Where are the timing marks on a David Brown 850 (Oliver 500)?

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Where are the timing marks on a David Brown 850 (Oliver 500)?

Kevin	Hello, I'm trying to get my Uncle's Oliver 500 running again. It's getting fuel and spark, but I need to verify the ignition timing. The problem is, I can't find the timing marks. The shop manual says they're on the flywheel behind a small cover. I can't find this cover anywhere. I looked in the clutch / pressure plate inspection cover behind the dash under the gas tank, but nothing there. There is a pin that sticks out on the left side of the block with two small holes below it. There is also "TDC" cast into the block. If anyone could shed some light on this, I would greatly appreciate it, Thanks.
AJ	In a word I can't tell you where the flywheel mark is if you can't find it on the left side of the bellhousing,the bell housing may be different than that used on the DB tractor,the pin you mention does it unscrew and go back in the hole the other way to engage with a hole in the flywheel?,the other way to do it is take out the four spark plugs,turn the engine by hand in the normal direction with your thumb blocking the plug hole of no1 cylinder,when you fee the compression on your thumb put a clean rod down the hole,turn the engine slowly till the rod stops rising,play about and find the highest point that will be TDC,mark the pulley to the front cover,now see where no1 plug lead fits into the distributor cap,put a mark on the distributor body in line with where the lead goes,remove the cap,the rotor arm should be pointing at the mark you made,turn the engine back a bit,connect a test lamp to the wire going from the coil to the points and the other end to ground,switch on the ignition,turn the engine till the pulley mark lines up with the cover mark,the test lamp should have just come on,if not loosen the distributor clamp and move the body against the way the rotor turns to bring the light just on,if the light is on move the body the other way till it goes off and back again till it just comes on,lock the clamp,take the test lamp off and put the cap and plugs back try to start,if it runs you may have to move the distributor to fine tune it,someone over at the dbtc.co.uk will know about the timing marks. AJ
Kevin	The pin does look like it will unscrew and go in either of the two holes. I'm assuming if it does and fits into a corresponding flywheel hole (or both) that would be TDC or 8* BTDC as the shop manual calls for? Thanks for the link to dbtc.co.uk. I'll check with them also. I'm bringing the tractor up to my garage within the next week and will try your method. It will be much easier in the future when the pulley is marked. Thank you.
Rodney	I am speaking simply from standpoint that we have a 780 selectamatic gas tractor and there is an inspection plate for the clutch plate on the right side of the tractor on the bell housing. Just forward of that is two holes. one is marked TDC. crank the engine over by hand. place a straight shaft that will slip into the hole and push it in until it is touching the flywheel. as you turn the engine by hand, when it is on top dead center.. you will feel the pin slip into an indention on the flywheel. It is then on TDC. remove the distributor cap and see if the rotor is aligned with the Numbetr one cylinder wire position. I'm assuming that it is a gas model
Kevin	I think it's somewhat similar to your's, however the clutch inspection cover on this tractor is on the upper rear portion of the bell housing under the gas tank. The two little holes are on the left on this tractor. So if one hole is TDC, I guess the other is where I set the timing, or the point where the points should just start to open? I was finally able to get the tractor up to my house this week and hope to have time to work on it later next week. Thanks.

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