[TR] Low Oil Pressure and Engine Noises

John & Pat Donnelly pdonnel1 at san.rr.com
Sun Sep 6 17:28:02 MDT 2009


OK, I'm about to go back underneath the car and check the rod bearings, but
have some questions about the mains. The engine is still in the car. Is
there a trick to taking them out? Can I just remove the main caps and rotate
the top one out? I seem to recall there was a notch on one side of the
bearing that matched the cap/block so they wouldn't spin. Is re-install the
opposite of taking them out?

And, if the bearings are oversized isn't there usually some sort of stamping
on them (eg .01)? It's been a few years since I rebuilt it and I forgot what
went in there.
Johnnie

-----Original Message-----
From: Michael Marr [mailto:mmarr at notwires.com] 
Sent: Sunday, September 06, 2009 2:10 PM
To: Peter Ryner; Randall; 'John & Pat Donnelly'; triumphs at autox.team.net
Subject: Re: [TR] Low Oil Pressure and Engine Noises


----- Original Message ----- 
From: "Peter Ryner" <pryner at verizon.net>
To: "Randall" <tr3driver at ca.rr.com>; "'John & Pat Donnelly'" 
<pdonnel1 at san.rr.com>; <triumphs at autox.team.net>
Sent: Sunday, September 06, 2009 3:26 PM
Subject: Re: [TR] Low Oil Pressure and Engine Noises


> Randall is right on.  It is false economy (from my early repair manuals) 
> not to open the bearings and at least check them out - I would just 
> replace the rod bearings them as a matter of course.  You may not have any

> damage from the debris in the oil pump, but if you've had low oil pressure

> you may have damaged the bearings anyway.  The main bearings are a little 
> more problem to change with the engine in the car, but I would change them

> if there is any wear.
> Not a bad idea about the pump shaft too.
> My $.02 input
> Pete

When I first got my TR3A I had low oil pressure.  I dropped the sump and 
found similar damage to the oil pump (though not as extreme as yours).  I 
checked all the main and rod bearings and found that the #1 crankpin bearing

shells had a piece of tramp metal embedded in one of them.  Apparently, this

piece of metal had passed through the pump, along the oil gallery, through 
the front main bearing and through the drilling to the first crankpin, 
whereupon it stuck and scored the crankpin.  I dressed the crank pin with a 
stone, to remove the high spots, and then with crocus cloth, and replaced 
all the big end bearings.  The car ran fine for another 15 years, which is a

testament to the bullet-proof nature of this engine, if nothing else.  So, 
check the mains and big ends - those broken pieces could be anywhere!

Mike

Mike 


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