Both the Tilley DN. 250 and DN. 250A irons contain several asbestos washers. Many brands of liquid fuelled irons do; though not all. If keeping the irons as part of a collection, I would simply leave the washers as they were and not disturb them. However, I wanted one iron to be fully clean to be able to show it and light it. Thus a replacement of the washers became a small project. I ordered some Garlock 2500 3.2 mm thick gasket to make 3 spacers and some Bakelite 4.5 mm washers for the inner rear washer replacement. Some larger washers turned out to be able to be replaced with Primus stove large washers (5 needed). The internal wick that sits in the spirit cup was replaced with 5 mm fibreglass wick woven into a chain sinnet to make it thicker. I masked up and had a strong breeze from behind whilst I removed and bagged the old washers for disposal. Here are some photos. The DN. 250 after the overhaul. The Broken Handle that came with the iron and was replaced with a new old stock handle. The burner needed two Primus stove large washers. The three internal washers shown here can be replaced with small M4 brass washers. The rear bolts keep the metal washers (DN. 250A does not have these), but you need to replace the two outer asbestos 4.5 (ID) by 12.6 (OD) and 1 (T) with red fibre washers 5 (ID) 12.8 (OD) 1 (T) These washers go between the handle and the cover. Replace 3 groups of two asbestos washers 3.5 (ID) 10 (OD) 3.2 (T) with three single Garlock 2500 gasket washers 3.5 (ID) 9.5 (OD) 3.2 (T). Use a hole punch to cut the outer washer and drill the hole for the three small bolts. Use three more Primus stove large burner washers stacked upon each other. ou need to use a large drill bit to help center the washers whilst putting the handle on. The new handle needed to have three holes drilled out for the retention machine screws. Spirit Cup This is located inside the iron and you need to replace the existing asbestos 18 mm flat wick with fibreglass 5 mm cord chain knotted or a new Tilley torch wick (non-asbestos). Must be wired in place to stop movement. Washer Temperatures This is what I found out about the materials. The red fiber washers max temp is 110C. The Garlock 2500 (green) has a continuous max temp of 205C and lastly the Bakelite ‘high temperature resistant’ washers vary but probably around 200C but sometimes up to 285C. Some of these can withstand higher temperatures for short duration. Firing It Up I gave it a go and it worked well. I really don't know how long the washers will hold up for but it seemed Okay. A hard photo to get. It works and job done.
Thanks @Tony Press @JEFF JOHNSON @ROBBO55 for the comments. Indeed it will be interesting to see how the washers last over time. I did test the primus washers and the garlock 2500 material with a propane blowtorch (about 1200 deg C on average) for ten seconds and both were frazzled. However, none of the washers are in direct flame so maybe they will last a while.
Very impressive mate, I do like these Tilley irons. I think they look amazing in one's collection. Congratulations mate and Very well explained
Thanks @Buggerlugs I agree they look good. The DN. 250A tank is a slightly different colour too as well as the chromed cover. The big thing is these Tilley irons all need a lot more pre-heating than a Tilley lantern.
A job to be proud of, well done. I have one in good working condition with the chrome on the sole plate still intact. I do however want to access the innards to possibly clean up the `burner` Would I be correct in saying I would only need to disconnect the tube at the on/off valve (with respect to seals) to gain access as any other screws / bolts are for holding the various parts together. I am not doing a complete disassembly just trying to access the innards.
