Honda ST1100 1994 - two (drain?) holes on the back of both sides cylinders

aquilaalba

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May 12, 2016
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Swansea, UK
Hi all, I've got a problem with my ST1100, it's leaking from left side hole on the left cylinder block. Does anyone know what is the purpose of these? They're on both sides and I've found photos of engines with same holes on them, so I take it is a standard thing on them? Mine leaks when warmed up, just wandering what it might be? Any ideas?

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Currently floating in a number of topics around here...

Those are the drains for the plug holes, allowing rain/washing water gotten by the plug-caps to exit...
 
What exactly is leaking? If it's leaking oil then the part of the valve cover gasket that seals the spark plug tunnel is bad, fairly easily and cheaply fixed. Note that these holes are in the cylinder head rather than the block. Not sure what to think if there's coolant leaking there as the head gasket would be below these drains leaving only a damaged head casting. Unlikely to leak on both sides though. What do you see down in the spark plug tunnel when you remove the cap?
 
It's the coolant, slow when cold and speeds up (but not massive amount). I was just wondering if that could be connected to something else than the drain for plugs... It's not connected to any other overflow or something? Thanks for that.
 
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Aquila- this seems to be a continuation of a previous thread you started on the same problem ( last post was on the 23rd of this month and made by you). you're making it difficult to follow, or even give sound advice, without the full story to allow members to "reason out the problem" and offer advice...other than receive the same replies you've already got
 
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aquilaalba said:
It's the coolant, slow when cold and speeds up (but not massive amount). I was just wondering if that could be connected to something else than the drain for plugs... It's not connected to any other overflow or something? Thanks for that.
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OK. if it's coolant then I suspect one of the hoses or elbows under the carbs. It's probably just running out of the "V" of the engine, past and perhaps hanging up at those holes in the head and not actually coming from there. I can't think of any way for coolant to come from those spark plug tunnels short of two severely cracked heads and there are no reports of that ever happening.
 
wjbertrand said:
OK. if it's coolant then I suspect one of the hoses or elbows under the carbs. It's probably just running out of the "V" of the engine, past and perhaps hanging up at those holes in the head and not actually coming from there. I can't think of any way for coolant to come from those spark plug tunnels short of two severely cracked heads and there are no reports of that ever happening.
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I would first suspect a bad coolant elbow o-ring or coolant elbow itself cracked.........a notorious issue with these ole' ST1100's;).
 
Not sure how else could I get that back in order, hence this - here's the link to my previous post which has became more of a blog than forum posts - hence new thread starting seemed like a good idea with more specific matter to resolve. Original thread below, also - newest photographic evidence addition - seems much like leaking from elbows...

ST1100 Pan European - long time dream (crippled) came through - head gasket?

Thank you for all replies.
 
Looks like massive intergranular corrosion.
 
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