Blown coolant hose thermostat to r/h upper engine.

[Liamray]

Was warming up my ST1100 yesterday and went inside to grab my jacket, when I came back out there was coolant running out on the ground and a huge cloud of steam coming from the bike.
I shut it down straight away and waited till it cooled down to check what had happened. And when I checked the overflow reservoir it was still full and the fluid was cold, weird I thought, so when I finally got to the radiator cap and thermostat I found that the overflow tube from the radiator cap to the overflow reservoir was blocked solid with gunk. After I pulled the air cleaner and carbs off I discovered that the hose from the thermostat to the r/h side of the engine was blown, and when I say blown I mean blown (see Pic). Would the fact that the overflow tube was blocked have caused the hose to blow i.e. the pressure couldn't escape back down to the overflow?
After checking everything out I also noticed that because of the steam it seems that the carby coupler rubbers have hardened like rock, so I guess I'll be replacing those as well.
What I wanted to know is there anything else I should check that may have been affected by this incident?
The bike is a 2001 ST1100 with 87K's on the clock. Any help or information would be appreciated.

[alans1100]

Check and replace any suspect hoses and best to both the hoses that go under the carbs. While you're in there check the elbows that hoses connect to. Not so bad on ours but earlier models tended to crack.


Radiator cap and thermostat I'd do as well. Thermostat housing could crack if it got to hot so a clean up that as well and check it out
The carby rubbers tend to harden with age and heat from the motor and it's easier to reinstall the carbs if you put new ones in.

With the gunk already mentioned it would pay to flush the radiator as a precaution.

[Liamray]

  Thanks for the info Alan, yeah I've flushed the system and it seems to be pretty clean? The blockage in the overflow was strange, it wasn't a hard material, it was flexible but still hard to remove (had to drill it out). Would this blockage have contributed to the hose blowing out? As I said would the blockage have prevented the system from venting an excess pressure? I pulled the thermostat out and cleaned it up and it looks to be okay, I'm yet to clean up the area under the carbs, and when I do I will have a good look at the elbows and replace them if necessary. The carb rubbers will be replaced, saw them online in the USA for $35 for the 4, don't know what they are here, will check with the Honda dealer, but from experience local price is usually 3x online price.

[alans1100]

It's possible the blocked hose contributed to that hose blowing but it could very well have had nothing to do with it as it gets quite hot in there. Not much airflow through there either.

Here's the hoses under the carbs on my 1100 at 150,000 km - one was close to bursting and now I would advise replacing them every 100,000 km http://ozstoc.com/index.php?topic=2977.msg34375#msg34375

I guess if the reserve tank hose was blocked it wouldn't allow the coolant to flow into the tank as it got hot; something has to give in the system and it's generally the weakest point.

[Liamray]

  Thanks Alan all good info, I'm tempted to do the timing belt while I have the bike stripped down, but it's only done 87k's so I'm not sure whether I'd be just wasting my time at this stage. I think I will follow your lead with the thermostat and radiator cap though, better to do it now than have to strip the bike down to do it in the near future. I've seen a set of hoses advertised online 'Blue Silicon Hoses with Clamps' for $84, ever heard of them or know of anyone that's used them?

[alans1100]

By all means inspect the belt which would normally be due to done at 100,000.

Just remove the plastic covers in front of the cam covers and the timing hole cover. You need to remove that so a socket can be used to turn the motor (remove plugs) and only turn in a clockwise direction.

[Bikebear]

I've bought a complete set of coolant hoses, vacuum lines, carby rubbers, head stem bearings and a timing belt to give my '99 an 18th birthday. I have a couple of weeks off coming up so the bike will be in the shed getting a rebuild and general clean up before I head off on the SCA poker run in September.

[Liamray]

  Thanks for the replies and info.
Finally got the beasty back together and running, everything seems to be okay, cleaned and checked the thermostat and cleaned all of the elbows and pipes, and everything is as it should be. Hope to take her for a good long run to make sure there are no more surprises!

[Sicman]