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BMCMidgetLover

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A 1275 has been rebuilt, and now when the timing mark is at its spot on the timing marks, the number 4 cylinder is closed and #1 valves are rocking. When you put the distributor in it wants to fire #4. Referring to Robert Bently's fig A12 on page 62 the left is up and the right is down. Could the number #4 be used to time the motor or does the motor have to come a part?
 
Not sure I understand what you're asking, but since no one else has answered, I'll try.

Are you saying that, when the timing marks on the crank pulley line up with the pointer, cyl no. 4 seems to be at top dead center? If so, you need to turn the crank one more revolution and then no. 1 will be at TDC. Then you can install the distributor and time things in the usual manner.
 
I suspect you have not installed the distributor drive spindle with the correct procedure. Below is quoted from the Bentley shop manual.

"Turn the crankshaft until No . 1 piston is at T.D.C. on its compression stroke. When the valves on No. cylin.der are 'rocking' (i.e. exhaust just closing and Inlet Just opening) No. 1 piston is at the top of its compression stroke. If the engine is set so that the groove in the crankshaft pulley is in line with the largest pointer on the clutch cover, or the dimples in the crankshaft and camshaft gears are in line, the piston is exactly at T.D.C.
Screw the -5/16 in. by 3-1/4 in. UNF. bolt into the threaded end of the distributor drive gear and, holding the drive gear with the slot just below the horizontal and the large offset uppermost, enter the gear. As the gear engages with the camshaft the slot will turn in an anti-clockwise direction until it is approximately in the two o'clock position. "
 
I put a line on the head of the 5/16 bolt relative to the slot in the drive spindle to help gauge the starting and ending point of the rotation. Took me a few tries to get it positioned correctly.
drive spindle.PNG
Gary
 
As stated before you appear to be one turn out on the crank and the dizzy drive gear is also 180 out. Once you are at #1 firing (#4 valves at overlap) use a long, 4-5 inch, 5/15 NC bolt in the dizzy drive to position the drive correctly.
The longer the bolt the easier it is to fiddle the drive into hole in the block for the bottom to slide into as well as meshing with the cam gear.
Remember the drive slot and dog on the dizzy are offset just enough so that it will slip in easily. If there is any resistance installing the dizzy it is backwards.
 
I suspect you have not installed the distributor drive spindle with the correct procedure.
 
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