Torque specs. for block heater installation?

leeds · Nov 19, 2011

I'm doing a block heater installation on a B3030 (engine: V1505D, block heater part number 70000-73274).

While there is no question that this is the correct heater kit for the V1505D engine, the instructions that come with the kit are for different engines and provide no torque specifications.

The installation is simple on the V1505D, it's a threaded unit that replaces the 17mm hex head plug on the left side of the engine block . . . I just want to make sure that I don't over-torque it. Does anyone have a good fix on the torque setting?

Danner · Nov 19, 2011

This link should get you into the correct ballpark:

Torque Guide

leeds · Nov 19, 2011

Hi Danner . . . much appreciate the quick reply.

I suspect that the torques for the link you supplied are too high in this application. Using the metric bolt table and assuming the lowest grade at the lowest end of the range, one might think that 60 ft-lbs would be good. However, scanning the net for automotive examples suggests something on the order of 32 ft-lbs and there are some block heater installation instructions floating around for other applications coming in at 40 in-lbs!

I can do the trial and error method starting from a quarter turn past finger tight, determining the torque, and then iterating from there. But between heating/cooling cycles to check for leaks, re-installs as needed at a slightly higher torque, until I zero in on the minimum torque that results in no leaks, a 20 minute job is going to turn into a multi-day affair

leeds · Nov 20, 2011

Just to close out the thread, 32 foot-lbs of torque with a two layer wrap of pfte tape works without any leaks or issues.

varmint · Nov 20, 2011

This might be a good place to recommend a thread sealant that a HVAC guy told me about when I was having serious troubles with leaking synthetic solar heating oil- regular pipe dope wasn't working, and tightening the fittings wasn't working. Called Leaklock, it is amazing stuff. Seems to be imprevious to about fluid you can think of, and it stops leaks. If your block heater is like mine, it's a tapered pipe tread, and the sealant is an important part of the installation.