The most likely reason that your cam and lifters went bad is that the
lifters were not hard enough. We hardness test ALL lifters that we use in
our engines, especially NEW ONES. In the last 2 years I returned at least
10 lifters to the TRF that were under Rockwell 50 hardness. I have also
returned many to Moss that were to soft.
Original lifters were always harder than 53 and sometimes they went as hard
as 57. I have received some new ones that checked at 19! The criterion
that we use is 50 to 53 for a stock engine with stock spring pressures,
54 and above for anything with higher spring pressures than stock. For a
full race engine with 135# on the seat and 225# or more at full open we sort
out sets that check at 56 and above. We also have all our cams ground with
tapered lobes to match the radius on the base of the tappets. The original
stock cams did not have a taper and that contributed to their early failure.
We have not had a cam or tappet failure that I am aware of in the last 15
years . Of course we always is Molybdenum disulfide assembly lube paste on
all tappets and lifters.
Regards, Greg Solow
-----Original Message-----
From: dames@parker.com <dames@parker.com>
To: Gregmogdoc@surfnetusa.com <Gregmogdoc@surfnetusa.com>
Cc: triumphs@autox.team.net <triumphs@autox.team.net>;
Morgans@autox.team.net <Morgans@autox.team.net>; twakeman@cruzers.com
<twakeman@cruzers.com>; slikdik@earthlink.net <slikdik@earthlink.net>
Date: Thursday, February 11, 1999 2:32 PM
Subject: Of Valve springs, Water pumps, Radiators and Such
>Further to your concern about proper springs, I recently installed three-
>part valve springs in my TR3A engine along with new tappets, push rods and
>a 280 degree cam ( and some other things). The springs tested at aprox.
>105# cold. Within 1500 miles both the cam and the tappets were destroyed.
>I've gone back to stock springs ( from Moss) which tested at 76 - 79# cold.
>At operating temperature, these values should degrade - - perhaps to aprx.
>70#. Time will tell if this setup will endure.
>
>I've also witnessed that the water pumps supplied by Moss can have two
>distinct sizes of impellers: one having a substantially larger surface area
>than the other.
>
>In Southern California, every element in the cooling system is important.
>I purchased a replacement original design radiator from Moss. It came from
>India. Per my order, this one did not have the hole for the hand crank.
>It didn't help my cooling problem. So, with the help of a local radiator
>shop we reconfigured the radiator - - -with a modern high density core but
>with the upper and lower TR3 tanks plus a modern neck and cap allowing a
>closed system and recovery bottle. Cap pressure is rated at 7#. With
>proper shrouding and the above elements in place, the engine which makes
>more power than a stock one, runs about 30 degrees cooler than before the
>changes. Oh yes, I also took off the original fan structure and added two
>electric fans. Overkill, perhaps.
>
>Dick Ames
>Triumph Register of Southern California
>
>
>
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