BBC thrust bearing
#1
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i am in the process of rebuilding a Big block 454 that had been torn down due to excessive crank endfloat.
i am wondering how to go about rectifying this.
it will be fitted with 10 thou oversize mains, does this mean it will also have an extra 10thou taken up the thrust mesurement aswell?
can u buy bearings with thicker thrust sufaces?
any help would be much appreciated.
i am wondering how to go about rectifying this.
it will be fitted with 10 thou oversize mains, does this mean it will also have an extra 10thou taken up the thrust mesurement aswell?
can u buy bearings with thicker thrust sufaces?
any help would be much appreciated.
#2
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I don't usually view this section but I did this evening. The thrust face on the crank will most likely need repair. This can be done by welding it back to stock or by grinding it flat and smooth again if it is not too badly worn. Clevite makes a .010" under main set that has a .010" wider thrust bearing. Part number is MS 1745P-10
You need to find out why the thrust face, bearing failed or you will end up with another failure. If this is an automatic, make sure the converter has not ballooned out.
Steve
You need to find out why the thrust face, bearing failed or you will end up with another failure. If this is an automatic, make sure the converter has not ballooned out.
Steve
Originally Posted by dan05k
i am in the process of rebuilding a Big block 454 that had been torn down due to excessive crank endfloat.
i am wondering how to go about rectifying this.
it will be fitted with 10 thou oversize mains, does this mean it will also have an extra 10thou taken up the thrust mesurement aswell?
can u buy bearings with thicker thrust sufaces?
any help would be much appreciated.
i am wondering how to go about rectifying this.
it will be fitted with 10 thou oversize mains, does this mean it will also have an extra 10thou taken up the thrust mesurement aswell?
can u buy bearings with thicker thrust sufaces?
any help would be much appreciated.
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
#3
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ok, i was hoping that i wouldnt have to send the crank away to be repaired.
i might try using those bearings u mentioned, then check endfloat again.
if that dosent take up the amout mesured up to spec, then i will send the crank away.
as for why it has suffered this endfloat, i am not 100% shure.
it was used in a truck under extreme loads, over very long trips.
Being a 2bolt block, possibly it just wasnt up to the task,
and has actually worn the mains and thrust surfaces fasted than the big ends.
I have checked the main bearing tunnel alignment, and found nothing unusual.
I am going to give the crank the usual checks for run out, bend, ovalily of journals ect. this weekend.
thaks for your assistance.
i might try using those bearings u mentioned, then check endfloat again.
if that dosent take up the amout mesured up to spec, then i will send the crank away.
as for why it has suffered this endfloat, i am not 100% shure.
it was used in a truck under extreme loads, over very long trips.
Being a 2bolt block, possibly it just wasnt up to the task,
and has actually worn the mains and thrust surfaces fasted than the big ends.
I have checked the main bearing tunnel alignment, and found nothing unusual.
I am going to give the crank the usual checks for run out, bend, ovalily of journals ect. this weekend.
thaks for your assistance.
#4
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iTrader: (1)
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The bearings I speced with the wider thrust are available only in .010" under on the journal diameter. The crank must be ground regardless.
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net