Don't ya hate it when.............after all this time, all is about to proceed with my engine re-build and there's one thing I've forgotten to get, new thrust bearings....bugger.

Ah well, I've put the crank in, torqued it down, spins beautiful, taken the bearings off again and no annoying scratches or marks anywhere....Gotta love that.

I've measured the end float with the old thrust bearings installed...the feeler gauge that will fit is .004" so the gap is actually bigger than this. Spec is .002" to .003". I've also set up a dial gauge indicator and it goes out to .002mm if I'm reading it right.

Never mind.....push on with getting the pistons assembled and ready.

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

Want me to buy anything in North Geelong Rod ?

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'98 Mpi Sportspack + 7 port alloy head

Thanks but no thanks Bob......already got a set on the way.

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

Geez you've had some holdups with this mate.......


.002mm?? That's less than one ten-thousandth of an inch Rod. You sure the clock's not imperial?

There's a piston ring compressor in the shed if you need it for the assembly mate.

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Cheers,
Rod.
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'63 Morris 850 (Old Secondhand CAR)

Hi Rod.....nah mate, I'm just an idiot. The gauge is in mm's so I reckon there's one or two too many zeros in my previous post

I've got a piston ring compressor thanks Rod. Also got the correct tool to put the rings on the pistons.....hope it's not too big

See ya when you get back from the west mate.



By the way.....the new set up with the router works a treat, but Jan had to get another password and spend some time on the phone to the dudes.....thanks again mate

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

Checking my box of Hastings Piston Rings......as per normal, they're packaged 'Top Groove' and so on. The ones for the top and second groove are flat rings ie no bevel or dot, but the ones for the 3rd groove have a step on them, again, easy to see top from bottom. But my question is......shouldn't the rings in the first three grooves be the same type???

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

The 3rd ring if fitted, (most modern 1275 ones don't) is mostly a scraper ring to help the oil ring keep the oilz down below, where it belongs. So it is often of different design.
Check your top rings again though, both my Hastings top and second ones have a tiny bevel inside, at bottom.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Thanks Kev. Knew i could rely on you for the correct answer

I'll have another look under some bright lights at the top two rings, but there doesn't appear to be dots or bevels present.

Time to get out the magnifying glass perhaps.

Cheers

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

More piston ring questions....

Here's a photo of the oil ring that I've just installed on the first of my new pistons. It's a four part set up....the spring ring followed by the scraper ring and then spacer rings top and bottom. I've only installed one of the spacer rings at the moment.

Shouldn't the spring ring meet???

Shouldn't the scraper ring meet???

The gap that you can see on the scraper is 17mm and the gap on the spring ring (that of course cant be seen) is similar.


The cir-clip doesn't look in the right position in this pic!

Ok...out in the garage having another go at this.....remove the spring ring and everything fits good, ends meet up etc. But, the spring ring is forcing things out of the slot..... Also, the spring ring is the same width as the slot, which is why the two spacer rings wouldn't go to the bottom of the slot.

I'm obviously doing something wrong.

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

BUMP

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

Rod, just for fun, take the flat bumpy inner expander ring out and wrap the spacer back around the piston. The ends should touch and it should be a bit loose when rattled about. If so it is correct, proceed to assemble.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

G'day Kevin, yep...did that and the two spacer rings and the scraper ring then fit beautiful. So you're saying to just leave that spring ring in the pack and not worry about it?

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

NO!!!
I'm saying when it's all compressed and in the bore, it will work fine, WITH the flat expander.
You do need a good ring compressor....

Been there, built a 1098 motor once without the expander, and it drank oil...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Hey Kev,
Rod here...just that Jan is logged in at the moment

So, it has to be how I had it originally......when it looked wrong!! With that bloody big gap!!!! It just looked so wrong, plus the fact that the groove in the piston doesn't seem to be wide enough. But, as you say, when it's compressed, it will be ok.

Wish I had a see through test bore

Thanks again Kev.

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Jan.

Hey Rod.
One week on and I'm back catching up on all the goss - only a week-n-a-bit til I come home for R&R again!

Reckon you'll be on the road by then mate?

Hope you checked over all those circlips after the previous pic - that one aint locked in the groove!

You probably know this already, but make sure you stagger the position of the ring grooves before you install the pistons in the bores too.


Speaking of tiny measurements....
I was monitoring the alignment of the largest compressor (about 250 tons worth) on this site with the laser gear yesterday whilst a crew was installing the inlet pipework. A bit of a shift resulted in one of the angular readings to be .001mm (.00004") out of spec. It took the powers-that-be some hours of deliberation to decide to proceed with the job. The coupling that will be installed can handle 2mm of mis-alignment!!!!!!!!


PS. Glad to hear the router setup worked OK - I was wondering about that....

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Cheers,
Rod.
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'63 Morris 850 (Old Secondhand CAR)