Using POR15 to seal the tender water tank

As advised in the instructions for Kit 7 I have purchased POR15 tank sealer

But 'I'm not 100% clear on how to proceed

- Do you apply the POR15 with the tank lid off - first blocking off all the applicable screw holes and sealing up on the outside any large joints (thinking blue tack?)
- Does it have to be applied by pouring in and then sloshing about or can it be applied copiously by brush?
- What do you then do with the lid, coat the inside separately, and then attach it into the tender? If that the case, then how do you seal up this new gap without pouring POR15 in and sloshing about (coating the water pump pipes etc...)

I'm confused, please can someone help me with a 'noddy' description of the steps to follow

I have been coping well with the instructions until I got to Kits 7 & 8 and these do not appear as clear to a steam novice, like myself

No responses, so I decided to just crack on.....  

So, first of all, I plugged all threaded holes within the water tank with scrap bolts

Then I degreased the surfaces and applied POR15 Metal Prep (which appears to be some form of rust inhibitor/acid)

Masked up on the outside the tank top holes and other holes.

Applied masking tape inside the tender to paint the POR15 up to (just below lid holes), then applied blue tack along all the joins in the hope that this would prevent any major leakage onto the bench





Then I sat the tender raised inside a silver foil tray to minimise any possible spillage/clean-up



Then I poured the POR15 in and worked into all the joins and painted the sides and the tank lid



Coming back to it every 15 minutes to work the POR-15 around, particularly into the joins with a brush.

No major leaks beyond the blue-tack, however some seepage at the front bottom edge of the tank

After 90 minutes, I have drained off the excess and will now wait for it to dry or at least become tacky before removing the masking tape and blue-tack.

So far so good

This is how I did mine works really well