Coolant leak from the expansion tank overflow pipe

[kraftykarper]

I think this may have been covered before but I haven't seen exactly this proplem. Temp guage always displays just above cold when riding, and only reaches warm when engine fully warmed up. Never gone in the red.

Mines an 2007 955i, probably the last one made! Done about 23,000 miles. A few days ago I noticed the coolant was below minimum mark when the engine was cold. So topped it up to max, with bike level.

It was a hot day, and when I got to work coolant had gone beyond Max, and overflowed from the pipe, just in front of the back wheel. Leaking out. When bike cooled it was back to well below min. Never done this before. Done it a couple of times now.

The handbook advises to check levels when the engine is cold, and if not between min and max, to top up to max. I've never noticed this before, and had the bike about 2 1/2 years. Did a trip to the Pyranees on it, no problem.

Could the thermostat have failed in the shut position, and not allowing coolant to flow round the system?

No signs of leaks anywhere else.

Any ideas ,anybody had this experience?
Would appreciate any advice.

[trophydave]

I have to confess that I don't have a Tiger but I have owned a Trophy and have a Sprint ST.If I filled the expansion tank to the full mark on either of these it would blow some out through the overflow until it reached about the halfway point.I would be tempted to fill the tank halfway rather than full and see what happens.Also the radiator caps on Triumphs don't seem to last very long,it might be worth getting it pressure tested or replacing it.

[kraftykarper]

Thanks for that, I;ll try the half fill trick, and see what happens. I dont think the handbooks very clear on wether you check it with engine cold, or hot.

Logically I would think that when the engine warms up the coolant must expand, so starting with the coolant at the max mark with a cold engine, it would suggest that when the engine warms up it would expand, and overflow.

The other solution is trade in for a new tiger 800 !

[metalguru]

Not sure why Triumph handbook states fill to top when cold when the rest of the world uses the lower mark as cold mark and the top mark the hot limit. Rule of thumb is if the level exceeds the top mark when hot, then take some coolant out untill it does. Of course it does depend on coolant circuit design but the theory does work in practice.

[kraftykarper]

Thanks for the tips. I filled the expasion tank to half way between min and max, when the engine was cold. It still overflowed a little when the engine reached normal temperature, and the cooling fan cut in.

Now the engine is cold the level is at the minimum mark. So I'm going to leave it alone, but keep an eye on the level.

The temperature guage has never gone above the mid way point, and always stays just above cold when the bike is being ridden. It only ever reached the midway point during the summer, and when I was riding in town.

I think its a case of owner stop interferring!!

I am taking a tiger 800 out on a test ride tomorrow, so that might "cure" the problem!

[blacktiger]

kraftykarper, you could be due a rad cap as Trophydave suggests. Although mine lasted 10 years they're not all equal if you know what I mean.
Also, it may be a good time to completely change the coolant. Do you know when it was last done? Every two years in the norm as the antifreeze wears out according to the number of heat cycles it does.

Still, all that's irrelevant because you're just about to get a T800(XC). My advice is to try both types then buy the XC as it's much better all round.

[kraftykarper]

Well, I did the deed, and traded in the faithfull Tigger, for a Tiger 1050.

I;ve been thinking about one of these for a long time. I tested the 800xc. Its a great bike, but the 1050 felt just like my bike, but much better. We are thinking of another Pyranees trip next year, and I think the 1050 would be a more suitable, if not comfortable ride. Its just seemed more bike for the money, and came with all the Triumph luggage.

[birddogone]

Krafty,
I just bought a 06 Tiger and the first time I let her warm up in the drive way she started leaking antifreeze from the front of the fairing. After removing the the fairing and looking closer, the "L" fitting was sheared off cosing the leak. Replaced the part and all is fine now.
Rod

I have to confess that I don't have a Tiger but I have owned a Trophy and have a Sprint ST.If I filled the expansion tank to the full mark on either of these it would blow some out through the overflow until it reached about the halfway point.I would be tempted to fill the tank halfway rather than full and see what happens.Also the radiator caps on Triumphs don't seem to last very long,it might be worth getting it pressure tested or replacing it.

[Bixxer Bob]

You'll find, as you settle in and do some background reading, that this is a very common problem and most folks replace them before they break. Easy for me to say, I've been here a while. 

[metalguru]

Had the same problem but the problem was getting hold of the fittings,
have a look here

http://www.tigertriple.com/forum/index.php/topic,12043.msg88287.html#msg88287