Coolant Leak right in the middle of my ST1100

Someone removed the heat pad on mine before i bought it last april. I just found out while doing a bunch of work on it now. so far it has run just fine with no vapor lock issues either.
 
My rubber mat has disintegrated long time ago, I’ve tossed it probably around 8yrs ago and has been running without it, I lived in south east Asia and ambient temp is around 24-34C, bike has about 70k km confirmed mileage, just fyi.
 
Winfried - if you go back to post #65 I used the photo you posted earlier and marked the area in yellow where your leak was. It appears the hose is bloated and has a small tear showing in the image. I also had a leak in this same spot.
 
Well, you were right. I forgot to connect the hose from the water Pipe. Took radiator and and Thermostat off. Bought new hose as I cracked the old stiff putting it on the thermostat housing. Now hoses connected, put water in, and it leaked at the thermostat housing. Turns out I lost the O-ring. It is Sunday, and Honda Parts is closed. So ordered it on Partzilla. Honda Parts probably didn't have it anyway for a 2002 ST1100.
 
I started this post regarding my fixing the leak, replacing the hoses in November 2022. Hoses replaced, watched the YouTube video, which did do a step by step. Just showed after removing and nothing about how to put back together.

Now I placed the insulators on after misplacing two of the clamps, so I had to order replacements from PartZilla costing $30 and taking 2 weeks to arrive. Should have gone to the Honda Dealership down the street. Now with the insulators connect to the bottom 4 intakes and ready to set the carbs onto the insulators, I connected 2 hoses, one big one in the front, and a small hose to a T connection. Now how do I get the carbs to seat onto the insulators? Struggling and everything I read and saw on the video, it seems its no big deal to take off the carbs and put them back on. Can't seem to get all 4 to seat properly. The insulators have the tops and bottoms with different shapes and cut outs. Nothing showed if the insulators put on in a particular position. Took pictures before removing, but can't tell from them how they are supposed to fit. HELP. Is there a way to put the carbs connected to the insulators.
 
Make sure the insulators are lubed with something suitable. I used Mission Automotive Silicone Paste. I actually use that stuff for a lot of things, and if you don't have a slippery surface, good luck. You could probably use spit, but don't use anything that will degrade the rubber.
The insulators have a ramped mouth, so just set one side in first, then push down firmly on the other side of the metal air box that surrounds the rubber air horns. It'll go in if everything is properly in place. There should be a noticeable pop as they seat, but you should also be able to see everything level. And put the clamps on before you seat the carbs or you'll have a tough time doing it after.
 
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I started this post regarding my fixing the leak, replacing the hoses in November 2022. Hoses replaced, watched the YouTube video, which did do a step by step. Just showed after removing and nothing about how to put back together.

Now I placed the insulators on after misplacing two of the clamps, so I had to order replacements from PartZilla costing $30 and taking 2 weeks to arrive. Should have gone to the Honda Dealership down the street. Now with the insulators connect to the bottom 4 intakes and ready to set the carbs onto the insulators, I connected 2 hoses, one big one in the front, and a small hose to a T connection. Now how do I get the carbs to seat onto the insulators? Struggling and everything I read and saw on the video, it seems its no big deal to take off the carbs and put them back on. Can't seem to get all 4 to seat properly. The insulators have the tops and bottoms with different shapes and cut outs. Nothing showed if the insulators put on in a particular position. Took pictures before removing, but can't tell from them how they are supposed to fit. HELP. Is there a way to put the carbs connected to the insulators.
For me, this is always been the most difficult part of reassembly when changing the hoses underneath the carburetors. I’ve done this a total of three times on two bikes (2 STs), once years ago, to take the carburetor bank off to clean the carbs and about five years ago to do the hose replacement on both of my STs. There is no specific way of telling you how to do this. It’s just that you can’t line up one bank on the right and then have it fit on the left. They all kind of have to go down together into the carburetor boots. I can tell you it is a bit of a pain but ultimately a little bit of lubricant goes along way. You can try silicone spray or silicone grease like Shin Etsu. Some will disagree but the only way mine went back on is with WD-40, which is anathema to some. I didn’t use a lot of it just enough to get the bottom of the carburetors to go into the boots. That was years ago and my bikes run absolutely fine.
 
yeah, when I did the coolant hose job the carbs were a mystery to me as to how to put them back into place. I tried over and over again and finally they just plopped down into the boots. I used silicon grease as was mentioned earlier, but its really a matter of getting them to align just right and they will fall into place. Just keep trying and I think eventually you will find the right angle to get them to seat.
 
I stood on the pegs and pushed the left side down then rocked the carbs side to side and the right side finally popped in. It wasn’t much of a pop noise wise but you knew it was in. Make sure it is warm out and greased as others have said.
 
Thanks for all the advice. I started to order the Red Rubber Grease from Amazon, except I am tired of waiting as it won't arrive until after the weekend, on Tuesday, and today is Thursday. I had some axel grease and it tried using that, but I will get something from Autozone. I attached the insulators on first, then put the clamps on to hold them in place. Then I made sure I put the 2nd clamp on top, arranged so that a long screw driver could reach the screws to tighten. Will get the grease as I don't think I put enough axel grease on the insulators.
 
I don't know how critical it really is, but in theory petroleum based lubricants shouldn't be used on rubber because it will slowly break down the rubber. Silicone lube is recommended for rubber applications. So, I'd wipe off the axle grease you applied and start over with a silicone lube. If you have trouble finding it, I bought mine at a pool supply store.
 
I ordered the Red Rubber Grease anyway, can always use it. Any other suggestions so I can seat the carbs this weekend?
 
yes, buy some silicone grease locally, and just keep trying, they will eventually go in.
 
If you have 30 minutes to kill, this is interesting (and relevant to the current thread):


I had the concerns about using it as well (didn’t think to use the red grease/ wasn’t aware of its existence when I did the work, but again, it was only a little WD- not soaking in it).
 
I got the Red Rubber Grease. Is there a particular way the clamps are to be put on the insulators. Anyway got it pushed down and hopefully it has no air leaks. This is not any easy job. Making sure all the hoses are all connected underneath the carbs. I put the throttle cables on and found that the 2 different size screws that attach the cables, anyone know what the part numbers are for the 2 screws that attach the plate for the throttle cables. I found among all the screws, one phillips screw fits, but the bottom screw I can't seem to locate, so have to order that screw, but need to know either the part number or the thread pattern that fits. I hate working on this just due to a leaky coolant.
 
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Top screw is 5mm dia X 6mm length with a 0.8mm thread pitch

Bottom screw is 4mm dia X 8mm length with a 0.7mm thread pitch

Both have captive washers but you should be able to go to an ACE Hardware and get a 4mm Philips head screw, 8mm long and a 4 mm washer and be good to go.
 
Top screw is 5mm dia X 6mm length with a 0.8mm thread pitch

Bottom screw is 4mm dia X 8mm length with a 0.7mm thread pitch

Both have captive washers but you should be able to go to an ACE Hardware and get a 4mm Philips head screw, 8mm long and a 4 mm washer and be good to go.
I think you have the correct diameter and thread pitch for both screws, but the lengths may not be correct.

Oddly enough, the Honda fiche for various years has one screw unlisted in the parts descriptions for some years, and the other screw unlisted for other years. From what info is there it appears that the 5mm screw is 12mm long, and the 4mm screw is either 10mm or 14mm long (two part numbers specified).

These screws probably don't need to be the exact length as the Honda parts, so something in the 10mm/12mm/15mm length range should work. From the looks of the bracket it would seem that the 10mm length is long enough, and get a couple lock washers to keep them from vibrating out.
 
You are absolutely right, this bracket is off a '93 and looks like the 5mm is 12mm long, the 4mm is 14mm long when I put the ruler to them.

I blame it on acting before my second cup of coffee.
 
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