yzf 400 head pipe glowing red

yzf 400 over heating immediately as fired up. timming is ok, valve clearnces ok, carb is clean, help please. could it be blown head gasket?

Do a search using "glow" or "glowing" as the search word. You will find hours a reading!

My YZ250f was doing it and I checked valves, timing, cleaned the carb with carb cleaner, blew thru each of the jets, etc. . . It was only red hot while idling and/or very low throttle. Was not lean while riding 1/2 throttle to WOT.

Ended up taking the carb apart again. There was a tiny piece of dirt stuck in the pilot jet. Got it out and problem was resolved.

YMMV

Perhaps 'Glowing Red Pipe' should be 'stickied'....

now i have oil pouring out the small hole on the right side of the head.

now i have oil pouring out the small hole on the right side of the head.

There is no oil behind that hole. It is a 'weep hole' to allow water out of the spark plug well.

If you've got enough fluid in that cavity for it to be "pouring out" you may need to look at plugging the weep hole when you're washing your bike, or being a bit more careful with your hose/pressure washer.

i know that there should'nt be any oil its because its a hole to the spark plug... so do you think the head has a crack? after a minute or so u can see a lot of oil coming out

It may also be the valve cover gasket is bad and weeping down the spark plug cavity.

It may also be the valve cover gasket is bad and weeping down the spark plug cavity.

That's an idea, and easily fixed if so.:moon:

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now