After much head scratching and gnashing of teeth I decided that I needed to delve deeper in to the engine to find out what was going on - I couldn't get even the slightest bit of life out of it and was becoming increasingly frustrated, as it turned out it was just as well it didn't start as there was no oil pressure, in the 7 months or so since I built the engine the oil had drained from the pump and no oil was getting to where it needed to be. I had to remove the distributor and reprime using a screwdriver blade in my electric screwdriver - the drive for the oil pump comes off the bottom of the distributor. It's kind of cool in a way because you can build pressure without running the engine but it is a lot of fafffing about. To get oil to the pump I removed the oil filter and fitted a pipe with a 90 degree bend to the bit the filter screws on to and filled the pipe with oil so the level was above the pump dody. The normal way to do this is to take the pump to pieces, stuff it with vaseline then put it back together. I figured my peculiar method was worth a shot - it was, after about 10 seconds of spinning the pump I suddenly felt the load on the drill, the revs dropped and my oil pressure gauge showed about 15-20 psi. I let it run like that for about a minute to make sure oil was getting everywhere, it was, including on the floor from a rather significant leak on the oil pump housing. I will deal with that when the engine comes out, access will be much easier then.
I tried again but it still wasn't having it so I went back to my plan of looking at the valve gear while I turned the engine over slowly with a ratchet. It didn't take long to realise that the valve timing was 18 degrees out.
In yer average 4 stroke motor the cam turns at half the speed of the crank, this is done by having a sprocket on the crank that is half the size of the one on the cam a chain connects the two together. The cam and drive gear both have marks on them that have to be aligned for the valve timing to be correct - these are in the form of dots that denote top dead center. In a 4 stroke engine the piston reaches the very top of it's travel twice, the valves are opened by the cam, when the piston is at TDC and both inlet and outlet valves are closed that cylinder is at it's ignition stroke and soo the points should just be opening and the rotor arm should be pointing at the cylinder concerned - always cylinder number one when doing this job.
Mine wasn't. The rotor arm was pointing 180 degrees from where it should have been. I am not sure how that happened and was about to take my engine to pieces when I had a brain wave - if I took off all the ignition leads and connected them up in the correct order but started 180 degrees out then in theory it would work. I did that and then gave it another go.
i used some starting fluid and my outboard primer was pressed back in to action to make sure the carbs were full. I held the chokes open and preyed for the best. I do believe I heard it fire and I was pretty sure I could smell exhaust gas. I held the starter and then gave it a wee bit of throttle and she burst in to life. It did not run well, I wouldn't really expect it to, the tappets still were not full, the timing was only approximate and the carbs have not had fuel in them since I cleaned them 7 or 8 months ago. I let it run until the carbs drained down too far to work properly and allowed myself a congratulatory couple of minutes before I refilled the carbs and tried again. This time it ran a lot better but I could hear a screeching noise - given that I was running it just on headers ie with no exhaust it was clearly a very loud screech, I concluded it was coming from the starter motor that wasn't releasing when the engine fired. It seems to be better now, I took it off and lubed it lightly, still not convinced it's in the best of health though, I may try and source another one. I am only running it for a few seconds as it does not have the cooling system connected yet. Oil pressure looks good at 30 psi at idle, I'm not convinced I have a proper flow to the rockers though, I need to investigate that a bit further.
At least I now know the engine runs and I can't hear any nasty knocks coming from the bottom end, it doesn't seem to be burning any oil either. It's firing on all 8, my only problem seems to be a massive oil leak at the oil pump, I shall investigate that next. In the meanwhile aia think I shall celebrate with a large Scotch, today has been a good day.
Brief update - the cam timing was not out 180, it was just the distributor that was out 180. This thought came to me at 2 am one morning - I hate it when that happens. Anyway, she runs, that's the main thing.
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