Piston size
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admin_maintenance
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- Location: Mackay
Piston size
This is the top of my piston. I am reading this right that it is 10 thou???
Re: Piston size
.001 would be one thou ????
I started with nothing and still have most of it left.
Foundation member #61 of FB/EK Holden club of W.A.
Foundation member #61 of FB/EK Holden club of W.A.
Re: Piston size
Hard to tell,
You would need to measure it with a set of vernier calipers.
Greg
You would need to measure it with a set of vernier calipers.
Greg
Last edited by EK283 on Tue Jul 06, 2021 8:43 pm, edited 1 time in total.
So many cars so little time!
Re: Piston size
Agree - vernier it.
The originals were stocked as standard, 1-thou oversized, 2-thou, 3-thou, 20-thou, 30-thou and 40-thou.
Cheers,
Harv
The originals were stocked as standard, 1-thou oversized, 2-thou, 3-thou, 20-thou, 30-thou and 40-thou.
Cheers,
Harv
327 Chev EK wagon, original EK ute for Number 1 Daughter, an FB sedan meth monster project and a BB/MD grey motored FED.
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admin_maintenance
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Re: Piston size
Ok thanks. This is the original engine out of my FJ. Just wondering if I should get it rebored or re-ring it.
Ive had the car 35 years and I have never rebored the motor so I would not be surprised if it is only 1thou
Thoughts
Jason
Ive had the car 35 years and I have never rebored the motor so I would not be surprised if it is only 1thou
Thoughts
Jason
Re: Piston size
Jason,
The .001 here is the specified clearance between piston skirt and bore.
The oversize (if any) will be on the next couple of lines of text. I can just make out STD below. These are Repco (ACL) pistons, so the motor's already been rebored. My guess is that the pistons will be 3.0625", with an outside chance of 3.125". Measure across the bottom of the piston skirt.
Rob
The .001 here is the specified clearance between piston skirt and bore.
The oversize (if any) will be on the next couple of lines of text. I can just make out STD below. These are Repco (ACL) pistons, so the motor's already been rebored. My guess is that the pistons will be 3.0625", with an outside chance of 3.125". Measure across the bottom of the piston skirt.
Rob
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admin_maintenance
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Re: Piston size
I think it read 3 or 2 075 STD If that makes more sense
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admin_maintenance
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Re: Piston size
A quick measure with some calipers??
Re: Piston size
3" + two small divisions + about half a small division (vernier scale is affected by camera parallax), which is
3.000 + 0.050 + 0.0125 = 3.0625". This is standard bore size for a 138 grey.
The Repco part number for the pistons is RA2075.
How good are your gudgeon pins? Can you rock the big end back and forth (not side-to-side) at all? If there's any perceptible play, it's best to get new piston pins (Nornda aka JP in Adelaide), new small-end bushes, and have the bushes replaced and reamed to size.
Rob
3.000 + 0.050 + 0.0125 = 3.0625". This is standard bore size for a 138 grey.
The Repco part number for the pistons is RA2075.
How good are your gudgeon pins? Can you rock the big end back and forth (not side-to-side) at all? If there's any perceptible play, it's best to get new piston pins (Nornda aka JP in Adelaide), new small-end bushes, and have the bushes replaced and reamed to size.
Rob