742 B timing marks

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Russell

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Dec 27, 2005
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I just replaced the head gasket on my machine after it rusted through and squirted coolant all over the exhaust manifold. Fortunately, there was no breach into the crankcase or combustion chambers. I believe I followed the instuctions in the repair manaual correctly in re-assembling, but it does not want to start. On page 7B-49 there is the discussion and sketches re: timing belt. I found the timing marks on the camshaft pulley and top cover easily. In picture B it shows how to line up the timing marks on the crankshaft sprocket. The sketch isn't exactly like my engine, so here's first question--the sketch shows a pretty fine pointer attached to the engine case, and a pencil -size timing mark on the sprocket. On my engine the pointer is more substantial--it's part of the casting, about 1/8" in diameter. Location is the same as in the picture. The only mark I could find on the crank sprocket was a tiny dimple like a punch mark--not very substantial, but all I could find. Are these correct? On page 7B-4 there is the description of how to time the engine. It describes a notch on the crankshaft pulley. I am accustomed to seeing these notches on many engines, but there certainly is not one on mine. All I have is the little punch-prick described above. Is this the timing mark I should see with my timing light?
 

OldMachinist

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You must be working from a different version of the 742 service manual than mine because the 7B section in my book is for the Ford motor. I've looked at the Mitsubishi section and it sounds like you got the timing belt marks right but the marks for ignition timing should be on the V belt pulley that goes on after the belt cover.
 
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Russell

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You must be working from a different version of the 742 service manual than mine because the 7B section in my book is for the Ford motor. I've looked at the Mitsubishi section and it sounds like you got the timing belt marks right but the marks for ignition timing should be on the V belt pulley that goes on after the belt cover.
Old machinist (from old forester)- mine is probably older or newer than the Ford version. After sending my message, I reexamined the setup and found that the presumed timing mark on the crank sprocket is a punch prick just above one of the threaded holes. The v-belt pulley has a punch prick near the outer perimeter, but perfectly in line with one of the four holes, so the assumption is that these are supposed to line up. I adjusted the distributor so my timing light flashes on the timing mark at TDC when using a remote starter. That setting ought to get it started, at which point I can adjust it properly, but the old girl still doesn't want to start.
 
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Russell

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Dec 27, 2005
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Old machinist (from old forester)- mine is probably older or newer than the Ford version. After sending my message, I reexamined the setup and found that the presumed timing mark on the crank sprocket is a punch prick just above one of the threaded holes. The v-belt pulley has a punch prick near the outer perimeter, but perfectly in line with one of the four holes, so the assumption is that these are supposed to line up. I adjusted the distributor so my timing light flashes on the timing mark at TDC when using a remote starter. That setting ought to get it started, at which point I can adjust it properly, but the old girl still doesn't want to start.
Continuing saga, things still don't line up. I was hoping to post pics of timing marks, but apparently we can't do that. With what clearly appears to be a timing mark on the crank sprocket aligned with what clearly appears to be a pointer, no 1 piston is nearly at the bottom of its stroke. By removing all the plugs and using a stiff wire to follow the piston movement, top of stroke appears to be about 120 degrees after the timing marks alignment. I did not remove the crank sprocket in my teardown, and it appears to be properly in place--key-way, etc. Engine is a Mitsubishi gas, Bobcat SN is 509420518 I suppose I could just turn the crankshaft until no 1 is at the top of the stroke, line up the cam sprocket timing marks and install the distributor with the rotor pointing to no 1, and fire away, but that is not what the book describes, and I am not much inclined to work that way. Any suggestions ?
 

OldMachinist

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Continuing saga, things still don't line up. I was hoping to post pics of timing marks, but apparently we can't do that. With what clearly appears to be a timing mark on the crank sprocket aligned with what clearly appears to be a pointer, no 1 piston is nearly at the bottom of its stroke. By removing all the plugs and using a stiff wire to follow the piston movement, top of stroke appears to be about 120 degrees after the timing marks alignment. I did not remove the crank sprocket in my teardown, and it appears to be properly in place--key-way, etc. Engine is a Mitsubishi gas, Bobcat SN is 509420518 I suppose I could just turn the crankshaft until no 1 is at the top of the stroke, line up the cam sprocket timing marks and install the distributor with the rotor pointing to no 1, and fire away, but that is not what the book describes, and I am not much inclined to work that way. Any suggestions ?
To post pictures they need to be hosted somewhere on the net like PhotoBucket. Then just copy and paste them into your post.
 
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Russell

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Dec 27, 2005
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To post pictures they need to be hosted somewhere on the net like PhotoBucket. Then just copy and paste them into your post.
Try this link. It should show 2 pics of timing marks, but it may also show 20+ pics of a recent logging operation http://s1198.photobucket.com/albums/aa454/VTtreegrower/
bobcat timing 1

IMGP0918.jpg
 

OldMachinist

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Try this link. It should show 2 pics of timing marks, but it may also show 20+ pics of a recent logging operation http://s1198.photobucket.com/albums/aa454/VTtreegrower/
Russell, take a look at the crankshaft pulley again and look for a notch down in the sprocket teeth. This is the mark you need to line up. The dimple I see in your picture is for lining up the v belt pulley.
 
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Russell

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Dec 27, 2005
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Russell, take a look at the crankshaft pulley again and look for a notch down in the sprocket teeth. This is the mark you need to line up. The dimple I see in your picture is for lining up the v belt pulley.
Sure enough, there is another mark. Thank you a hundred times !! Going by the book, there is not a hint that such mark even exists. Poured aliitle gas down the carburetor, and she fired right up. Made appropriate notes in the manual. Thanks again.
 
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