help with 99 yz400 been sittn for awhile

dctodd

Member
Aug 19, 2008
4
0
just got a 99 yz400 tried kickn it , saw water drippn out of pipe , took pipe off had water sittn in pipe what should i do now? ill drain oil tomorrow,the bike was sittn outside of previous owners place probly 2 months . please someone help me give me some good news doent know what to do next! i checkd plug when kickn got spark , am i been paranoid and just kick the heck out of it to fire it up?
 

Rich Rohrich

Moderator / BioHazard
LIFETIME SPONSOR
Jul 27, 1999
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Start by checking the obvious things first:

- Change the oil and the filter, and pay attention to the way the oil looks coming out.
- Pull off the carb and clean the jets, including the accelerator pump
-Check the valve clearance.
-Do a compression check, to verify the engine is at least sealing.
-Clean the grounds for the coil.
-Pull the connectors from the stator to the CDI, clean them and reseal them with dielectric grease.
-Put in a new sparkplug.
-Put in fresh fuel.

Once you have verified that you have a basically sound engine, then follow this starting procedure from Doug Dubach, that was originally posted on the Yamaha website.



We offer the most innovative line-up of four-stroke competition motorcycles in the industry. To further enhance the enjoyment of these products, please follow the step-by-step instructions as explained by Doug Dubach, Four-Stroke Motocross Champion and Yamaha test rider. These helpful tips will ensure quick and easy starting of your Yamaha four-stroke motorcycle.

COLD ENGINE STARTING:

1 - Make sure the bike has fuel, then turn on fuel petcock

2 - Pull out choke knob (black knob on left side of the carburetor).

3 - Prime the engine by giving the throttle two full turns (only if the bike has not been started in a day or two).

4 - Apply firm pressure to the kick-starter with your foot until you hit distinct resistance (this is the compression stroke/hard spot).

5 - While keeping pressure on the kick-starter, pull in the compression release lever and push the kick-starter past the compression stroke/hard spot. The kick-starter needs to only move about 1 to 2 inches past the hard spot. That is all!

6 - Release the compression release lever and return the kick-starter to the top

7 - Now, kick to start. Do not touch the throttle, as the engine will start and idle on it's own

8 - If the bike does not start, repeat steps 4 through 7 only until the engine starts.

HOT ENGINE STARTING

1 - Pull out the hot start knob (red knob on the left side of the carburetor).

2 - Follow steps 4 through 7 until engine starts.

3 - You may have to apply some throttle after the engine starts until you get the hot start knob pushed back in because the carburetor is sending a lean mixture while the hot start knob is out.

The only difference between hot and cold starting is which knob you use, choke or hot start. There is no need to deviate from these simple steps. Remember, DO NOT touch the throttle during hot or cold starting. Also, there is no reason to prime the engine again on the same day of riding.
OTHER HELPFUL TIPS
It helps to become comfortable with steps 4 through 7. By becoming familiar with these steps you will become more efficient and will be able to perform them quicker. The faster you can get through steps 4 through 7 the quicker you will get going.
You need to give the engine what it wants! Understand that the choke will give the engine a rich mixture and the hot start will give the engine a lean mixture. If you have kicked the engine several times during a cold starting procedure and it still won't start, maybe it has too much fuel. Don't be afraid to push the choke back in and use the hot start, even though the engine is cold, this will give the engine a lean mixture and that might be just what it wants.
Again, make sure you don't go more than an inch or two past the hard spot when setting up your kick, and return the kick tarter all the way to the top, especially on the 250F. This will ensure that you get a proper kick and make your race day more enjoyable.
 
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