Monday 16th September 2013 - War & Bugs

Post by **Jeff** » Mon Sep 16, 2013 11:09 am

I am 50% sure I've now fixed the air in fuel issue! Having tried _everything_ there was only one place left air could realistically be entering - the final bleed screw itself. I didn't really think it could be the source - it looked fine - copper washer present and correct - but I applied some of my Loctite 572 gunk to it anyway then left the engine alone for 24 hours. Started it this AM and it jumped into life instantly. No sign of any air.

I can't believe that was the cause (if that was the cause). I've replaced most of the hoses, and the lift pump, and removed and re-connected all connections, repeatedly... I dread to think how many hours I've spent down in the engine so far this year because of one little bolt!

Meanwhile we had a little excitement recently when HMS Somerset parked next to us in the anchorage. We had a 24/7 armed guard watching us for a few days so I slept sound in the knowledge that if we developed a problem, they'd probably pop round and knock on the door and tell us. We moved away however partly due to the strong wind forecast (which is now upon us and causing us to list violently) and partly due to HMS Somerset's twin Rolls Royce gas turbines which they forgot to turn off at night.

And then we found some little white insects. I'd seem them here and there about the place, but since we got back aboard last week, there were definitely more of them. I asked the Natural History Museum bug identification forum for help and it turns out we had 'book lice' which like warm, damp environments, lots of cracks and crevices and dried foods. Clearly they evolved to like boats then! We found quite a few under our basket we use for bread. I promptly freaked out and felt itchy all the time, so Rose took command and we emptied all kitchen lockers, deep cleaned them - and everything in them and proceeded to throw out absolutely everything we had that wasn't totally sealed up. Then sprayed insecticide liberally and especially in cracks and crannys. Then went out for the day.

Since then we have seen no bugs.

Here's some pictures...

HMS Somerset - Our New Neighbour

HMS Somerset While I Work

Book louse (booklice, barklice, 'psocids' Psocoptera) - about 1mm long

Discus · Post by **Discus** » Mon Sep 16, 2013 2:01 pm

Bloody hell, that's a bit close! Guess they aren't following their own ' stay 100 metres away at all times' rule. Hope none of the ratings choose to take a slash off the side - they could hit your decks from there!
Damn copper washers can be a pain in the rear. I have now decided that copper washers should be treated as single use only as they lose their ability to deform after a couple of times. You can try re-annealing them in an emergency but its not that effective IMHO. Order a selection box of copper washers off eBay and replace as necessary. So far on our Bukh, ALL of the fuel leak issues and the leaking oil cooler were as a result of leaking copper washers. In fact, the fuel leak off the lift pump was so bad that it has ruined the rubber on the rear engine mount which means we have the joy of replacing all four mounts over the winter period - yippee!!
Just to say, I would take your work view any day of the week than my usual view (classroom)!

Keep on trucking

Rob

Post by **Jeff** » Tue Sep 17, 2013 8:14 am

Another perfect engine start this AM after another 24 hour wait. My concern now is what I can do to keep myself busy now that bleeding fuel lines is off the agenda (I am just kidding!)

Makes sense re copper washers. Can't believe I didn't consider the effects of work hardening - that washer has been crushed so many times now it's probably porous. But I also am surprised it never ever showed even the slightest hint of leaking fuel, even after pressurising the system and leaving it for hours. It leaked air in, and not fuel out, which I might expect from a flexible coupling that could deform differently under pressure or suction - but not a solid parts system like a bleed screw. Anyhow I learned my lesson. Should have listened to Sherlock Holmes about 'if only one possibility remains, no matter how bonkers, then that must be it'.

One thing though - I found so many potential weak points in all of this that I'm glad it happened in a way. I know the fuel lines are sound from tank to engine now.

Copper washers on order... oh! Hang on. When I went to Pirtek they gave me some 'dowty washers', saying they were the best thing since sliced bread. Have you heard of them? More expensive than copper, but probably not requiring replacement after each use:

search.ebay.co.uk/dowty+sealing+washers

What do you think?

Btw, what do you teach Rob?

Terry T · Post by **Terry T** » Tue Sep 17, 2013 9:31 am

Jeff wrote:Another perfect engine start this AM after another 24 hour wait. My concern now is what I can do to keep myself busy now that bleeding fuel lines is off the agenda (I am just kidding!)

Makes sense re copper washers. Can't believe I didn't consider the effects of work hardening - that washer has been crushed so many times now it's probably porous. But I also am surprised it never ever showed even the slightest hint of leaking fuel, even after pressurising the system and leaving it for hours. It leaked air in, and not fuel out, which I might expect from a flexible coupling that could deform differently under pressure or suction - but not a solid parts system like a bleed screw. Anyhow I learned my lesson. Should have listened to Sherlock Holmes about 'if only one possibility remains, no matter how bonkers, then that must be it'.

One thing though - I found so many potential weak points in all of this that I'm glad it happened in a way. I know the fuel lines are sound from tank to engine now.

Copper washers on order... oh! Hang on. When I went to Pirtek they gave me some 'dowty washers', saying they were the best thing since sliced bread. Have you heard of them? More expensive than copper, but probably not requiring replacement after each use:

search.ebay.co.uk/dowty+sealing+washers

What do you think?

Btw, what do you teach Rob?

Hi Jeff nice to have you back posting !! dowty washers ...... We use them in the Navy ,super seals . Somerset must have a stack of 'em onboard ........ Ask 'em for a few

Remember though they have a "rubber" seal so not so good in a fire

Post by **Jeff** » Tue Sep 17, 2013 9:35 am

Thanks T. Is that why copper's used on the engine seals then? For fire risk prevention?

Discus · Post by **Discus** » Tue Sep 17, 2013 10:36 am

Never heard of Dowty washers but they look good. Terry is right, they may not be suitable for an enclosed engine compartment as they could fail if there was a fire. I would also be interested if the rubber part was diesel resistant as long term exposure to diesel can rot anything with a high natural rubber content ( I suspect they will be ok if Pirtek use them). Regarding your bleed screw, I can imagine that air gets in but diesel doesn't get out as the fuel is a significantly larger molecule than air. This will be exacerbated if your fuel tank is below or at the same level as the engine as you don't get the benefit of gravity feed helping to maintain pressure in the system. When we realised our oil leak was from the oil cooler, it looked as if the seals on the oil feed pipe were leaking. I contacted Bukh in Poole to get the washer size and they were fairly adamant that it was unlikely to be the copper washers. On removal, they were scored on both sides and slightly the wrong size so were overdue for replacement. The fuel unions to our lift pump and fine fuel filter are also copper washers and leaked significantly, although not letting any air in as the fuel tanks sit above the engine. I managed to tighten them- but really had to hold my breath as the amount of force required was significant, and could have caused some damage to the fittings. Mind you, I have just re read this post and it might be the most boring post anyone has ever written. Nothing like a verbal lobotomy before lunch!!! Oh yes, in answer to your question, I teach Geography but do not own a pair of cords or a tweed jacket with patches on the elbows.

Rob

PS Hi Terry, how are things with you?

Post by **Jeff** » Tue Sep 17, 2013 10:50 am

Ah OK. I know the molecule size of diesel is remarkably small - hadn't considered air was smaller.. or that the difference between sealed and not sealed in my case must therefore have been around the dimensions between than of an air molecule and a diesel one! That's amazing! But must be the case.

I still can't work out though, how, when I closed off the fuel line each time, to avoid suction back to the tanks, air was getting in. I would expect diesel would also have to leak out wouldn't it?

My Grandad was a geography teacher (in fact he still is, quite often, I find (sorry Grandad

)) and I don't think he has cords or jackets with patches either. His tectonic plates are rubbing a bit in his knees now though - perhaps he should have had patches in his trousers.

Terry T · Post by **Terry T** » Tue Sep 17, 2013 11:22 am

Not really sure as Rob has pointed out that Dowty seals are really suitable for your long term use with diesel /rubber union . We use to used them on air systems but their durability was fantastic . give them a ring .

. We are back in Plymuff 4 a few weeks to hide from the non event bad weather

. We are being hoisted out for a week next Monday for anti fouling etc then back in for the winter and hopefully some winter sailing

Post by **Jeff** » Tue Sep 17, 2013 11:32 am

Yeah where is this crazy wind we're forecast? Had the odd strong gust but nothing major. Windguru says it's going to pick up to 40 knot gusts this afternoon. We shall see!

Winter sailing - sounds good!

Discus · Post by **Discus** » Tue Sep 17, 2013 12:19 pm

Jeff wrote:Winter sailing - sounds good!

.....sounds cold to me

Terry T · Post by **Terry T** » Tue Sep 17, 2013 12:29 pm

Jeff wrote:Yeah where is this crazy wind we're forecast? Had the odd strong gust but nothing major. Windguru says it's going to pick up to 40 knot gusts this afternoon. We shall see!

Winter sailing - sounds good!

Ah ha here it comes bloody windy here now !!

Rob I have full foul weather gear for winter sailing ,, a trago tee shirt and shorts

complete with a baseball cap which I wear back to front.

Post by **Jeff** » Tue Sep 17, 2013 12:43 pm

Yeah it's hitting here now too. Yeuch!

Can picture you Terry

Terry T · Post by **Terry T** » Tue Sep 17, 2013 12:47 pm

Jeff wrote:Yeah it's hitting here now too. Yeuch!

Can picture you Terry

I can picture you too ........ All snugged down in your fully enclosed wheelhouse . Not like Isabella eh ? BTW has she now been sold again ?

Post by **Jeff** » Tue Sep 17, 2013 12:56 pm

Yeah the wheelhouse makes a big difference.

Isabella - lot of interest recently, but not sure if sold yet.

Discus · Post by **Discus** » Tue Sep 17, 2013 1:12 pm

Terry T wrote:Rob I have full foul weather gear for winter sailing ,, a trago tee shirt and shorts complete with a baseball cap which I wear back to front.

Sounds very 'street' Terry

at least it's not a string vest, track suit bottoms and a can of lager!

Enjoy the wind folks - just hoping its gone by the weekend!