It's raining cats and dogs here. The MGA is sitting in the parking lot
getting more soaked by the minute. At least the weather protection gear is
attached this time. I can hear the floorboards swelling from here.
I found the oil leak last night. The external pipe was leaking where it
attached to the new Moss spin on adapter. I had used new copper washers
there but I took the pipe off again to prime the oil pump after the
rebuild. I tightened it a little more and we'll see if that fixes it. If
not new washers will be on the next parts order.
A couple of notes on the freshening process. Two of the hardest things to
do were to remove the rear tranny seal and to remove the needle bearings
from inside the tranny laygear. The rear seal was an assembly of rubber
seal and felt shield inside a steel housing. Using heat, a vice, a prybar
and a bigger hammer, it finally let go. The new one is just a straight
seal and seems to be holding oil so far. On the needle bearings, I worked
for an eternity to get those little internal spring clips out for the two
outer bearings. My methods were not conducive to removing the second inner
bearing from the front however so after some judicious inspection of the
bearing and my soul, the old one was left in while the two outer ones were
replaced. The tranny is quieter now so it must have helped. I used a new
layshaft, of course.
One area where I deviated from stock was in the combustion chamber. I took
my trusty Gibbonizer (aka Dremel type device) and carefully broke the sharp
edge around the combustion chamber. I also rounded the upper edge of the
"widow's peak" in the chamber such that tip was more or less spherical. I
never had any run on problems before but even with the idle higher and the
temps hotter after the rebuild, it still dies immediately after the
ignition is cut. I also looked into opening the ports a bit but the
Gibbonizer is just too slow for this type of work. I was on a very tight
schedule to get the A back on the road so no port work was done.
The A runs about 10 degrees warmer now than before. It used to run at
160-170 with occasional forays up to 190-200 during of after a hard run.
Now it runs at 17-190 most of the time. It has gotten to 210 once but that
was when I didn't have the radiator cap on so maybe that had something to
do with it. Or maybe it was running 80 down the freeway. Who knows.
The oil pressure with the Valvoline is acceptable but it is still a little
lower than before the rebuild. I am going to run it longer and see what
happens. Again, this is really only a concern after a long run on a freeway
on a hot day. If it bothers me too much I'll add an oil cooler. I may
switch to Mobil 1 15-50 after 1500 miles or so to make sure it is broken
in. I have had motors (not MG) that run much lower oil pressure in the
past and they ran forever.
The idle is a little rougher with the new NWI mild street performance cam.
The A seems a little flatter under 2500 rpm but it definitely has more pull
above 3500. Also it runs more free at cruise. Before 4000-4200 was a
comfortable cruise rpm. Now will run up to 4600 with no feeling of labor.
It has more passing power now too. All in all I would say that the cam is
a good choice although I won't be drag racing any Miatas. Geo's and
minivans are fair game though.
Regards,
Bill Eastman
61 MGA presently getting watered
PS I spent about 2 hours in the A Saturday. It was raining but was still
a good drive. Dick we miss you. Ray also.
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