IH PARTS AMERICA

IH PARTS AMERICA (https://forums.ihpartsamerica.com/index.php)
-   Transfer Case Tech (https://forums.ihpartsamerica.com/forumdisplay.php?f=52)
-   -   Scout 80 Vibration on initial acceleration (https://forums.ihpartsamerica.com/showthread.php?t=12363)

Captainkerber 07-28-2015 11:56 AM

Scout 80 Vibration on initial acceleration
 
I have a 1962 Scout 80 with a 152
the rear end has been change out to a Dana 44 off a Scout 2
when I let off the clutch to accelerate it vibrates pretty bad.
Looking at the driveshaft you can see it bouncing back and forth when under load. Any ideas.

I don't remember if it started after I rebuilt the transfer case or when I upgraded to the Dana 44. Hopping for some suggestions before I start in on it again.

Scout-It-Out 07-28-2015 02:43 PM

Re: Scout 80 Vibration on initial acceleration
 
What I want to know is how you can see the drive shaft while you accelerate?:icon_wink: which way is the drive shaft moving? Are your u joints good? My first thought would be a clutch but the drive shaft shouldn't be doing anything but rotating.

FDChappie 07-28-2015 03:33 PM

Re: Scout 80 Vibration on initial acceleration
 
It could also be a bad motor mount.

Robert Kenney 07-28-2015 04:25 PM

Re: Scout 80 Vibration on initial acceleration
 
I guess I would ask if it shudders only while the clutch is slipping like when you take of from a start, and the shudder stops once your moving and you have your foot off the clutch pedal?

If so I would suspect the pressure plate.

If it shudders either way even while rolling, verify your u-joint phasing and angles.

ihpartsjeff 07-29-2015 06:03 AM

Re: Scout 80 Vibration on initial acceleration
 
What gear ratio does the Scout II rear axle that you installed have?

Captainkerber 07-30-2015 06:15 PM

Re: Scout 80 Vibration on initial acceleration
 
Ok so a little more information the
gear ratio is 3.54
it is different from the front I do to put it in 4 wheel unless in sand.
The motor mounts and tranmission mounts are new
if I let the clutch out very slowly the shuttering is minimual but that is going to burn the clutch out if I make that a standered practice. It is the worst when I star out up hill and is not noticeable at all when I am at speed even I f I accelerate. I do fell it if I slow down like to go over a speed bump with out putting in the clutch then try to accelerate. Low gear it is not as bad.
I did rebuild the transfer case and am did not have the correct measuring device to check the end play to decide the correct sizing for the shims. Would that cause this sort of shuttering.
And I could see the drive shaft by taking of the pannnel covering the transmission o the Scout 80.

FDChappie 07-30-2015 08:38 PM

Re: Scout 80 Vibration on initial acceleration
 
Has this been an on going issue or did it suddenly happen?

Scoutboy74 07-31-2015 08:41 AM

Re: Scout 80 Vibration on initial acceleration
 
Does this still have the Dana 18 twin stick case? Your stock rear axle would have been offset to be in better alignment with the d18 rear output. The sii axle is centered, which will be putting your rear shaft in a bit of a bind, but shouldn't be enough to cause this issue. It will wear your u-joints out a lot faster though.

Improper t-case output shaft end play can cause all sorts of issues. Some immediately evident and others not so much until later on. Another possibility is the drive shaft being out of phase. The best way to check the phase is to drop the shaft and set it on a level surface to compare the front and back yoke orientation. They should be in perfect alignment. Even being out of phase by one spline can be a problem. While the rear shaft is out, you can then engage the front axle in 4-hi and go for a test drive to see if the shudder condition is any different running on the front shaft only.

FDChappie 07-31-2015 08:45 AM

Re: Scout 80 Vibration on initial acceleration
 
Perhaps Jeff should institute an annual prize for the member that comes up with the most obscure answer to a problem. I assume the spline issue would be on the slip yoke?

Scoutboy74 07-31-2015 08:54 AM

Re: Scout 80 Vibration on initial acceleration
 
Quote:

Originally Posted by fdchappie (Post 81855)
perhaps Jeff should institute an annual prize for the member that comes up with the most obscure answer to a problem. I assume the spline issue would be on the slip yoke?

Correct. Most obscure answer.:crazy: that's a good one. Its a fairly well known issue both on this forum as well as others. Now if I could only find my crayons...:icon_rotate:

Captainkerber 07-31-2015 11:22 AM

Re: Scout 80 Vibration on initial acceleration
 
It has been an ongoing problem I will try to check the drive shaft tomorrow evening. Thanks for the help.

FDChappie 07-31-2015 06:44 PM

Re: Scout 80 Vibration on initial acceleration
 
Quote:

Originally Posted by scoutboy74 (Post 81859)
correct. Most obscure answer.:crazy: that's a good one. Its a fairly well known issue both on this forum as well as others. Now if I could only find my crayons...:icon_rotate:

True your answer is fairly common :winky:. Perhaps it would have been better stated best answer to an obscure question. An exclusive tee shirt that says IHPartsAmerica genious.:thumbsup:


All times are GMT -8. The time now is 08:06 AM.