strange issue...any thoughts?

old ford fan

old ford fan

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i went out to the back field and dragged the old doodlebug down to the shop to check out the engine for possible use in my dads 31 coupe (long story). This appears to be an early 29 block that was reworked at some point in its life as the cylinders are .030" over. I dropped the pan and it looks quite clean and it still turns over. I poured some transmission fluid on the Pistons and valve stems and turned it several times. Bearings seam to be free of excessive play so I want to fire it up and see if it runs. I spent time going over most items and I began adding parts such as manifolds, carb, starter, water pump, etc. I went to turn the crank so I could insert pin on cam to time the engine. The piston is consistently about 1/2 to 5/8" past TDC when the pin drops into the dimple. I don't feel like this is right. Shouldn't I be AT TDC? I don't know the history of this thing other than we bought it from a guy down the road who had an entire junkyard full of A and T parts. I have a strong idea what has to happen next but I would greatly appreciate your thoughts/suggestions.
 
FWIW, the timing cover from a B engine is in a different place from that on an A engine. Higher, I believe. Maybe you have a B cover.
 
I believe it is a 1929 model A block and the timing cover has a round dimple in front, not oblong. No fuel pum block off plate. 1 piece flywheel housing.
 
I would remove the front timing gear cover and make sure the timing marks line up. The cam gear mark should line up to the right side of the keyway as you face it.
 
My theory.. Cam shaft / crankshaft timing is off. I can't help but think that whoever serviced the engine when it was bored over perhaps replaced the cam gear. (The gear looks to be in very good condition). Possibly missed the crank timing mark by 1 tooth? Could they have made this mistake and parked the thing cuz it wouldn't start/run? Or, is it possible that they advanced their timing to the max and ran slightly retarded without ever figuring out something was wrong? Do I need to pick the engine so I can remove the front cover to prove my theory?
 
Yes, you will need to put a board on your floor jack and lift the front of the motor just enough to remove the front yoke mount from the front cover. Then you can remove the timing cover and check the alignment marks.
 
Thanks guys, I'm anxious to get back to it (hopefully this evening). What puzzles me is that they were seemingly using this as a tractor at some point in time and it must have been running retarded, correct? Or is this still close enough that they could advance the spark (all the way) and still run ok?
 
Good point Russ. I checked to make sure valves are all moving freely and seem to seat without any binding so I'm thinking the valve timing wasn't off far enough to bend/damage any valves.
 
I think the picture is here...I think I can make out a very slight circle on the first tooth to the right of the crank key. Looks like I've got a slight issue with the pulley sleeve
 

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Yes, you do have to buy a new pulley, and the timing is 3 teeth off.

Are you sure it used to run like this?

Any chance the cam gear is not marked correctly?
 
Looks like it is 3 teeth off.
 

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Yes it was off 3 teeth. I have repositioned it and it is now lined up properly. The timing pin drops in and #1 is at TDC on compression. I am going to prep it so that I can run it on a stand and then I will tear down far enough to make any repairs and install new gaskets and seals. Also, did you see the cam gear? It is a deep red (almost maroon) color and it is spoked rather than solid. Was this the stock configuration or do you think it is aftermarket? Being that it was 3 teeth off, I can only wonder what the circumstances were after that gear was installed... Perhaps they couldn't even start it and gave up on it? The old timer I got it from moved back to Tennessee shortly after I bought it. The old guy lived on that property in a delpidated mobile home with no heat and no running water or sewer for many years. He sure knew a lot about model T's and A's!
 
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