I don't know if this is normal, but I have never looked under the plastic on the quad until recently. When I did, my exhaust manifold was a cherry red. This is only after 10-15 minutes of riding. My quad is a 2005 EFI 700. It runs fine, but I'm concerned about the cherry red exhaust. Is this normal? If not, what can I check? I dont' have any intake leaks. I checked that today with carb cleaner and spraying the intake hoses while running. No change.

Thanks
bob

 

Been through any mud?. You could have a partially clogged muffler or spark arrestor. Running anything but 87 octane gas?. Are you running 'name brand', or 'the cheapest I can find'?. Try switching brands. How's the air filter look?, is it clean with good flow?.

 

No, I haven't been through any mud. The air filter is fair, the bike is clean. I use it to work around the house. I had a problem last month where the fuel injection pump went bad. I had to replace the tank/fuel pump. Just prior to replacing it is when I noticed the glowing exhaust. I thought the new fuel pump had something to do with it, but apparently not because it is still getting hot. I know the sensors all control the fuel injection, so there is nothing I can adjust. Any other suggestions? I hate to keep running it like this if it is not normal.

 

I believe its normal I have heard many people also say theirs glowed red also.

 

I have found a few discussions on this, so it seems normal, but no one ever did confirm it was normal. It just worries me that it is getting too hot and I will burn up the valves. But I am leaning more in the direction that it is normal.

 

I have a 2003 700 and have the same issue. I noticed that as the engine got hotter I was hearing what sounded like an exhaust leak. I looked down at the header and noticed that it was cherry red. I assume that the collector gasket is heating up and leaking.

Initially I thought that it was restricted flow because I have benz muffler (2nd muffler to keep quiet) but it still did the same thing when I removed the benz.

This is also indicated of an engine running lean. I may bump up a jet size of two just to be safe. As far as the issue with the EFI model, the computer should correct a lean engine so this is probably normal for the Polaris quads. If anyone had suggestions I am open to listen.

 

I think your temperature sensor is out or malfunctioning. You are not getting good coolant flow. Red heated metal visible during the daylight is going to be over 1000 degrees. Aluminum melts around 1225, you aren't far from melting down a cylinder head or piston. Just my 2 cents worth.

 

Two things will cause a glowing exhaust that I am aware of:
1) Ignition timing retarded - if this happens, the combustion will be incomplete, and raw fuel will dump into the exhaust which is hot enough to complete the combustion, causing more heat, causing more unburnt fuel to burn...
2) Rich fuel:air mixture - again, unburnt fuel hits the exhaust and completes combustion

 

Mine gets hot and has melted the plastic, but it doesn't glow..