farmerj Posted September 7, 2012 Report Share Posted September 7, 2012 Hi guys, '01 txt 321, seems to be running hot - the exhaust header is turning blue, and it just feels hot, the exhaust and all. Plenty of water in the radiator, and the fan is working. I'm wondering if there is a thermostat that can go bad? (I don't know how to check it...) Can the water pump impeller strip or quit pumping? I recently went to Boyesen reeds - am I running a bit lean? Just looking for some ideas. Jeff Quote Link to comment Share on other sites More sharing options...
goudrons Posted September 7, 2012 Report Share Posted September 7, 2012 I recently went to Boyesen reeds - am I running a bit lean? Jeff These can cause the engine to run lean. Don't Boyesen suggest upping the jets in the instructions?? Quote Link to comment Share on other sites More sharing options...
aussiechris Posted September 7, 2012 Report Share Posted September 7, 2012 Hi Jeff, There's no thermostat as such. It sounds like your thermo switch is working if the fan is turning on and off. Is it possible you got an air leak somewhere when you installed the reeds? I also installed Boysen reeds in my 321 and really like them. I did change the jetting slightly and it runs pretty fat (rich). I never had the pipe turn blue. If you just leave the bike idling, does the fan cycle on and off, or does it keep running? It should cycle and if it doesn't while idling for a long time, then it is probably a cooling system issue - radiator, pump or something. I've never heard of the pump stripping, the usual issue is the seal failing causing water in the gearbox oil. Chris. Quote Link to comment Share on other sites More sharing options...
sting32 Posted September 7, 2012 Report Share Posted September 7, 2012 (edited) Farmerj, Im not an expert as much as JSE, but I listen to him and others a lot, in person. I dealt with an issue like you have, but I'd not changed reeds to have it. My 2000 321, bike was bought from higher altitude (colorado >6000ft elevation, but riders usually up around 8-9 thousand ft when riding, so you have to lean out the gas to air mixture when you live or ride there. They use smaller jets (leaner). I took the bike home, ran it for about 30 minutes, kind of knowing I need to re-jet, but thought just idling shouldnt hurt it that fast. I blued the pipe. Fortunately there is a paste that you'll find in trucks-stops here in USA (chrome and trucking are you know big deal) that removed the bluing, fwiw. I cannot recall what it was, but man it worked so easy, when several other pastes I tried did nothing. The other thing besides the "engine's needs for fuel" that change of the reeds might have cause, that made your case more worrisome and magnified IMHO, is kind of reversing a "tip" big dog trials riders do. those old bikes had lots more "spinning" hardware than the pros, and compared to the newer bikes, they rev slower and were less snappy. So, apparently back then, better riders that wanted quicker throttle response; so it is likely, and probable, that along the life of that bike, someone tuned that carb with as close to LEAN as they thought they could get by with at his or your altitude (if altitude is the same for you both). This gives the bike a crisper response that more capable riders are looking for (it seems). I am kind of opposite, I like the bike richer, makes the snappyness just a wee bit less... Plus then you changed reeds that meant you were lean plus more lean, which could just cause it to finally blue the pipe. when pipe is blueing, it also can cause piston damage, so be warned if you are revving the engine under loads while lean. Other things, not posted above... make sure the antifreeze you use is 50/50. if it isnt mixed with water with less than 50% antifreeze 50% water (best results is exra-clean waters, not tap water), it will NOT cool as efficiently. if it doesnt get to -30F where you live, then mix it for your protection temps you will be. Southern California for example rarely dips below 40, lol so why have 50/50 that protects to something like -50F? I've always been told that plain water cools the best and is more efficient in cooling, technically, but you DO NOT want to run straight water, you need anitfreeze in there for anti bubbling/electrolysis prevention that they put in antifreez. I also use something that used to be called "water wetter" that my auto racing buddies use, seems to make the 50/50 a little more efficient. Try at your own risk though. All the above is also assuming the waterpump (there is a plastic impeller that can go bad) isnt damaged and other things mentioned by others like air leaks are not the CAUSE of your problems. Edited September 7, 2012 by sting32 Quote Link to comment Share on other sites More sharing options...
thats_a_five Posted September 7, 2012 Report Share Posted September 7, 2012 The blue pipe is only a symptom of a different problem. The blue will not affect operation of the bike but the root cause of the blue needs to be fixed. There are 2 main potential causes to consider: 1) Wrong air/fuel mixture. Remove your spark plug and look at the tip. Very dry and white = too lean, Wet and black = too rich. Too lean,look for air leaks first. Otherwise you will need to fiddle with jetting. 2) Cooling system fault. Fill the radiator, run the bike and wait for the fan to turn on. Shut off, let cool and check fluid level. If level is down it either puked it all over your garage floor or it is leaking internally. Also drain the oil and see if it is milky. If milky water is leaking in - mostly likey water pump seal but could be other things. One polish that will remove bluing from chrme is named Simichrome. Fix the problem first them the blue. Quote Link to comment Share on other sites More sharing options...
jse Posted September 7, 2012 Report Share Posted September 7, 2012 Hi guys, '01 txt 321, seems to be running hot - the exhaust header is turning blue, and it just feels hot, the exhaust and all. Plenty of water in the radiator, and the fan is working. I'm wondering if there is a thermostat that can go bad? (I don't know how to check it...) Can the water pump impeller strip or quit pumping? I recently went to Boyesen reeds - am I running a bit lean? Just looking for some ideas. Jeff Jeff, Boyesens tend to make an engine run slightly rich. Looking at the "latest mods vs. symptoms", I'm guessing that you may have an air leak at the manifold when installing the reeds. The most common cause is overtightening the manifold, which will bow the sealing surface between the bolt holes. I'd take the reedcage and manifold off and use a little sealer on all the sealing surfaces and just snug up the bolts, letting the sealer set overnight (they only go to about 7 Ft Lbs, beyond the range of most common torque wrenches). In addition to the other suggestions, it could be a coincidence, but a clogged/obstructed exhaust will also cause overheating. Jon Quote Link to comment Share on other sites More sharing options...
farmerj Posted September 7, 2012 Author Report Share Posted September 7, 2012 Wow, you guys are awesome - thanks so much! I'll report back my findings! Jeff Quote Link to comment Share on other sites More sharing options...
copemech Posted September 8, 2012 Report Share Posted September 8, 2012 Never worked on one, yet you may chk the ignition timing on the stator plate, as if it has been set back a bit far this can lead to high pipe temps. Quote Link to comment Share on other sites More sharing options...
bricklane Posted September 17, 2012 Report Share Posted September 17, 2012 I would look at the water pump...they tend to snap...you won't know it's broke till the engine gets red hot like you said or the radiator pipe goes bang with the pressure. Quote Link to comment Share on other sites More sharing options...
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