Trouble replacing u-joints on volvo DP-A

[island567]

I have got the u-joints and yoke back in the double bearing box. I did not take bearings out. Just replaced seal, o-ring and bolt. The problem is when I torque the bolt to get the pre-stess readings, I tighten bolt as much as possible (with breakover bar) and I only get about 20 in-lbs of torque... is this enough or what is stopping me from getting more?

 

[muc]

Re: Trouble replacing u-joints on volvo DP-A

Did you install a new pretension sleeve?
How about a new bolt?
Why are you tightening to 20 in. lbs. of rolling torque?
I think with used bearings the spec is the low side of 9-14 in. lbs.
Might want to take another look at the Volvo Penta manual.

 

[island567]

Re: Trouble replacing u-joints on volvo DP-A

I did not replace the pretension sleeve. I did replace the bolt. The manual that I have says the rolling torque with used bearings is 7.5 N, which I thought meant "Newtons". the equate to about 66 in. lbs... if I am reading chart right. That much resistance doen't add up to me. that is why I am here.

 

[Don S]

Re: Trouble replacing u-joints on volvo DP-A

You MUST replace the sleeve, they are not reusable.

You are also confusing 7,5 N (Newtons) which is 1.6 (lbs) which is a weight measurement, not torque which is Newton meters that converts to inch or foot lbs.
The rolling torque in the manual is done with a weight scale, not a torque wrench.
In the later D and E models, Volvo changed from Newtons to Grams on this measurement.

Basically, you can't convert weight measurements to rolling torque.

Now, having said that, in the newer drives (SX/DPS) Volvo did use torque specs for setting rolling torque.
That spec is 9-14 in. lb. (1,0-1,6 N•m).
It's the same setup with the pretension sleeve and basically the same sizes of bearings.

 

[island567]

Re: Trouble replacing u-joints on volvo DP-A

Wow...I knew something was wrong. I total missed the weight reading and went right to torque readings. So its safe to say when I redo this, that the rolling torque reading I am looking for is 9 - 14 in-lbs. on a 1989 volvo DP-A. Thanks for the help.

 

[billbayliner]

Re: Trouble replacing u-joints on volvo DP-A

Here is a link to a video I made for a guy that filled his bellow and upper with water.

I want to further ad that being a critical procedure, the spring scale should be checked to make sure it is accurate. Fortunately I have all the equipment at my disposal to check and calibrate any tooling and found that my scale was off even when new.

Make sure to take your time so not to get to a point where you have to pull it apart and get a new pretension sleeve. Take your time and when you are close to losing the slop in the bearings tighten in tiny increments and recheck with scale. It is so easy to want to rush this.

I am not the best when shooting video and did not make this to win awards. I was under the pressure of the camera and even lost some words. :facepalm:


http://www.4shared.com/video/RY7K2oMz/Setting_rolling_torque.html

http://www.4shared.com/video/zpcYnHz_/Showing_rolling_torque_set_up.html Did this one alone. Needed 3 hands

 

[Don S]

Re: Trouble replacing u-joints on volvo DP-A

Just so you know where all this info came from,

SP/DP-A-C Manual #7731624
Pre-stressing new bearings: 10–15 N (2,20–3,30 lbs).
Prestressing used bearings: 7,5–10 N (1,6–2,2 lbs).

SP/DP-D & E Manuals 7797368 and 7797525
Preload new bearings to at least 500 grams minimum and 1000 grams maximum.
Preload used bearings to 500 grams minimum and 800 grams maximum.

SX/DPS
9-14 in. lb. (1,0-1,6 N•m) Manual 7743008
This is for used or new bearings nothing noting any difference in the service manuals.

The bearings are the same ones in all of the above drives, (3850852-3850853) and the double bearing box is aluminum in all versions.

The rolling torque is set using weight measurements in the first 2, the last it is done by a torque wrench using rolling torque.
The older style drives had different settings for used and new bearings, not so the SX/DPS version.

If this was my DP-A drive, By comparing the D&E weight measurements, I would use the SX method and keep the rolling torque in the 9 to 10 range and think nothing of it, but now you know how I would choose my numbers.

 

[billbayliner]

Re: Trouble replacing u-joints on volvo DP-A

9-14 in. lb. (1,0-1,6 N•m).[/B]
It's the same setup with the pretension sleeve and basically the same sizes of bearings.QUOTE]

Had my upper from my C1 apart last night and your post above made me realize what I forgot to do. I checked the rolling torgue on the bearing box and it was perfect. I wanted to grab the machine repairs newton torgue wrench and check the resistance with it and document it in my computer as I believe it can be a more precise setting with the said tool.

 

[Don S]

Re: Trouble replacing u-joints on volvo DP-A

My How Times Change

I sure wish I had the good sense back in the early and mid 90's when I was going to all those Volvo engine and drive tech schools, to ask if they ever tried to converted from weight to torque and how it checked out. That would have been an interesting topic.
But that was way before I owned a computer. Didn't have a clue what a forum was, iboats didn't exist and I didn't think I would be ever be explaining how these things get fixed over the internet. It's really kind of amazing.

 

[island567]

Re: Trouble replacing u-joints on volvo DP-A

I've got the double bearing box back together. Installed a new crush sleave, bolt and torqued down rolling assemlby till I achieved a rolling torque reading of 10 in. lbs. The bearings feel alot better with the proper reading. Thanks for the help.
Dave B.