Will.wood Posted September 29, 2014 Share Posted September 29, 2014 Hi everyone, I'm new to the site. Hopefully someone can reply and give me an idea of what's going on, any help is appreciated. So I'll start from the start. I bought the 2001 dt 125 and rode it home (about 50 miles) on dual carriage ways and a roads and everything was fine, really pleased with my new purchase. About a month later I noticed water dripping from the coolant expansion overflow pipe from the frame. I rode it the next day to work and it seemed to get really hot. When I finished work I thought I'd top up the radiator only to find that it took nearly 500ml of water! Soon after that the water in the expansion tank started boiling and in the end managed to pop the cap of the tank! I searched around on the internet to see what the problem could be and after scouring forums of a lot of people with similar problems, I thought that the answer is the head gasket. Even though I couldn't see any leakage from the cylinder head I thought I'd give it a go anyway. So I changed the head gasket and got some brand new coolant. I couldn't find a cap/plug anywhere however so I had to get a different one which doesn't really fit well. It sort of just sits on top but fits the rim so I wrapped the cap on with some tape and put some zip ties on. For a few days it ran perfectly, not getting hot, but still leaked a little bit of coolant which I thought was down to me overfilling the radiator. I tried to ride it to college one morning and by the time I got about 8 minutes into my journey the temp gauge was going all over the place. So I stop and see that I've left a big trail of coolant behind me and it's all dripping over the floor (the coolant tank was also steaming but I guess this was because I had hardly any in there?) So if anyone has actually read that essay and has ideas I would be so grateful! I was thinking it could be the water pump maybe(?) but I'm not too sure. Thanks! Will Link to comment Share on other sites More sharing options...
Moderator Airhead Posted September 29, 2014 Moderator Share Posted September 29, 2014 will if the bike is ridden with the head gasket keaking it can in some cases warp the cylinder head, really you should have checked this when you fitted the new head gasket. If it is warped you'll have to have it skimmed flat again Link to comment Share on other sites More sharing options...
Will.wood Posted September 30, 2014 Author Share Posted September 30, 2014 Hi, thanks for the reply. Sorry I forgot to say I did check if it had warped with a flat edge on both the barrel and cylinder head and it was all good. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted September 30, 2014 Moderator Share Posted September 30, 2014 Hmm not sure checking with a flat edge will be good enough though, might have been a better way to ckeck the head on a piece of glass...see if it rocks like, smear it with oil, does it seal down to the glass etc when viewed through the glass. OK then look out fot bubbling in the coolant expansion tank ? Link to comment Share on other sites More sharing options...
Will.wood Posted September 30, 2014 Author Share Posted September 30, 2014 Ok thanks, will try this out later on this evening. Shall I check the top of the cylinder like this as well? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted September 30, 2014 Moderator Share Posted September 30, 2014 Ok thanks, will try this out later on this evening. Shall I check the top of the cylinder like this as well? nahh usually only the head will warp so no point disturbing those studs, best left alone and not messed with IMO Link to comment Share on other sites More sharing options...
Will.wood Posted September 30, 2014 Author Share Posted September 30, 2014 Well I checked the head again how you said and it all looks okay. However the gasket seems to have blown again! Lots of brown around the middle of it? Anyway I thought for now I'd try and reseat it and see if it worked. I set off 90 seconds up the road and pulled over to check everything was okay. The coolant tank had filled up a fair bit and was bubbling a little bit even though the tank felt sort of luke warm. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted September 30, 2014 Moderator Share Posted September 30, 2014 still leaking matey, it should NOT be bubbling and it should NOT be warm. Tell me are you using a genuine yamaha gasket, they have a thin black rubber coating? or are you using a naff cheapo painted metal jobbie bout as useful as a chocolate ashtray ? 1 Link to comment Share on other sites More sharing options...
Will.wood Posted January 7, 2015 Author Share Posted January 7, 2015 Sorry it's a bit late but I did manage fix it eventually. I did originally use a cheap metal gasket which I expect is why it blew again but I replaced it with a genuine yamaha one and and now it works perfectly and still is. Link to comment Share on other sites More sharing options...
Recommended Posts