Maybe after the second purge refill beginning with undiluted coolant in the amount of half the system capacity. Then top off with distilled water. You might end up over a normal 1:1 coolant to water ratio but will not be under.
ST1100 coolant replacement odd procedure
- Thread starter ChriSTian_64
- Start date
Compare the Allen Millyard maintenance methods on his Special bikes . A quick check on nut tightness on the wheels and brakes. Then a top up for the coolant . Screws cap back on . Gets on bike and rides away . No awkward bolts . No plastic covers .
bdalameda
PaleoCyclist
Good job!
Most coolant leaks on the ST1100 come from shrunken hoses and loosening clamps with age and also with temperature drop in the winter. I've seen a lot of drips begin occurring when it gets cold out and small puddles appear under the bike in the garage.
I am an advocate of the Evans waterless coolant - I have used it for many years in all my vehicles and it is almost a permanent coolant and does not require changing for at least 500K miles, as there is no water in it to cause oxidation inside the engine and components and because there is no water in it, very little pressure builds-up with heat so hoses, seals and gaskets are not subjected to pressure degradation. You can literally take a radiator cap off a hot engine without danger of coolant blowing out. My elderly 97 ST1100 internal radiator and cooling system still look brand new inside. Many posts about this in the past and many opinions - I certainly don't want to start a long-winded thread.
Most coolant leaks on the ST1100 come from shrunken hoses and loosening clamps with age and also with temperature drop in the winter. I've seen a lot of drips begin occurring when it gets cold out and small puddles appear under the bike in the garage.
I am an advocate of the Evans waterless coolant - I have used it for many years in all my vehicles and it is almost a permanent coolant and does not require changing for at least 500K miles, as there is no water in it to cause oxidation inside the engine and components and because there is no water in it, very little pressure builds-up with heat so hoses, seals and gaskets are not subjected to pressure degradation. You can literally take a radiator cap off a hot engine without danger of coolant blowing out. My elderly 97 ST1100 internal radiator and cooling system still look brand new inside. Many posts about this in the past and many opinions - I certainly don't want to start a long-winded thread.
bdalameda I have never heard about the Evans coolant till today . I watched the Jay Leno video about it . Does the ST1100 radiator need any alterations and is the brass thermostat still used ? Also is the deterioration in rubber tubes coming from outside (atmosphere or oxygen or heat ) or inside the tubes from water coolant plus additives ?
I won't claim to be an expert on the subject, but I've always heard that coolant hoses tend to deteriorate from the inside out. As a result of that, hoses that look good to the eye may actually be very close to failing, and is why people tend to replace them periodically, rather than rely on visual appearance to determine when its time to change them.
Thanks for the solid information about tubes .If the water mixture is exchanged for the Evans glycol mixture then some water remaining must be flushed out . One odd idea was to use a wet /dry suction with some Evans added beforehand to get it out . Those 2 very awkward flushing bolts that puzzle everyone must be get-at-able with a jointed socket spanner . Or a double jointed one .That could help to reduce the maintenance .
I keep thinking about the tubes "trapped " under the carbs. Why did Honda not put them on top of the carbs and raise the carbs to allow the air filter to slide underneath ? The fake tank is just a fancy anomaly . Just a minor innovation .I should get in touch with Allen Millyard for that . Moving stuff around like that makes the ST 1100 like a rubic cube . How about splitting the carbs ,Two each side with a long narrow air filter in between ?
While we are at it extend the rear mudguard to stop salty water splashing on the swinging arm .
The small drain bolts should be accessible with some ratchet spanners .They have open end spanners at one end and ring ratchets at the other end joined with a hinge /pivot .The only thing needed is enough angle movement to work the ratchet clicker .
If you want to drain coolant from the rubber hose at the bottom of the radiator I would be better to fit a brass connector .Cut out a section of the hose and fit a threeway junction from your plumbing kit . The centre section can have a blanking bolt pointing down to release the coolant . Compression Equal T 22 mm is the phrase for that . Remove the two end nuts and fit the hose both ends on the threaded parts with jubilee clips .
I keep thinking about the tubes "trapped " under the carbs. Why did Honda not put them on top of the carbs and raise the carbs to allow the air filter to slide underneath ? The fake tank is just a fancy anomaly . Just a minor innovation .I should get in touch with Allen Millyard for that . Moving stuff around like that makes the ST 1100 like a rubic cube . How about splitting the carbs ,Two each side with a long narrow air filter in between ?
While we are at it extend the rear mudguard to stop salty water splashing on the swinging arm .
The small drain bolts should be accessible with some ratchet spanners .They have open end spanners at one end and ring ratchets at the other end joined with a hinge /pivot .The only thing needed is enough angle movement to work the ratchet clicker .
If you want to drain coolant from the rubber hose at the bottom of the radiator I would be better to fit a brass connector .Cut out a section of the hose and fit a threeway junction from your plumbing kit . The centre section can have a blanking bolt pointing down to release the coolant . Compression Equal T 22 mm is the phrase for that . Remove the two end nuts and fit the hose both ends on the threaded parts with jubilee clips .
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Has anyone mentioned the size of the 2 drain bolts ? It`s 10 mm both sides. The right side is easy to reach. Left side can be reached with a fixed ratchet spanner so a flexi ratchet spanner would be easier . But I don`t know if the ratchet will click with a tube in the way . Maybe a short stubby flexi ratchet will have enough room .My ratchet spanner has a clicker angle of about 15 degrees . To save twisting my back or laying flat on a dusty concrete floor I can cut out a 20 degrees cardboard angle and if the point of the cardboard reaches the nut centre the ratchet should work Did Honda say "Take off the exhaust pipe "? There`s something wrong with that . The other way is a socket rod pointing straight at the nut with a double hinge on it . Less likely .
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Is this your first Honda?? Part of the Honda design philosophy is to force you to remove as many parts as possible to access anything and everything. In the case of those coolant hoses I don't know how many other viable options would have been available given the V-4 layout. I've owned other 4 cylinder inline engines that didn't require anything like that at all, just two hoses to the radiator, so it was a choice Honda accepted given that they wanted the V-4 configuration.
ST1100Y
Site Supporter
Which brings the question if a swap to silicone hoses would bring any benefit in matters of longevity...
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Ain't only Honda. Last fall I had to replace the serpentine belt tentioner on my car. This required me to loosen and remove a motor mount so that I could jack the engine up to get enough clearance to remove the bolt from the belt tentioner assembly. Tried getting that sucker out but would not clear the frame. Don't know why Toyota did not put a hole in the frame so that bolt would clear frame.
We need a chemist to decide if the Evans glycol mixture will deteriorate silicone pipes. But the 4 way carburetor design could be divided into two pairs to make access much better . We seem to have two threads going here . One lot lot say don`t do anything different ,and the other lot say you can`t ever do anything different .Two points of view with the same result . Neither side is happy with forums for similar reasons . They just want a cosy chat about having a beer . I have nothing against beer btw.
For the two small drain bolts the access is best with a 10 mm ratchet (ring )spanner 8 inches long. I have a 6 inch one but that is less easy . If you mentally draw a line from the left side bolt down towards the exhaust pipe where it begins to turn upwards ---that is the lowest angle for the spanner.The limit is set by the metal box section protecting some electrical connectors (starter motor cable etc ) . I found the possible access angle was greater than 20 degrees . More like 30 degrees . For Replacing the left side nut just use a bit of masking tape inside the ratchet hole and jam the nut into the spanner tight. It will hold the nut until the thread starts connecting . Use a wide screwdriver to help with that .For visual help , the nut on the left is just forward of the front exhaust heat shield top edge and a little lower .I hang a small lamp on a wire hook dangling from the spark plug cable to see it .
Problem solved . Just make sure the ratchet clicks the right way. They should put green and red paint on them . I tried to reach the left side bolt with a universal joint socket but first I had to unscrew the heat shield. But the socket kept flopping down and was a pain so a straight fixed ratchet spanner is best. I also added copper grease to the heat shield bolts .
Problem solved . Just make sure the ratchet clicks the right way. They should put green and red paint on them . I tried to reach the left side bolt with a universal joint socket but first I had to unscrew the heat shield. But the socket kept flopping down and was a pain so a straight fixed ratchet spanner is best. I also added copper grease to the heat shield bolts .
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Thinks "Am I aware this thread is a year old?" It does not matter how old the thread is if the answer was "Don`t work with open end spanners if you can use ratchet ring spanners ". And I have had 3 other Honda bikes and taking the silencers off instead of using a six inch ratchet ring spanner is fairly obviously wrong . The instructions are wrong .
Going to be changing out my 4 year old coolant here soon. I think my method will be get a gallon of coolant. Use half to flush it and the other half as the final fill and call it a day. Like many others never have fooled with the head drain bolts.
A quick training session on 6 inch ratchet spanners will cure the problem. Maybe we can organise a certificate to show proficiency . The question to me asking if this was my first Honda was ok but it had double question marks . That was a bit heavy to bear .
I tackled the right side drain bolt today with a ratchet ring spanner.The shallow head of the bolt does not allow the complete coverage of the spanner but it shifted quite easily . Winding the bolt out The threads are still gripping when the spanner starts to jam against the frame. The bolt only just gives enough clearance to get the spanner out of the way before the coolant flows out. I had topped up the coolant beforehand to get a good flushing action . There was a lot of dirty rust coloured liquid cleared out .
I took the bolt and shaped the end of the thread to 45 degrees for about 1/8th inch , to make replacement possible .That worked perfectly . I jammed the bolt in the spanner with some masking tape to stop it falling away before the threads gripped .
The left side bolt was too tight to shift today so I may cobble together an extension for extra leverage . There are too many sharp edges to catch my fingers if I push too hard and it suddenly gives way . I needed a mat to kneel on and a padded stool to hold me in position .The narrow led light torch just had a nice slot to keep the bolt visible . This bike is basically a rolling nightmare . Lets be honest .
I took the bolt and shaped the end of the thread to 45 degrees for about 1/8th inch , to make replacement possible .That worked perfectly . I jammed the bolt in the spanner with some masking tape to stop it falling away before the threads gripped .
The left side bolt was too tight to shift today so I may cobble together an extension for extra leverage . There are too many sharp edges to catch my fingers if I push too hard and it suddenly gives way . I needed a mat to kneel on and a padded stool to hold me in position .The narrow led light torch just had a nice slot to keep the bolt visible . This bike is basically a rolling nightmare . Lets be honest .
I opted not to try and break loose 30 year old engine drains on my '92. Instead, I bought a quantity of distilled water and repeatedly ran the bike and drained and readded distilled water until the output was relatively clear. Then add 100% undiluted antifreeze in the amount of half the system capacity. Top off with more distilled water and you are done.
rwthomas1
Site Supporter
Probably should ask why coolant is changed. Coolant breaks down over time, and the additive package of chemicals that inhibit corrosion, etc. are used up. Cooling systems are closed systems. The only way crap gets in there is if its there from manufacturing, or someone puts it there, or if the coolant hasn't been changed in this century and has deteriorated. That is not what I'm talking about here, I'm talking about well maintained systems that are functioning normally.
Given this information, I moved to a partial replacement method years ago and it has stood me well, never had any coolant issues on anything I own. So here it is: Whatever the recommended coolant change interval is, cut it in half. That is the new change interval. Pull off hose, open valve, etc. at the lowest point you can find in the system. Whatever drains out, drains out. Close up system, re-fill with fresh coolant, burp system, run engine, etc. check for leaks and return to service.
Every cooling system I've ever seen will dump at least 60-70+% of its volume just by removing the lower hose, or draining at the lowest point. When I've been able to I measure what is drained, I compare it to the capacity specifications its always been most of the coolant in the system. The more frequent change cycle more that replenishes the additive packages, and I'm convinced the new silicate-free coolant formulations make flushing a relic of the past. When I do have to crack into a cooling system, they have been clean as a whistle inside, so it appears to work.
I realize this is anecdotal, and goes against conventional wisdom, but I've done it successfully for a couple decades on multiple vehicles, some of which now have 330+K on the odo.
YRMV, don't try this at home, etc.
Given this information, I moved to a partial replacement method years ago and it has stood me well, never had any coolant issues on anything I own. So here it is: Whatever the recommended coolant change interval is, cut it in half. That is the new change interval. Pull off hose, open valve, etc. at the lowest point you can find in the system. Whatever drains out, drains out. Close up system, re-fill with fresh coolant, burp system, run engine, etc. check for leaks and return to service.
Every cooling system I've ever seen will dump at least 60-70+% of its volume just by removing the lower hose, or draining at the lowest point. When I've been able to I measure what is drained, I compare it to the capacity specifications its always been most of the coolant in the system. The more frequent change cycle more that replenishes the additive packages, and I'm convinced the new silicate-free coolant formulations make flushing a relic of the past. When I do have to crack into a cooling system, they have been clean as a whistle inside, so it appears to work.
I realize this is anecdotal, and goes against conventional wisdom, but I've done it successfully for a couple decades on multiple vehicles, some of which now have 330+K on the odo.
YRMV, don't try this at home, etc.
I think you're onto something. Changing at anywhere near the manufacturers recommended interval seems to keep a system clean as a whistle. Manufacturers know that most customers will not adhere to book intervals so there seems to be a large neglect factor built into recommendations.
I was lucky to get the right side bolt out with the ratchet spanner .When I reached the limit of the screw thread It just dislodged enough to get it out . For anyone trying ,this change back to using an open ended spanner for the last bit . If the thread had been a tiny bit longer I would have had to wind in the screw far enough to get the ratchet out .A piece of leather and some long nose pliers would have done it .
The bolts are at the lowest point of the cooling system . To take of the rubber hose on the radiator is risky because the aluminium radiator is soft metal and the nozzle can be easily distorted . Removing the other end is better . Or cut the hose and fit a copper sleeve and 2 jubilee clips . Or use a brass equal T connector and clamp the hose ends on the threaded parts .
This is just about how to get the coolant out (mechanically ). These durable engines will be running long into the electric vehicle years .But solving the drain bolt puzzle is a bit like solving a Rubic Cube .
The bolts are at the lowest point of the cooling system . To take of the rubber hose on the radiator is risky because the aluminium radiator is soft metal and the nozzle can be easily distorted . Removing the other end is better . Or cut the hose and fit a copper sleeve and 2 jubilee clips . Or use a brass equal T connector and clamp the hose ends on the threaded parts .
This is just about how to get the coolant out (mechanically ). These durable engines will be running long into the electric vehicle years .But solving the drain bolt puzzle is a bit like solving a Rubic Cube .