Oil pump drive shaft bearings and hot tanking

gaboonviper85

gaboonviper85

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Jan 13, 2008
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Can someone go into more detail about what exactly will happen? I picked up a gte shortblock and it's almost ready to head to the machinist but obviously it needs cleaning....I need details on how to install new bearings and what exactly I need to do....I think I read somewhere that the shaft may need to be machine'd or some shit....I'm under the impression that most reuse those bearings?!

Just need to know all the facts on the oil pump assembly in general....not worried about freeze plugs cause those are cake.
 
Poodles

Poodles

I play with fire
Jul 22, 2006
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Hot tanking is done with acid that will eat the bearings, that's why they need to be replaced and then sized (royal PITA).

Can be cleaned with a sonic cleaner and it won't eat the bearings IIRC...
 
gaboonviper85

gaboonviper85

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Yeah I know that....but i've worked plenty with ultasonic cleaners and was never impressed....I want this block clean...very clean....thinking hot tank then ultrasonic....

I want to know what's involved with sizeing....need the down low on that and installation.
 
Poodles

Poodles

I play with fire
Jul 22, 2006
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Have to either size the shaft or the bearings. Did I mention the bearings are a bitch to install? Have to get the oil holes aligned, get em square in the bore, ect... Overall it's one of those things that if they fuck up the engine will suffer a bad failure...
 
gaboonviper85

gaboonviper85

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Poodles;1187831 said:
Have to either size the shaft or the bearings. Did I mention the bearings are a bitch to install? Have to get the oil holes aligned, get em square in the bore, ect... Overall it's one of those things that if they fuck up the engine will suffer a bad failure...
Click to expand...

By they you must mean me LOL...only thing that machinist is gonna do is machine the block as I don't have the machines to do it myself....sizeing the shaft should be cake work on the lathe...yeah I can see getting the bearing in isn't gonna be fun but if it's not impossible then I'm sure I'll be fine. Just didn't know exactly what's involved.

Thanks.
 
Poodles

Poodles

I play with fire
Jul 22, 2006
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If you can machine up the SST to install them it's not nearly as hard to get them in, but you still have to line them up with the oil holes.

TSRM has the instructions...
 
I

IJ.

Grumpy Old Man
Mar 30, 2005
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In the "old days" with SBC's I just left a Cam in the block and the bearings survived the hot tanking just fine.

Never done it with a 7M though so can't say one way or the other.

It would be worth a try Goon then if it fails just replace em and we know for sure ;)
(it's only 2 bearings and they're cheap)
 
gaboonviper85

gaboonviper85

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Say I did leave them in with the shaft installed....they survive....how would it effect them long term...will it soften the material? I'd be scared that the bearings blow after 500 miles or something....or is it just the heat that makes them fall out?
 
I

IJ.

Grumpy Old Man
Mar 30, 2005
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Goon: What happens if you don't put a shaft in is it eats the babbit material off the bearing, with the shaft in place (at least with small block chevs) it would etch the edges but not touch the babbit surface and it would be fine to run.
 
nosman4

nosman4

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Wouldn't it be a better idea to remove some material from the bearings rather than size the shaft to fit the bearings? The bearings from my knowledge are one solid material, unlike engine bearings, so it shouldn't affect how the bearing works as long as the surface of the bearing is round and smooth when you're done.
 
gaboonviper85

gaboonviper85

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Ok I'll leave the shaft in...

Machinist quoted me $134 for hot tank and magnaflux....

I'm sure I can replace the bearings if needed I just wanted to get a heads up before I dive in.

And no it would be much much easier to size the shaft than the bearings.
 
JDMMA70

JDMMA70

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Dec 4, 2006
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Glad this thread popped up im also having my block hot tanked and im having my machinist replace the oil shaft bearings.
 
grimreaper

grimreaper

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Jul 2, 2008
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how does keeping the cam in keep the bearings intact if there is already clearance for oil?
the chemical bath doesnt penetrate like oil perhaps?
 
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