Deci$ion$ and Con$equence$
By Corky Guenther
October 21, 2013.
To review, it started with a crease in the left front wing which precipitated a full repaint and interior refurbishment. Delays meant we reluctantly decided we couldn’t meet our original schedule to attend the NEMGTR 50th Anniversary GOF in October, 2014.
This prompted another three self decision – you remember selves 1, 2 and 3 - with lots of consequences. The oil pressure had been diminishing gradually and since the car was almost completely disassembled, it seemed like the opportune time to rebuild the engine. That’s what we did (the decision). The consequences follow. With more help from Dave Ahrendt, David Poe and Dean Sprague the engine, already removed, was disassembled and taken to Allan Powell’s machine shop for evaluation. The crankshaft was OK, requiring only a polish and new bearings. Pistons and rings required replacement. A cylinder rebore increased the oversize from .100” to .120” and fortunately, there was just enough meat in the block to not require sleeves.
The head was refurbished with a new rocker shaft and bushings. Valves and guides were OK to reuse, with a valve regrind and new seals. New valve springs provided with the roller cam were installed after Allan worked some magic on the spring seats. The oil pump was rebuilt, with the body and cover resurfaced and new innards installed.
The plan was to use the original flywheel but have it lightened. However when setting up to machine it; Allan discovered it was cracked. So another delay and a search for a replacement ensued resulting in the decision to install a new lightweight steel flywheel. The clutch pressure plate was checked, and a new disc obtained. Everything was balanced and all of the pieces were gathered at Dean’s garage for assembly - he’s got the most tools.
All was going so well - pistons/rods, crankshaft, camshaft, oil pump and then came the distributor. It stopped about ¼” shy of fully seating in the block, bound up tightly on the camshaft drive gear. When the distributor shaft with new gear was clamped to the cam drive gear with the pump shaft vertical to the cam viewed from the camshaft end, the pump shaft axis was off of perpendicular with the camshaft axis by about 3 degrees. The three axes should be orthogonal. Several days (delays) later after sending the new cam back to be checked, ordering a replacement distributor gear and shaft assembly – twice since the first reorder produced an assembly duplicating the original replacement. Reinstalling the old cam, new cam, old distributor shaft/drive gear, new distributor drive shaft/drive gear assemblies (3) in numerous combinations, the problem was confirmed. The new drive gears for the distributor had been machined wrong (2 of 3). With the problem resolved assembly continued.
Did I mention that we were working against another deadline? The Fall NEMGTR GOF again. This time in Strasburg, PA with visits to friends in MA and VA. No worries, all was going well. We painted the assembled engine, trailered it to our house and installed it in the car, mounted the radiator, added fluids, spun it on the starter to get oil pressure and fired it up. Ran like a top.
Now it was time to install the front of the car. Wings, valence, headlights, badge bar, fog lights, wheels and tires – you get the picture. Time was marching on but we were still OK. Once the car was assembled (sans bonnet), break in driving started. The goal: to get 500 miles logged and remove the break-in oil. After 500 miles, I removed the valve cover to re-adjust the valves. That’s when I discovered that the rockers & valves had gotten very hot. After Selves 1, 2 and 3 had exhausted most of the considerable vocabulary acquired in the Navy; investigation revealed that the rocker shaft was not getting any oil. The cause? It turns out that it is possible to install the rocker shaft backwards. Fits very nicely and looks just fine. Good oil pressure too, just no flow.
As a result, the head went back to the machine shop for analysis. New rocker shaft, rocker bushings, one exhaust valve and new stem seals completed the list. All things considered, not too bad though it really did a number on the time line. The head was retrieved from the machine shop on August 10, Allan having turned it around in a couple of days after receiving the new parts. Then the race to reassemble everything, change the break-in oil, put another 500 miles on the engine, deal with unseated rings/glazed cylinder walls (Marvel Mystery Oil soaking followed up by several runs up to 4500 and down) a change to regular oil, install the bonnet, aim the lights and a hundred more details. One more return to Jimmy’s for a final hand polish and we were ready to head for New England with a couple of days to spare.
October 13, 2015
Eight days shy of 2 years and a bunch of decisions and attendant consequences from the original incident, we departed. We did decide to rearrange our schedule, visiting our friends in MA and VA after the GOF rather than before but we made it. Selves 1, 2 and 3 sighed with relief. Priscilla was elated (objective).
