gilbertdave Posted June 26, 2011 Report Share Posted June 26, 2011 Hi All, Was getting my stuff together this morning to go off for a ride and noticed that the bike was a bit wet. Having started the bike, there was definitely a flow of water coming from the cooling system. It appeared to be coming from rad, but I couldn't really see whether it was actually the rad or one of the connecting hoses. The bike has overheatted (blown out steam) twice fairly recently. In both cases I killed it straight away and let it cool down, checked / added coolant as required and it was ok again. I'm guessing if there is a leka in the system it makes sense for it to boil over? So, can I repair the rad (with rad weld or something similar) or am I looking at replacement partS? Anyone with any knowledge can no dount shed some light on it for me Thanks in advance, Dave Quote Link to comment Share on other sites More sharing options...
pedronicman Posted June 26, 2011 Report Share Posted June 26, 2011 Hi All, Was getting my stuff together this morning to go off for a ride and noticed that the bike was a bit wet. Having started the bike, there was definitely a flow of water coming from the cooling system. It appeared to be coming from rad, but I couldn't really see whether it was actually the rad or one of the connecting hoses. The bike has overheatted (blown out steam) twice fairly recently. In both cases I killed it straight away and let it cool down, checked / added coolant as required and it was ok again. I'm guessing if there is a leka in the system it makes sense for it to boil over? So, can I repair the rad (with rad weld or something similar) or am I looking at replacement partS? Anyone with any knowledge can no dount shed some light on it for me Thanks in advance, Dave Quote Link to comment Share on other sites More sharing options...
jse Posted June 27, 2011 Report Share Posted June 27, 2011 Hi All, Was getting my stuff together this morning to go off for a ride and noticed that the bike was a bit wet. Having started the bike, there was definitely a flow of water coming from the cooling system. It appeared to be coming from rad, but I couldn't really see whether it was actually the rad or one of the connecting hoses. The bike has overheatted (blown out steam) twice fairly recently. In both cases I killed it straight away and let it cool down, checked / added coolant as required and it was ok again. I'm guessing if there is a leka in the system it makes sense for it to boil over? So, can I repair the rad (with rad weld or something similar) or am I looking at replacement partS? Anyone with any knowledge can no dount shed some light on it for me Thanks in advance, Dave Dave, You need to find the source of the leak first as the solution will relate to the cause. If you can't find the leak, that also will be good information for us to base advice on. Jon Quote Link to comment Share on other sites More sharing options...
dan williams Posted June 27, 2011 Report Share Posted June 27, 2011 Hi Dave, yes a cooling system must be pressurized to work. The normal working temperature of the system is above the boiling temperature of water at 1 atmosphere. As a cooling system heats up it builds up pressure so the water in the system can be heated above 100C without boiling. By operating the cooling system under pressure it can be made much more efficient at removing heat. That's why a pinhole will cause a cooling system to boilover. The pinhole keeps the system from pressurizing so before the water can reach operating temperature it boils (changes from liquid to gas) this spikes the pressure in the system dramatically causing the pressue release valve on the radiator (or some other weaker part of the system) to release the steam in one big spurt. Quote Link to comment Share on other sites More sharing options...
gasser_david Posted June 27, 2011 Report Share Posted June 27, 2011 Hello Is fan running when it boils up... david Quote Link to comment Share on other sites More sharing options...
gilbertdave Posted June 28, 2011 Author Report Share Posted June 28, 2011 hi, Yeah, the fan does run and the rad seems to be free of gunk and rubbish. I'll make some time and try and identify where the leak is coming from... watch this space. Quote Link to comment Share on other sites More sharing options...
gilbertdave Posted June 30, 2011 Author Report Share Posted June 30, 2011 Right... Just had a bit of a go at identifying the problem... Without luck. I let the bike run for ten minutes or so until it was nice and warm. I saw two tiny drips of water ( like the size of drip you get from a pipette ) but nothing more. But, as the bike got warmer I could see tiny wafts of steam. I didn't let the bike boil up completely but there was a fairly constant puff of steam. I couldn't see where it was coming from though... My best guess is that it is coming from the top right hand corner of the rad, on the side facing the ground. It's also worth noting that the radiator did not come on. I have definitely seen the rad running whilst riding so I know it works, but I don't know whether the bike was hot enough to warrant it coming on this evening... The fact it was steami makes me think it was plenty warm! Any thoughts would be welcome.... Rad weld? Bubble gum and snot? Etc etc. Dave Quote Link to comment Share on other sites More sharing options...
gasser_david Posted June 30, 2011 Report Share Posted June 30, 2011 Obviously best option to find leak and resolder. However next best option is to try sealant method. Personally not a radweld fan, as used twice on "problem" car and didn't cure problem of small leak. Used a product on later car with similar problem.... contained copper coloured particles in a clear liquid...cannot remember name..will look in garage to see if any left.. which worked. Suppose that's the downside of running 15 year old cars with 15 year old rads.... Note that once you've added some 'gunk' or other it's deposits are in there forever.. Could try old 'hole in tube' trick if you have a way of pressurising rad whilst underwater...not with rad still on bike though!! Hope this helps as I know what a pain it can be. david Quote Link to comment Share on other sites More sharing options...
gilbertdave Posted July 1, 2011 Author Report Share Posted July 1, 2011 I would be inclined to go with the sealing method (mainly because it would seem to be the simplest option). Is anyone aware of any long term problems with using sealer? If not, does anyone know the best product to use? Quote Link to comment Share on other sites More sharing options...
legionnair Posted July 1, 2011 Report Share Posted July 1, 2011 I would be afraid to use a sealer because it has abrasives in it, even the coolant is a non-abrasive type. Cause bikes use a soft rubber like seal it will wear out quicker. It works in automotive seal cause they use to ceramic disks as the seal so they can handle it better. Sounds like you need to remove the rad and find some expanding rubber plugs and pressurize and submerge in water. Good luck Quote Link to comment Share on other sites More sharing options...
gilbertdave Posted July 4, 2011 Author Report Share Posted July 4, 2011 (edited) Right... I took the easy route and tried RadWeld. I followed all the instructions and let the bike run etc. then tried it again on Saturday morning. The only noticeable change was that the water spewing out had changed from blue (coolant) to red (radweld)... bad times. So, Saturday afternoon it was over to Dad's to get the bike in bits. We drained out the coolant and flush the system to clear out the radweld and any other gunk and then pulled the rad out. The first thing we noticed is that one of the spade connectors on the temp sensor was disconnected... Once the rad was out, we noticed straight away that the filler neck was badly twisted. Pressumably by someone over tightening the filler cap. To confirm that the tear was in fact leaking, we blocked up one hose and connected a low pressure air supply to the other... some bubbly water showed us that the filler tube was leaking quite badly! I followed some instructions I'd seen, we tried to solder it... without success. I'm guessing the rad is aluminium. So, next effort was Araldite. We used a solvent to clean the area (particularly as it was now covered in soldering flux) and lumped on as much araldite as we could get in the area. Thanks to the warm british sun. the araldite went off in 15 minutes and we retested. There were a couple of little leaks on the back end of the filler tube but we got them on the second attempt. You can't really see the araldite, but I can assure you its there! Finally, we tested the fan with a 12v supply and that worked ok Forgive the rubbish picutre quality (I phone!) Finally, reassembled everything to the bike and refilled with new coolant. I let the bike run for fifteen minutes or so and there was a bit fo steam to start with but that appeared to burning off spilled water... after ten minutes or so it was clear of steam and the fan was kicking in... happy days. I rode for about 2.5 hours yesterday in 24 degrees with no loss of water. I also saw the fan working as well. So, happy days.... for now! Thanks to the old man for his patient assistance. It really amazing the things Dad's know! Edited July 4, 2011 by gilbertdave Quote Link to comment Share on other sites More sharing options...
gilbertdave Posted July 17, 2011 Author Report Share Posted July 17, 2011 (edited) Right, i've been straddling two threads, but it seems my problems are based around cooling. I had some small success with the repair to the rad, but after a few hours it boiled up again. More concerningly, when it was boiling up the fan wasn't kicking in. So, after speaking to a local gas gas agent, he offered to take a look at the bike and he gave me some instructions to identify the problem. I set the bike up to run and we shorted the terminals for the temperature sensor to basically fool the bike into thinking it is hot, the fan ran as expected. We then put it back to normal and just ran the bike for thirty minutes or so... And, well.... it did exactly what its meant to. It warmed up, the fan came on it cooled down... repeatedly... So, I went a rode yesterday and within an hour its boiled up and the fan is engaging! Its really flipping annoying as each time i go out its an hour and half round trip in the car, plus loading / unloading the car etc. I'm now plnning to repalce the rad, temp switch and fan control unit... Surely something in there will sort the problem out! Edited July 17, 2011 by gilbertdave Quote Link to comment Share on other sites More sharing options...
dan williams Posted July 18, 2011 Report Share Posted July 18, 2011 OK the difference between riding and just sitting there running is load on the engine and usually higher RPM and throttle setting. So that leaves the most likely candidates as too far advanced ignition, too lean carburation. Possible low octane fuel, air leak in intake or primary side seal. Carbon buildup in cylinder head raising compression. I know this is uneven but just sort of stream of consciousness on this. Here Quote Link to comment Share on other sites More sharing options...
gilbertdave Posted July 20, 2011 Author Report Share Posted July 20, 2011 I've just replaced the radiator (with a second hand / non leaker), the temperature switch and the rectifier. I am very pleased to say that bike seems to be behaving. At least, it is regulating its temperature whilst riding about outside my house. The whole front end of this year has been driving towards riding at a trial this weekend at my local spot... so hopefully the bike behaves and I can ride it... As an aside, I know Jon (JSE) has been keeping an eye on this thread... Firstly, thank you for the wiring diagrams on trialspartsusa, they were most helpful. Secondly, why does Leonelli supply parts with two wires the same colour and seemingly no indication as to which is which? Its probably obvious if you know what you're doing, but I don't and two yellow wires is confusing?> Nevermind... fingers crossed for success tomorrow followed by success / surviving only my second trial on Saturday. Quote Link to comment Share on other sites More sharing options...
jse Posted July 21, 2011 Report Share Posted July 21, 2011 As an aside, I know Jon (JSE) has been keeping an eye on this thread... Firstly, thank you for the wiring diagrams on trialspartsusa, they were most helpful. Secondly, why does Leonelli supply parts with two wires the same colour and seemingly no indication as to which is which? Its probably obvious if you know what you're doing, but I don't and two yellow wires is confusing? Jim Snell, the GG parts importer for the U.S. makes those schematics and has collected all the info on his website. He's a wealth of information and happily, he's willing to share it with everybody. Not quite sure what Leonelli module you mean but usually the types of connectors dictate what is connected to what. "you know what you're doing".....you give me way too much credit... Jon Quote Link to comment Share on other sites More sharing options...
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