I got the air out of it by running it and refilling it a few times. <-- Is that burping it?

Yeah. Just as long as there is no air in the system. (give the radiator hoses a squeeze to make sure) Now what about the temp sensor? (the fan shouldn't be running continuously) and in your picture it's unplugged.

http://i1336.photobucket.com/albums/...ps5ff8908d.png

If the fan is running all the time. You shouldn't be overheating above 45mph.

I would do a radiator pressure/leak test.

http://contentinfo.autozone.com/znet...V4560/image/2/

And a cylinder leak down test also.

http://ecx.images-amazon.com/images/...500_AA300_.jpg

You can rent these from most auto parts store. :)

Why would you do a pressure test on a radiator that he didn't say was leaking?

He said he changed the oil and didn't mention any antifreeze in it so it doesn't have a blown head gasket. Not a stuck thermostat either, if it was the scooter would overheat just idling?

It's very simple, air in the system, the slightest amount will make it overheat especially after it's ran at higher RPM's.

We have a full proof burping how to where you first asked about this scooter and I know it well and before anyone asks, yes I have a scooter with this same exact engine/radiator set up along with two other water cooled scooters including the 250A and 250B with linhais.

JR

As usual JR your tech chops are dead on. (burp the baby) but I'm also thinking that the jury rigged wiring, no temperature sensor, and having the fan on all the time can't be good.

Yes he needs to fix the thermo switch and re-wire the fan but at this point it's not an issue with the over heating. But in the long run it will cause weak battery issues because unlike the other popular 250 engine the linhai this engine's charging system is weaker.

Also it seems that when I ask some questions they seem to get edited? In the above post I asked why would one do a radiator pressure test on a radiator that is not leaking? Makes no sense? Everyone knows if the radiator is leaking eventually the engine will run hot but even then you just fix or replace the radiator, pressure test?

Also if the engine has low compression? This will not cause overheating.

I put the question back in.

JR

By who ??. Only a mod or you can edit your posts.

It will say who did the edit in your post.

It wasn't me. :)

I guess we do things different out here at chasing problems.

Without being there, Nobody really knows whats wrong with it.

did the burp thing and now waiting for a nicer day to test it.

It wasn't me. :)


Didn't say it was?

I guess we do things different out here at chasing problems.


Very different indeed? Man never said or implied it was leaking, pressure tests are for a leaking radiator, compression tests are for engine problems, has nothing to do with it running hot.


Without being there, Nobody really knows what's wrong with i

Don't need to be there unless his information is wrong. By his information he does not have a blown head gasket or a leaking radiator. Air even the slightest amount is a killer on this engine. Thermostat isn't closed or it would heat up in less than 5 minutes.

He hasn't mentioned if he has checked to see if the coolant is circulating. If it is then it's just plain old air......but if he doesn't have coolant circulation, I'll see if the way people check out there know what the problem is? http://www.scootdawg.net/images/icons/duh.gif

JR

That is the sign of a blown head gasket = Steam looking like smoke.

It was getting HOT again.


And you still think its just air in the cooling system ? .

Missed by all including me:

So I thought to check the coolant the reservoir was full but when I looked under the seat I found a hole in the plastic filler.

Loss of power = hot engine.

Steam equal coolant coming or dripping out this hole. If the radiator reservoir has a hole in it not only is it losing coolant slowly when the engine heats up but when it cools and the radiator is pulling fluid back in the radiator there is none there and it's pulling air into the system.

We all know that these systems work just like a auto system, cap expands when hot, pulls extra coolant if needed from the reservoir tank or releases it back to the tank if not needed. As it cools off it makes sure the radiator is topped off to the full amount.

Got to fix this or it's never work right.

JR

Lets all hope, that he didn't cook that motor.

I feel kind of bad for breaking out the bad guy here but I look at it this way, for $700 you just took a really good course in experience so that when in the future you ever experience this kind of behavior in a more expensive vehicle (such as an automobile) you will know that you need to leave it pulled over where you first stopped and call a tow truck, because if you don't you could be looking at replacing an engine that in a car can easily cost you 7 or 8 thousand dollars, so for $700 you got away cheap.

The unfortunate part on these 250's is that, if you did fry the engine, it's going to cost you more than you paid for the vehicle itself, something the seller may or may not have known about. Chances are, if you ask me, he knew something about it but decided to sell it before he got into knowing the full extent of the problem, that's just my opinion but in fact a moot point.

Now I think the engine is all right but you need to address the problem and stop driving it in hopes that it will go away, because it won't. Your problem is likely either a stuck thermostat or possibly a blown head gasket, something along those lines is what I would be checking into.

Personally I would start by replacing the thermostat, because it's cheaper and far easier than the head gasket.
You never know, especially if the scooter still has coolant, that might be all it is.

Good luck

David, Any updates ??.

I am having a similar problem with overheating. I thought that I had burped all of the air out, engine temp. was running normal. The fan was coming on. Twice I let my scooter idle for about 30 minutes and everything was fine. Or so I thought it was until I went out on the interstate. I went only about a mile at around 70 mph. then I exited. The temp guage never went above normal. The fan was running, everything appeared fine. After about another mile on the street, I noticed the temp. guage had red lined HOT. I have NO thermostat installed, I had removed it to eliminate that as a possible problem. So there shouldn;t be anything keeping the collant from circulating. Now, when I pulled over, I noticed that my fan was NO longer coming on. I believe that there is still air in the system, and my interstate ride moved it along.
Because before when I first flushed the system, and then installed the new coolant, when I first started up the scooter, the fan didn't come on because the radiator was cold. Even though the engine was HOT, but the coolant wasn't getting circulated thru the system because of the AIR in the line. As far as the radiator was concered the collant was cool and didn't need the fan. The HOT coolant wasn't being circulated to the radiator. However, after several burps, the fan came on and the temp guage went to normal. The problem that I am having now, is exactly as it was yesterday before I was able to get the darn thing to burp, burp, burp.
So, be sure to burp your baby really really good!