could anything pressurize the cooling system?

[nickxc]

I have been putting head gaskets on all summer. I had my head checked and its perfectly straight. I checked my cylinder decks and everything appears fine. I have been torquing the nuts to 20ftlbs and lately to 22ftlbs just trying to stop this coolant pressurizeing problem I have been having and nothing is working. I was told to try putting yamabond on my headgasket and putting it back in and I think Im gunna try it. I will take an old head gasket and use carb cleaner to strip all the paint. then take yamabond and put it on my finger and put as thin a coat as possible all over both sides of the head gasket. Do you think this is a good idea or is it possible for something else to be pressurizeing the system and causing coolant to come out the overflow....

 

 

PLEASE HELP!!!!!

 

The most I have noticed this is when the motor is good and hot (after running hard) and I let her idle for a couple seconds (long enough to open a gate and push the quad through and then close the gate behind me) Then I hit it WOT up the road hitting gears and I get antifreeze on my let from the overflow tube (its never been hot, always cool)... just fyi...

 

any help please

[Felonious_Monk]

It could be that your radiator is clogged??

 

Maybe check your impellar?? They are plastic, and some say that they can "melt"......Thats the reason for the aluminum ones....??

 

I dont really have an answer for you, because I have not experienced anything like what you describe. But, if I was in your situation, I would look to the impellar, the impellar gear, and then give my radiator a good flush. That is if I was positive that my head surface was within spec, and everything else checked out. There really isn't too much to the cooling systems on our shee's. Just go through the whole system.

 

Just a note. I totally removed the overflow bottle, and all hoses related to it. I have had no problems whatsoever to date. I just check my coolant level more often.

 

Good luck

 

Monk

[sredish]

Definitely a blockage. The antifreeze should burn the shit outta you, like 150 degrees or so. If it's not hot, then it's not flowing through your rad and your going to overheat it and blow it up. Find the blockage, could be the impeller is bad.

[nickxc]

I have a temp guage and its been runnin between 130 degrees and 170 degrees depending on how fast Im going and how hot it is out. I have flushed my rad. and it flows fine. also my rad is always warm and seems to be cooling the motor good. I thought the reason the coolant was cold (comming out of the over flow) was because the pressure was forcing the coolant back into the bottle and the cold coolant from the bottle was flowing from the bottle to the tube and out.

 

With my rad cap off I can see movement in the coolant.... idk this is killing me...

[Felonious_Monk]

I would say again to check your impellar if you are SURE that your radiator is not clogged. I also see that in your sig it says that you have a shaved head. Who shaved it?? Are you 100% sure that it was done correctly. My uncle built this crazy harley chopper......had trouble with the motor from day one.......they tried to trouble shoot for like two years........anyway, it turns out that the machinist bored the cylinder crooked!!!!!! How?? I dont know, needless to say that the guy felt like a total ass, and still apologizes till this day. The point is that sometimes shit goes wrong. Maybe your head was decked crooked?? I dont know.

 

Like I said before, the cooling system is really basic. There are only a few things that can go wrong. I WOULD NOT USE YAMABOND ALONG WITH A HEAD GASKET TO REMEDY YOUR SITUATION. That shit getss messy real quick. Besides, do you want to fix the problem or just contain it????

 

 

Later,

 

Monk

[nickxc]

do you want to fix the problem or just contain it????

 

That is why I havn't done this yet. I want to fix this prob. I had my head checked for warpage at a machine shop and they said it is perfectly fine. I think the machinest who shaved it knew what he was doing he has been in business for a long time and done many many of these heads. That dosn't mean he couldn't make a mistake but thats why I brought it back and they showed me that it was perfectly flat... Idk. I think im gunna try and get an aftermarket head this winter and put it on and see if I still get coolant out the overflow... If I do then that narrows it down to cylinder decking or impellar but The coolant flows good. I did a 45 second burnout on pavement yesterday (cause I just ordered new tires) and my temp guage went right up to 200 and I took off and as the air flowed through the radiator it poored hot air and cooled the motor right down within a mile. so she is flowing good. I think its gotta be cylinder decking or the head, even though they said the head is fine. If I can afford to get an aftermarket head this winter I will narrow it down if it still does it after that... DAMN!!!!

[NYUK]

a small pinhole inside your cylinders could do the same thing,pressurize the water jacket.

[nickxc]

Hey NYUK I talked to the wife last night about putting $200 more into the shee right now and she shot it down like an iraqie helicopter over fort drum... So Im gunna have to wait a couple months and put tires on her car first..

 

by the way what do you mean a pin hole in the cylinders??? like a hole through the sleve into the cooling system???? how can that happen??? Thanks!!

[.]

where in the coolant bottle are you refilling your coolant to? Just a thought but for the first 4 months I had the shee, every time I rode it coolant would come out the overflow. It would piss me off, and after it cooled there would be just a tiny little bit in the overflow, if any.

 

I'd fill it up to inbetween the lines.....and next time I rode.....same thing. Turns out if I put any coolant in the bottle, it'll overflow it and sit back down below the bottom line where it wants to.

 

Just a thought.

 

Are you sure your cylinders are mated up with the bottom end correctly as well? How tight did you make those inside nuts in the front that you cant get to with a torque wrench?

 

Just trying to think of things. Do you have any buddies with banshees? Switch radiator caps and see if thats it, maybe the radiator cap failed

[Minkia38]

yeah - try the cap

 

also run the shee with the cap off, fill her up - top it off - and while it is still running, put the cap back on. This may pressurize system better......

 

you could also have your head O-ringed...... I also had mine done for my stroker, but the guy forgot, so I said screw it

[boonman]

I don't know why I didn't see this sooner. Alright. Nick, I think I machined your head, if I'm not mistaken. If I am mistaken, oh well. Anyways, You mentioned that you can see movement in the radiator with the cap off. THis is good, and can tell you two things at once.

 

#1- You DO NOT have a head gasket leak. Reason why, is that if you did, you would get a faceful of coolant with the cap off and your gaping squirrely eyes peering into the neck....

 

#2- coolant is moving, and the impellar SHOULD be working. However, it may not..... You will have to remove the clutch cover to check. Or, just remove the water pump cover, and have a look see at the impellar.

 

Now, you Don't have a head gasket leak. Stop wasting $20/gasket, and figure out the problem. Where is your overflow bottle? I moved mine to the front, and haven't had a problem since..... As long as coolant is circulating, your temp guage should work. Is that small line off the head perhaps pinched? Anyways, see what else you can come up with. And stop taking the damn head off!!!!!

[Nightrider]

I agree with some of the others,check your cap,as the temp rises,so does pressure and a badly leaking cap wil allow collant to escape as temperatures rise,not to mention your coolant will boil over faster if the cap is no longer pressre rated.It sounds too simple,but I just had a similar experience with my friends cr250 and turned out his cap was bad.

[nickxc]

I'll try and borrow a cap from a friend. I usually dont tough the level in the bottle it is usually in the middle and when I replace head gaskets I just fill the radiator. one time I did have the radiator cap off and everytime I would give it gas the coolant would flow over and then stop when it was just idaling. But that was like 2 or 3 head gaskets ago. Now another thing. It has only done this once since the last head gasket was put on Im gunna see if it keeps doing it or not. also when you take the head off and you have had a leak you can usually see where its leaking cause there is black from the exhause on the cylinder decks... Last time I changed one I couldn't tell where it was leaking but the time before that I could see where it was. I just piled it up yesterday and with 11 stiches in my leg I wont be on it for a couple weeks anyway... but when I get back on Ill see if I can get it to puke coolant again.

 

Thanks for the input guys all help is appreciated!!!

[cgamla]

Hey gents I had the same problem when I first got mine. If your impeller is not working the banshee cooling system will revert back to a siphon type cooling system due to the fact it has no thermostat. Anyways I rode mine for 6 months with a broke impeller drive pin. When I took the cover off the impeller looked fine and when I turned it over the impeller would even move a little. Then I put a little twisting motion on the thing and realized it was not connected to anything and I'm sure when it was trying to pump water it wasn't moving any at all. What happens is that as you run the motor the cylinders and head heat the water to the boiling point and then the hot water and vapor go up to the radiator where it gets cooled and condenses back to coolant. The problem with this comes from the fact that your coolant temp while pressurized is probably running something like the 230's and when you stop and let it idle your cooling system loses the air flow and cooling capacity and the pressure reaches the limit on the cap and blammo your overflow tank is over filled.

Hope this helps . I would hate to see someone else deal with what I did for so long.

[Forcefed]

If you are seeing "black/burnt" spots on the surface of the cylinders when you do a head gasket replacement....then you can pretty much bet the gasket didn`t seal. You had the head checked...what about the deck surface?

 

What about jetting or minor detonation? You mentioned you had the head machined...how much was taken off? What was the comp diff before and after? Did the machinist rechamber the head after removing the material? What was/is the squish tolerance since the machine work?

Many people think decking the Banshee head is a cheap and easy mod....well it is. But if you don`t take the above mentioned factors into consideration, you can end up with a real headache in the long run. The squish clearence, SAR (squish area ratio -->to bore size), MSV (maximum squish velocity) UCCR and CCR ALL need to be in check with each other to avoid potential issues. If the guy is just a machinist, and not a 2-stroke builder....he mat not know any better. All he knows is that the customer wants .030 off the head...bam...done.

 

What about border line octane requirements.......jetting issues....too much timing for the increase in Comp, SAR, and MSV......take a good hard look at things man, and ask some questions in reference to the head work.

 

My .02

Edited September 10, 2004 by Forcefed