| Author | Message | ||
     Drawkward |
All, I've been having what I think is an issue. Some mornings I've been noticing my bike getting to around 165degF going to work. At a stoplight on the way I've seen the coolant temp spike up to 205degf and then go back down to 190 or so once I rev the bike. When I get going again the bike drops back down to the 160s. It may happen again on the way to work. Coming home it doesn't usually happen but it has. I figured I had some air trapped. So I decided to burp the coolant system. What a mess! I've done this a few years ago with no problems following the manual. This time, as the temp neared 155 the coolant started to boil and overflow violently. When I turned the bike off it was like a geyser spraying out of the filler neck. What the hell am I doing wrong? Is there something that is likely broken? I'm lost. | ||
| Willmrx |
The thermostat maybe sticking, the radiators my be restricted with bugs and crud or something is wrong with the water pump impeller. At 155 degrees the cooling fans would not come on yet, How many miles on the bike? | ||
| Nuts4mc |
liquids expand when heated...(watch your wife cook noodles for spaghetti...good cooks don't fill the pot to the top with water)...don't start out with an over filled cooling system and expect it to "contain" itself...the cooling system has only only 3 qts of capacity...out here in the extreme southwest I run straight water and some trick coolant additive...I'm lucky to keep it under 190 in traffic suggest with cooled off bike...you drain the system ...then fill it with 2 qts of coolant ...leave the radiator cap off and start the bike...as the bike warms up the thermostat will open and add some coolant till it barely overflows...tighten down the radiator cap and shut the bike off...add the remaining coolant to the overflow tank and go for a ride...let the bike completely cool off and check the level of the coolant in the over flow tank...adjust the level in the tank with coolant as req'd....since it's cool you can check the level of coolant in the filler neck by opening the radiator cap...it should be at the very top. hope this helps btw the coolant additive I use is this stuff from Justice Brothers ( P/N RC/22P) been only able to find it on Ebay from a Salt Lake City speed shop. https://www.justicebrothers.com/products_carcare_r adiator_additives.htm | ||
| Drawkward |
The bike has 12900 miles. I think the impeller is still working because when I Rev the bike at certain times I can tell that it is circulating the coolant. I know that's not foolproof but it's all I can go on. A bad thermostat stuck shut would only allow a small amount of coolant pass, causing the engine to continue to dump heat into the coolant. Correct? At what point is the engine coolant temperature sensor? Before or after the thermostat as it relates to the radiators being after the thermostat. I guess I could pull the thermostat and see if it's bad somehow, right? Nuts: I wouldn't have expected this violent of a reaction, it was seriously like a volcano. Definitely boiling hot. Like I said I've done this before, twice actually and this never happened. I used to live in Houston and use this bike as a daily and a track day bike. I had water wetter and water in it during that time. After moving back home to Pittsburgh I went back to antifreeze. | ||
| Nuts4mc |
Drawkward...sounds like you know what you're doin... here's link to an old post on T-Stat issues: http://badweatherbikers.com/buell/messages/290431/ 515343.html?1258578491 1) Temp sensor is in front Cyl head 2)Thermostat is in it's own hsg above water pump connected by hoses 3) ...you can test your T-stat in a pan of water...start off cool and warm up the water the T-stat should open... my '08 Parts book shows T-stat and Hsg as (1) part number (Q0222.1AMA)...may be kinda costly...might want to take the T-stat to a rice burner shop and see if the parts guy can cross to a replacement...hope this helps | ||
| Drawkward |
Thank you Nuts. I don't have the parts book so I'm lost from time to time on that front. I wish I knew more about coolant systems in these motorcycles. I was just so surprised when the coolant started geysering out of the rad. It never did that before. I had the typical overflow that the manual describes but never anything like this. I was luck I wasn't standing over it when it happened. So you think I could drop the thermostat in a pot and bring the heat up and actually watch the valve? I'll be trying that out for sure. | ||
| Nuts4mc |
Dward...youtube has many examples: https://www.youtube.com/watch?v=OJkFkdBQcGE most automotive T-stats are "wax pellet" type with a small canister of wax that melts and opens the valve...in my post above with the the link..Zac claims it's bi-metal type which means the temp causes apiece of metal to change shapes and open the valve...either way a pot of boiling water should give you an indication if the T-Stat is opening...also in the link note JimDs description of his T-Stat/engine interaction...might be a clue to help diagnose your issues...good luck | ||
| Stevel |
This is a pretty common issue on many motors. It is normally caused by air/steam pockets formed within the cooling system. Very often these are anticipated during system design on industrial engines and steam riser lines are built into the system. These pockets of gas can cause real damage by overheating if not resolved. Water pumps are designed to pump water not air. The most common solution for this real PIA of a problem is bleeding the air by creating leaks when filling the system by lifting hoses. | ||
| Drawkward |
Steve, Do you think I could do the "Easy Coolant Flush" that just requires you to pull the right radiator inlet hose and let it drain to a bucket while you constantly feed water into the system? Or do you think I'd still need to "search" out the air pockets? I guess it can't hurt to do it. Hopefully I'll have time tonight. I just had another huge problem erupt on my other Buell...not a good week for me and Buell. | ||
| Stevel |
Jonathan, I'm not there, so it's hard to say where the air pockets are, but your pump must see only water or no flow occurs. If there is flow, the flow usually washes the air back to the radiator high side. So the first place I would burp would be the pump inlet and then work from there. | ||
| Skntpig |
How long do you let it run with the cap off when burping it? I found I needed to let it run for 25-30 minutes before bubbles quit coming out. | ||
| Drawkward |
I just tried it again at this time it got to about 162 before it started boiling like crazy. Prior to this I did the "easy coolant flush" and did it until the water ran clear. I'm perplexed. I'm in the process of taking off the thermostat right now. Not the most spacey place in the bike that's for sure. | ||
| Stimbrell |
Hate to say it but sounds like a possible head gasket failure and the cooling system is being pressurised. | ||
| Drawkward |
Geez, Stimbrell, that's a hell of a post to wake up to! I'm not experiencing any of the other symptoms of a head gasket failure. When I did the flush yesterday I got about 3 quarts of yellow out before it started to run clear indicating that I'm not losing coolant. And apart from the occasional spike in temperature around 200deg I'm not seeing any really high temps, even on hot days. Frankly, I should have never even tried to burp the system. I feel like I've opened a can of worms, but I guess it is better to be safe than sorry. I wasn't able to get the thermostat out last night because my almost 2 year old son was literally getting into everything in the garage (he likes to try and put random bolts in the muffler of my CBR F4). I'll try again tonight. I should be getting the new thermostat on Friday. | ||
| Nm5150 |
When I switch form water wetter to coolant and back I let the bike warm up and loosen the bottom bolt on the water pump and start pouring whatever I am changing to in the radiator until it comes out of the water pump for a while and then tighten the bolt back up.Then I let it cool and check the levels. | ||
| Drawkward |
Thermostat worked fine. I put it in water, heated it up with a thermometer in there and watched it open. I'm going to put everything back together and fill the system and try to burp it again. My rad cap seal is going bad though and tore so hopefully I can find one of those somewhere... | ||
| Drawkward |
Might be premature but whatever I did it worked. No more boiling or anything. Come ~170 the bubbles gently came out of the filler neck and I had no issues. Going on about 15 minutes now with good Temps. Spiked at ~174, fans on and thermostat apparently open the temp dropped to ~164 and is very slowly climbing back up. Very small bubbles still escaping. My guess is that the coolant overflow ran dry and introduced too much air to burp. In the process of removing the thermostat I must have evacuated some of the trapped air or something along those lines. My takeaway is, assuming the overflow was dry, don't let that happen! Time will tell. I'll update in a week or so. Thank you all for the advice. | ||
| Drawkward |
Quick update: I took it for a 15 minute jaunt around the town and it behaves as I would expect it to behave now. It no longer has erratic temperature swings. It got up to ~172 and stayed there for a bit. Then by the time I got home it had climbed to ~181 and went up and down from there based on throttle and speed. I have two 30 minute commutes tomorrow so I'll know more but I'm guessing the culprit was air in the system for sure. Enough that even burping didn't help. It is possible that the thermostat was a little stuck I suppose but I'll deal with that if it crops up. For now I have a brand new thermostat still in the box just in case. | ||
| Nuts4mc |
glad to hear she's behaving ...pay attention to your "ambient" (current air temp) temperature...my day time (air) temps can make some major changes (called micro climates) here in the canyons and mountains...it directly affects my my CT....enjoy the riding season! | ||
| Drawkward |
During the ~25 minute commute this morning the CT stayed steady between 175 and 185 with no big swings at a stop or upon acceleration. Definitely an air related issue and most likely my fault for not checking the coolant overflow reservoir. I've relocated my ambient sensor to my airbox. It supposedly gives a more accurate reading of the actual air temp as opposed to the temperature of the air blowing off the fans. I've never been able to tell a difference. |
