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Balance Shaft Question

Glover45

Probationary Member
14
0
Feb 15, 2015
Jones, Oklahoma
Hey guys, my balance shaft (the one driven by it's own belt) on my 90 eclipse gsx has gone out and I'm wondering how hard it is to fix or if I should just get rid of the belt that drives it or what. Any comments are welcome! Thanks, appreciate it!
 

19Eclipse90

DSM Wiseman
5,278
1,145
Sep 29, 2003
OKC, Oklahoma
What do you mean it's "gone out"? The bearings? Or the belt broke? How did you arrive at that conclusion?

The front balance shaft is just that, a shaft. In and of itself, it won't simply "go out".
 

Glover45

Probationary Member
14
0
Feb 15, 2015
Jones, Oklahoma
T
What do you mean it's "gone out"? The bearings? Or the belt broke? How did you arrive at that conclusion?

The front balance shaft is just that, a shaft. In and of itself, it won't simply "go out".
The bearing has gone out I believe. The pulley is lose as in I can move it in and out but the bolt bolting it to the shaft is loose and it is leaking oil out from behind it and it's making a terrible noise. They both started at the exact same time and that noise sounds like it's coming from high around that shaft. I originally drained the oil thinking that noise was a rod bearing going bad and checked for shavings and the oil was clean so it's not that. So I pulled the timing cover off and started checking pulleys and that's when I came across all this.
 

19Eclipse90

DSM Wiseman
5,278
1,145
Sep 29, 2003
OKC, Oklahoma
The pulley? Or the sprocket? The sprocket bolts to the shaft. The pulley is the tensioner.

If the bolt for the sprocket is loose, that could be all of your troubles. When a/the bearing(s) go out for the shaft, you'll get shavings in the oil just like a connecting rod bearing.

There is no "quick fix" here if it isn't just loose and if you don't already have the parts to do so. Even then it isn't exactly a quick job. I would suggest tightening the bolt on the shaft and recheck for in and out play on the shaft. If there isn't any, spin the shaft by hand to ensure it turns freely. If there is play, I would suggest replacing the bearings and then do whatever you will with the balance shaft -- keep it, delete it, or leave it in place but don't use it. The last two options require the use of a turned down rear shaft or stubby shaft. As well, without the right tools, any way you slice it this job will be extremely difficult with the engine still in the car.
 

Glover45

Probationary Member
14
0
Feb 15, 2015
Jones, Oklahoma
The pulley? Or the sprocket? The sprocket bolts to the shaft. The pulley is the tensioner.

If the bolt for the sprocket is loose, that could be all of your troubles. When a/the bearing(s) go out for the shaft, you'll get shavings in the oil just like a connecting rod bearing.

There is no "quick fix" here if it isn't just loose and if you don't already have the parts to do so. Even then it isn't exactly a quick job. I would suggest tightening the bolt on the shaft and recheck for in and out play on the shaft. If there isn't any, spin the shaft by hand to ensure it turns freely. If there is play, I would suggest replacing the bearings and then do whatever you will with the balance shaft -- keep it, delete it, or leave it in place but don't use it. The last two options require the use of a turned down rear shaft or stubby shaft. As well, without the right tools, any way you slice this job will be extremely difficult with the engine still in the car.
Sorry I should've been more specific. Not sure why I called it a pulley haha but yes the sprocket is what's loose and were the oil leak is coming from I already checked the tightness of the bolt going into it and it is tight and there's still a little play in it which would lead me to believe it's a bearing. It will pull out in push in with about 1/8in play. Is there anyway I could replace the seal behind sprocket to stop the leak and leave the sprocket in and just take the belt off to get by for a little while or would that be a terrble idea?
 

19Eclipse90

DSM Wiseman
5,278
1,145
Sep 29, 2003
OKC, Oklahoma
The reason that isn't a great idea is that you still have the rear balance shaft in place that will be rotating twice as fast as the crankshaft. The two shafts work together. I wouldn't do it so I certainly won't recommend it.
 
Last edited:

CrackedDSM

10+ Year Contributor
2,177
821
Dec 17, 2009
Pensacola, Florida
Park it, pull the rear balance shaft, cut it and weld the hole that it leaves, remove that front balance shaft entirely and seal up the hole...good to go. Don't forget to flip the bearing 180* out too. You can use the front balance shaft turned around to knock the bearings out/back in.
 

boost97gst

Proven Member
3,033
133
Apr 2, 2012
st jacob, Illinois
I would do a rear BS delete only. Just leave the front BS in, obviously don't put the belt on it..... Just let it be in there.
If you like your oil pressure as it sits then you can do a rear delete, keep the front, and have exactly the same oil pressure. You're not clocking the bearings and blocking oil passages so no need to port the oil filter housing or anything. If you DO delete both, like a lot of people do, then check oil pressure for sure. Will most likely be too high.

Good luck.
 

CrackedDSM

10+ Year Contributor
2,177
821
Dec 17, 2009
Pensacola, Florida
If your oil pressure is too high from the bs delete, extremepsi sells the oil filter house pressure relief spring that is from the mirage(same thing as where the OEM stubby shaft is from), that totally alleviates the oil pressure issue. It's like $2-$5 if I can recall correctly.


Edit: Found the little bugger. $5.95 from ExtremePSI.

http://www.extremepsi.com/store/product.php?productid=28635
 

boost97gst

Proven Member
3,033
133
Apr 2, 2012
st jacob, Illinois
^^ There ya go. I haven't experienced it first hand but a different spring for the press. relief makes sense. I guess its either that or porting the relief valve, correct?
I JUST did my first front case and deleted rear, kept front. 5lbs of extra weight and keeping my oil pressure exactly the same as it was? it worked for me but i completely understand why people take both out while they're in there.
Good info Cracked. Thanks
 

pauleyman

DSM Wiseman
8,300
2,847
Nov 19, 2011
oklahoma city, Oklahoma
The main problem I see here is you believe the front balance shaft bearings are toast. If that is the case then you must repair or delete that shaft. Simply runing with no belt wont do. The bearings are fed oil just like the crank and rods. Just because its not turning with no belt doesnt mean it isnt a big issue. At the very least you need to find out for sure. If it were my car the minimum is to at least drop the pan and the front case and then decide what to do from there.
 

donniekak

DSM Wiseman
5,623
973
Mar 23, 2008
Surprise, Arizona
If the front bearing journals are damaged, the only way to salvage the block is the pull the access plugs from the block, and tap the oil galleys to the balance shafts for plugs.
 

BogusSVO

Proven Member
5,891
310
Jul 1, 2009
Pensacola, Florida
How much torque applied to to the BS is immaterial to the BS bearing. It is not a preload bearing.

If you have about 1/8 in-out play on the shaft, I would say you could be missing the spacer behind the gear, this would also explain the oil leak, since the spacer is what the seal rides on.
You must be logged in to view this image or video.


Now with the spacer missing , it would allow the gear to also grind into the front of the case.

So I would look at the area behind the gear first.

Then I would remove the bolt and gear and check for the spacer.
 

TSi-Rocket

Proven Member
189
26
Jul 12, 2003
Bryan, Ohio
Everyone is always so quick to eliminate the balancing shafts. With good reason, the balancing shafts are just one more thing that can cause problems with the timing belt, one more thing to fail ect.

Ive held that opinion since 2003 and eliminated them on the dsm's ive worked on. I came across this and am considering keeping them in my stock car.

http://www.jackstransmissions.com/pages/keep-your-balance-shafts
 

CrackedDSM

10+ Year Contributor
2,177
821
Dec 17, 2009
Pensacola, Florida
Everyone is always so quick to eliminate the balancing shafts. With good reason, the balancing shafts are just one more thing that can cause problems with the timing belt, one more thing to fail ect.

Ive held that opinion since 2003 and eliminated them on the dsm's ive worked on. I came across this and am considering keeping them in my stock car.

http://www.jackstransmissions.com/pages/keep-your-balance-shafts



The problem is from a physics standpoint, that doesn't make a damn bit of sense. At all. If this was the case mitsu never would've deleted the balance shafts on the mirage or there would've been massive problems. The balance shafts are connected to the crank by essentially a rubber band. They do not cancel vibrations, they actually vibrate in return so the person in the car doesn't /feel/ them, this doesn't mean they are cancelled out. Basically it's all a bunch of bullshit. The only reason I would keep any kind of balance shaft is if I was turning over 9000rpm, and I'd go with something like a "race shaft" due to reported oil pump problems with a stubby shaft and 9000+rpm passes.
 

19Eclipse90

DSM Wiseman
5,278
1,145
Sep 29, 2003
OKC, Oklahoma
If you have about 1/8 in-out play on the shaft, I would say you could be missing the spacer behind the gear, this would also explain the oil leak, since the spacer is what the seal rides on. [picture]
Now with the spacer missing , it would allow the gear to also grind into the front of the case.

So I would look at the area behind the gear first.

Then I would remove the bolt and gear and check for the spacer.
I was thinking the same thing, Dale. It seemed to me that the OP was inferring everything was fine up until hearing the noise and spotting the oil leak. If he has just done a balance shaft belt replacement or recently replaced that seal, that's probably the cause. If not, and assuming there was a time it was okay, there isn't much else to choose from aside from bearings unless it isn't from the balance shaft at all. The excessive movement seems to kill that idea.
 

Glover45

Probationary Member
14
0
Feb 15, 2015
Jones, Oklahoma
Hey guys I appreciate all the feedback sorry for being late to get back to this but that was where my leak was coming from. So I got a new seal and put it back together and now my leak is stopped but I removed the belt that drives that balance shaft and cranked it just to see if that was where my sound was coming from and it wasn't! I believe it to be that oil pump balance shaft making my noise and I'm about to lose my mind. This is a new motor with 130 miles on it. I don't know why it's doing this. But I'm running out of time, money, and patience. I don't really have the equipment to pull the motor and remove those balance shafts and I sure don't want to do it with the motor still in. So I'm not sure what to do but if you guys know of anyone in the Oklahoma City area that wants a 1g gsx with a great body and interior and brand new tires and a $600 tune on the ECU, by all means let them know about this one.
 

19Eclipse90

DSM Wiseman
5,278
1,145
Sep 29, 2003
OKC, Oklahoma
Did you build the motor or did you have it built by someone?

Have you dropped the pan to at least have a look?
 

Glover45

Probationary Member
14
0
Feb 15, 2015
Jones, Oklahoma
Did you build the motor or did you have it built by someone?

Have you dropped the pan to at least have a look?
No, I got it in pieces with a rebuilt motor and tranny but it was out of the car so I had to install it and hook everything else up. No I haven't pulled the pan yet I probably will though.
 

19Eclipse90

DSM Wiseman
5,278
1,145
Sep 29, 2003
OKC, Oklahoma
So does the person/outfit where you got the rebuilt motor from not warranty their work? I'm assuming the worst here but only 130 miles on an engine is pretty sorry. Wouldn't they at least want to look at it?
 

RipperXX

Proven Member
5,793
163
Feb 23, 2003
Royston, Georgia
Hey guys I appreciate all the feedback sorry for being late to get back to this but that was where my leak was coming from. So I got a new seal and put it back together and now my leak is stopped but I removed the belt that drives that balance shaft and cranked it just to see if that was where my sound was coming from and it wasn't! I believe it to be that oil pump balance shaft making my noise and I'm about to lose my mind. This is a new motor with 130 miles on it. I don't know why it's doing this. But I'm running out of time, money, and patience. I don't really have the equipment to pull the motor and remove those balance shafts and I sure don't want to do it with the motor still in. So I'm not sure what to do but if you guys know of anyone in the Oklahoma City area that wants a 1g gsx with a great body and interior and brand new tires and a $600 tune on the ECU, by all means let them know about this one.


If you think it can be limped about 100 miles, and you don't want to much for it, PM me a price.
 
Last edited:

Glover45

Probationary Member
14
0
Feb 15, 2015
Jones, Oklahoma
So does the person/outfit where you got the rebuilt motor from not warranty their work? I'm assuming the worst here but only 130 miles on an engine is pretty sorry. Wouldn't they at least want to look at it?
Well it has been about 6-7 years since that rebuild was done and when it was rebuilt it was owned by the guy I got it from who I have no way to contact so I don't know who rebuilt it and I doubt they'd warranty it being that it's been that long ago.
 

19Eclipse90

DSM Wiseman
5,278
1,145
Sep 29, 2003
OKC, Oklahoma
Ah, gotcha.

In any case, I'd still pull the pan to see what you can see. You did say there wasn't metal shavings when you drained the oil last time so, optimistically, it shouldn't be a complete loss.
 
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