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  #1  
Old 23-06-14, 11:34
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Private_collector Private_collector is offline
Tony Baker
 
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Location: Wide Bay, QLD, Australia.
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Default Vacuum testing of valve sealing, etc...

That's pretty cool, Mike. Wish I had thought of it.
I admire his quest for perfection.

Regarding Honing
Just ordered a 320 grit Flex Hone of 3.25" size. That is, it can hone up to 3.3" bore, while still having sufficient compression of the hone surfaces to do the job. What really sold me on these is that they indicate their hones are suitable for finishing of a bore where you do not want to go oversize as a consequence of the honing. That, plus the self centering ability of the hone. Also discovered you can use a range of oils with the grit I have chosen, including standard engine oils. Yay! Although grits of 600 (and over if special order) are available, 320 grit is recommended for my application.

Bob, i'm downloading and reading several PDFs relating to use of Flex Hone, right now :-)
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Ford CMP, 115" WB,1942 (Under Restoration...still)
Medium sized, half fake, artillery piece project. (The 1/4 Pounder)

Last edited by Private_collector; 24-06-14 at 08:10.
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Old 23-06-14, 13:16
Lynn Eades Lynn Eades is offline
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Just as important as any other aspect of the task is the cross hatch pattern. A 60 degree cross hatch is required. This is achieved by the combination of the speed of the drill (hone driver) and your up and down movement of the hone.
Did your new block come with pistons (I forget what you did) or are you sizing the bores to suit the pistons? I would recommend you have it done proffessionally. The piston to bore clearance is very important to a long (engine) life, as is cleanliness. A thorough wash out with hot soapy water after the hone, so that white rags show no marks,then dried and liberally oiled straight away. Along with absolute cleanliness, there is a lot to get right. Much money invested so far. Consider carefully.
If you have to size the bores, the "sheep dag" hone is not the hone to use. It is however good to finish the surface of the bore
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Carrier Armoured O.P. No1 Mk3 W. T84991
Carrier Bren No2.Mk.I. NewZealand Railways. NZR.6.
Dodge WC55. 37mm Gun Motor Carriage M6
Jeep Mb #135668
So many questions....

Last edited by Lynn Eades; 23-06-14 at 13:32.
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  #3  
Old 23-06-14, 16:40
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Tony Wheeler Tony Wheeler is offline
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I'm not quite following here. Why does the block need honing? It's a brand new block, it should already be hone finished to 3.1875 inch. That's what the pistons are designed for, they should fit straight in. Clearance should only be about 1 thou, they'll be sloppy if the bores are honed out further.

If the bores need resizing for some reason, then it should definitely be done professionally as Lynn says. However I don't see why it would be necessary.
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Old 23-06-14, 22:10
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Tony Baker
 
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Block does not need resizing. I am simply doing a final finish to apply the cross hatching better than it is right now. I dont consider it sufficient at present. With the grade of the hone and time spent in each cylinder, nothing will be made 'sloppy'. This is confirmed by the manufacturers information, and advice from 2x mechanics who have inspected the block is that the final hatching has not been done on the cylinders. I believe this was left for the person doing the assembly, rather that at time of manufacture or machining.

The link I posted yesterday will show the specific info on the hone grade I have purchased. Also, a number of youtube videos on its use confirm my use is appropriate. I will give no more than 10 seconds total in each cylinder.
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Ford CMP, 115" WB,1942 (Under Restoration...still)
Medium sized, half fake, artillery piece project. (The 1/4 Pounder)

Last edited by Private_collector; 23-06-14 at 22:41.
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  #5  
Old 24-06-14, 07:58
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Tony Wheeler Tony Wheeler is offline
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Very interesting Tony. I wonder if it has anything to do with being a military block, which would be going through Army workshops. Or is this standard practice for all new blocks purchased bare? I've only ever fitted rebored blocks, and they've always been finished to spec. The only time I've used a hone is for ring jobs, to deglaze the bores and remove the lip. Afterwards I check the piston clearance to make sure it's still acceptable.

It's quite good fun I think you'll find, although if you have an old block it would be worth practicing on, to get the 60 degree pattern Lynn mentioned. Look forward to more pics as the job proceeds.
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  #6  
Old 24-06-14, 12:12
Lynn Eades Lynn Eades is offline
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Yes, Tony.W., I would recommend a practice. (sheep dag hones are great! They make any bore look good)
Pistons in a set, are not always the same size. In a factory assembly situation the standard pistons used to be graded for size (and or weight) so that an engine might end up with a set about the same. Hopefully the pistons in your set, have been graded (I would expect them to be these days) I would though, measure them.
Tony you will no doubt be setting up a financial relationship with an engine reconditioner for at least the sizing of your gudgeon (con rod) bushes, I am sure you can pick up some expert guidance from him/her (you never know) at the same time.
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Carrier Armoured O.P. No1 Mk3 W. T84991
Carrier Bren No2.Mk.I. NewZealand Railways. NZR.6.
Dodge WC55. 37mm Gun Motor Carriage M6
Jeep Mb #135668
So many questions....
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  #7  
Old 26-06-14, 11:04
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Tony Baker
 
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Why on earth would I need someone to mess with the con rods & piston pins?

New pistons, new pins, new con rods with bushes insitu.

Following the test shown in factory maintenence manual, everything fits perfectly.

Fully expect to call for help with some task or another, but wouldn't have thought they should need to muck around with parts which fit properly already.

Funny, for a job that anyone is supposed to be able to do, sure sounds like a lot of things the experts are needed for.
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Ford CMP, 115" WB,1942 (Under Restoration...still)
Medium sized, half fake, artillery piece project. (The 1/4 Pounder)
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