How to fix water leak from the temperature sender?

[NorthernLad59]

My Stag has developed a very slow, the occasional drip type slow, leak from where the temperature sender fits to the back of the left hand cylinder head. I took the attached picture with a boroscope. I was wondering what type of washer should be used (if any) or if folks fit PTFE tape or some sort of sealant when fitting the sender unit. I thought it best to seek advice before taking the sender unit out. What I've learnt from owning a Stag for nearly 2 years is "never overtighten anything" which is tempting in this case .

Richard

[jbuckl]

Remove , drain, clean, dry.

use loctite flange sealant

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[sujitroy]

I replaced the ali washer with a copper one. It is a parallel thread but gets crappy with age so the threads need a good clean

[Rob Heath]

Pardon my ignorance (never had a V engine before) but which side is the left hand? Looking from front? I have a leak from the rear of the left hand looking from the front and wonder if this is the same problem.

Rob

[NorthernLad59]

When I said left hand side I meant the "near side for a right hand drive car", so not the same side. To track mine down I wiped down all the surfaces to remove oil, water etc and then used a endoscope/boroscope type camera to see the leak. I use a dual lens unit made by Depstech with a dedicated screen. It cost around £70 and has proved very useful for all sorts of things. Originally I bought it to check my cavity wall insulation !

[jbuckl]

Pardon my ignorance (never had a V engine before) but which side is the left hand? Looking from front? I have a leak from the rear of the left hand looking from the front and wonder if this is the same problem.

Rob

Usual U.K. way to describe vehicle left and right is when you’re sat the drivers seat.

not looking from the front.

stag engine rotation is described as clockwise when looking at the front though.

[DJT]

Something regularly missed, or ignored, is that the cylinder heads have LH and RH cast into the front, which helps with identifying which side is which.

[Rob Heath]

Thanks all, so my water leak is not the temperature sender.
perhaps I’ll invest in an endoscope to have a look.
Rob