Oil pump gear & crankshaft spline alignment

Evan

Full member
Location
Texas
The spline has a dot & the oil pump gear has a dot. They line up. Ok the arrow to line the oil pump gear on crank to oil pump drive gear is about 6 teeth left of dot. This aligns w/ the oil pump drive gear arrow. Thought the arrow was supposed to be about 120 degress right of the dot on oil pump gear. Ballpoint pen shows position of arrow on manual. Has to be as is. Right? Don't remember this one. Then when aligning w/ timing chain gear to head marks on top all falls into place. & then the threads of the crank nut are recessed on one side. Recessed threads goes to the inside. & then should I put the primary chain in the oven before fitting on the crank & clutch? Last time I did it was in the summer. It was hot. Wrestled w/ it for an hr. Sweating all over. (& then the oil pump drive gear peg fell out of shaft but it fits back in OK)
 

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As you say, the dot on the crankshaft and the dot on the small drive gear line up. At top dead centre these will face vertically up and the etched arrow on the drive gear will face towards the oil pump. With the shaft fitted to the oil pump, have the etched arrow on the oil pump gear aligned with the etched arrow on the crankshaft gear. In this position the small keyway on the shaft (that locates the ignition/advance rotor will be facing vertically up, as will the dot on the big gear). It is easiest to fit the shaft and big gear into the oil pump first, then rotate it so that the etched arrow faces the crank, then fit the crankshaft gear.
Yes the nut has the recess in towards the splines.
You should not have to heat the primary chain/s to fit it, it just goes onto the crankshaft sprocket and the clutch drum as you are fitting these before getting into the ignition timing.
 
The spline has a dot & the oil pump gear has a dot. They line up. Ok the arrow to line the oil pump gear on crank to oil pump drive gear is about 6 teeth left of dot. This aligns w/ the oil pump drive gear arrow. Thought the arrow was supposed to be about 120 degress right of the dot on oil pump gear. Ballpoint pen shows position of arrow on manual. Has to be as is. Right? Don't remember this one. Then when aligning w/ timing chain gear to head marks on top all falls into place. & then the threads of the crank nut are recessed on one side. Recessed threads goes to the inside. & then should I put the primary chain in the oven before fitting on the crank & clutch? Last time I did it was in the summer. It was hot. Wrestled w/ it for an hr. Sweating all over. (& then the oil pump drive gear peg fell out of shaft but it fits back in OK)
Put engine at TDC without either oil pump or crank gear. Put in pump gear and turn it so that it's keyway is at 12 o'clock. Engine is now timed, so just slip on the crank gear.

Paul
 
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Ok thanks. Engine 8787 has no mark on the oil pump crank gear. But Not doing it now. But thanks anyway I'll definantly get back on that one.
 
Ok thanks. Engine 8787 has no mark on the oil pump crank gear. But Not doing it now. But thanks anyway I'll definantly get back on that one.
Might be replacement parts that were never marked after installation. AfaIk, all engines had timing marks ex-factory.

A common mistake made here is the improper matching of the oil pump and crank gears. The crank gear carries a number on the rear side indicating calibration range. This can be anything between -10 to 20. When the gears mesh, they MUST have around 0.1 mm, just noticable, play between the teeth. No play will result in a horrific whine, too much causes a little additional rattling and slightly erratic ignition timing. Clearance can be adjusted with a gear of different calibration.

piet
 
Might be replacement parts that were never marked after installation. AfaIk, all engines had timing marks ex-factory.

A common mistake made here is the improper matching of the oil pump and crank gears. The crank gear carries a number on the rear side indicating calibration range. This can be anything between -10 to 20. When the gears mesh, they MUST have around 0.1 mm, just noticable, play between the teeth. No play will result in a horrific whine, too much causes a little additional rattling and slightly erratic ignition timing. Clearance can be adjusted with a gear of different calibration.

piet
Not to mention, the early ones having coarser, wider, teeth.

Paul
 
Ok thanks. Engine 8787 has no mark on the oil pump crank gear.
With the marks aligned the pistons are at tdc and the arrow on the oil pump gear points directly at the centre of the crankshaft. You can see this even without marks on the crank and its gear.
 
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