Hello,

Exisiting pipes are 3 inch (~7.6cm) threaded pipes and were used for home heating oil. The biodiesel running through the pipes now are making them leak. My impression is that this is because biodiesel is thinner than heating oil.

So, is it improper to use threaded piping for biodiesel? Is the problem really because biodiesel is thinner?

Thanks!

What type of pipes? Copper, gal, polly, Aluminum?
How were the joints sealed? Tefflon tape, glue, rubber washer, nylon washer?

I don't know, but those are good points to consider.

It's not that I'm a complete idiot and can't tell whether the pipes are copper or steel, pvc or metal, etc. they actually aren't my pipes.

Thank you for your reply.

Generally, threaded metal piping which has been brazed or welded or threaded and assembled with thread seal tape should not leak if the wprlk was done to a good standard.
As the pipes are existing and had heating oil in them previously, I suggest that there may be plastic or rubber components which have degraded, causing the leaks.

I look forward to your posting of the pipe details and, if you can manage it, photos of the leaky pipes.

Regards,
Tony