Oil injecton question

[swedefire]

So i am doing a full rebuild on the invader, should i remove oil injection for the cylinders and just use it for the crankbearings?

The sled has been sitting for 20 years so i dont know if i want rely on that old pump...

What do guys think about the matter..?

[jimvw57]

I'd stick with the pump. They are pretty reliable, even after 20 years

[mswyka]

My opinion is that you should use the pump.  If you doubt the pump, take it apart and check it.  It is a mechanical piston/barrel pump that is very reliable.  There is  another post here where someone asked a similar question.  In reply to that question I posted some photos of the inside of the pump.

If you take the pump apart, be sure to remove the input shaft before taking the pump barrel out.  The pump barrel has a very close tolerance within the body of the pump and is coated to make the outside very slippery.  If you take the barrel out of the pump before removing the input shaft the worm gear on the input shaft will score the coating on the barrel and damage that part of the pump.

Once you have the barrel out of the pump you can easily see if it is in tact or not.  There  is very little that can go wrong inside the pump.  But, if grit has  entered the pump it can damage the barrel and allow oil to leak past and too much oil will enter the cylinders. 

Except for a break in the input shaft, it is my opinion that a bad pump will put in too much oil, not too little.

[Checkmarks]

Using the pump

At idle the motor pumps in oil at a ratio of 120 parts to one.  When the motor is WOT that pump pumps at a ratio of 20 parts of oil to one part of fuel.  From idle to WOT it is a progressive ratio. 

With out the pump using premixed fuel.

If you run your mix 20:1 ratio the motor will be properly lubricated at WOT.  At idle you will be fouling plugs.  To each their own.

[swedefire]

Thanks all!

Ill stick with the pump then...