V12 con rod advice please?
#1
V12 con rod advice please?
Hi,
I am collecting parts to start to rebuild my 140,000 mile 5.3 HE. I have been offered a set of NOS con rod assemblies part number JLM12044 which I think are a later alternative part number to the ones fitted in my engine. Do I risk using the existing ones in my engine or swap to the later part number? I cannot find any info on the JLM12044 con rod to decide if it is a better design. What are people’s thoughts?
Andy
I am collecting parts to start to rebuild my 140,000 mile 5.3 HE. I have been offered a set of NOS con rod assemblies part number JLM12044 which I think are a later alternative part number to the ones fitted in my engine. Do I risk using the existing ones in my engine or swap to the later part number? I cannot find any info on the JLM12044 con rod to decide if it is a better design. What are people’s thoughts?
Andy
#2
Hi,
I am collecting parts to start to rebuild my 140,000 mile 5.3 HE. I have been offered a set of NOS con rod assemblies part number JLM12044 which I think are a later alternative part number to the ones fitted in my engine. Do I risk using the existing ones in my engine or swap to the later part number? I cannot find any info on the JLM12044 con rod to decide if it is a better design. What are people’s thoughts?
Andy
I am collecting parts to start to rebuild my 140,000 mile 5.3 HE. I have been offered a set of NOS con rod assemblies part number JLM12044 which I think are a later alternative part number to the ones fitted in my engine. Do I risk using the existing ones in my engine or swap to the later part number? I cannot find any info on the JLM12044 con rod to decide if it is a better design. What are people’s thoughts?
Andy
Greg
#4
Con rods
The engine has had a hard life with most of the oil is on tbe outside.....and was used to hammer arround tbe yard a few times so am not to if it has been over reved perhaps? With thw xhance of swapping tbem out cheaply sounds good but I couldnt find out if the new con rods would be better or worse??
#5
Sorry I should have read the post before sending!
The engine has had a hard life with most of the oil being on tbe outside.....and was used to hammer around the yard a few times so am not to if it has been over revved perhaps? With the chance of swapping them out cheaply sounds good but I couldnt find out if the new con rods would be better or worse??
The engine has had a hard life with most of the oil being on tbe outside.....and was used to hammer around the yard a few times so am not to if it has been over revved perhaps? With the chance of swapping them out cheaply sounds good but I couldnt find out if the new con rods would be better or worse??
#6
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#8
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Greg in France (05-09-2018)
#9
OEM conrod bolts are fantastically expensive, you might find it quite a bit cheaper to buy these bargain NOS rods.
#10
I have just been through this.
From experience. I would replace the bigend bearings only, if the rod stud threads are ok I would not replace them. If you do replace them then you will need to have the big ends honed.
Mark each rod, pin and piston so they go back with their mate, or you will need to replace everything.
One thing I found was I had one rod out of spec, it was 0.020" short, it was still used but as I replaced pistons with Chevy its mating piston was modified to ensure compression height was correct.
From experience. I would replace the bigend bearings only, if the rod stud threads are ok I would not replace them. If you do replace them then you will need to have the big ends honed.
Mark each rod, pin and piston so they go back with their mate, or you will need to replace everything.
One thing I found was I had one rod out of spec, it was 0.020" short, it was still used but as I replaced pistons with Chevy its mating piston was modified to ensure compression height was correct.
#12
Join Date: Jul 2012
Location: Walnut Creek, California
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Yup.
Pretty much standard auto machinist practice. Put on a stands to assure alignment of small to big openings, fix and any bend or twist. If minimal, o'wise do not use. Grind the flats on the big end. Hone to assure they are round, Not egg or oval.
If doubt, magnaflux for unwanted cracks. Use new bolts.
If one or more let's go, it is pure mayhem.
Oh, balance them. a large and small end technique.
Carl.
Pretty much standard auto machinist practice. Put on a stands to assure alignment of small to big openings, fix and any bend or twist. If minimal, o'wise do not use. Grind the flats on the big end. Hone to assure they are round, Not egg or oval.
If doubt, magnaflux for unwanted cracks. Use new bolts.
If one or more let's go, it is pure mayhem.
Oh, balance them. a large and small end technique.
Carl.
#14
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ronbros (05-10-2018)
#17
Koenig swb body kit XJ12
Hi,
I am collecting parts to start to rebuild my 140,000 mile 5.3 HE. I have been offered a set of NOS con rod assemblies part number JLM12044 which I think are a later alternative part number to the ones fitted in my engine. Do I risk using the existing ones in my engine or swap to the later part number? I cannot find any info on the JLM12044 con rod to decide if it is a better design. What are people’s thoughts?
Andy
I am collecting parts to start to rebuild my 140,000 mile 5.3 HE. I have been offered a set of NOS con rod assemblies part number JLM12044 which I think are a later alternative part number to the ones fitted in my engine. Do I risk using the existing ones in my engine or swap to the later part number? I cannot find any info on the JLM12044 con rod to decide if it is a better design. What are people’s thoughts?
Andy
#18
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