Investigation time BukhDV20

benw

benw

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This weekend I will be on board with a view to identify where the cooling blockages are on our Bukh. Have been noticing increasing steam of late, in fact this was pointed out by an unknown yachtie as I entered St Kats this Aug. Just as we were making the critical move to get in the dock he shouted you've got water in your engine! What the hell was I going to do there and then? I shouted back - it's a Bukh!

Anyway that said I am going to explore the various parts of the cooling system already posted on the forum. I wonder whether anyone who has delved into this practically could offer suggestions for socket/spanner/allen key sizes as most tools are on board and can't check.

If I take the exhaust elbow off Volspec have suggested I will most likely need to remove the bolt flange as the rubber pipe will have welded onto the elbow. Also the water injection pipe into the exhaust - are these straight fwd to get off? I know best practise would be to re gasket but I have seen some paste mentioned. Any suggestions?

The gas poker - once off some suggest a new gasket? Are these essential given the relatively low use before Charisma comes off the water for the winter?

And finally....
Have noticed some loss of power at full throttle - could be that we are in need of a good scrub but beginning to think new fuel filter with diesel bug/**** blocking or reducing fuel flow?

Thoughts greatly recvd.

Ben
 
No idea of anything specific on your engine. But, a couple of points. Never hurts to check/change the fuel filters. Always carry spares onboard.

Gaskets..... pastes rarely make a good replacement. Many gaskets can be made form a sheet of gasket paper. If it's just a paper/card type gasket, you can make a replacement from a piece of cereal box, greased both sides. Obviously won't work for exhaust manifold gaskets, or head gaskets.
 
Success! Rarely in my experience do mechanical DIY days go as planned but this weekend has gone very well. I have to say largely due to the extensive posts on this forum I set off from work on Friday eve to the boat feeling positive and empowered to have a go.

My fear has been an increasing output of steam from our Bukh DV20 as well as concern that we may have a dose of the BUG!

As you will know we are in a v big spring range on arrival at the boat she was aground an hour before LW. We draw 4ft so I new we would be well out by LW - a natural opportunity to get in the water for an inspection of the prop etc. Walking around our boat which is on a swinging mooring just up from Woolverstone on the Orwell was a surreal experience prticularly as a lorry ferry passed by some 30ft to port! Back wash proved slightly alarming as I dived for the dinghy.

Problem 1 - prop heavily encrusted with big barnacles, in fact prop shaft and skeg pretty well covered. This was obviously effecting the efficiency and ultimate boat speed let alone load on the engine.

Back on board...
Fuel filter and impeller changed - that was the easy bit, now for some more demanding mechanics! Saturday dawned and I set too with 6mm allen key to remove the 2 bolts securing the 'gas poker'. Yes a fiddly job without removing the flywheel but with a combination of tape, spanners etc both bolts came out. And yes the expected salt deposit revealed itself. Very satisfyingly this was removed and the trepidation of getting the bolts back began to build. However through a bit of patient application everything went back.

Next an assault on the exhaust elbow and injection pipes. Everything came off relatively easily and inspection revealed little. I even took the elbow off the engine block using exhaust paste in the refit.

The result - success, well at least noticeably less steam output plus much improved boat speed.

A coolant flush may well give the icing on the cake but I'm a pretty happy chappy with the results as well as feeling pretty smug I didn't pay somebody else to do it. Although not much of a sailing weekend I am glad I gave it a go.
 
It's invariably not the understanding of what/how to do somethign with an engine, but almost always the application of the liberal dose of the law of S.O.D. This is where you find the bolt heads made of cream cheese, instead of steel and that your favourite 10mm ring spanner is now actually 10.5mm because of over use. I can remember torquing the valve cover down (6 ft lbs) on a motorbike, and the first bolt shearing. Previous owners had done it by hand and the bolt had gone plastic and formed a neck... If the engine is new and not been near salt water and you have the right kit... It's all much easier!!!
 
Go for it Jomo. I was certainly apprehensive particularly as all was completed on our swinging mooring and not with the comfort of being alongside if all went pear shaped.
The forum has been a great source of info and with all that mentally collated I had a clear picture of the jobs in hand.

Once started up it's then a matter of releasing the mooring and sea trialing the work you've done. Alot of it is PMA (positive mental attitude) but I found myself planning the what if scenarios rather vividly as I slipped down the Orwell.

Having completed Tony Brooks Diesel Engine maintenance and electrics course I am more aware of how things work, my capabilities and what can go wrong. Thoroughly reccommend anyone to do a course but more importantly then have a go!
 
Ok you have me feeling like a numpty now, whats a 'gas poker'?:o
I built/marinised/fitted my own engines but thats not a phrase I've ever come across and I have visions of you taking the exhaust off with an oxy-acetylene torch:eek:
 
I have picked this term up from various forum postings. The gas poker is where the cooling raw water from the pump/impeller is injected into the engine head. It seems to be commonly referred to as such and consists of a y shaped fitting with two pipes leading into it. The y fitting sits inside the block and has two injection outlets with a crimped end.
 
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