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1991 cc rebuild

To: "'wallaces@superaje.com'" <wallaces@superaje.com>, "'triumphs@autox.team.net'" <triumphs@autox.team.net>
Subject: 1991 cc rebuild
From: "Westerdale, Bob" <bwesterdale@edax.com>
Date: Tue, 5 Sep 2000 13:55:11 -0400 charset="iso-8859-1"
Jim-
Uh Oh....
        IF the goal is to do this job with the smallest possible  $ bill at
the end, just hit the delete key now.  If the goal is to build a reliable,
strong motor, maybe the following might help...
        First, clean ALL the crud off the pistons, liners, crank, and rods.
Put 'em all in a coupla boxes and prepare to  visit the local reputable
engine shop for some measurements.  Do a little research first, get the
dimensions and tolerances for the bore, journals, piston OD, ring width,
small end bearings, etc.   After determining the Engine shop guy has a good
rep, get his opinion on how things look.   He makes his living machining
stuff, so he will be inclined to tell you that his services are desperately
needed, so keep your "BS detector" on the highest sensitivity.  
        Unfortunately, something had gone way wrong in the engine's most
recent  life,  and to optimistically throw in rings and a set o' big end
bearings would be compared to running your cash through a paper shredder.
Something trashed the top rings, perhaps VERY high mileage, but more likely
a previous rebuild did not provide adequate ring end gap OR put new rings on
old pistons, installed in worn ( even though honed shiny), uneven liners.
The bore does not wear evenly, and forcing new rings into a bore that has
non-cylindrical dimensions will be a most disappointing waste of time and
money.  Pretty much the same news for the crank, too.  The damage to the
journals will do a nice job of chewing your new bearings up, and the
hammering that will develop will remind you of an old sewing machine.  You
can't easily pull the crank out of a 3 engine with the block in the car, so
it is best to do it right the first time. Regrind! 
        IF the liners need boring, ( and I'll bet you a beer they do...),
then you will undoubtedly need new pistons and rings.  Whether it is cost
effective to pay the machine guy to do the set up for boring liners outside
of the block is a close call.  A new set of pistons and liners runs around
$4-500  and avoids the pitfalls of trying to hold the old liners accurately
while boring. ( not a trivial job...)  Be sure to balance the parts,  from
harmonic balancer through pressure plate. How are the valves? guides? etc...

        Hope this isn't too discouraging, ($$$) but as they say, 'Ya get
what ya pays for'!
Regards,
Bob Westerdale
59 3A  TS36967E  
              


Preamble:
Well it rained this afternoon here and so I worked in the garage, 
ostensibly cleaning up a bit, when my 3a engine called out to me: "take me 
apart even more!" Out came the pistons and liners, and what a large pile of 
crud befell my eyes. 3 decades of evaporated coolant is a sorry sight. 
Found some stuff that has generated some questions; hope some of you can 
assist:

Meat:
a) How typical is it to have the top ring broken into many small pieces on 
all four pistons? None had the second or oil rings broken, albeit some are 
stuck "closed".
b) No scoring on pistons or liners (whew!) but there is some "surface rust" 
near the tops of the liners where the pistons weren't for ~30 years. If 
they look good after honing, will regular sized rings suffice, or are there 
special ones?
c) The crankshaft has just-detectable-with-my-thumbnail ridges. I figure 
they're well under 2 thou, by feel, and it's only at the top where it takes 
a pounding, between the two oil holes, and it's only on 3 cylinders. (Yeah, 
I know, don't slag me on my measurement techniques, please)
So, will polishing be enough? I am not familiar with polishing.... It just 
seems like taking off ten thou. would be a waste, not only of money if it's 
unnecessary, but of thickness.
d) Copper figure 8 gaskets came out. I just got replacements the other day 
from BFE and they look like aluminum. Is this right? It doesn't seem like a 
great idea to be mixing aluminum and iron like this. I am not to thrilled 
with the idea of replacing them anytime soon, that's for sure.
e) Are pistons dishwasher safe? If yes what detergent is recommended?

All help appreciated!
Tx,
Jim

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