Leak Down Test (Don't Laugh!!)

Fast Eddie

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Advice to apply take to rods is good.

Advice to remember to remove it is even gooderer
 

click

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And the game now is, what cam do I have?

I used a digital vernier, had the edge resting on the case & used the depth gauge & dropped it down to the back of one of the cam lobes & zeroed the vernier. Then I rotated the engine so the cam lobe was now at it's highest point & measured again.

I got a reading of 0.32" for an exhaust lobe, I think it's the standard 061084 cam??

It's not the most accurate way of checking the cam but it's the only way I have of measuring the cam!
 
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click

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Advice to apply take to rods is good.

Advice to remember to remove it is even gooderer
More post-its all over the bike!! I tend to put post-its, strategically placed in my line of sight so I don't forget a step or a washer/nut etc!!

Not that anybody on this forum would leave tape on the conrods!!!

Pete Lovell told me a great story, he built a Norton race engine at short notice so things were hectic getting everything ready, when he was about to fit the barrels he couldn't remember tightening the conred bolts!! He was 99% sure he did BUT was not 100%. He made up a 'special' tool so he could get at the conrod bolts & check if they were tight, which they were!
 
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I`ve got some heavy weight barrels on the shelf that measure out at about 890cc and would be interested to know what pistons might fit if you`ve come across these before.

http://s628.photobucket.com/user/skip-rat/media/Norton/IMG_2283_zpsdqqg1zgx.jpg.html?sort=3&o=7

Regards, Al.
Interesting. So the bore would be around 80MM with no separate sleeves? I only know of one large iron barrel built, and it was whittled from billet. Jim
Yes, 80MM and no sleeves, I thought i`d added a couple more photos but apparently not, I`ll try again.

http://s628.photobucket.com/user/skip-rat/media/Norton/IMG_2285_zpszgyy57rm.jpg.html?sort=3&o=7
http://s628.photobucket.com/user/skip-rat/media/Norton/IMG_2281_zpsp1o4cgtn.jpg.html?sort=3&o=9

Sorry Click for impinging, I was distracted by thoughts of heavyweight jugs!
I use 4 blocks of wood, split plastic tubing around the rods (the type welding wires come in). I did have some own made ring clamps but just used aluminium lagging straps the last time as they were to hand and they worked fine.

Regards, Al.
 
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And the game now is, what cam do I have?

I used a digital vernier, had the edge resting on the case & used the depth gauge & dropped it down to the back of one of the cam lobes & zeroed the vernier. Then I rotated the engine so the cam lobe was now at it's highest point & measured again.

I got a reading of 0.32" for an exhaust lobe, I think it's the standard 061084 cam??

It's not the most accurate way of checking the cam but it's the only way I have of measuring the cam!
0.332" Inlet and 0.322 Exhaust is standard. Regards, Al.
 
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A bit surprised that no one has mentioned the engine rebuild DVDs from the NOC with Mick Hemmings showing how to do things. He covers all these questions plus a lot of other stuff. I've stripped & rebuilt a number of different types of engines (most of them even ran afterwards :) )but I still learned a lot from it. There is also a gearbox DVD as well.
The NOC also sell an engine video with John Hudson - good to watch, but no where near as good as the Mick Hemmings one.
 

lcrken

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Some guys have suggested fitting the pistons into the bores first then fitting the pistons to the rods, can't see how you can hold all this together while fitting the gudgeon pins!!

Fast Eddie had a great picture of a piston holder, (see below). I can see this being useful while lowering the barrels down but it would be fiddly getting the rings to spring into the bores or is it easier than I think?

How about the use of ring compressors?
As a last resort, you could always just use the method in the service manual:)

Actually, I use ring compressors as in the picture, but I also use a plywood cutout to hold up the pistons, similar to Fast Eddies plastic plate. That does seem to work better than the two rods in the picture. The ring compressors I use are also a bit easier to remove than the style in the picture.

c41sjpgx2.jpg


Ken
 

click

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Appreicate all the replies.

As I get older, I've learned to ask before I lift a hammer!!, even if I think I know what I'm doing!! Is this wisdom:rolleyes:
 

click

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A bit surprised that no one has mentioned the engine rebuild DVDs from the NOC with Mick Hemmings showing how to do things. He covers all these questions plus a lot of other stuff. I've stripped & rebuilt a number of different types of engines (most of them even ran afterwards :) )but I still learned a lot from it. There is also a gearbox DVD as well.
The NOC also sell an engine video with John Hudson - good to watch, but no where near as good as the Mick Hemmings one.
Sure why would I get them when I have all of you ;) I'll get onto the NOC site & start ordering:) thanks for the reminder, I've been meaning to get them for yearso_O
 

baz

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The very best piston ring compressors I have ever used are 3" house drain pipe pipe plastic clamps from a DIY shop with a bit of 6mm studding and some wing nuts.
You can do them up as tight as you like ,tap the barrel down with a rubber mallet no problems at all.
I have used steel motorcycle type ones + car type ones but they don't come close to the gutter clamps for ease of use or for ease of removal, cheers
 

click

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The very best piston ring compressors I have ever used are 3" house drain pipe pipe plastic clamps from a DIY shop with a bit of 6mm studding and some wing nuts.
You can do them up as tight as you like ,tap the barrel down with a rubber mallet no problems at all.
I have used steel motorcycle type ones + car type ones but they don't come close to the gutter clamps for ease of use or for ease of removal, cheers
That's a great tip, I see a trip to the DIY store tomorrow :)
 

Mr. Rick

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Do the rods come up out of the case far enough to permit just fitting the wrist (gudgeon) pins?
If Jim were to fit the pistons/rings and ship them back inside the barrels, could they be pushed to the bottom, leaving the rings in the bores, and just enough to expose the holes for the pins, suspending the whole barrel + pistons assembly while fitting the pins?
 

comnoz

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Do the rods come up out of the case far enough to permit just fitting the wrist (gudgeon) pins?
If Jim were to fit the pistons/rings and ship them back inside the barrels, could they be pushed to the bottom, leaving the rings in the bores, and just enough to expose the holes for the pins, suspending the whole barrel + pistons assembly while fitting the pins?
Yes, and that would be the way I would assemble them.
I sell lots of rings to replace rings damaged by ring compressors. I just use my fingers. Jim
 

rvich

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Just trying to keep up here. So you aren't going to break open the lower end? Does that mean that you have studied the balance factor issue and are happy with it or that you are ignoring it?

Sorry to ask. But someone has to!
 

click

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Just trying to keep up here. So you aren't going to break open the lower end? Does that mean that you have studied the balance factor issue and are happy with it or that you are ignoring it?

Sorry to ask. But someone has to!
No need to say sorry, it's the main reason I started this thread so questions like this are asked, thanks.

I'm working on this with Jim at the moment, I'm going to check with Pete L. what he would normally balance a crank at for the Norvil 920 kit with Ford pistons. Since the chap that built my bike worked for Pete, its a reasonable assumption he would have used what Pete uses. It might just be the standard balance of 52%.
 
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Re assembly: What Fast Eddie says!

I have done it the same way multiple times - no drama at all.
 

click

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No need to say sorry, it's the main reason I started this thread so questions like this are asked, thanks.

I'm working on this with Jim at the moment, I'm going to check with Pete L. what he would normally balance a crank at for the Norvil 920 kit with Ford pistons. Since the chap that built my bike worked for Pete, its a reasonable assumption he would have used what Pete uses. It might just be the standard balance of 52%.
OK, I've been annoying Jim with a few emails back & forth with the piston weights etc. and he has worked out the balance factor based on a few assumptions and feels it should be fine and I'm happy with that.
 

click

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I see a paid trip to Ireland in your near future.
As long as Jim didn't mind being crated up and spending 2-3 days being shipped from the USA to Ireland, we would of course ensure he had some water etc.

I can put a hammock in the garage so he can be with the bike 24/7 I can loan him my tools, a large hammer & an adjustable wrench of the finest quality o_O

My hand is waiting to be bitten off :rolleyes:
 

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