McDonald Imperial Super-Diesel

Once again I thank all of the members who offer ideas and help.
Hi Jarrod, yes the white marks are back to where they were when I took it apart. There are the punch marks under the Nitto pen marks.
hayseed, if you look very carefully the crankshaft gear is exactly back in the same position. In the original pic the keyway is full of crap but it can be seen.
Mrsmack, yes everything is aligned the same as in the earlier picture, there is a lot of grease in the keyway in the earlier picture. It will unlikely that the timing has been messed around with because of the trouble in removing the flywheel/s at the beginning of the saga. I am fairly happy that it has not been messed with. As for knowing for certain, there is no workshop manuals only information from other McDonald owners who have been down this road before and fortunatley there are a few who continually offer information and a heap of help.
Bluey, so far I have not found any marks on either flywheel and the only way of checking TDC is by removing the top cover from the sump and look at the crank.

Something that I have discovered is that when I stripped this engine it had to be in the correct timing position because of the trouble I had removing the flywheel. The other thing is that when I stripped it there was no head, valves pushrod in place not even a piston fitted so when I turned the engine over so the crankshaft was at close enough to TDC I made a mark on the cam gear and although there was already one mark there it was punched below a tooth the same as the crankshaft gear is when normally it would be at the bottom of a tooth to show you where to put the crankshaft gear, so I made a second punch mark so it was clear where it was to go. This tends to lean me toward the timing being correct.

Hi, I have just checked the timing on my SD engine which I think would be the same timing as you're SE,with the timing marks lined up on the gears the crankshaft big end journal is at the 6 o'clock position and the cam lobe is at maximum lift ie exhaust valve fully open. This engine runs and starts easily.
Regards John

When the marks I have are aligned the crank is at TDC on intake stroke, (9 o'clock) so sounds a bit different. Bare in mind my 9 o'clock is based on it being horizontal and TDC is 9 and BDC is 6 o'clock.
When I get back to it over the weekend I will take more notice of the valve timing because there are 2 lobes on this cam, one higher than the other.

I think we have a translation problem. To my mind TDC is when the piston is at the top of the stroke irrespective of the engine standing upright, horizontal or upside down.

Too much laying down cobba, stand up!

Personally I'm not going to even hazard a guess as I don't know what the two smaller (upper and lower) gears are for even!? :blush:

Good luck, ignore my dribblings, and plug on with it regardless . . .

I am a bit behind in the descriptions of TDC BDC but to my mind there will be two positions for the mark as the camshaft turns at half the rate of the crankshaft> Depending on compression or exhaust stroke TDC, one matching and one not matching.

I am struggling to see how you could stuff up the valve timing if the marks match as all the gears are locked in place with keyways, flats or master splines in gear timing. Chains and belts yes, a link or two out more possible without care.

Easy for us to say from 1,000km away! Keep at it.

Lang

Hi, standing on the cranking side of the engine facing the flywheel it runs in a clockwise direction so TDC is 9 o'clock and BDC is 3 o'clock. There are 24 teeth on the crankshaft gear so each tooth equals 15 degrees of crankshaft rotation so on closer inspection of my engine when the timing marks are lined up the crankshaft is at the 5 o'clock position ,not 6 o'clock on the exhaust stroke with the piston moving toward TDC. As cobba has said the timing between my engine and his could be different but the relationship between the crankshaft and cam lobe stays basically the same IE exhaust valve open on exhaust stroke and inlet valve open on inlet stroke and both closed on compression stroke. My engine is the earlier open crank version of Cobba's so much easier to see all the moving parts in relationship to each other. this could be all wrong just ask my wife. Regards John

Still playing with it and also putting on some accessories as well.
The gear below the crankshaft is for the oil pump only and does not need timing. The crank gear is connected to the cam gear and then that also drives the governor at the top. S that covers all 4 gears.
It is only the cam and crank gears I need to get right and the more I play with it as is the more I feel it is right. Will go back out and play some more to see if I can talk myself out of it.
P.S. I am still having fun !

cobbadog wrote: P.S. I am still having fun !

^^^^ That's all that Matters.. Carry on..

Decided that it is what it is and started putting the extras on like the water hopper after welding a crack, the air cleaner and the home made fuel tank. Will continue tomorrow and fit the speedi-sleeve on the crank shaft, again, the side cover and flywheel and then blue the new gibb key in place fill the sump with some oil and fuel it up for a start, I hope.