Running premix instaed of pump

[dirtbag]

I bought a 1980 440 Invader last year. The pump had been disconnected (I don't know why). I ran premix last winter and put on about 400 miles with no problem so that center bearing must get some lube when running premix.

I have yet to test the pump. Eventually I will and if it works I wil likely reconnect it.

That said has anyone actually had the center bearing go due to running PM?

Thanks

[jimvw57]

There is no center seal on an Invader motor. he center seal is a labrynth design which uses oil from the injector pump to seal the case. I would assume with putting 400 miles on your sled that the pump is connected and working.

When the motor is idling and slow speeds, the pump puts out a lesser amount. at higher speeds, the output of the pump is increased. premix is a constant percentage and will work, but you could be getting too much at low speeds (causing plugs to foul) or starving at higher speeds (could cause wear damage or overheating)

I have never had an oil pump fail, nor have I personally seen one fail. I guess it could happen, but it is pretty uncommon. Make sure it works and hook it back up.  i prefer not having to mix gas and just keep the oil reservoir full, add gas and go.

[mswyka]

Based upon our experience pump failure is defined as putting too much oil into the engine.  The pump is a rotating barrel pump and is quite exquisite in its simplicity.   The barrel appears to be ceramic coated and will inject oil when the ports in the barrel line up with the outlet ports on the pump housing.  If grit enters the pump it will wear the coating off of the barrel and allow oil to enter the engine all the time.  It is easy to spot this problem because the engine will litteraly drink oil.  The photo attached shows a worn pump barrel.  The two circumferential stripes are grooves that should not be there.

At any rate, if you take the pump apart to check it be sure to remove both gears before attempting to slide out the barrel.  If the barrel is slid out before the bottom gear this gear will score the coating on the barrel.

[Tory944]

   Good info!

[kawhead]

i've seen a few oil pumps lock up and shear the key....very rare....i've seen a few vaders with no oil pump,imo the plastic shields on the inside bearings would concern me most.....most sled cranks use a lab seal with no oil feed.....in theory the oil in the grooves is pushed back and forth by the pressure waves and needs only a small amout added by splash or drip  type lube

[mswyka]

We have purchased, and been given, multiple Kawasaki sleds over the course of the past decade.  After reviewing the information provided with each sled and performing our own forensic analysis we find a fairly familiar theme related to oil management and engine operation.  This is the way we believe it plays out:

1.  Kawasaki sleds are susceptible to crank seal failure. 
2.  The owner either does not know about this or is not willing to believe that this is the case.  They find that they lose compression and then see the top of the piston and the top ring chewed up and assume that there was not enough oil to keep things lubricated.
3.  They don't have a clutch puller and therefore cannot take the engine out of the chassis so they only replace the pistons.
4.  Again assuming a lack of oil they assume oil pump failure and switch to pre-mix only to have the problem repeat itself. 
5.  The sled sits for a year or two or more before it comes to us.  Tearing the engine down the first thing we see is that the crank seals are shot - usually the mag side, but every once in a while the PTO side.

It is a very sad story, but one that seems to repeat itself all too often.  The long and the short of this tale is that we have found the Kawasaki engine and its oil injection system to be extremely reliable.  We have also learned that every engine that we take in needs to be torn down, inspected and rebuilt to factory specification before attempting to use it.  Any time we have been tempted to take short cuts we have had engine failure.  Each time we cover all the bases we build engines that run, and continue to run reliably season after season.

[rminier]

Very well said....Good thread for future newcomers.

[kawhead]

imo mark is right on the     mark   lol 

[Lloyd (ljm)]

 Mark is wise and speaks the truth

[Interceptor398]

I'm in complete agreement!!

[jimvw57]

Similar to the chant Crankseals, crankseals, crankseals

[mswyka]

Similar to the chant Crankseals, crankseals, crankseals

Jim, do we have a pinned item somewhered around here to the effect of "Now that you have acquired your first Kawasaki, STOP, DO NOT PASS GO, DO NOT COLLECT $200, UNTIL ..."

[Boomologist]

Hi all,
Been awhile but Yes, I'm still alive!
Kawasaki oil pumps are great. I have owned over a dozen Kawasaki sleds and have never had an issue with pump failure but like everything else on the sled you must keep dirt out of the system.
Another issue with running pre-mix is the carbs are not sucking straight gas as they were designed to do but a mix of fuel and oil which can cause a lean fuel/air mixture (less gas because some gas is replaced by oil) and we all know that a lean mixture isn't good for the engine.
The oil pump is running in oil and as such is well lubricated. It will be the last part of the sled to wear out provided the system is kept clean.
These engines are a work of science and countless hours went into designing them to be small, light weight and extremely powerful. Any changes to the system will most likely shorten its life or degrade performance.

Incidentally, the oil system puts out about 100:1 at idle and as high as 10:1 under full load.
Ron