I know it's been asked before, but wasn't able to find the threads. I have a coolant hose that looks at this point to have a clamp that is not tight enough. Repaired a portion of the issue having a split in the overflow tube at the thermostat housing and the upper rubber gasket on the rad. cap had several splits. After resolving that problem thought the issue was taken care of. After riding two days in a row, did not have a leak that I could see and there was no longer a couple drips on the man-cave floor. Now, after 2 days of not riding it decided to drip a couple drops of coolant on the floor. Dripped about where the center-stand is. So, this time I pulled necessary tupperware off and removed the fuel tank so as to maybe follow the drip. After looking from the backside of motor with a flashlite, the leak looks to be initiated at the lower left-side hose clamp. Is there a trick to access these lower hose clamps without removing carb assembly? Thanks in advance for any and ALL advice.
ST 1100 coolant hoses
- Thread starter Brant
- Start date
I know some have been able to tighten all of those screw clamps without pulling the carbs... I do seem to remember that they didn't think it was a *fun* chore...
However: I would recommend getting a loaner radiator testing kit from an autozone or Checker auto and finding the leak source rather than; tightening the clamp, putting the bike back together and then finding you still have a leak...
The leak on the '93 was a split aluminum elbow.
The one on the left as you look into the valley from the back; but, I ordered both for replacement. Glad I did too as the right elbow split into 2 pieces as I was removing it for replacement.
However: I would recommend getting a loaner radiator testing kit from an autozone or Checker auto and finding the leak source rather than; tightening the clamp, putting the bike back together and then finding you still have a leak...
The leak on the '93 was a split aluminum elbow.
The one on the left as you look into the valley from the back; but, I ordered both for replacement. Glad I did too as the right elbow split into 2 pieces as I was removing it for replacement.
STranger
Jay Knight
Got a good peek under there from the rear with tank removed. Since being in dry climate and having no corrosion issues, the underside in that area is clean and shiney. Impressive for being a 92' , but fairly low mileage at 77,000mi. Once I saw exactly where to look on both sides, got a clear view of the area, hoses and clamps. Looks to be fairly easy to get too once I go and purchase a long 6mm open end/box-end wrench. Gonna go with the hose clamp lightly tightened a bit without squishing into rubber for now. Upper connections at thermostat housing all good, so see what happens from the results. The tank was but a few minutes to remove, so not an issue in the future. If I still have an annoying coolant drip after sitting, sounds like an easy enough chore to replace the hoses during the colder months when not riding. Will post back as to the success until colder months if needin' to just replace those hoses. BTW, thanks for all the quick responses!
You should replace those hoses, they are 19 years old, and you never know when they are going to fail you. I replaced mine and though not leaking they felt brittle compared to the new ones. Just a thought.
John OoSTerhuis
Life Is Good!
Brant,
Mark gives good advice about borrowing a pressure tester to confirm the actual leak source. But to cinch the hose clamps, there's a link to my pictures w/captions at the end of Mike Martin's webpage that may help... here it is:
http://community.webshots.com/album/56797755XfYwTD
a 6mm open-end miget/ignition wrench on an extension will get you to the undercarb cylinder banks' hose clamps:
HTH
Regards, John
Mark gives good advice about borrowing a pressure tester to confirm the actual leak source. But to cinch the hose clamps, there's a link to my pictures w/captions at the end of Mike Martin's webpage that may help... here it is:
http://community.webshots.com/album/56797755XfYwTD
a 6mm open-end miget/ignition wrench on an extension will get you to the undercarb cylinder banks' hose clamps:
HTH
Regards, John
Thanks John! Was able to get a long boxed on both ends 6mm/8mm from sears. Lookin up in there, head upside down is a bit tedious.
Got the upper and lower hose connections tightened. The bike itself was the pressure test, dropping the tank back in and hooking up. Underside connections neeed a bit more tightening as they still were wet and green around hose end. Washed everthing clean again, dropped tank in and ran on center stand till fan came on........no leaks. Been riding the scoot for a couple days now and all seems to be good.....gauge stays consistantly bout 1/4 ways up and fan comes on when temp hits bout halfway in town traffic. Jury still out as to this being the fix in this case. Occassionally, when first starting up and after it runs a couple min, can detect a slight antifreeze smell, then it goes away bout as soon with no green stuff hittin' the ground. Guess it's very possible the smaller by-pass hose may have the same clamp issue. Also, not ever havin' the carb bank off one of these scoots, don't know if there is an actual place coolant can pool up, burnin' off as case heats up. Hosed it all good in under the rubber map and air-hose blew it dry under there, so who knows. Started it up to warm up this morning, and no antifreeze smell or drips.............so, time will tell. Again, thanks to those with the tips, Brant.
The real test will be your cold weather.
Ours only had *that* smell when cold weather had caused some different shrink rates between the rubber and the aluminum pieces.
Ours only had *that* smell when cold weather had caused some different shrink rates between the rubber and the aluminum pieces.
Good point Mark! I've been riding it for a few days now. So far after riding and it sets all nite, there has been one drip of green hit the floor. Possible bypass leaking at a clamp point, but would think that would show at start-up with possible pressures being more until thermostat opening(just thinkin outloud). Other than that, temp gauge seems to show all working properly, with normal highway running in the 1/4 range. Now, this afternoon, after running up in the mountains(Grand Mesa) and hitting the Interstate, temp gauge hit past the halfway mark AFTER exiting the Interstate coming to a stop at a signal. Figured that was bout normal as I had just rolled it.......let's just say a good ways into three digits for a bit. Ambient ouside temps were in the mid 70's. At this point, and no LD rides this time of year, just gonna keep watch on it. May get one of those boring days and a bit too cold to ride and just decide to pull the carb bank and replace those hoses and look it all over while there for a peace of mind. Already have a lenght of the Super- Sil hose to do it, just will have to get a couple of the fancy "smooth" clamps as I think the worm slots of the common screw type clamp will bite into the outer casing of this type hose. For the most part, these type of repairs seem harder with just the idea of having to do it. Once jumping in and just doing it, there not all that bad, just a bit time consuming at worst. 
Gotta go with you on that. I developed a love/hate relationship early on with my ST11. Love riding it, a little less than thrilled about working on it. Not so much because of the work but because of the ritual of pulling the tupperware off. Thats what holds me up as much as anything sometimes - just the thought of pulling the plastic off has caused a certain amount of procrastination at times. Its not that hard, but for some reason for me having to pull it off is some sort of deterrent. And as you pointed out, once you actually start performing the task that needs to be done its not so bad. Actually, I rather enjoy that part.
I think you have a good idea to wait for some CO cold down time and then pull it apart for line replacement.
I would also use the rubber dam as a pattern and make a replacement out of ABS shower mat (home improvement store in the DIY bath section) and you might consider having the carb to engine rubber connectors handy... I didn't know I needed to replace them and I too am loath to pull the carbs off just for that job...
Tupperware is funny... I don't like pulling it; however the last time I did it Chris said she was surprised at how little time it took me to get it all off and the gas tank out. I guess with 3 ST110s I have *way* too many opportunities to practice!
I would also use the rubber dam as a pattern and make a replacement out of ABS shower mat (home improvement store in the DIY bath section) and you might consider having the carb to engine rubber connectors handy... I didn't know I needed to replace them and I too am loath to pull the carbs off just for that job...
Tupperware is funny... I don't like pulling it; however the last time I did it Chris said she was surprised at how little time it took me to get it all off and the gas tank out. I guess with 3 ST110s I have *way* too many opportunities to practice!
Thanks Mark! I'll look them over good. Boot looked to be in good shape when I stretched it a bit up over the carb boot clamp so I could see to get to that left side clamp. What I could see of the carb boots, they looked fine. BTW, some good ridin' weather bout now where your at. Son and daughter in-law live in Tucson and he rides a 91VFR to his college classes. BTW, glad to see I'm not the only one that procrastinates. Lots I haven't worked on with the ST, but since it's all mechanically related, at times I feel that I sure don't need the practice. Although there is some interesting concepts conceived on this motor design and the twin-spar frame wrapped around it that are a bit curious..........at times.