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1970-1995 Range Rover Classic
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Discussion Starter #1
1995 Classic with 3.9L engine with 185k miles

I've removed my pistons to install new rings and some of the bearing shells are worn and showing copper. Can I just order a new standard set and replace them (machining the crank at this point is not feasible for me)?
 

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1995 Classic with 3.9L engine with 185k miles

I've removed my pistons to install new rings and some of the bearing shells are worn and showing copper. Can I just order a new standard set and replace them (machining the crank at this point is not feasible for me)?
Based on my personal experience right now! I strongly suggest you do research and evaluate your action with regards the cylinder wall and new piston rings.

The ideal scenario is that you remove the block, strip it have it bored out, honed and fit oversized pistons and with new rings. I know I did not do that either as it would cost a fortune and you can question the value for older vehicles. So instead you work on the block while fitted in the car and you skip a few steps to keep the cost down. But you can end up with poor results that renders your motor (engine) worthless.

I am learning the hard way (see other thread currently ongoing). So I am wondering what new rings would do in a clean cylinder (no honing). Will the rings settle or will you have low compression, blow by and high oil consumption? One thing i learned that if you hone in situ you have to clean it all REAL GOOD!

The bearing question is easier: New shells are cheap and unless you plan to remove your crank have it ground and fit bigger shells etc, you might as well just change the shells and watch the oil pressure. You can do clearance measurements using platicgauge, but assuming you have no oil pressure issues before the clearance should be good.
 

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1970-1995 Range Rover Classic
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Discussion Starter #5
JS5D After inspecting the cylinder walls I think I should be ok. The cross hatch is still very prominent and compression was decent. I'm just doing new rings because i've got everything apart. I do have a cylinder hone and wonder if I should just do a very very light honing before I put the pistons back? But yeah, with an engine this old I don't want to do a full rebuild - I'm hoping to get another 50-60k miles out of it, then put something in it with more mojo. Time will tell...
 

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I would agree on the point that you should definitely give the cylinders a light hone to break the glaze. A tri-stone hone is very cheap and easy to get a hold of at any store that sells small engine tools. However, if you weren't having any serious issues with it and just changing the rings because it's old and tired, then getting it bored out and buying new pistons is overkill.

EDIT: You have a hone so definitely give it a run through the cylinders to break any glaze. Just make sure to lay a rag or towel over the crank to try and keep any grit out and make sure the cylinders are squeaky clean before reinstalling pistons.

Good Luck
 

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Discussion Starter #7
Great tip about the covering the crank!
 
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