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Topic: Torque value for radiator bolts (Read 2630 times) previous topic - next topic

Torque value for radiator bolts

Is there a specific torque value for the bolts on the side of the radiator?
I have not found one and all I've read is not too tight.
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: Torque value for radiator bolts

Reply #1 –
Check the bolts to see of they are grade 2 or 5 then google torque chart it will tell you what the torque needs to be on different sizes and grades.  grade 5 will have 3 marks on the head grade 2 I don't think has any marks on head.
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Torque value for radiator bolts

Reply #2 –
I have read on the forum that there are some bolts which need to be checked for torque if the radiator has a small leak.  Are these the bolts being referenced?

Thanks.

-FT
2001 U270- 34'
with Aqua-hot
Travel Safely
Have Fun!!

Re: Torque value for radiator bolts

Reply #3 –
Quote from: FtRoadTrip –
I have read on the forum that there are some bolts which need to be checked for torque if the radiator has a small leak.  Are these the bolts being referenced?

Yes if the leak is between the core and the end tank.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Torque value for radiator bolts

Reply #4 –
Thanks Mike. 

I have a drip.  Very minor.  Just having to add a little fluid here and there. 

I am hoping that I do not have to change out the radiator any time too soon.  Seems they all have to be changed eventually.

I appreciate your help.

-FT
2001 U270- 34'
with Aqua-hot
Travel Safely
Have Fun!!

Re: Torque value for radiator bolts

Reply #5 –
I don't know for sure but I would not follow a standard bolt torque chart.
The radiator manufacture would be the best source.  Might that be Atlas?

That said, I did find this from Rocore who makes small to large radiators in addition to heat exchangers.
See second to last page: http://www.rocore.com/phocadownload/standard-radiator-iom-manual.pdf
For re-torqueing:
Remove the fan or core guards in the area of the leak. Start re-torqueing these bolts from
the center of each side of each header and continue moving outward. All header bolts
should be re-torqued at this time. The torque for these bolts should be 13 to 15 ft-lbs.
Then replace the guards. CAUTION! Do not over-torque. Over-torqueing may damage
the gasket.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Torque value for radiator bolts

Reply #6 –
15 sounds high IMHO. The bolts are small and the rubber gasket is thick.    Just enough with 2 fingers ona 1/4in drive.
 It's a lot easier to snug them than replace the gasket

Re: Torque value for radiator bolts

Reply #7 –
Ft those are the ones.
I have dripping from the lowest bolt at the rear .
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: Torque value for radiator bolts

Reply #8 –
Sorry, I thought you were referencing the bolts that hold it in place,  Personally I would use a 1/4" drive inch pound torque wrench
13lb = 156 inlb,15lb=180inlb and I would stay on the low end if that stopped the leak.  Also, if you only torque some of them you may distort the gasket and cause it to leak worse than it was
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Torque value for radiator bolts

Reply #9 –
Quote from: Lt403 –
Ft those are the ones.
I have dripping from the lowest bolt at the rear .

That is the same spot I am looking at. 

I think I will give Atlas a call next week.  It would be great to get their torque spec. 

Thank you Frank.
2001 U270- 34'
with Aqua-hot
Travel Safely
Have Fun!!
 

Re: Torque value for radiator bolts

Reply #10 –
Think in the case with the thick rubber gasket you can throw out any torque spec,if Atlases spec does not stop the leak,then what,unless the nut and bolt somehow got loose it was torqued to that spec to begin with.Would try and find a local shop that can rebuild your radiator and plan for that,try some Bars leak first.
96 U270 BUILD 4810
85 380SL
Drummonds TN.