• Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

The Oil Delete Thread

B

Burn Down

Well-known member
Dec 22, 2008
508
237
43
Boise Idaho
Nice write up, we did this to the old 900 cranks when we dumped the oil injection. the difference was we drilled the top case half at about a 45* to the gear on the water pump. this would let the oil run down into the water pump cavity from the top. there has to be some cross circulation past the bearing or the oil would just build up and the ones with the delete kit would burn down in a few rides. just not enough to sustain the need on one side or the other.

This is also how speedwerx does there mod engines...
 

KMMAC

Well-known member
Lifetime Membership
Feb 7, 2008
1,461
207
63
Mount Vernon, WA
Is delete being perfomed to save weight and or to improve reliabilty? The reason I ask is I'm looking at a couple sleds setup this way and am curious as to whether or not there is an issue with the oil pumps failing or just a weight mod. Sleds are a 900 and 1000.
 
S

snowmobiler

Well-known member
Nov 26, 2001
8,107
3,922
113
you cant get a drill lined up straight on the mag side with engine in sled.so i guess ill do the oil in the tube thing or zerk.
 
9

907riders.com

Well-known member
Mar 23, 2009
410
118
43
Wasilla, AK
www.907riders.com
This issue was dealt with by the Arctic Race department back in 03-04 if I remember correctly... The was a bulletin on it... I will dig into my old paper work and see if I can find it..

As I recall we had to add a grease zert to the end cap and hit it a couple of time a season.
 

m8magicandmystery

Well-known member
Lifetime Membership
Jan 20, 2008
7,786
3,724
113
Yukon
Question for the guys who are keeping the hose in place and not drilling the case: how much oil are you adding and how often?

well thats a good question...lol...like stated earlier i can put an endless amount in one filling if i want...my hose comes up mag side and is attached a little higher then ypipe hiegth..i remove the plug and start filling and the oil fills the whole hose length then slowly seeps (about 2 to 4 minutes) out of site and i can do this time after time...then the engines smokes like crazy cause the crankcase filled...so to prevent all that and still provide protection i just fill the hose right up once and let it seep down to whatever..and just do that every ride or two..i did not use the one way flow banjo fitting..i used the thru flow on the bottom of the case and i plug the top of the hose ...i never had any issues with the stock delete...!!!...i just did this for a piece of mind because the hose filling will leave enough in the pump drive cavity to satisfy lube requirements as the cavity does retain oil..
 
Last edited:
1

1100Cat

Well-known member
Nov 29, 2007
1,107
56
48
51
Still no explanation as where the oil that mine and m8magic&mystery is going, as explained can put tons in. When done so on start up smokes like a mofo so it has to be getting in somehow. Anyone know for sure?
 
J

JHG

Well-known member
Jan 29, 2008
2,437
519
113
Elizabeth, CO/Bozeman, MT
Still no explanation as where the oil that mine and m8magic&mystery is going, as explained can put tons in. When done so on start up smokes like a mofo so it has to be getting in somehow. Anyone know for sure?

Sorry I can't explain it because in this motor there is no way it can happen. The only explanation would be if your motor had different shields on the inner crank bearings that would allow oil to pass through or the rings that seal up this "cavity" are bad or misaligned. Sorry I don't have a better answer for you.
 
N

Nubulin

Well-known member
Oct 26, 2005
848
206
43
Flatlands USA :(
Forgive my ignorance here....

But are the crank bearings oil tight? it would seem to me that a regular bearing would leak oil through the bearing race.
 

m8magicandmystery

Well-known member
Lifetime Membership
Jan 20, 2008
7,786
3,724
113
Yukon
Sorry I can't explain it because in this motor there is no way it can happen. The only explanation would be if your motor had different shields on the inner crank bearings that would allow oil to pass through or the rings that seal up this "cavity" are bad or misaligned. Sorry I don't have a better answer for you.

hmmm...well if you have a few moments just hook up a hose to the original feed to cavity and see if the oil seeps or not..then all the issues are checked out...we have something different if your oil in line doesn;t seep..:beer; but if the oil seeps in yours we will all chip in for a pair of glasses for ya..:present:
 
S
Nov 26, 2007
454
142
43
Ok I will take a stab at this. The ring, middle crank seal does not make a perfect seal. The ring will let a little gas, oil and air past it. This is why you can keep filling the hose and the oil just bleeds into the crankcase, because a metal ring on a metal surface does not make a tight seal. Just like a piston ring will leak air by it when you do a leak down test on a motor. Not a perfect seal. Running a line from the bottom of the case to the water pump shaft chamber worked good on the older upright twins, but not so well on the laydown twins. Why I dont know. I just know it does not work out as well on they laydown motors. As I have seen problems when this has been done on the laydown motors. Maybe they enough more efficient that you dont get the transfer like on the uprights.

On the old thundercats there was no ports for lubricating the counterbalance shaft. Cat figured there was enough oil and gas that got by the ring (crank seal) to properly lube the counterbalance shaft. It did supply some lube but not enough as a lot of us found out and had to install a grease fitting in the case to oil the counterbalance shaft bearings.


I will have a sled at my shop on Tuesday that has the cover drilled and a grease zerk installed to oil or grease (which ever you prefer) the water pump shaft. The housing behind the cover also needs to be drilled. If I get time I will pull it apart and take some pictures for you guys. This motor in this sled has never had an oil injection system on it, just the zerk and a block off plate. Sled has never had any cranks issues with over 4500 miles on it.

Just my .02
 
J

JHG

Well-known member
Jan 29, 2008
2,437
519
113
Elizabeth, CO/Bozeman, MT
Forgive my ignorance here....

But are the crank bearings oil tight? it would seem to me that a regular bearing would leak oil through the bearing race.

The bearings are not just a regular shielded bearing, they are four journal or roller bearings but the inner bearings have a metal shield that seals to the case preventing the unmixed oil that is injected by the pump to the water pump shaft from leaking out into the case. If this shield leaks then the oil/fuel mix would be altered in the case by the "pure" oil being injected into the case leaking out.

the crank still turns in the seal so its not absolutely sealed off and under heat the oil can seep through. especially with compression and vacuum in the crank case.

This is possible where the crank goes through the seal at the center of the seal but they way people are talking about oil pouring into the cases and smoking does not sound like a seeping issue, it sounds like a leaking or flowing issue. I guess if guy are injecting a ton(like 8+ oz.s) of oil into the case then they maybe getting oil passing into the PTO and MAG side of the case.

hmmm...well if you have a few moments just hook up a hose to the original feed to cavity and see if the oil seeps or not..then all the issues are checked out...we have something different if your oil in line doesn;t seep..:beer; but if the oil seeps in yours we will all chip in for a pair of glasses for ya..:present:

I wish you would have asked this yesterday before the motor went back together. To late now, maybe on the next one.
 
J

JHG

Well-known member
Jan 29, 2008
2,437
519
113
Elizabeth, CO/Bozeman, MT
Running a line from the bottom of the case to the water pump shaft chamber worked good on the older upright twins, but not so well on the laydown twins. Why I dont know. I just know it does not work out as well on they laydown motors. As I have seen problems when this has been done on the laydown motors. Maybe they enough more efficient that you dont get the transfer like on the uprights.

I'm guessing that since the center cavity is somewhat sealed from the mag and pto sides of the case that there isn't enough vacuum to pull the premix in from the case. I was hoping that the water pump shaft spinning would create enough vacuum to transfer the fluid but I had my doubts that it would. I'm planning to run it on a stand and look for fluid transfer, if it doesn't work then I guess we'll look for another approach.

I will have a sled at my shop on Tuesday that has the cover drilled and a grease zerk installed to oil or grease (which ever you prefer) the water pump shaft. The housing behind the cover also needs to be drilled. If I get time I will pull it apart and take some pictures for you guys. This motor in this sled has never had an oil injection system on it, just the zerk and a block off plate.

So are the zerk fittings going on the block off plate where the oil pump used to be? If so, how are you supporting the pump shaft with out a BDX style bushing and how is grease or oil getting to the bearing on the opposite side of the case? The bearing that is behind the water pump itself.

Or am I not following you right at all?
 

m8magicandmystery

Well-known member
Lifetime Membership
Jan 20, 2008
7,786
3,724
113
Yukon
I'm guessing that since the center cavity is somewhat sealed from the mag and pto sides of the case that there isn't enough vacuum to pull the premix in from the case. I was hoping that the water pump shaft spinning would create enough vacuum to transfer the fluid but I had my doubts that it would. I'm planning to run it on a stand and look for fluid transfer, if it doesn't work then I guess we'll look for another approach.

ah ha...you just might have the opportunity to try the hose seepage yet:beer;



So are the zerk fittings going on the block off plate where the oil pump used to be? If so, how are you supporting the pump shaft with out a BDX style bushing and how is grease or oil getting to the bearing on the opposite side of the case? The bearing that is behind the water pump itself.

Or am I not following you right at all?

why wouldn;t a grease zerk work in the original crankcase feed where the bottom banjo went..???.i wouldn;t worry about the top as its an oilite bushing
 
S
Nov 26, 2007
454
142
43
You have to drill a hole through this piece #3 in this picture so you can get oil or grease into the chamber. You are doing the same thing as just adding oil through the hole in the bottom of the water pump chamber. Just getting there through a different spot.
shaftretainer.gif
 

m8magicandmystery

Well-known member
Lifetime Membership
Jan 20, 2008
7,786
3,724
113
Yukon
If this shield leaks then the oil/fuel mix would be altered in the case by the "pure" oil being injected into the case leaking out.
.

with the stock injection system fluctuating from 24 to 1 to 50 to 1 i don;t think this minor amount of pure oil is a factor or consideration with a premix at a constant...they had to assume seepage because they feed this with the stock injection system...if there was no seepage they would have just filled and sealed...but why all the trouble of feed tube and steady flow and supply with the stock system if the didn;t expect a need for replenishing..??
 
Last edited:
S
Nov 26, 2007
454
142
43
why wouldn;t a grease zerk work in the original crankcase feed where the bottom banjo went..???.i wouldn;t worry about the top as its an oilite bushing

This is what I do know. I just install a grease fitting in the hole where the banjo fitting went. Drill a hole through the belly pan so I can get on the zerk with a grease gun. Tip the sled on its side every few rides and give it a shot of grease.
 
Premium Features