Toyota Tacoma Forum banner

Low down & dirty 3RZ balance shaft removal questions

14K views 3 replies 2 participants last post by  Mr. Lumberg 
#1 ·
Alright, this may be a newb question to some, but I AM a newb when it comes to balance shafts. I get their purpose, & that they can have bearing issues. This is a swap into an offroad only rig, & a few extra harmonic vibes mean nothing to me.

My question: How many of you are getting away with simply cutting, or removing the chain? No kit, quick & easy? Are there potential issues with a chain tensioner doing this? (my biggest worry, & can't seem to find much info on the balance chain system)

I've searched all over, & only find the subject briefly visited, or referring to LCE's kit. I'm not AGAINST the kit, I'd just like to wait to do it until I get into the engine a little further later on.If it's a quick, open up, have a looksy, remove a chain, let the few pounds of rotating mass turn into a few pounds of static mass, & move on kinda thing, I'll probably have that looksy. :D

Any real experience with this?
 
#2 ·
You could probably get away with it, at least for a while, but remember that anything that increases the vibrations of your engine will decrease its longevity. How much, I can't really say, but notice how LCE recommends the kit for racing only... Increasing its vibration will put more stress on mounts and internal components and will in general shake things loose more quickly. I build turbines for a living, and we supply what is called a Campbell Diagram to our clients that specify "do not dwell" zones, speed ranges where resonances can cause the complete failure of a turbine or compressor wheel if they're operated in for any length of time; resonances can and do cause real damage. That being said, one of the guys on this thread http://www.tacomaworld.com/forum/4-cylinder/64499-3rz-balance-shaft-delete.html did it, but it doesn't sound like his ride was in the best of shape to begin with.
 
#3 ·
This is nowhere near a daily driver stocker. This thing will be beat on harder than most can even fathom.

The balance shafts do dampen engine vibrations, but not harmonics. The engines rotating balance, & harmonic dampening are still handled by a balanced crankshaft, & a standard harmonic dampener. Harmonics can & will cause catastrophic damage, but that task is not handled by the balance shafts. The Balance shafts are there for cancelling out the inherent external vibrations due to the design of an inline 4 cylinder engine. So, yes, it can be harder on mounts, bracketry, etc., but in my case, not nearly as hard on them as the terrain it will be operated on.

That said, my worry is having a balance shaft, which is actually just an unbalanced lobe of steel, spinning in there at 5k RPM constantly, causing premature bearing wear. (Due to having an unblanced chunk of steel spinning in them all of the time) I have read a ton on this engine, & the #1 failure seems to originate with balance shaft bearings. (boosted engines aside).

I noticed nowhere on LCE's site claiming race only, but I do know that blocking off the oil ports, as their kit does, raises the oil pressure. I'd imagine that has as much to do with any limitations as anything.

Not saying I haven't missed something, just presenting it all as I understand it. Removing it doesn't really scare me, I'm just curious if anyone has done it this way?
 
#4 ·
The balance shafts do dampen engine vibrations, but not harmonics.
That's exactly what harmonics are though, vibrations, just at some multiple of the fundamental vibration.

I noticed nowhere on LCE's site claiming race only, but I do know that blocking off the oil ports, as their kit does, raises the oil pressure. I'd imagine that has as much to do with any limitations as anything.
From the LC page on their shaft removal:

"Counter Balance Shaft Removal Kit 3RZ


This kit is designed to eliminate the balance shafts in a 3RZ engine. Used primarily in race applications where the balance shafts are removed. Kit includes new bearings replacement inserts, billet aluminum install driver, and oil squirter to keep the chain properly lubricated. Drill Bit and Tap to plug oil galley."

So yeah, they didn't say race ONLY, but intended for at least. One thing they also provide is an squirter for the chain, though I can't imagine that would be for the chain driving the shafts if you're taking them out... Likely they're assuming a race engine build if you're removing the shafts and want to ensure the timing chain isn't being starved of oil.

Not saying I haven't missed something, just presenting it all as I understand it. Removing it doesn't really scare me, I'm just curious if anyone has done it this way?
Check out that link in my previous. That's exactly how Blount1966 and 05RedTaco did theirs... Just removed the chain. Blount didn't notice anything particularly bad according to his post but 05Red had some serious NVH issues after. Mind you that his was on a Nissan 2.5; maybe it's something in their design.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top