Torque Setting

[dirtrack49]

Hello,
Can anyone please give me the torque setting for a 230SL water pump to water pump housing (five bolts) and fan blade (3 bolts)?

About to finish replacing all the hoses and repairing the water pump housing and thermostat housing on my 66 230SL and I can't find a torque value anywhere.

Your help will be greatly appreciated.

Happy Thanksgiving.

 

[Benz Dr.]

I turn until they're tight. These are only 6mm hardware in an aluminium bore so the screws can beak off and or strip out threads easily. Normally, a steel screw in aluminium is torqued around 18 - 22 ft-lbs but that may be more than you need for this application. 

[stickandrudderman]

The torque setting is known in the trade as "NVT".

[dirtrack49]

Thanks for the responses. Thought there might be some value listed somewhere. It seems when I took the pump off from the housing, they were not on very tight. My problem is that I have a tendency to over tighten things a bit.
I think the fan bolts were on very tight, however, I am not sure what value I should torque them at. Or maybe just use some locktite on the fan bolts?

I am guessing that "NVT" might be not very tight???

It just seems to me that the water pump would need to be pretty tightly put on seeing all of the spacers and fan pulley hanging off of it. But since it has 5 small bolts holding it to the housing, maybe that's all it really takes?

[stickandrudderman]

NVT is indeed Not Vey Tight but it does take a lot of practice to get the right feel for this. Use a 3/8 drive ratchet and grip it around the drive end, not at the end of the handle. (You will then have about half of the handle's length protruding from your fist).  You should then be able to tighten it correctly without over-tightening because of the reduced leverage you've given yourself.

[Benz Dr.]

We've always called it '' mechanic's feel '' because that's what it is. The difference between stripping out a thread, breaking something off, or when it's just right. If you don't have it, you will after you have to un-$&#% enough things you did wrong.

[Shvegel]

My friend is watching over his friend while he changes a valve cover gasket on a 6cyl BMW.  He broke off 4 bolts tightening them so my friend fished them out and he has now broken off 5 more.

[Benz Dr.]

Re-read post number 5.

[dirtrack49]

Just wanted to reply to what "Stick" and "Benz Dr." passed along.

I got everything back together and used the technique that "Stick" had described. Works like a charm. In fact the water pump itself, is something that you could pretty much tell how tight it should be just by feel as 'Benz Dr." stated.

Thanks for the help and the technique.