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Discussion Starter #141
Thanks fellers.

I ripped the motor for this down today - for a few reasons.

1 - About 3 days after building this engine I had to take Mrs. Phreak to a fairly important doctors appointment on a stinking hot day. Aside from being new and tight i think the thermostat jammed closed and the motor overheated. Though this motor has now done 5,125 km in my standard with no apparent problems I feel better now that I have seen the bearings etc.

2 -I wanted to see the David Silvers camchain guide as there has been questions over the Silvers parts.

3 - This motor had a few minor noises from the top end even though camshaft and upper rockers and pins are new. Suspicion falls on the piston pins and exhaust valve guides, both of which will be replaced now and the heads then have their seats recut. The valves were only ground last time. Before dismantling the heads I'll put them on my head tester to make sure they've been holding pressure. These noises weren't actually there when the motor was first assembled. Overheat?

Everything was found to be good so after cleaning everything I'll just reassemble with the same parts - except for the piston pins and head rebuilds.

Camchain has plenty of adjustment left.

ozdmotorcrankpull 004.JPG

Outside of chain marked so it goes back in the same orientation.

ozdmotorcrankpull 011.JPG

The tensioner and guide. The guide is Silvers, the tensioner Honda. Both are still good.

ozdmotorcrankpull 007.JPG

Gearbox removed. This will just be put back as is.

ozdmotorcrankpull 012.JPG

I added pieces to my crank puller today so it could be used here. just needs a final cleanup and paint now. It works well.

ozdmotorcrankpull 019.JPG ozdmotorcrankpull 018.JPG ozdmotorcrankpull 013.JPG
 

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Discussion Starter #142
Crank and bearings all good.

ozdmotorcrankpull 017.JPG ozdmotorcrankpull 016.JPG ozdmotorcrankpull 014.JPG

I've brought the piston/rod assemblies inside to clean up tonight and to comparatively mic the old and new piston pins and fit the new ones.

I have a bit of cleanup to do but should start stuffing this back together tomorrow.

Once reassembled {the heads will be a holdup} I'll paint and detail it and stuff it into the Ozdeluxe. :)
 

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So is it fair to say that that is typically the state of the camchain adjustment after approximately 5,000 km? Cuz that would be good to know. And how does that current position compare to when the chain was first installed?
 

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Discussion Starter #146
Going back through the thread I found this from initial assembly.

oxdtensioner1.JPG

Be aware that as much as 1/3 of the adjustment range is generally used up on bed down, then movement through the adjustment range slows.

This is why it is important to do regular adjustments - especially on a new chain.

The motor I've just put in the standard to be tested has already had 2 adjustments at 60 kms {along with valves and head retorques, the next due when i refuel in another 60 - 70 kms.}
 

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Discussion Starter #147
Crank, rods and pistons reinstalled with new rings and piston pins and rehoned bores.

I decided to replace the rings because of the overheat as this can cause rings to lose tension.

Transmission and clutch refitted.

That's all I had time for today, but it's a start.
 

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How did the piston pins compare to the new one? Have you found anything that might be the reason for the extra engine noise after the overheat?
 

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Discussion Starter #149
The old pins still measured in tolerance but a couple thou below a new one - or their own unworn areas.

Wear is limited to where the pin rides in the rod.

The pins had a corrugated surface though, not reflected in the rod end.

I think the culprit is more the exhaust guides which I will replace.
 

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The old pins still measured in tolerance but a couple thou below a new one.
Phreak,

You being in OZ i'm surprised you said "couple of thou below"... Are you referring to thousands of an inch? If so, I applaud you. :D I realize metric units make way more sense than "imperial" units (LOL) but i was raised on imperial units and used them for 20 years in the manufacturing industry. When i was in grade school in the '70's they told us "One day america will switch to the metric system". Well it's almost 2020 and we still have gallons of milk, gasoline, ice cream, etc. wonder when we'll switch??? :D
 

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Discussion Starter #151
We went metric in 1974 and I'd already been taught imperial.

We did a stupid thing here when we changed over. Packaging etc. was not allowed to have imperial measurements to force us to learn the new system - thus removing the comparative yard stick meaning many people took longer to pick up the new system.

I was still at school though so was taught metric.

As this stuff was basically maths I was never good at it anyway and my thinking generally defaults to imperial for some things.

I will admit that in many measurements the metric system actually makes more sense. Freezing point being zero degrees is one of them.

Speaking of which, low to mid 40s for the next few days so I'll be starting on the heads - inside - near the aircon. :)
 

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I agree, metric makes way more sense but the whole old dog new tricks thing... All our measuring tools were imperial so the first thing we did if we got a metric blueprint was get out the calculator and pencil and divide everything by 25.4 and write it down on the print next to the metric number. Stupid way to do things but that's what we had to work with. The new tools that are digital can be changed by the flick of a switch, we had the old analog type so no go.
 

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Canada changed around the same time as Australia. We did it because our biggest trading partner (the US) had been officially metric for some time and it looked like they were going to start enforcing it and if we didn't do it too we would be left behind. We had been taught both systems in school so I was already familiar with metric when I started using wrenches as a teen (I quickly discovered that I didn't like working out fractions in my head so it was much easier to use metric wrenches) so I was pretty familiar with metric by then but I still thought primarily in imperial. Then I got my first motorcycle and started driving in Km and buying fuel in litres (but I still converted to imperial for fuel economy). A couple of years later the speaker company I worked for got a CNC saw that only spoke metric and the decision was made to start using metric in the wood shop; Since I was the engineering department I had to start doing all of the drawings for new models in metric and converting the existing models' drawings as they came up in production and by the time they were all done I was pretty good at converting fractions of inches to mm in my head.
I understand that there are economic reasons (the cost of replacing road signs &c) for the US to stick with their messed up version of the imperial system but it always bugs me when someone who has used metric currency all their life says they can't figure out metric weights & measures.
BTW: 50 years into the metric system the prices of things like meat and produce are still expressed with the $/LB in large bold characters and $/KG in smaller, non bold characters most of the time.
 

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Discussion Starter #154
I still convert litres to gallons {4.5 for ours} and work in MPG. Litres per 100 km still means nothing to me.

I used to have the fractional measures committed to memory but now only remember the basics - not the ones running to 64ths etc as it's so long since I've worked on imperial vehicles and really appreciate the simplicity of the metric nuts and bolts.

I still keep a full imperial drill set alongside my metric set. Handy for between size holes - especially when looking for that oddball number for drilling to tap for threads.

D-fresh. You should see my columns of addition on paper to do multiplication as my maths is appalling. I would multiply by 10 twice and then add half of one of these numbers then work out the .4 by addition. What maths I do know I taught myself from a book after leaving school. I wasn't a good student and maths my worst subject. I hated it.
 

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When you work with full size gallons Km/L X 2.85 = MPG

For some reason metric drill bits are still more expensive than inch sizes here if you can find them at all. I bought a basic set in eBay but I mostly use them for boring the hole to size after pre-drilling with the closest inch size below (determined by measuring with the digital vernier so I don't have to convert).
 

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Some things in metric are nice and simple and who ever the idoit that came up with litres per 100km is on my smack upside the head list. The other one that makes no sense to me is Newton metres , like what is a newton anyway. Myself I try use the system stuff comes in and not convert it back and forth.
 
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Pounds are mass. Newtons are force. Which makes more sense to measure torque, distance/mass or force/distance?

As for L/100 Km vs MPG (or KM/L), it all depends on whether you want to know how much fuel you will need to get where you are going or how far a specified amount of fuel will take you.
FWIW, Kay's "new" car displays the fuel economy in L/100 and the maths is easier so I've decided it is about time I started thinking in that term.

You want to hear something metric that is genuinely confusing? The size of textile fibres was traditionally measured in Cotton Count and some fibres are still measured that way but the majority of man made fibres are measured in denier, which is the number of grams that 9,000 M of the fibre weighs (even the Yanks use denier). But somewhere along the way someone decided (correctly) that a unit based on 9,000 metres of something didn't fit properly in the metric system so they invented the "tex" which is defined as the mass in grams of 1000 M of a fibre and the decitex (dtex), 1/10 of a tex or the number of grams in 10,000 M of the fibre.
For most purposes dtex is the normally used unit and it really does make more sense than denier BUT since denier was used earlier and most people in the industry were familiar with it most yarns are still made in denier sizes.
"No problem" you say "They are both metric so just convert". Well, it is easy to convert dtex to denier (dtex x 0.9 = denier) but when you convert the other way you have to multiply denier by 1.11111111 to get the actual dtex value. This means that a 1000 denier thread (a very common size) is 1,111.1111 dtex.

"OK, so that is close enough to 1,100 that you can round it down", which is what the industry generally does but it doesn't work in all instances. I spent the last half of my working life in the textile (rope making) industry and when I had to figure out how many so-called "1100 dtex" threads I needed to twist together to make the size of yarn needed for a rope I was making I always had to take that into account.

Anyway, I think that's about enough of a thread hijack for now (unless you guys still want to talk about it)....
 

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Discussion Starter #160
Not much accomplished this weekend, my activities dispersed doing a number of different things.

But, I have refitted the gearchange linkages, camchain, tensioner components and rotor.

The motor is now just waiting for heads and covers. The covers are getting a bit of cosmetic work.
 
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