Jeff,
Plastiguage is used to check bearing clearances due to the tiny values here.
I believe the green color is used for the smallest values (check with a
jobber). On the engines I have worked on, the clearance for main & con
bearings tend to be in the .0005 - .0020 inch range. Check a manual. We're
talking less than 2 thou here!
Basically, you place a strip on the journal. torque the cap. Carefully
remove & compare the width of the crushed plastic with the guage on the
pack. Do not rotate!
As for the gasket - never heard of one.
Good luck!
Fred Kuzyk, MSCCC Past President
Roundel Records MP3 music site:
http://www.geocities.com/SunsetStrip/Bistro/9044/index.html
My MSCCC Morgan site:
http://members.xoom.com/msccc/
Holy Smokes & Southern Ontario Cigar Society site:
http://members.xoom.com/holysmokes/
----- Original Message -----
From: Jeff Webster <carfindr@tiac.net>
To: <cobmeister@zianet.com>
Cc: <Morgans@autox.team.net>
Sent: Saturday, July 03, 1999 4:56 PM
Subject: RE: Con Rod Bearings- HELP!
> Well, I can now tell you that although the pistons are in the wrong
> cylinders, it is only the caps on rods 1 and 4 that are interchanged. The
> chap responsible for this abortion by the way, is RICHARD SMITH at
> IMAGINATION ENGINEERING in ORLANDO, FL.. I tell you his name so you may
> avoid the guy and his business. He has lied straight faced to me
repeatedly,
> and I have proof. Triumph and Morgan owners in the Florida area DO NOT USE
> THIS GUY - HE'S A COWBOY.
>
> Any way, life goes on. This is a TR3 engine , I use 20-50 oil. Supposedly,
> the head was pulled, valves etc done, pistons removed, new rings fitted
and
> cylinders honed. The connecting rod bearing shells are still silver -
there
> is some scoring and scuffing, but not through to the copper. There were no
> shims used.
> The oil pump rotor actually had 15 thou clearance - 5 thou too much, so
I'll
> replace it. The crank is std. and has not been ground before. The car was
> not smoking, or steaming. Only a very small amount of coolant was getting
> into the oil and the car didn't run particularly hot, around 190-200
degrees
> on a hot day.
> I am not familiar with using plastigauge. What is the accepted tolerance
for
> connecting rod bearings? And what color plastigauge should I buy? Also
what
> is a 'figure of eight' gasket?
>
> Regards,
>
> Jeff
>
>
> Colin wrote:
>
> "Hey Jeff,
>
> Sounds like you may have some troubles, alright.
>
> I don't recall you saying what engine you have but I seem to remember it
> being a TR4.
>
> I take it the DPO told you that the engine had been overhauled.
>
> The oil pressure is somewhat low but not horrible. 50 lbs. at speed and
> 15 at idle at temp is not great but also, IMHO, not bad enough to rate
> any rebuild effort, particularly if funds are tight. You should be
> running a single weight (not multi-viscosity) oil, I would imagine you
> are using 30 weight and you might want to change that to a heavier
> grade.
>
> It sounds like you have a blown head gasket or cracked head but you
> should have been aware of that from smoke/steam... You did not say that
> the car has been run really hot. You did not say that you have been
> seeing oil crawling up the dipstick... If you are not seeing these
> things, and funds are a consideration, you might try adding some
> Barr's-leak, Stopleak, or something like that to try and plug the hole.
> (Many people do not like to use these products, saying it just delays
> the inevitable, but I know of cars that have run for many years with
> these products.)
>
> I think the seepage you describe could also result from a bad (or
> improperly installed) cylinder sleeve.
>
> The bearing problem sounds much more serious in the short term. The
> mismatched caps could definitely cause your knock and if it is knocking
> then you probably are looking at doing a real overhaul including turning
> the crank. Are you sure the caps are mismatched? Remember that one way
> to mark them is with a nail punch, making one dot for number one, two
> dots for number two, and so forth. Were shims used on the caps?
>
> If you are sure they are mismatched you should definitely pull the caps
> and inspect for damage to the crank. You may need to have it reground.
>
> Whether to swap the caps around to make them "right" is a tough call. If
> the wrong caps are installed, maybe the DPO had the engine "line bored"
> to make them match up (sorta). Such a procedure would not make any sense
> but if that happened, then swapping them back will lead to more
> problems. I guess my inclination would be to put them back like they
> should be, using a lot of plastigage to make sure they have the correct
> clearance. I assume you will be installing new bearing shells.
>
> It sure sounds like the DPO pulled the pistons and just threw all the
> parts in a box somewhere... Then just pulled parts out randomly to
> reassemble. Hard to believe that anybody who would undertake the job to
> begin with would be dumb enough to do that.
>
> Have you established that this is the original engine? I seem to
> remember that it isn't and if not, you may want to look around for a
> used engine.
>
> I am sorry this happened to you."
>
> --Colin Cobb, Las Cruces, NM, USA
> '66 Plus 4 Four Seater
>
>
>
>
>
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