B230 Engine Coolant drain torque

[Chooch84]

Hi,

I'm changing my engine block coolant drain to one used on the B230 engines with an oil cooler and not the water/oil heat exchanger. My current modified setup is more of a bodge and a risk and not a properly engineered solution.


Do you know how much torque should be used for this brass fitting? I understand it's an NPT type of thread so it can be tightened only so much. I could guesstimate, but there must be a rough value to work with?!?

Many thanks in advance!


T

[lynns hubby]

If it is NPT which it looks like, you will need to seal the thread with either a Loktight type thread sealant or PTFE tape as the thread is tapered. My preference would be tape if you are comfortable that you know how to use it. It has to go on in the direction that will wrap around the fitting as you tighten it otherwise it will come off as you tighten the fitting. Don't be tempted to put too much on, a couple of turns is sufficient. Get a reel from a plumbers merchant for penny's. Just remember its brass not steel so don't go heaving as tight as you can get or you will end up snapping it. As its a tapered thread you will feel it getting progressively tighter after a couple of turns. All you need is enough to be satisfied that it will not unscrew itself as you are not looking for any stretch or yield point as you would be with a bolt.
As a guide, I would screw it in as far as you can by hand and then get a couple of full turns with a spanner. If it leaks you can give it another "Nip".
I appreciate this all sounds easy and I am not trying to be patronising in any way but I do not know your capability's or confidence in these type of tasks.
Good luck.

[Bob Meadows]

A low strength adhesive is also useful for sealing threads/retaining fixings:~

Normal hand tools will undo them- avoid high strength if it needs to be removed.
(A taper thread is normally self sealing- no need to over tighten)
Bob.

[Forrest]

Not Volvo-specific, but some generic guidance here on NPT pipe threads. Note that the English torque values are in INCH-pounds, not to be confused with ft-lbs, and are hence all quite low.

https://www.engineersedge.com/hardwa...tion_13424.htm

[Chooch84]

As it looks like the thread already has a sealant applied, I'm probably going to give the PTFE tape a miss. If this doesn't work then I have some loctite 542 thread sealant which should work in this situation. Thank you for the responses, hopefully, if the weather holds out over the next week or two I'll get on with doing this job.