Reusing piston rings.

[Call the midlife!]

Bear with me, it's a long one...
Anyone familiar with my engine building trials and tribulations will understand this more but I'm open to any answers.
I recently picked up a "spare" engine for peanuts, allegedly a 94k non oil burner, I've so far checked the valve gaps, reasonable and taken the head off.
Bores look nice, still cross hatched and minimal glazing but I've yet to pull the pistons out and check the crank/journals etc.
My intention is to give it a once over, a good clean and probably a new sump and then bolt my current head on it and stick it in the car because A: mine uses a LOT of oil and B it needs the tune sorting and the oil burn/rich running keeps killing wideband sensors.
Then assuming all that gets sorted and my block measures out correctly I'll rebuild it and swap back as all the ancillaries, pumps and chain etc are less than 4k miles old.
As long as I put everything back where it came from can I get away with using the original rings to negate the need for running in? Bearing in mind the way it's running and the assumption it's that that screwed the running in process on the rebuild and subsequent oil usage.
I think I know what the answers will be but never hurts to ask 🤓.

[Carolyn]

Just 'cos you can see some cross-hatch, doesn't mean  the bores aren't glazed.  With that mileage, I'd give it a a good honing until all the shine is gone, and put in new rings.  Then run them in properly.

Silly to take the risk on an engine with such mileage.  If you put it back in and it went through oil - you'd be very very unhappy.

You KNEW I'd say that!! 

[Call the midlife!]

I know, I know exactly where you're coming from trust me. The more I look at the position the less I know which way to go, it's the same financial outlay whether I rebuild the spare and stick with it or rebuild mine again.
But if I rebuild the spare AND mine I'm into 2 lots of sets of gaskets/seals etc.
I could take the risk and transfer all the new bits over to the spare block with theoretically 30k less miles on it and keep my fingers crossed...

[Carolyn]

When you've got the pistons out of the spare, you'll see what condition the shells are in.  If they're clean - I'd go with your head on that block and bottom end. So it's one set of gaskets and bolts and one set of rings.

I'd trust that over the bores that are in the car right now - I've SEEN the oil consumption and it's biblical!  ( I really didn't have to tell you that, did I?).

[Call the midlife!]

😆😆😆 I've probably spent two gasket sets worth of in oil the last couple of years just topping it up.
I've got ARP head bolts in mine currently so I'll probably use those, unless they come cheap enough with the head gasket kit.

[jonbill]

a set of rings costs peanuts,I'd always flexi-hone and give it a new set of rings if you've got it in bits.

[Call the midlife!]

a set of rings costs peanuts,I'd always flexi-hone and give it a new set of rings if you've got it in bits.

It's not the money saving aspect of it, that's not an issue, I was trying to avoid another failed running in period while getting it running as it should.

The more I think about it the more reasons I can find for transferring the new bits over to the replacement engine and starting from scratch again almost, even potentially swapping the cams into the replacement head, bearing in mind the vvti filter housing is helicoiled on the current head.
I'll see what pistons are in the spare block and take it from there as I replaced mine with the upgraded ones with the extra holes.

[Carolyn]

a set of rings costs peanuts,I'd always flexi-hone and give it a new set of rings if you've got it in bits.

It's not the money saving aspect of it, that's not an issue, I was trying to avoid another failed running in period while getting it running as it should.

The more I think about it the more reasons I can find for transferring the new bits over to the replacement engine and starting from scratch again almost, even potentially swapping the cams into the replacement head, bearing in mind the vvti filter housing is helicoiled on the current head.
I'll see what pistons are in the spare block and take it from there as I replaced mine with the upgraded ones with the extra holes.

In that case, I think you're best to swap the pistons on to the rods from the replacement engine. (Assuming the shells look good).  That way the rods and shells are matched to the crank I wouldn't worry about the
helicoil...

OR:  If you want to send us the pistons (still on the rods) we'll modify them for you.

We so want you to end up with a good engine.

[Call the midlife!]

Aye, if they're not already the updated pistons in the spare lump then it'll be the ones I have going onto the spare rods, as you say. 
The helicoiled plug has been fine since I repaired it, as far as I know so I hear what you're saying and as the valves were all lapped into the head you can guarantee the gaps will be away with the fairies if I swap it all across.
I'll see if I can find the engine number on Saturday when I get to it again but I'll probably get a full gasket/seal kit again and swap the oil pump etc across as well as they're practically brand new.
And a new sump, the one on the spare engine is rusty as and a bit out of shape from dragging it around a bit and the one on the car only has around half the threads in the plug hole...

[Carolyn]

I've used a few of these with good results:

https://www.ebay.co.uk/itm/HEAD-GASKET-SET-BOLTS-FITS-AVENSIS-CELICA-COROLLA-RAV4-MR2-1-4-1-6-1-8-VVTi/310790776292?hash=item485c92e5e4:g:CewAAOxyXDhSfWHl

[Call the midlife!]

I've used a few of these with good results:

https://www.ebay.co.uk/itm/HEAD-GASKET-SET-BOLTS-FITS-AVENSIS-CELICA-COROLLA-RAV4-MR2-1-4-1-6-1-8-VVTi/310790776292?hash=item485c92e5e4:g:CewAAOxyXDhSfWHl

I've still got that on my watching list from the last time I asked for recommendations 😃 but thanks again.

I'm sure the last time it worked out best value to get the full kit for around £125, all crank seals, oil pump and thermostat gaskets etc.

[jonbill]

I wouldn't worry about running rings in.
if you keep it at 2k rpm or more for 30 mins on first start, the rings have been up and down 60,000 times already and you can drive it mormally.

[Call the midlife!]

I wouldn't worry about running rings in.
if you keep it at 2k rpm or more for 30 mins on first start, the rings have been up and down 60,000 times already and you can drive it mormally.

I'll certainly be doing it better than the last time regardless of what method I choose, it won't be fired up freshly rebuilt and limped to the exhaust manufacturer then thrashed on the dyno with mineral oil in still.

So many things went wrong/were done badly the first time around I class it as a minor miracle it even runs, let alone keeps up with the others when we're out 🤓

[Call the midlife!]

Hmmm... wonder what happened there then? No witness marks anywhere on the cams or valves, see if there's anything in the sump when I take it off.
There's some curved notches on one of the sensor flags on the end of the camshaft but they're even and uniform and look factory.

[Carolyn]

Somebody tried to undo the head bolt with that still all the way in.

[Call the midlife!]

Somebody tried to undo the head bolt with that still all the way in.

Well "somebody" is an idiot and ought to know better then, especially as they've now not got a spare one after all...😆

[Carolyn]

I've got a spare -but you should be ok using the one in your high performance head?

[Call the midlife!]

I've got a spare -but you should be ok using the one in your high performance head?

Sorry yeah, what I meant was now I've mullered that one through carelessness it's not going in the spares bin after all, just the bin...🤓

[1979scotte]

Ah the joys of amateur mechanics.

[Call the midlife!]

Ah the joys of amateur mechanics.

I prefer to call it "having a go with a can do attitude.."

Must've got away with it the first time.

[Call the midlife!]

Carried on stripping the spare engine this afternoon after getting soaked putting the winter wheels on the bus for next week.
It's now disassembled and had a quick clean, all but the pistons that are still wearing the rings.
Looks generally in good shape apart from the con rod bearings which will definitely be getting replaced, subject to a closer look at the crank tomorrow.
Ignore the marks on 2 and 3, I made those knocking the pistons out once I'd seen the condition of the number 1 bearings.

[Carolyn]

That's been oil starved - You'll need to look at the mains as well.

[Call the midlife!]

That's been oil starved - You'll need to look at the mains as well.

That's what I thought but the mains don't have a mark on them, at least not like 1 & 4, I'll have a better look tomorrow when I've cleaned them, I just bagged them up after removing them today.

There was no noise or movement from any of them when I manipulated them before stripping it.

[Carolyn]

That's been oil starved - You'll need to look at the mains as well.

That's what I thought but the mains don't have a mark on them, at least not like 1 & 4, I'll have a better look tomorrow when I've cleaned them, I just bagged them up after removing them today.

There was no noise or movement from any of them when I manipulated them before stripping it.

If they're clean, I'd put them back as they're factory matched to the engine.  I'm sure the crank will be fine -probably a bit of white metal pick-up on 1 & 4.  Fine wet and dry  will sort that.

[Call the midlife!]

That's been oil starved - You'll need to look at the mains as well.

That's what I thought but the mains don't have a mark on them, at least not like 1 & 4, I'll have a better look tomorrow when I've cleaned them, I just bagged them up after removing them today.

There was no noise or movement from any of them when I manipulated them before stripping it.

If they're clean, I'd put them back as they're factory matched to the engine.  I'm sure the crank will be fine -probably a bit of white metal pick-up on 1 & 4.  Fine wet and dry  will sort that.

I bagged and tagged them straight off the housing but looked ok as I bagged them up but I'll clean them tomorrow.

I'll get my shoelace out again and give the crank a looking at before it all eventually goes back together.
The block needs a good boiling up in my diy parts cleaner before it goes anywhere near my engine bay though. And a new sump, I'd be surprised if the current one wasn't leaking and 3 or 4 of the mounting screws were very crusty, had to tap the 10mm firmly on before risking turning it.
The pulleys are all crusty too and I cut the belt off as that was very tired.
Just need to get a dial gauge, matching micrometer and check the bores, then some honing balls and I'll throw it all back together ready for fitting the head off mine once it's been skimmed.