Balance shaft elimination tips...

[funbunion]

I have an 87 Starion, and I have the timing assembly off and apart. I have the extra cash to buy the balance shaft eliminator kit from Racetep, but I don't know what this mod entails. Does the shaft have to come out? Should I replace the oil pump since I'm already in there?

 

One of my secondary chain guides broke for the oil pump/balance chain, lodged it's self in the sprocket, and stripped the gear to nubs on the crank.

 

I heard it happen, and killed the engine within two seconds, so I can't imagine any other damage was done to the engine or turbo.

 

Another good plus is that I was in super low rpm when it happened, thank God. There's nothing scarier than hearing a *pop, screeeeeeeam* and losing all oil pressure.

 

Thanks for any help,

 

Chris

[Cobalt60]

Im not an expert on the BSE but I do believe this would be a good time to also replace the oil pump.

[strang3majik]

if the oil pump is good...keep it in there. There like $180, or something stupid, new.

[Dad]

You will need to remove the oil pan to remove the shafts. The oil pump will need to be removed. If it's working fine then you don't have to replace it. You will need an oil pan gasket- oil pump gasket, oil pick up tube o/ring , front timing gaskets and perhaps a valve cover gasket

 

I suggest a 6 pc BSE kit and cam timing kit- that covers eliminating the balance shafts and also replaces all the front timing components.

 

If you get into it and have a question feel free to contact me.

 

330-505-1804

Enginemac1@aol.com

 

 

Dad

[Indiana]

Don't be buying those parts from TEP unless you like to donate to their bank account you can get those everywhere. You need to flush the oil cooler too. As that guide was wearing the material from it has been pumped in your motor and the oil cooler lets heavy particles fall to the bottom and they stay there.

[scott87star]

You don't need to eliminate the balance shafts, they are there for a reason. Lots of guys do of course and are happy with it but I'm happy with balance shafts. Mitsu calls them silent shafts by the way, a better description for what they are there for.

 

Scott

[Cobalt60]

Its commonly considered that an inline 4 cylinder with no balance shafts should not exceed 2.0L. At least, thats how the manufacturers look at it. That said, it does have benefits and many here recommend it. I personally plan on keeping them; I appreciate their function.

 

Despite what you may have heard, "balancing" your motor does not negate the balance shafts purpose. An inline 4 cylinder is simply not a balanced configuration and will have vibrations that only balance shafts can eliminate. But if you do eliminate them, having as many of your motors parts balanced will minimize vibrations.

[pitboss]

^ yeah, you should have your crank rebalanced if your going to yank those balance shafts. Mine were removed when I bought my car and at around 4500 rpm my knock light goes out indicating knock, which pulls your timing down. Tried adding fuel, opening sparg plug gaps and changing fpr. Sensor might be thinking there's knock from all that vibration. Gonna try 92 octane to see if that helps get rid of knock. So yeah, rebalance the crank too. Or just leave them in.

[vbrad511]

It's a crap shoot when you install the BSEK. Some guys have issues with vibration, some don't. I get a VERY slight "hum" between 2600 and 2800 rpms, but I'd do it again if i had to. I've got a bit better oil pressure, and the motor seems more responsive. I didn't flush my motor when I did it, but you do have to drop the pan like DAD said. You'll be amazed at the pile of muck sitting in it. And use ONLY an OEM oring for the pickup tube.

 

Check this link and follow it....

 

http://starquest.i-x.net/viewtopic.php?t=944&sid=9719ab879bf37c0c2b79ac84a3fccb4e

[Cobalt60]

Gonna try 92 octane

 

Dont our cars require 92 octane? Mine says 92 octane or higher by the fuel gauge and by the fuel cap.

[pitboss]

hmm, I don't have those stickers on mine. There is one at the bottom of the cluster shrowd that says to only use unleaded gasoline. I'm not sure 92 octane was even around back then in the mid to late 80's. Could have been... no the only required fuel was unleaded.

[funbunion]

Thanks a lot folks. I really appreciate the help. DAD, I hate Racetep with a passion, so I started looking for the elimination kit at autozone for 50 bucks. Thanks for all the help and tips, I think I'll just save this project for next summer when I pull the engine.

[Indiana]

Almost everyone is now adding balance shafts to their motors no matter if its inline 4, 5 or 6 cyl or more, V6, V8 etc since Mitsubishis patent ran out. I don't know about sizes of different motors but 2.7 toyota motors came out with them in mid 90s, that new 5cyl chevy engine has them and I've seen old tractor motors that had pistons the size of gallon paint cans that was over 50 years old and it had a balance shaft in it.

[Cobalt60]

Yes different engine configurations call for different balance shaft setups. For example, inline 4s use 2 counter rotating balancing shafts, and V6s only use one balance shaft. Some engines are inherently balanced, such as inline 6s, flat 6s, and V12s, and thus do not need balance shafts. Also, large displacement 4cyl especially like balance shafts (a 2.6L is a very large displacement as far as automobile 4cyl). Again, manufacturers generally always put them in 4cyl larger than 2.0L. 2.0L or less is kind of considered optional. For example, the 2.0L Mitsubishi 4G63T does have balance shafts, but the 2.0L Mitsubishi 4B11T does not.

 

At any rate, I doubt any manufacturer today would create a 2.6L 4cyl without balance shafts. If they did, it would be a racing motor, not intended for daily driving.

[Polcat87]

I am in a similar perdiciment.....I am at a crossroad where I keep the shafts, or eliminate them.. I am having my timing set replaced and the mechanic wants to remove the shafts... I have been reading a lot of posts on this and I guess I really need to know what are the Pros/cons to the shafts. Other than the obvious size of the motor. I am really on the fence here. Does the performance gain really out weigh the posibility of a constant vibration?? Is it truely that annoying? Whats the real deal here..? I am ready to odrer some stuff from "Dad's" shop, but I just dont know if the BSEK is going on that order as well. Edited November 18, 2009 by Polcat87

[Cobalt60]

I would say a reason more important than performance is simplicity/reliability. Removing the shafts means that there is one less thing to break. It also results in higher oil pressure (maybe someone else can explain why). Everyone has their own opinion on whether or not its a good idea. Having never driven a Quest with a BSEK I cant really say, I just know how they work and why they were put there and they seem like a good idea to me.

[mikec]

The balance shafts (or "Silent Shafts" as Mitsu calls them) are big round cylinders of metal, with chunks taken out, that spin at twice the crankshaft RPMs. An inline 4 cylinder motor has two pistons going UP together, and two going DOWN together... but unfortunately the "big ends" of the connecting rods are going opposite directions (left-n-right) on those paired pistons. This causes a lateral imbalance. Also, the "throws" of the crankshaft (where the connecting rods attach) are not symmetric: there's one going left, one going right, on opposite ends of the crankshaft. Those masses cause a natural vibration in ALL inline 4 cylinder motions; that vibration occurs twice for each crankshaft revolution. Thus they are called "second order vibrations." Balancing the pistons, rods, etc. (as is done on a high quality engine rebuild) cancels out FIRST order vibrations - making sure the piston motions balance/cancel. No machine shop work (balancing work) can cancel out the second order vibrations... because they are caused by asymmetric motion.

 

The missing chunks make the shafts want to shake/vibrate a lot. By spinning those shafts at twice the crankshaft RPM, and putting one on each side of the crankshaft, they cancel out the second order vibrations leading to a very smooth running engine, befitting a "luxury GT" car.

 

The balance shafts do spin in bearings just like the crankshaft. And if your car ever has oil issues, the balance shafts tend to fail first: they're spinning twice as fast as the crankshaft and one is pretty high up in the engine block where low oil pressure causes problems. What happens is the balance shaft and the bearing lock up (sieze) to each other. Andit so happens that one of those balance shafts also drives your oil pump so suddenly all oil pressure is lost. That is the catastrophic failure that scares folks into removing the balance shafts.

 

When they're removed, you have to do a couple things:

1: install a stubby shaft to drive the oil pump in place of the exhaust side balance shaft.

2: replace the balance shaft bearings with solid rings (no oil holes in them) so the original oil holes don't become a horrible oil leak inside the engine.

 

Because your oil pump no longer has to supply the balance shaft bearings, the rest of the engine will get a little bit more oil volume & pressure. The whole car will have a little more engine buzz to it, especially around 3000 to 3500 RPM where things resonate. Most folks feel it in the shift lever.

 

mike c.

[Polcat87]

So, is the vibration minimal??? Like would it annoy me to the point of driving me crazy?? I guess I am asking if the performance is worth the vibration?

[Dad]

I don't notice any vibration in mine at all and only the flywheel is balanced.

 

I even asked wife if she noticed any vibration. see said not at all.

 

Dad

[DClark3one3]

So thats why my shifter vibrates like a XXX toy. :mad:

[pitboss]

^ yeah, when I pulled my balance shafts without rebalancing the engine, I had a pretty strong buzz that got real bad around 3k rpm. Shortly thereafter I was gretting bad noises off and on and then I traded it for a new Jasper reman. with the BSEK, but with a rebalanced crank. There is no vibration in that engine at all.

[Dad]

Any chance that you guys that had vibration replaced maybe one conn rod without balancing. I have noticed a big difference in weights between engines.

 

 

We would actually weigh the rods and sort them before we recon them

 

http://www.enginemachineservice.com/26rodstack.jpg

[pitboss]

Any chance that you guys that had vibration replaced maybe one conn rod without balancing. I have noticed a big difference in weights between engines.

 

 

We would actually weigh the rods and sort them before we recon them

 

http://www.enginemachineservice.com/26rodstack.jpg

 

In my case, all I did was buy a timing kit with the BSEK included, and redid the timing and pulled out the balance shafts and hammered in that big metal sleeve to close off the oil hole on the upper shaft cavity. Took me 2 days to get everything out and reinstalled and timed and running. Never went into the engine any further than that.

[DClark3one3]

In my case I bought the car with the BSEK already installed. I wish they were still in as I only plan to DD my car.

[NewCONQUESTowner]

^ yeah, you should have your crank rebalanced if your going to yank those balance shafts. Mine were removed when I bought my car and at around 4500 rpm my knock light goes out indicating knock, which pulls your timing down. Tried adding fuel, opening sparg plug gaps and changing fpr. Sensor might be thinking there's knock from all that vibration. Gonna try 92 octane to see if that helps get rid of knock. So yeah, rebalance the crank too. Or just leave them in.

 

I too had a similar problem with my 91 talon tsi... Quite a few people along with the dyno shop told me I had phantom knock and I spent the good part of 2 weeks taking everything apart and slowly putting it all back together with lock washers and locktite to make sure everything was tight and making sure nothing touched and I went to extremes to try and find the "phantom knock", it was still there, after 2 months of trying this and trying that, a friend of mine asked what I thought to be at first a dumb question... You have your balance shafts eliminated dont you... Then it hit me, DUH, so I pulled the motor apart, had the flywheel mated to the crank along with the crank pulley and balanced as one assembily, balanced the piston rod combo, put it all back together, phantom knock was gone. The only thing I can guess is the harmonic distortion inside the motor due to the shafts being gone caused the phantom knock.