Crankshaft end float

Engine Oily Bits, Ignition, Fuelling, Cooling, Exhaust, etc.
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Brian
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#1 Post by Brian »

I am just rebuilding my PI engine and I have about 8 thou end float with STD thrust washers. Should I put a +5thou washer or leave it? I can\'t decide!
Thanks
 
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Alec
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#2 Post by Alec »

Hello Brian, <br>
<br>
I don\'t think that 0.002\" over spec is a problem. You could also take&nbsp; 0.003\" off the back of you +5 bearing to be spot on?<br>
<br>
I would go for 0.008\" personally.<br>
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Alec<br>
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Alan Chatterton
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#3 Post by Alan Chatterton »

I would rather have it under spec and put the 5thou oversize one in, less crank movement, less chance of them falling out!
But that\'s just me!
Rgds
Alan
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Alec
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#4 Post by Alec »

Hello both, <br>
<br>
I think I would be concerned about oil flow at the tighter setting, especially when expansion is taken into consideration. <br>
I did pin my bearings when I built mine so that could be an option if you like?<br>
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Alec<br>
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David Withers
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#5 Post by David Withers »

Hello Brian,
With STD thrust washers, the end float is within spec at 0.008\", but fitting +5 thrust washers will bring it right out of spec at 0.003\", i.e. half the minimum specified float.
The 0.006 - 0.008\"&nbsp;limits were specified for a reason and 0.003\" is far too little in my view.&nbsp; I would keep to&nbsp;STD size or, as Alec said, get some +5 washers ground down to +2 if you want to take the end float to the allowable minimum.&nbsp;
I assume the tight limits on the 2.5 are to avoid the crankshaft hitting the block due to&nbsp;the longer crank throw and the 25% heavier clutch end loading. I\'d be surprised if there is&nbsp;a great risk of&nbsp;the thrust washers falling out on the 2.5 engine until beyond the 2000 maximum of 0.014\" end float, but perhaps someone will know different.&nbsp;
Incidentally,&nbsp;one of my jobs as an apprentice 45 years ago was to grind thousands of +0.003\" thrust washers to STD because our supplier had run out of STD washers for our&nbsp;diesel engine&nbsp;production line.&nbsp; I had to hold 16 at a time on a magnetic base with, of course, the non-magnetic bearing face downwards.&nbsp; There were quite a few&nbsp;incidences of thrust washers flying through the air when I tried to take too much off in one pass!&nbsp;
David.
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Brian
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#6 Post by Brian »

Hello!
Thanks for the replies. I think I will stick with the 8 thou end float and see how it goes. I would be reluctant to tighten up too much as I don\'t know how much expansion takes place. I also asked Chris Witor what he thought yesterday and he advised me to leave it at 8 thou too. Thanks for the advice, it has certainly put my mind at rest!
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valencia
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#7 Post by valencia »

I had a similar problem on my 2000.&nbsp; As there were two new thrust washers in the kit I decided to use one new and one old washer.&nbsp; This reduced the end float towards the bottom of the range.&nbsp; This was 12 years ago, it has not caused a problem.
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