At 10:33 PM 12/27/96 EST, Jack I Brooks wrote:
>Barry (and anyone else who can help),
>
>I have been a little slow in getting into my engine but you were right.
>The knocking noise, I thought were bearings, was really an aftermarket
>water pump. When I disconnected the fan belt, the knocking noise went
>away. It could still be the generator, but I am virtually sure the noise
>was not coming from there.
>
>So far taking the fan belt off has been the most difficult task I have
>found on the TR3. I elected to check out the bottom end anyway, as I was
>concerned about the low oil pressure at hot idle, 15 psi and the
>potential for a really worn bottom end.
>
>So far I have:
>
>Checked out the oil pump. It is well within specs on the gaps between
>the impeller and the concentric and the concentric and the housing. The
>end float is a little loose. I will probably lap the case to bring that
>in. I had to do that on my Norton motorcycle, different style pump, same
>problem.
>
>Thrust bearings are 0.011. Spec is 0.004 to 0.008. The bearings looked
>a little worn on the faces. One had some surface erosion which went
>radially outward through the entire bearing face (white metal only). I
>will be ordering standard thrust bearings as well as trying to figure out
>how I can measure the gap to know if I need oversized.
>
>Pulled off the center main bottom and plastigaged it - 0.003 in two
>places, and the bearing looked good. It is a little loose, but ok for
>now.
>
>Pulled the number two big end, I have not plastigaged it yet but it
>looked great. I will probably do all four before I close it up.
>
>The engine is still in the car. Since the center main bearing takes the
>most abuse/wear (my assumption) depending on just how hard it is to pull
>the front and rear bearings, I may not check them out. The car was
>reputably in top notch shape when I bought it and it does seem to be
>pretty solid.
>
>My request for you is, what is the best way to check out the other main
>bearings? In an earlier correspondence you told me you could provide
>more detailed info if I ended getting into the bottom end. I am working
>with an original TR2 manual and a Haynes manual, but the directions for
>doing the work with the engine in the car are very sketchy. My biggest
>concern is how does one get the top half of the bearing shell out without
>pulling the crank?
>
>Also, is silicone seal a good substitute for shellac soaked felt?
>
>Any help/advice I can get would be greatly appreciated.
>
>Thanks.
>
>Jack Brooks
>Hillsdale, New Jersey
>1960 TR3-A TS69032L
>1974 Norton Commando Roadster
>
> Hello Jack
Re your concern about low oil pressure. l5 lb sq in is OK for 700 rpm on
an engine in which the oil is hot. It takes about 30 min running for the oil
to get hot. There is a oil pressure releif valve on the filter head assy. ,
The spring in this assembly may need replacing. It also has an adjusting
screw for adjusting pressure. Usually low oil pressure means worn rod-main
bearings. You are at the clearance limit on the bearings you checked. There
may be flat spots on the journal that you cannot check with the crank in the
engine. The combination of these two conditions may give you low pressure.
If it were my engine, I would replace the main and rod bearings with
standard units with the crank in the engine and the engine in the car. I did
this to my car 15 yrs, l5,000 miles ago. This is an easy fix , but I would
not expect more than 30,000 from it. Remove the main bearings and the
crank will be suported by the tranny and the timing chain. The upper bearing
shells can be rolled out by using the lower shell to start it. The front
bearing cap has a aluminium block between it and the oil pan that must be
removed. There are two screws that hold the cap to the front plate that are
easy to overlook. The downside to this fix is that it is dificult to prevent
leaks, but if anyone is fussy about oil drips, then you will not be happy
with a 50's car anyway.
Re; thrust washers, My book shows ,004 -.006 play. Order std and
oversize to come up with the right combo. ,005 is available, maybe others,
try TRF. You my need to use the oversize on one side std on the other.
Check the end float by moving the crank untill it seats agin the thrust
and check the gap on the opposite thrust with a feeler guage.
Put Vandervell bearings in it.
Sam Haynes TR3 original owner
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