Are you guys having, or have you heard of others having, overheating problems with the 2000 Grizzly? What's the solution?

 

I've got a 99 grizzly,and have not had any problems with overheating. I've yet to see one overheat. Is your Grizzly overheating if so under what conditions.

 

Peeps,

Are you actually having problems with a 00 Grizzly, or are you just gathering information.
Provide some details of the probel: where, when, how long, how bad.

I haven't had any overheating problems yet, but highest temp has been about 80°F, another 20-25 to go before we max out here in Kansas this summer. Only problem I have had is hesitation when opening it up after an extended slow ride. I believe it has more to do with the gas in the tank and the fuel line getting to hot (vapor lock?)than the engine actually operating at a high temp. At lest the oil temp light has never come on.

This week I insulated the underside of the gas tank, and insulated the fuel line, hoping to decrease the problem. Had it out today for a slow ride, and used it to pull some 16 ft long logs about 8 inches diameter, so it was mostly slow utlity work. No signs of any problem, but it was only low 50's today, although the problem has appeared on colder days too.

I don't know if I hurt or helped, but anyway..

Yammer_Hummer

 

I have been watching my cousins 99 Griz and it overheated so bad that it melted the sparkplug boot. I've recently bought one with the intention to add the HL Big Bore Kit(670) but we have been working on a solution for this. A guy emailed me of the High Lifter Forum with this exact same problem, not wanting to start and spitting gas out exhaust system, he said the High perf. kit helped and the clitch kit helped in slow riding. He also move the exhaust and intake pipes for the tranny away from the cylinder head. I asked about the oil and the High Lifter additive that helps it stay cool, he tolded me that he uses 5w50 Castrol synthetic amd the additive. I haven't done this yet put I'm going to try all of them and install a fan of the Honda 450s in front of the cylinder head.

 

I appreciate all your help. I am looking to buy an ATV and doing some research. Have heard of a couple of people who have had overheating problems with the Grizz and am concerned myself about the oil cooling vs. water cooling and also the small fan on the Grizz. Was looking at the Sportsman 500 a couple of weeks ago but have now heard of a lot of problems with them so I'm not sure what to buy. I appreciate all of your input.

 

I own a 98 Grizzly,and haven't had any problems with it,not any overheating either.I've pulled trees and done numerous work with it on 70-90 Degree days and never had a problem.Some people on these forums have mentioned the overheating problem but it's the first I've heard of it.

 

I own a 98 Grizzly and have numerious mods on it. And it hasn't never overheated but once at the Marango Swamp ride. And any ATV will overheat there. There are many ways you can fix this problem. 1, If you own a 98 Griz buy the lifter kit for the oil cooler to raise it upward for more wind flow. 2, install a bigger oil cooler fan for more fan rpm's and more air flow and cooling. 3, Make a switch from the thermo switch to turn the fan on automatically. So you can turn it on when you first get on you Griz for faster cool down. 4, you can try a type of synthetic oil for your griz. I choose Castrol for mine which inproves cooling, and heat build up. And you might also think about installing a clutch kit which lowers the engines rpm's and make the engine fun cooler. All this mods WILL make your Griz cooler.

 

Peeps,

It's me again. I have an update for you. I went riding again today. The temperature was back up to mid 70's and sunny. We went on a fairly long slow trail ride, breaking down a new one before the weeds get high. Also, in the afternoon, we headed back to my friend's house. His nephew had just finished a school welding project, which was a "sled" to pull behind a 4-wheeler to smooth out the dirt in a calf roping arena. We had 3 4x4's that took turns seeing how it worked, Suzuki 500 QuadRunner, Polaris 325 Magnum and my Grizzly. The Grizzly was by far the best at pulling. Of course it turned into more of a contest than anything. We wanted more weight so we put on a semi tire and three people. It still pulled, but was working hard. I went ahead and pulled it around for 30 minutes, and did the whole arena.

Not ONCE in all of this did the engine overheat, the OIL TEMP light never came on, and it never showed any symptoms of sputtering after slow riding. One additional thing I did was leave the 2 side covers off. The air flow has to be better, because I felt the hot air when I was riding.

Future modifications I am thinking about if higher temps later this summer start casusing problems again is a larger, higher flow fan to replace the existing cooling fan, or maybe try to find a mounting spot for a second fan to blow air across the engine and away from the underneath of the gas tank.

Yammer_Hummer

 

The only way i can see a grizzly overheating is if you in some kind of desert climate. I have never heard of anyone i know having any problems here in canada. They do run hot in the summer but not to the point where i have read this ridiculeous boiling of the gas thing.
I have 800km's and not a flinch. The dam thing keeps getting better if anything. They are like a chevy. LIKE A ROCK.
Power Power and more Power.

 

Yam8,

My guess is you are referring to my post when you mentioned "ridiculous boiling of the gas thing".

At first I thought it wasn't possible either, but the common term of "vapor lock" is known to many people. A good freind and weekly riding companion first mentioned the idea. His basis was an old car he used to have. It was some type of a Chrysler that had a big-block 440 stuffed into a fairly small car. When the engine got hot, it would hesitate after slow driving. One fix was to insulate the fuel lines.

Gas is much more volatile that water, and has a low flash point. I takes a lower temperature to cause the gas to vaporize. If you look, the fuel line is not very thick, and is up under the left side cover. When the engine is running at operating temperature, and the machine is not moving fast, the heat from the engine tends to stay under the seat because of the cover. Slow movement would imply low engine rpm, which in turn would imply low fuel consumption rate, which would imply slow movement of the fuel through the fuel line, which would imply a good opportunity for the fuel to become warmer than desired. The fuel is fed to the caruretor by gravity, there is no fuel pump. If some of the fuel starts turning to vapor, pockets can be formed in the fuel line. Of course the vapor will try to rise to the highest point and stay there. The presence of the pocket can act almost like a blockage and prevent good flow of the fuel.

The day that I had the worst problem was warm, and I was leading a group of 8 ATV's through a NEW trail, we were clearing and breaking down as we went. Much of the 1.5 hours was 1-2 mph, or stopped. A small amount of gas was coming out the vent tube. I had everyone shut off their engines. When I put the tube up to my ear I heard popping and gurgling like a bubbler in an aquarium. After a few minutes it stopped. At the end of the trail we came back out on a gravel road heading back one rider's house. When I accelerated past 5 mph, the Grizzly started sputtering, coughing and backfiring, and almost wouldn't run. Most everyone else took the opportunity to poke fun at me and the Grizzly, as I would have done. My friend who had the car said to just give it throttle just before it started to sputter, and it should slowly pass through. I did this, and after about .5 miles when I reached about 25 mph, it sputtered one last time and then ran perfect. I gave it full throttle, and quickly hit 60 mph. I did get the last laugh, I beat everyone back to the house.

With this, and the fact that I had no sputtering, no hesitation, no bubbling to be heard from vent tube, and no gas coming from the vent tube AFTER I insulated the underside of the fuel tank and the fuel line, can anyone offer a less RIDICULOUS diagnosis of the problem?

Yammer_Hummer