Balance shaft housing.
10-13-2013, 04:07 AM
#1
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Balance shaft housing.
When rebuilding my engine, when installing the balance shaft bearings we cracked the lower housing on the engine.
This is how we found out that the bearings from the early block are larger from the late block and also another thing makes me wonder whats up with my engine with the mix of early and late bits.
We welded it up and it had an ever slight leak in it. lately it has been leaking like a tap. So we've gotten to it and trying to weld it up on the car. We failed, it's to dirty to weld properly.
We've got 2 options. Remove it and try weld it off the car (this involves cleaning it 100% securing it so it doesn't move ect) OR
buy a new housing.
Now IICR they're not interchangeable? is this true? or is it that no one is aware of the different bearing sizes? and they are interchangeable?
Thanks!
This is how we found out that the bearings from the early block are larger from the late block and also another thing makes me wonder whats up with my engine with the mix of early and late bits.
We welded it up and it had an ever slight leak in it. lately it has been leaking like a tap. So we've gotten to it and trying to weld it up on the car. We failed, it's to dirty to weld properly.
We've got 2 options. Remove it and try weld it off the car (this involves cleaning it 100% securing it so it doesn't move ect) OR
buy a new housing.
Now IICR they're not interchangeable? is this true? or is it that no one is aware of the different bearing sizes? and they are interchangeable?
Thanks!
10-13-2013, 04:54 AM
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Balance shaft housings are matched with the block since the bearings are alignhoned. So if you want to install another housing, you need to machine and alignhone the bearings again. Easier to find another block I guess.
10-13-2013, 05:52 AM
#3
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Why would you need to machine and align hone the bearings again when all replacement bearings are the same (except the 2 year differences) ?
10-13-2013, 09:12 AM
#4
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Paully
As above, the housings are specific to each block. The bearing as far as I know are the same. The late (87 on) have the bridge machined into the housing. The earlier ones have an independent bearing bridge.
As you cracked the housing I'm guessing you have an 87 style housing. If the housings aren't matched to the block, then the resultant bore for the balance shafts won't be right.
Care to elaborate a bit on exactly what cracked and whether you have the integrated caps on the housing. Did you make sure that you didn't mix up the upper and lower covers?
Funny you posted this, I just replaced my balance shaft bearings and seals today.
As above, the housings are specific to each block. The bearing as far as I know are the same. The late (87 on) have the bridge machined into the housing. The earlier ones have an independent bearing bridge.
As you cracked the housing I'm guessing you have an 87 style housing. If the housings aren't matched to the block, then the resultant bore for the balance shafts won't be right.
Care to elaborate a bit on exactly what cracked and whether you have the integrated caps on the housing. Did you make sure that you didn't mix up the upper and lower covers?
Funny you posted this, I just replaced my balance shaft bearings and seals today.
10-13-2013, 10:54 AM
#6
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The way it cracked was when we replaced the bearings they didn't sit right (ordered '86 rebuild kit as my car is an 86) we thought the bearings will push into place while putting the housing on. we started torquing and we heard a crack and realised the housing cracked. We ended up machining the bearings to fit. The 86 bearings are fatter then the 87 ones.
theres no way of mixing the 2 housings up as the top housing has an oil feed thread for the turbo and the bottom one is closed.
Integrated caps? the end caps with the o-rings?
Looks like i'll remove it tomorrow, clean it and put a nice solid weld on it. Because it's not a stress crack it shouldn't open up again.
theres no way of mixing the 2 housings up as the top housing has an oil feed thread for the turbo and the bottom one is closed.
Integrated caps? the end caps with the o-rings?
Looks like i'll remove it tomorrow, clean it and put a nice solid weld on it. Because it's not a stress crack it shouldn't open up again.
10-13-2013, 11:23 AM
#7
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Although not advisable, I have interchanged the covers before successfully. I did it with the engine out and a lot of measuring. I think this would be pretty difficult with the engine in. As I am sure you know, welding has its own risks due to warping. Any pics of the crack location?
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10-13-2013, 12:31 PM
#8
Drifting
When rebuilding my engine, when installing the balance shaft bearings we cracked the lower housing on the engine.
This is how we found out that the bearings from the early block are larger from the late block and also another thing makes me wonder whats up with my engine with the mix of early and late bits.
We welded it up and it had an ever slight leak in it. lately it has been leaking like a tap. So we've gotten to it and trying to weld it up on the car. We failed, it's to dirty to weld properly.
We've got 2 options. Remove it and try weld it off the car (this involves cleaning it 100% securing it so it doesn't move ect) OR
buy a new housing.
Now IICR they're not interchangeable? is this true? or is it that no one is aware of the different bearing sizes? and they are interchangeable?
Thanks!
This is how we found out that the bearings from the early block are larger from the late block and also another thing makes me wonder whats up with my engine with the mix of early and late bits.
We welded it up and it had an ever slight leak in it. lately it has been leaking like a tap. So we've gotten to it and trying to weld it up on the car. We failed, it's to dirty to weld properly.
We've got 2 options. Remove it and try weld it off the car (this involves cleaning it 100% securing it so it doesn't move ect) OR
buy a new housing.
Now IICR they're not interchangeable? is this true? or is it that no one is aware of the different bearing sizes? and they are interchangeable?
Thanks!
I had to use the passenger side (right hand side) cover
to chop it up to make a surface for the alternator mount bracket.
However you are welcome to my drivers side if you want it --
from an 86 951.
lmk,
just cover shipping.
Mike
10-13-2013, 06:22 PM
#9
Three Wheelin'
Paully as you are talking about housings again, it sounds like you don't have the typical '86 style which has separate bearing caps. If you install early bearings in a late housing you will have the problem you are reporting. Suggest you look at the FWSM Volume 1 which shows the differences.
10-13-2013, 08:40 PM
#10
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Although not advisable, I have interchanged the covers before successfully. I did it with the engine out and a lot of measuring. I think this would be pretty difficult with the engine in. As I am sure you know, welding has its own risks due to warping. Any pics of the crack location?
Yeah at the moment, i've removed the housing and now we're looking at it thinking how we're going to go about it.
Its cracked right through to the bearing support. probably machine some of the crack out and fill it with weld.
we'll be bolting it down before we weld it to avoid warping.
I just removed by balance shafts for my street/track car
I had to use the passenger side (right hand side) cover
to chop it up to make a surface for the alternator mount bracket.
However you are welcome to my drivers side if you want it --
from an 86 951.
lmk,
just cover shipping.
Mike
I had to use the passenger side (right hand side) cover
to chop it up to make a surface for the alternator mount bracket.
However you are welcome to my drivers side if you want it --
from an 86 951.
lmk,
just cover shipping.
Mike
Paully as you are talking about housings again, it sounds like you don't have the typical '86 style which has separate bearing caps. If you install early bearings in a late housing you will have the problem you are reporting. Suggest you look at the FWSM Volume 1 which shows the differences.
10-13-2013, 10:26 PM
#11
Drifting
M