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Shaft alignment

pete31

pete31

Regular Contributor
"can anyone tell me the correc

"can anyone tell me the correct,definative way to align my prop shafts, I've asked several people & received as many different responses, from using fishing scales to weigh the shaft & coupler to using a dial indicator. The boat is a 71 gless hull Trojan express with velvet drive transmissions & 225 hp 318 Chryslers. thanks in advance."
 
"Here's how I do mine:

"Here's how I do mine:

1. Loosen up all the coupling bolts and spread the halves a tiny bit--about 0.020 inches.

2.Mark the four sectors of the flange with marker (top, bottom, east west).

3. Feeler gage the gap at the top. Record. Then record the bottom gap.

4. Roll the coupling over 180 degrees and check again. The gaps should be the same as they were before (ie: the top gap now on the bottom, and vica-versa) or the coupling is running out on the shaft and needs to be fixed FIRST. (Ignoring this only makes things worse.)

5. Assuming the gaps "followed" the coupling around as you rotated it, then the coupling is not running out. Good! Move the front of the motor up or down to get the top and bottom gaps withon 0.003 inches of each other.

6. Next, it's time to do the side-to-side. You have established by now that the flange is not running out on the shaft(or corrected it) so the sides gaps needs to be equal as well. Move the front of the motor ot one side to correct any misalignment, again shooting for 0.003 inches max.

Jeff

PS: The boat needs to have been sitting in the water for a week or the readings may be off some."
 
"Thanks Jeff, I'm putting

"Thanks Jeff, I'm putting the shafts back in in a few weeks along with new cutlass bearings, I'll try the way you desrcribed with the boat still in the air, then re-do after its been back in the water a couple of weeks

Pete"
 
"Lost me on part of this expla

"Lost me on part of this explaination Jeff. In step #4, what do you mean by running out?"
 
"I have successfully aligned m

"I have successfully aligned my 440 (circa 1976) up and down using the vertical motor mount adjustments, but how do I adjust the front of the engine left and right horizontally? There are 1/2" or so horizontal rods going into the mounts with a bolt and nut. Do I loosen all these and shift the engine over manually, or is there a way to "fine tune" with a threaded adjustment? (sorry if this is a repeat...not sure if the last post worked)"
 
"Bolts:

"Run out means

"Bolts:

"Run out means the gap changes as you rotate the parts. You want less than .003 inches of run out.


Wayne:

Moving the mounts sideways is a PAIN! I use a small jack under the damper pulley to take the weight of the mounts, then bar them to one side with a crowbar. (A better way is to use a Porta-Power deal.) Also, on mine, I had to remove, clean and lube the mounts befoe the little ~*%^@( would move.

Sometimes it's better to pay the marina guys!

Jeff"
 
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