balance shaft elimination kit

[turbo4g63]

what purpose does this exactly serve...i always see the kits on different sites, but never knew what they do

[CHAOS]

link? i dunno wtf ur talking aboot

[awdriver]

This is what happens when your b.shaft belt breaks, it blows out the side of your block. So you take them out. Block off the oil passage and get higher oil pressure out of the deal and a little more vibration. I guess it's one less thing to damage your motor . Some one else might have a better explanation

[turbo4g63]

Originally Posted by CHAOS

link? i dunno wtf ur talking aboot

thats b/c your not a dsm guy

[turbo4g63]

Originally Posted by awdriver

This is what happens when your b.shaft belt breaks, it blows out the side of your block. So you take them out. Block off the oil passage and get higher oil pressure out of the deal and a little more vibration. I guess it's one less thing to damage your motor . Some one else might have a better explanation

that is probably the best response i've ever had on this site....you provided everything i asked w/ a picture...thanks

[PaleDSM]

It allows you to remove the balance shaft related components and seal the necessary oil passages in the block. Damage like seen above is not common. Common damage from a busted bshaft belt is nothing other then vibration unless it gets caught up in the timing belt. Then you will skip time and valves will kiss pistons. Still doesn't usually result in a window.

[awdriver]

what makes windows ? snapped rod?

[Hans_GZP]

Yea, snapped rods make cross drilled blocks. Happens a lot of 420a engines haha.

The main reason for b-shaft removal is to get rid of the possibility of that tiny b-shaft belt from breaking and wiping out your cylinder head by taking the timing belt out with it. B-shafts can seize up in the block as well, but that's pretty rare. I've never seen them go through the block under their own power... they are usually helped by the crank/rod.

You will get higher oil pressure and it may be necessary to port your oil relief valve hole to compensate for that oil pressure. My oil pressure gauge maxxes out at 100 psi at anything over 2500 rpms if my oil is still cold (10w-30). Mine is a fresh engine with new oil pump and b-shafts removed. Too much oil pressure can be bad and cause seals to blow out.

[SuperHatch]

If you're wondering the causes of a b-shaft seizing, just think of this...

The B-shafts spin at 2x the crank RPM. Meaning at 7,500RPM, your b-shaft is spinning at 15,000RPM. That puts a lot of stress on the b-shaft bearings.

The front b-shaft is driven off of the small belt that everyone keeps mentioning. That belt is only about 1/2" wide. The tension is set manually and can be set incorrectly pretty easily if you don't know what you're doing. The front b-shaft is lubricated off of the front main oil galley through a small hole in the bearing. If you were to remove the front b-shaft those holes would essentially form an internal oil leak in the motor. A b-shaft elimination kit includes two bearings for the front of the motor that either do not have holes (to cover the leak spot) or two new bearings with holes (that you install 90* out to block the hole).

The rear balance shaft is driven off of the oil pump driven gear. It only has one bearing at the tail end since the front end is supported by the oil pump. The bearings for the rear shaft have no holes form the factory, since the oil for the rear shaft is pumped through the shaft and into the bearing. The balance shaft elimination kit should include a stubby shaft to replace the rear balance shaft, that way that oil pump gear still has something supporting it. The rear b-shaft bearing can stay there since it doesn't serve any purpose anymore.

The b-shaft elimination kit will also include a plug to block the hole where the front b-shaft used to pass through the oil pump casing, this is to prevent a leak. The plug and the stubby shaft are OEM parts off of the lower displacement non-turbo 4G series motors that came from the factory without balance shafts.

Some shops use the rear balance shaft instead of the stubby shaft. They put the shaft on a lathe and turn it down so the weights are not there anymore. They claim that doing this gives more support for the oil pump gears since it is supported by that other bearing still. That's debateable...

A properly balanced rotating assembly without balance shafts will exibit some more vibration that a stock motor, but not tremendous. Do yourself a favor on assembly though and use some high temp loctite on whatever bolts you can.

Ok, done writing for now...

[SuperHatch]

I should add that my "front" and "rear" b-shaft distinctions apply to a DSM motor when installe din the vehicle. On an Evo, since the motor sits opposite, the oil pump driven shaft is in the front and the other shaft is in the rear.

[enigma]

It really a peice of mind kinda mod, but i definitly reccomend it, i have another 4g sitting in my garage that got killed by a broken balance shaft belt.
Oh, i have the tool to install the bearings, just PM me.