Making ready to run the engine, oil pressure tested and supercharger belts on to enable a proper check of the pulleys for the first time. The build stand restricted the access to the engine front pulley before and so we were unable to do a final test fit and align faces. Now we are ready to assemble the front cover complete with the front engine mount.
Here we are modifying the frame to now properly locate the front of the engine via the front mounting. As is often the case with very "clean" sided cast engine blocks of the period, there are very few places to mount a conventional build stand.
Last month, we had carried out a very temporary overview by cranking the engine over with the pulleys attached. But, this was with limited engine support only allowing a limited amount of trial pulley alignment and to check the operation of my new oversize dynamo pulley. It also gave us an opportunity to prepare a special woodruff key to overcome the fact that during nitride treatment, the keyway in the crankshaft had closed by several thousandths of an inch along with the flywheel bolt location holes in the rear crank flange (see previous posts re these issues). Here we are just giving a final dress to our previously made "stepped" key before fitting to the front engine pulley and crank.
Of course even on this home stretch, there are always small problems. The carburettor piston had a very dull piston closure sound when lifted and dropped as if the needle was catching the jet. Thinking it would be a simple case of releasing and centralising the jet block, I was a little unsure why the block seemed to bind (from experience they normally slide into position very easily). Removal of the jet block revealed the problem; the two small soft jet glands sit in small brass cupped washers onto which the pressure spring bears. Except, on this unit the washers were missing and the soft glands were distorted and bound up inside the spring, stopping any form of side adjustment. Not wanting to delay even further, luckily we had another SU on the back of the bench enabling me to "borrow" the washer as well as borrow a replacement fibre vent washer for the top nut of the float chamber as this washer was also missing.
Whilst in this area, I had made a new banjo for the fuel feed, the unit is quite large and bulky for this application which has limited room. By making a slimmer unit of a slightly altered shape, we have quite a nice arrangement.
But.....(there is always a but when you change a design!) I hadn't quite made it deep enough by about 010" resulting in a fuel weep. To correct this I machined an extra thick aluminium washer to suit. I will make some spares of these non std washers for the car's toolbox.
As I mentioned, this last phase has been the first opportunity to wholly test fit the front pulley and the front housing. Unfortunately, I made the 5/16" pin that passes through and retains the bottom of the chain tensioner, a little too long. Again I was not keen to remove the tensioner at this point and so I trimmed it to length with a junior hacksaw and dress with a file in position. Lots of judicious packing of rag and a strong vacuum cleaner keeping the swarf out of harms way.
We had spent a surprising amount of time setting the valve clearances for a final time before the run. It is important to make sure they are secure when complete to avoid any risk of migration. Whilst I am sure it would be ok, I don't wish to risk any blowback into the charged manifold from an unseated inlet valve.
It is getting late evening here in the workshop and there have been a few late nights to get this engine finished. However, that has not stopped the Christmas spirit coming over from the kitchen and a Christmas tree bedecked front room as you can see by the non health and safety addition on my bench... thank you Bryony! Mulled wine... Cheers!
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