared to other tasks replacing the thermostat O ring is an easy one.

Send me here or in a PM your email address and I'll send you a tutorial on replacing the thermostat. It's simple to follow step by step with pictures. You may not replace the T-stat but the O ring is right there.

The red arrow looks like the typical hose leak.
The thermostat is up further. That o-ring is a pretty easy swap.
Could be the water pump housing gasket. Easy fix pita to keep the o-ring seated while putting the cover on and engaging the water pump spline. If anything oil would seep out of that bolt hole. Likely coolant ran down the case and wicked into the hole from the front. Likely it's running down the slot between the water pump cover and clutch cover.

See blrfl's fixing the coolant leak for good thread with the breeze constant tension clamps as long as the plastic is off.

That fluid looks awfully clear, did you by chance recently wash the bike?

Water pump cover gaskets don't leak. Caveat.......... I guess anything is possible but after umpteen thousand coolant system leak threads umpteen thousand owners find the hoses and/or the thermostat housing O-ring behind the radiator in the vee seep or leak. The coolant runs down the drain channel which is between the water pump cover and the clutch cover. If you look directly from the right side you will see a square hole where the drain channel exits between those two covers. Coolant runs down the right front of the engine between the two covers. Some may run directly down the front cover ( the clutch cover ) but most of it exits the square drain hole.

Clamps. A gentle snug of the clamps at valve checks or other services keeps the leaks at bay. Changing out the clamps works but it wasn't necessary for me to take care of this. Snugged at 86,000 miles, snugged at 116,000, snugged at 145,000. Snugging is not wailing down on the OEM worm screw clamps, it's a turn or two.

Hot tip on that "did you wash the bike"! Yes I sure did.
The drip has slowed for now. If it's just water I will be a very happy Mr. Fixit.
The bike was on the driveway, on center stand during the wash.
It was then wheeled to its repair station. I blew as much water off as I could.
It then stood for 24hr. All I did today is top off the coolant tank and start run the engine for a few minutes.
I'll check the puddle and run the engine again.
Thanks.

Beware the sample size of 1 LOL.
The half moon section of my water pump housing was compromised.
Agreed not typical.

Croz that really does look like water. Hopefully that's it.
If the covers are still off and you don't see any evidence on the hoses I'd still snug the clamps while you're there take a look at the bottom hose of the reservoir you might have a a cracked hose dumping a little or it's just been ages since you filled it. Another sample size of 1, my reservoir developed a 1" long crack a little bit down from the fill neck. Didn't look like it was leaking but it got the crazy glue baking soda treatment while I was in there. You may well have just chased some wash water around and had it drain back.

I removed the air cleaner chamber and had a peek underneath. Not a lot of access to hose ends. I tightened all that I could get at.
I buttoned it back up and ran the engine until the fans kicked in. No leak.
Just a few more parts and I'll be able to refit all the panels. I may get a ride in before the snow starts!
Lots of smoke here from the forest fires.
Thanks for the help.

If you come in from the front by removing the radiator all the hoses except for the ones on the oil cooler are accessible. Something to do next time.

dduelin said:

If you come in from the front by removing the radiator all the hoses except for the ones on the oil cooler are accessible. Something to do next time.

Click to expand...

Dduelin, thank you for sharing all the wonderful expertise on the ST1300. Can you send me your info on removing the radiator to get at the thermostat? I am in the midst of trying to tighten the clamps to stop the coolent leak.The plastic is off right now. I dont see a way to drop the radiator without draining it first. That is more challenging than I want to tackle right now. I am going to put the plastic back on and study up your information first for the next time. We are still riding around here. May be in Januray, I'll deal with it again.
Thank you in advance.
kennylocke987@yahoo.ca

Sure but I'm at FLSTOC now and for the weekend. I'll send it to you next week.

You might PM me a reminder.

DD, no problems, next week is fine. I appreciate it. I buttoned the bike up already. Deal with it another day. Enjoy FLSTOC.

ST460 said:

DD, no problems, next week is fine. I appreciate it. I buttoned the bike up already. Deal with it another day. Enjoy FLSTOC.

Click to expand...

I have forwarded copies of what Dave kindly sent me last spring when I had the job to do.

Keith, got it. Looks very comprehensive. I'll studying carefully before attempting it. Last time I remove the radiator, I put a hole in it and had to buy a new one. Thanks.
Kenny

ST460 said:

Dduelin, thank you for sharing all the wonderful expertise on the ST1300. Can you send me your info on removing the radiator to get at the thermostat? I am in the midst of trying to tighten the clamps to stop the coolent leak.The plastic is off right now. I dont see a way to drop the radiator without draining it first. That is more challenging than I want to tackle right now. I am going to put the plastic back on and study up your information first for the next time. We are still riding around here. May be in Januray, I'll deal with it again.
Thank you in advance.
kennylocke987@yahoo.ca

Click to expand...

No way to remove the radiator without draining it first, but it isn't rocket science to do that, very easy as long as you're careful enough to recover most of the drained coolant with minimum spillage to have to clean up. There was an excellent article here several years ago on how to flush/change coolant on the ST1300, but I can't find it now. I saved the pdf file way back then, but I haven't been able (yet) to figure out how to attach it to a response to your post. If I can figure out how to do it, I can reply again with the attachment, but if you're mechanically inclined it shouldn't be that difficult for you, just be prepared to set aside a few hours to do it right.

I think I got it:

does the water in the reservoir have to be replenished frequently or is there an overflow tube from the radiator that goes back to the reservoir.

etalors said:

does the water in the reservoir have to be replenished frequently or is there an overflow tube from the radiator that goes back to the reservoir.

Click to expand...

First question: No, unless there is a leak somewhere. Second question: Yes