PeachParts Mercedes-Benz Forum

PeachParts Mercedes-Benz Forum (http://www.peachparts.com/shopforum/)
-   Diesel Discussion (http://www.peachparts.com/shopforum/diesel-discussion/)
-   -   Torque Settings? (http://www.peachparts.com/shopforum/diesel-discussion/64351-torque-settings.html)

Old Deis 05-08-2003 12:49 PM

Torque Settings?
 
I must have missed a day of school or have been asleep that hour somehow, but whenever I read the manuels they give two torque specs. Sometimes the two vary widely.
So which is the correct one to use? The lower or the higher? Or somewhere in the middle?

rwthomas1 05-08-2003 02:41 PM

I believe most fasteners are supposed to be torqued dry unless specifically stated. When there is a range I take this into consideration. A dry fastener gets the max torque value while if a fastener is greasy and cannot be properly cleaned I use the minimum value. Not sure this is the correct way but I haven't had any trouble with it. RT

DR.DIESEL 05-08-2003 04:32 PM

One is probably Newton Meters, the other FT lbs.
Use a conversion chart to see if the equal each other
when switched from NM to FTLBS.
DR.D

leathermang 05-08-2003 04:37 PM

All the automotive fasteners which you will be dealing with are designed to be torqued clean and...

LIGHTLY OILED... I promise you this is true....

This is industry standard for bolts....

rwthomas1 05-08-2003 06:15 PM

Hey Leathermang,
How about lug nuts/bolts? I put a little neversieze on 'em. People have told me I am crazy but I have never had a problem in 15yrs. Always torque them to spec. Nothing worse than the local tire chimps with impact guns..... I put neversieze on everything as I am sick of breaking bolts. Upon reflection I think you are right, lightly oiled is the way to go. Some people have differing ideas of "lightly" though. RT

leathermang 05-08-2003 06:32 PM

RT, Since my escapade riding my Harley to Estes Park Colorado in 1974... chunkin those nuts and bolts( repeatedly) that held the rear fender on I have used RED LOCTITE on everything I can find... I did not know it existed until a guy at a parts store told me about it.. ( I was about 24...)
I consider any fluid "oil' for torqueing purposes.... I just know that the friction dry is high enough it can adversly affect your gasket holding..
Anything that does not deserve Loctite deserves Neversieze...Amen....

Old Deis 05-08-2003 06:38 PM

I don't have a MB manual with me daytime. But I found a Chiltons Toyota. Reads much the same as the MB, except for the two tables showing both ft/lbs and NM.
The torque specs page reads:
(All reading in ft. lbs.)
Engine Type Head bolts Rod bearing bolts
22R 53-63 69-83

and so on...
I am still wondering which is to be used, and why?

leathermang 05-08-2003 06:42 PM

Can you post the rest of the table ? either scan or photo it ? There is something missing.. look on the edges of the table or the foot notes... that is not how they are usually given...

DR.DIESEL 05-08-2003 06:46 PM

Sounds like they just want you to stay in those ranges.
GM is the same in their manuals. Just shoot for somewhere
in the middle with clean lightly oiled threads.
DR.D

leathermang 05-08-2003 06:50 PM

I think he is questioning why they seem to list two different ranges... for one bolt...

Old Deis 05-08-2003 07:32 PM

So that's the answer? They are just giving a range, and we are supposed to stay in the middle somewhere?
I tried to type out a portion of the tables there, but the software here sort of fouls it up. I am sure everyone here has seen the torgue spec tables.
On some of these the range can be significant and I leave wondering if the bolts were tighened ok. The tendency is then to engage in overtightening. Not good at all to do that.

leathermang 05-08-2003 08:10 PM

If you are correct in reading both those ranges as ft lbs and listed for one bolt... then something strange is happening...so keep looking... I have never seen anything like that combo.... it does not make sense....without some intervening variable.. for instance , if they were listing for both oiled and dry... but it should say that somewhere in a case like that....hang in there , someone will come up with something...

dabenz 05-08-2003 09:39 PM

Yep, it's a range. The whole idea is to provide a specific tension on the bolt. Ft-lb on the end translates into lb of tension in the "shaft" with a lot of geometry. Now throw in the variables: new vs. used (corroded) bolt, lube vs. no lube on thread, smoothness of clamping surface (friction), replace with original or somebodies "equivalent." The engineer either goes insane trying to predict it all or CYAs himself and gives a range for the variable extremes. Sounds stupid until you think of the kind of life a bolt can live - seaside or desert, hot or cold, maintained or left to corrode away, lots or just a few lawyers.

Clean and lube or lock(tite), then tighten to your best judgement.

leathermang 05-08-2003 11:04 PM

"gives a range " ---- I can understand that.. but why two ranges with no written information as to what is covered by each ?
I still say something is missing from the 'table'....

Lycoming-8 05-08-2003 11:31 PM

The Toyota example that Old Deis input earlier was for a Toyota with a specific engine (22R) and then gave the head bolt torque range and finally the the rod bearing torque range. This was not two ranges for the same bolt type.


All times are GMT -4. The time now is 03:12 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website