I would be very careful with wet-or-dry. It can leave microscopic
particles behind. Get the standard very fine emory cloth, which is
actually used by machine shops for this very purpose.
On Thu, 28 Sep 2000
CarlSereda@aol.com wrote:
>
> Bruce - you've lost your mind so might as well go for it
>
> if it were my crank I would buy a small very fine cut file to take down the
> nick protrusions to the level of the surrounding bearing surface. Then I
> would take the finest 'wet and dry' sandpaper like 600 grit and cut a 1"x3"
> strip and wrap long ways onto a piece of glass or other VERY FLAT small panel
> (would not wrap the outer sides around the panel as that would create high
> edges).
> I would get my face right in there with good light and carefully address the
> areas in an attempt to make bearing surface an even plane and finish. I would
> use light weight oil to lubricate the work. It seems critical not to lower
> the height of surrounding bearing surface. I would be hesitant to use crocus
> cloth because it conforms to the surface. You want to lower the protusions
> but not alter the low spots. A firm flat surface will help you hit the high
> spots and leave the lows untouched.
> Flooding it with WD 40 seems uneccessary unless you making a big mess.
> Dragging the car to break in the motor seems a waste of time to me.
> The bearings will settle in how they're going to settle in within the first
> ten minutes of running - and probably be ok - you may not get as many miles
> on these bearings .. but then again maybe you will get 30,000.
> While you're at it: big-end rod bearings go out even faster than crank mains
> I believe- you may want to refresh those while you're in there..and you won't
> need bang 'em up as they're easier to get out!
>
> no guarantees of course - good luck -
>
> Carl
> '63 TR4 since '74
>
> >>Subject: Decision on TR7 Bearings from Hell
>
> Well, with the posting of this email, half of you will think i have lost my
> mind, and the other half will be saying "go for it!"
>
> After a closer look at the scratches and burr on my TR7s crankshaft, I'm
> going to rely on my trusty Dremel and yards of Crocus cloth to smooth out
> these blemishes caused by my carelessness, instead of pulling the crank which
> I have neither appropriate space or cash to do, but would probably end up
> being a heck of a lot quicker.
>
> What I do have is plenty of time and sweat-equity to put into the project,
> and for you who are still interested, a couple of additional questions:
>
> 1. I finally got the #1 bearing out by taking the camshaft caps off and
> raising it enough to reduce the chain tension. The upper bearing slid right
> out. My question is whether the chain is suppose to be so bloody tight, and
> is there an adjustment I should be looking for?
>
> 2. My strategy is to clean up all the scratches and burrs, then spray a
> couple of gallons of WD40 over everything to clean out any grit, then put in
> some extra new shells on the bearings that were scratched, turn the engine
> over several times by hand, and then take the caps off again to see if any
> scratches appear on the shells. What do you think?
>
> 3. After I reassemble everything, including brand new bearing shells, I
> thought I would leave the sparkplugs out, and pull the car in gear to help
> the engine get "broken in" without the heat and pressure of actually running.
> Maybe pull it for a couple of miles, then replace the oil and filter. But
> then I thought maybe this would cause accelerated wear because the engine
> wouldn't be running at its normal temperature, so the oil might not be as
> fluid. Thoughts?
>
> After re-reading all of the above, I can't believe the effort I am about to
> go through. But there's something about the challenge that is irrestible.
>
> Of course, just to be safe, anybody got a spare crank they don't need?
>
> Again, many thanks for all the comments and advice.
>
> Bruce
> 1980 Inca Yellow TR7 5-speed convertible
> Chapel Hill, NC<<
>
James A. Ruffner
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