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Old 05-09-2018, 08:47 PM   #349
LockDoc
The Older Generation

 
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Join Date: Aug 2006
Location: Montezuma, Iowa
Posts: 25,271
Re: Working Man's Burbon

Quote:
Originally Posted by HO455 View Post
I have about 200 miles on the new engine and all is well with it (No leaks yet!). It has much better off idle torque than the old 305. One thing that has become apparent is there is a much more pronounced vibration at highway speeds than before. When we were dropping the new engine in I discovered that one of the motor mounts had been cross threaded when it was last installed. (I couldn't have checked it before hand, that would've been smart so I did it the hard way, with lots of cursing to make it easier.). So my thinking is the new motor mounts made the engine sit higher in front and may have put the drive shaft angles out of spec.
First thing was to put the rear end on jack stands and set the rear ride height. (I had cut down a 2x4 when I when to the alignment shop to check all four corners for height before they aligned it.). Using this board to set the height I squirmed under the truck with my trusty angle finder. The first angle to check is the transmission. I prefer to measure the angle off of the end of the u-joint cap. But the one at the transmission is the spring clip style which I would rather not have to remove. Fortunately the transmission yolk is machined pretty well and I am fairly happy with it being true to the output shaft centerline. (You can verify the surface by reading the angle finder on the bottom and then rotate the shaft and get the reading with it on the top. They should be the same if the surface is true.). Measure the angle of the first drive shaft, the second shaft and then the pinon angle of the rear end. The photos show the finder hanging by the magnet. I didn't use the magnet when taking the readings . I use the V-block side as it is a more positive way of locating the finder. I was able to mimic the readings with the magnet side to take the pictures. I was not happy with the yolk surfaces on the rear end so I used a socket to take a reading off of the u-joint cap.
The readings ended up being 3.5* down on the transmission
0* on the front drive shaft
2* down (down at the rear) on the rear drive shaft
2* up on the pinon.
It looks like I have some work to do. The front u-joint should be in the 1 to 1.5 degree range not 3.5 degrees. I will go out in the morning and raise the rear of the transmission. I think that if I can get the tranny to 2* then the forward drive shaft will move to about the same and then most likely I will have to shim the pinon to finish the alignment. More to come.

It seems like there is always something to throw a monkey wrench in the works..... Hope you get it sorted out.

LockDoc
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