cfmoto v5 overheating

[blackgsx01]

HI

I was hoping to get alittle help with a v5 I am having problems with.

bike overheats when riding at 60mph for about 7-10miles, but if you just cruise at 35-50mph the temp is lower but still kinda high

I replaced the coolant,thermostat, and added redline waterwetter, bleed the system twice, and it hasnt changed a bit, still does the same thing(fan works) and this is on a 70 degree day to.

I have heard of this problem, but cant seem to talk to anyone on what would help.

any ideas?
thank you

[rverr]

BLACKGSX01-Is it actualy over heating or is it just the gauge showing over heating? Is the fan coming on??? KEEP ON SCOOTIN!!!

[blackgsx01]

Yes the fan is coming on, and I switched the gauge also and it still reads the same.

Now even once its in the red, and I stop it doesnt boil or anything like that.

[na1x]

I'm almost sure the gauge is not accurate. Mine was just like yours. I put a 400 ohm 1/4 watt resistor in series with the wire going to the coolant sensor which is mounted in the tstat housing. Works perfect now.
Joe

[rerun2]

Sonds like a bad gauge, you have confirmed that the engine is NOT really overheating, so the problem is obvious, you b getting bad data!!

[blackgsx01]

Ok, so if I put this resistor in then it will make the gauge more accurate? I tried 2 guage's and they both did the same thing, so I don't know the odds of that, but what should be the max temp for these bikes? I was gonna run it and check the temp of the engine and radiator.

[monty57]

You should verify engine temp with an infrared thermometer. I bought mine at Sears ($80) but I have heard Harbor Freight Tools has one for $20. Once you are sure the engine is OK, it sounds like the only thing you haven't changed is the sending unit that sends the signal to the gage. They can cause the meter to give false readings. Also check all the grounds in the circuit just in case.

[blackgsx01]

well I just changed the sending unit......and still gets in the red.....but I just noticed that on the tach 0-55mph is in black...and 60-90mph is in red. So if I push the bike to 60-65mph(red) the temp gauge is in red, but if I ride the bike at 55mph(black) the temp gauge with be at the top of the black reading. Its almost as if the temp gauge follows the tach.


If I run it and then shoot it with a temp gun, what should be a good temp for these bikes, I was going to shoot the engine, theromostat and compare.

[hillbilly]

If it was me I woud get a real temp gauge with degree readings at the auto parts store and tap into a hose at least temporarily to see what the temp really is. Red, black, and whatever on a gauge doesn't do much for me. Adding resistors to make a gauge read what I prefer seems questionable to me if not based on an accurate reference.

[donroketa]

My 250 Roketa Bali acts exactly the same as yours, I have not had much time to check it out yet, even though I have a infared thermometer. It is almost as if the increased speed creates higher charge rate, and the temp gage is indicating the voltage increase at the battery from the higher charge rate. Mine never boils either. I have changed the coolant so far, made only a slight difference, the junk in it was like black ink with sand in it.

[rverr]

8-)While we are on the over heating subject here's is a little hint to prevent air-lock ,when changing thermostat or coolant, If the thermostat does'nt have a check valve or air bleed hole drill a small in the thermostat this will prevent air-lock it works for me. KEEP ON SCOOTIN!!!

[blackgsx01]

well the coolant is boiling.......I confirmed it today.


when It was begged in red, I stopped and hit it with the temp gun.

head-150deg
block-250deg
thermostat-195deg
exhaust-250deg
radiator-180deg

when I shot these, I heard bubbling from the reservoir. The bike sat for about 5min and was back at the halfway mark.

Still think there's air in the system? I was going to drain the coolant again, blow air through the system and see if anything is plugged, restart and fill the system while its running this time.

[brycegtx]

Hello gsx01, look at my post #36 on this thread (last post as of today). scootdawg.proboards59.com/index.cgi?board=200cc&action=display&thread=1183690388&page=2

I also have the CFMoto 244 in my scoot. I assume its the same engine as in yours. Even at over 100 F outside, I have never seen over half way up the temp gauge. Siince you have replaced both gauge and sensor, presumably as you suspect, it is overheating.

The first time I replaced the coolant, I noticed a air pocket in the head. I got rid of it by removing the top hose off the engine while filling to assure the head is full.
Hopefully this helps you,
Bryce

[donroketa]

My gut feeling is still that we have an airlock, I have encountered this on several other gas engines in my time. If I find the culprit, I may just drill and tap the head at the highest point.. Thanks for the infared shot temps, will give me something to compare to. I intend to do the top hose trick first, as well as another that someone suggested that worked for him, that was to lay it over both ways on its side to try to chase air bubbles.

[blackgsx01]

now are we talking about the top hose on the valve cover? the breather hose..........how would that help get the air out of the cooling system???

I was thinking of drilling and tapping into the thermostat housing it self and putting a little bleed screw in it if this doesn't work.

[donroketa]

I was only referring to the previous post, there must be a coolant hose up there somewhere.

[blackgsx01]

well I purged it for an hour today, pulling off the hose from the stat to the carb hoping to get what ever air out of it.........and guess what............it still overheats. I plan on draining the coolant tomorrow and running a flush chemical through the system. I think that maybe its gummed up some were. Also I am gonna check the water pump impeller and see if its not gummed up and slowing the flow down.

[YellowScooter]

Bad water pump maybe? From what I've heard it takes nothing to get these systems gummed up good! And hearing what comes out of these at the initial flush It wouldn't surprise me in the least to see a ruined water pump, thermostat, or both.
My bossman took out his thermostat and wired his cooling fan through a manual switch. He went through 3 thermostats and no longer trusted anymore replacements. It's been about a year since he did that, and he says the gauge always stays well below 1/2 way.

[Jacine]

I'll repost this from the CFMOTO forum.

Hairline micro crack comes to mind, but not sure where yet. If it idles well then temp is controlled crack is closed so no intake of air into the system. If under load, increased pressure, increased circulation, widening of crack (or attachment) air suction intake and overheating with block and overflow. Not likely to be a head gasket, but something on the external setup, rad, hoses, clamps etc. The question is how to reveal a micro fracture. It would have to be on the low pressure side.

[donroketa]

I sure hope you get it figured out, cause I am certain I have the identical problem, and probably the identical solution.
I did the rock it from side to side lay over yesterday, did not do a bit of good.

[kelvincasper]

Hi:

I have a Yamati 250 with a cfmoto 244 engine. It overheated also when i first got it. I found out the girl who sold it to me put in the wrong antifreeze mix. But before I changed it, I went to a auto store and got to flex hoses about 3 inches in diamator and cut them then took some regular house wire hangers and attached the front to the air intake opening and bent it inside the hose to hold it in place. Then i ran them along the sides and put them against the radiator so that additional air would be forced directly through the radiator on each side. This helped me a lot. I was rinding on a 90 degree day around 60 miles and it just got up to a little over half warm. I was going around 60mph. Maybe this will help you.

Kelvin

[donroketa]

Thanks for that. My Bali 250 Roketa looks like the airflow was desgned by an idiot! There is a solid front of plastic in front of the radiator, no way it gets any airflow! I am sure a couple of hole saw holes would "cure" the problem. However, I am not wanting to cover up the real problem by doing that just yet. Something else is wrong, and I want to find that first, then make me some airflow mods.

[kelvincasper]

Hi:

Just wanted to let you know my Yamati is designed the same way your bali and roketa type bikes. My radiator is sort of blocked also. I just installed the flex-hoses to improve the venting of air directly through the radiator and help increase the cooling power. But good luck in trying to hunt down the problem it seems like you have done quite a bit of work so far. It seems that a lot of others are having similar problems. This works well for me. Some fixes require using some of your brain power considering they didn't design it properly in the first place. The radiator should have been put in the front of the bike to get direct air flow. I am just helping it out a little to be more like it should have been done. Also this is some extra protection for if the fan fails. I have also noticed my fan runs at a higher speed when i turn off the headlights Strange! But if i need extra cooling power off the lights go during day riding.


Kelvin

[brycegtx]

I am not sure I see the difference between mounting the radiator in the front. Any air that comes through the front opening now will have to flow past the fuel tank and through the radiator. So what do I gain by putting it in the front? It gets the same amount of air.

I don't want my radiator in front of the gas tank, because I don't want the gas tank heated up by the air going through the radiator.

And I don't want the air deflected down in front of the gas tank (like some scoots), because I want that air to go back and flow across the engine to reduce its temperature. Most of the time, the air going through the radiator is not that hot, so I want that air to flow across the engine and everthing else in back to keep things cool.

So I think the design is correct that way it is.
Bryce

[kelvincasper]

Hi:

I didn't say move the radiator to the front, I said that's where the designers should have put it. I just installed some flex pipe from the front air intake along the side to they touch the front of the radiator, this channels air directly through the front of the radiator thats all which adds additional cooling.

Kelvin

[YellowScooter]

I can't believe the radiator isn't put up front where it can get the oncoming air to begin with... Even rear mounted and mid mounted engined cars have the radiater up front behind the car's grill! Duh!
If it wern't to difficult to do so, thats where I'd be remounting it to. If it's behind any plastic where hole would be benificial, I'd be doing some cutting before I even got the thing all the way outta the crate... If only 250s came air cooled, that would be my 1st choice hands down.....

[brycegtx]

The MC54 does not have a problem with the radiator not cooling and its radiator is mounted behind the fuel tank. We have had the scoot in 110 Degree weather and it never went much above 1/2 way at a continuous 65mph.

The other problem (other than what I have already mentioned) is that the radiator would be mounted directly in back of the front wheel. All the dirt, stones, mud and what-not would be thrown directly at the radiator. Not something I want.

A number of ATVs ,mount the radiator in the back because they get plugged up in the front with mud.

Something to consider,
Bryce

[donroketa]

The deflection of mud and rocks is not a problem, the holes would be up where the front fender would prevent those problems.

[brycegtx]

On an MC54, you would have to mount the bottom of the radiator over half way up the front. The radiator would be mounted just under the triple tree. In that case, there is little room for air outlet of the radiator and there would be a long duct to route the heated air away from the fuel tank. We are now blocking the outlet of the radiator. Then since its so high in the body, other electrical and such might be subjected to additional heat.

Seems to me that if the design is good enough for the Honda Reflex, (since Honda designed it the same way) it is probably good enough for us.
Bryce

[soyjim]

heh all out there. I know there are several people having these overheating problems. I proposed a solution to this overheating problem and I hoped that some people that are comfortable fiddling around with scooters and have the tools would check it out. (see post in250cc section entitled proposed overheating solution. The helix shop manual suggests that a non running continuity check be done on the sensor to gauge circuit when the gauge is reporting an overheating condition. your bike probably uses a similar 15 pin multiconector that my bike has. If the ground wire is in the wrong pin like it was on my bike the manual says that the guage will report an overheated condition because the resistance in the circuit is fouled up due to the lack of grounding. hope this helps you solve this vexing problem. it will be a while before I can get my scoot back together to run the bike to determine if the problem was fixed by making the proper ground connection on the circuit. I really believe this is going to work. I can see where an improperly placed grounding pin in the instumet panel wiring harness could slip thru the chineese supply network and little else would be afected. My bikes intrument panel has some fancy light up displays that wouldn't work without proper grounding but most scoots use something else.

Peace Be with you