Acceptable Engine Temps when Climbing Mountains

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Thanks for the links. They're very helpful. My ST is a 2003, so it was made before the elbow was put on the top or round hole. Unfortunately, that's where my bike is leaking from. The link says if the bike is weeping from here the water pump needs to be replaced. Has anyone been down this road before? The service manual talks about hydraulic presses and special tools required to remove and install the impeller, oil seal, and bearing. That's beyond what I have lying around my garage and probably my expertise level as well. Is it important to replace the water pump now or is it something that can wait, as long as the bike isn't overheating? Has anyone done this repair themselves?
 
I have not replaced one but several on this forum have, so maybe that can be more specific in their replies to you.
The press is suggested because the impeller needs to be pressed in to the mechanical seal to a very specific dimension and using a press makes this a more likely successful endevour.

In short, I can't offer you a hard and fast answer about how urgent a requirement this is. Whether or not replacement is urgent would depend on how badly it leaks, which seals are leaking, and how much the leak rate increases over how long a time frame if it does begin to do so. The possibility that the oil seal begins leaking and allows anti-freeze to get in to the engine is not a desirable outcome. Again, people who have been through this are better placed to answer you.
 
Before you replace the water pump, make sure the leak you’re seeing is actually coming from the round weep hole and not the rectangular opening in the same area. If it’s coming from the rectangular opening, the leak will be from one of the hoses or connections in the valley of the engine, not the pump. It’d suck to replace the pump and still have the leak.
Honda later added a drain hose to the WP weep hole to avoid this confusion. I suspect Honda replaced a lot of water pumps under warranty only to find the leak was really just a loose hose clamp.
 
If you do end up needing a new water pump, and decide to have a shop do the work, make sure they have done this before on ST1300s. We have had reports that mechanics unfamiliar with the bike have improperly installed the new pump (see @Andrew Shadow's comment about pressing the pump in to a specific depth). In fact, there seem to be more stories about dealerships that screw up repairs on these bikes than dealerships' service departments with happy and satisfied customers.
 
I think it mentions weeping 'significantly' - or something similar in later manuals. I have read that Honda were getting a great number of warranty replacements due to fluid leaking from that hole - after which they changed the wording in the manual, and fitted a tube to the weephole so that it wasn't readily visible.

Someone will correct me if I am wrong, but the hole (I think) drains a void between the seal for the water pump and the seal for the crankcase. If fluid is draining from this hole then it isn't entering the crankcase !! A little is to be expected to seep out.

The real issue is how long does it take your fluid reservoir to go down the the bottom mark ? If it does it in a few weeks then you have a problem. I never had to top mine up between services - 12-18 months. Somewhere in between there will be a scale where you can 'put it off' for a while. I suspect that if it is dropping fairly quickly then at some point it will 'suddenly' fail and you have no more coolant left.

This is an opinion only. I've never done it. I've inspected the hole on my A6 and the tube on my A9. I've noted a few drips, read that a few drips is of no concern (in later manuals) and I never got stranded in a cloud of steam at the side of the road. And I read a lot about it out of curiosity.

Please correct anything that I have wrong in here. I no longer have my ST1300 - I got a torn muscle, brother got an unexpected Christmas present and he now has all of my manuals. So this is written from memory, and only a fool would rely on that. What ? Just me then !
 
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Yesterday I fired my ST up on its center stand and let it warm up until the fan went on. In that time, it dribbled out the weep hole just enough to run to the bottom of the water pump cover, but not enough to drip on the floor or even have a drop forming on the bottom of the engine case. I'm guessing that isn't significant enough to worry about. I'm going to put the tupperware back on, ride it, keep checking for leaks, and keep a close eye on coolant level. Thanks for everyone's help.
 
SMSW said:
I always took the fairing apart. While you can probably get the cap off without taking everything apart, you won't be able to check the right side of the engine for coolant tracks (blue/green deposits on the side of the engine near the square and round drain holes). Too, adding coolant if necessary will be dicey. While you are in there (fairing off) it's a good idea to eyeball the hose clamps. To get to the thermostat, if necessary, you will have to remove the radiator (after undoing the fan's electrical connectors using a tiny screwdriver and removing the fastening screws, ]pull the bottom of the radiator forward as you lift it up off the top hooks. Then remove the frame cross brace in front of the thermostat housing*. Don't just try to pull it forward without that tilt.

The hose going from the radiator cap's fitting to the overflow bottle is notorious for splitting on older bikes. Be sure to check this too for leaks.

*You can also reach the 'stat housing from above - by removing the gas tank, air filter housing, etc.
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There is three fixing bolts for fixing the radiator - upper left, lower left, and lower right. After that you slide the radiator slightly to the right so it slides off a fixed metal pin on a bracket which goes in a grommet on the upper right side of the radiator. I don’t recall there’s a need to tilt the radiator forward, but you do have to move it to the right to remove it. Indeed, if you leave the front wheel and fender in place, tilting the radiator forward may scratch the fender when the radiator comes out, clearance is tight.
 
dduelin said:
There is three fixing bolts for fixing the radiator - upper left, lower left, and lower right. After that you slide the radiator slightly to the right so it slides off a fixed metal pin on a bracket which goes in a grommet on the upper right side of the radiator. I don’t recall there’s a need to tilt the radiator forward, but you do have to move it to the right to remove it. Indeed, if you leave the front wheel and fender in place, tilting the radiator forward may scratch the fender when the radiator comes out, clearance is tight.
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Our recollections are different. I remember that pin being L shaped, horizontal with the leg pointing up. Tilting the radiator forward allowed me to lift the radiator w/ its grommet off that pin.

My memory is never wrong, it's just not always right. :rofl1:
 
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