Injectors

You can't personally adjust them. You could remove them and take them to a diesel injection specialist for checking/adjustment.
 
Its unlikly your fuel pump is at fault,if you suspect the injectors remove them,you can test them yourself,the end of the injectors has little holes which become blocked with carbon, remove one at a time hold away from yourself crank the engine the injector should spray a fine mist in a measured squirt, if it dribbles at the end of the squirt or is not mist it is at fault,a word of warning here the fine mist is at very high pressure and can easy penertrate skin and eyeballs,so point it away from yourself.
 
If it's lots of smoke even when the engine is warm, then an injector test is indicated. But if it's just whilst the engine warms, I recommend no action. There are downsides to removing injectors, and 3-4 seasons is light usage by most standards. Mine are the originals - 10 years in place and not removed once during that time.

PWG
 
thanks guys. There is grey smoke all the time. However, if other posts are correct and grey smoke means too much fuel then the injectors perhaps are not blocked but too large???? I will give it a blast this weekend and if no joy, remove the injectors for inspection. The weather looks stormy this weekend (Denmark!) is it classed as a good run if I run the engine at full power, in gear! while tied up? We have double pole pole box moorings here so no danger of damage to the boat. What do you think?
 
Hi swanny,there is no substitute for a good long fast run at sea,i suspect the engine is underused and needs a blast to clear things out,half an hour on the mooring wont do it IMO,while the weather is bad get yourself to the libary and gen up on diesels,you can save yourself a lot of money,even a nice shiney red beta wont like standing idle for weeks at a time.
 
If the engine itself is OK and has good compression etc. The most likely cause is a worn fuel pump or even a broken spring in the FP. Take it and the injectors to a diesel specialist and have them set up properly.
 
You mention in your initial post that following your overhaul the engine has produced grey smoke from day one. This was despite having fitted new injectors so it seems unlikely, given also that the engine starts readily, that the injectors are at fault for producing unburned fuel which is giving a grey exhaust and a film of oil on the water.

The engineer carrying out the engine overhaul suggested that the fuel pump was in need of overhaul and was responsible for the grey smoke. Do you have a good reason for discounting his advice? Does that lack of confidence in his advice indicate that you also have concerns about the standard of the overhaul?

Others have suggested low compression as the cause and that would seem to me most likely.

A compression test will give an initial indication of where to start looking.
 
I have gray smoke from MD2. A long run does not get rid of it. It has good compression. When I took my injectors to be checked the bloke said it is timing. Unburnt diesel is the result of injecting fuel too late. To adjust the pump needs shims adding or removing. You need to check the dimension from the face of the engine (with the pump off) to the cam. Should be +/- .2 mm. The dim is printed on the pump. I took mine off and there where no shims so I need to add some. Also I do not have a depth mike or vernier to check the dim yet.

Not a difficult job but you need the right equipment.
 
I took mine off and there where no shims so I need to add some. Also I do not have a depth mike or vernier to check the dim yet.

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Wee bit of a contradiction Boyo.... If your timing is late then adding shims lifts the pump increases the cam clearance and makes the timing later so you most certainly do not want to do that if you already consider the timing to be late...

Are you quite sure the grey smoke is from combustion and not steam.

Grey to white smoke is usually produced at start up and clears once all cylinders get going. These engines can produce copious amounts of steam which is more visible in the winter. Some Diesel lubricating oils can make grey smoke but I have only seen these on the big marine engines when things wern't quite right .
 
Mac77 has got it I think, this is not a wear issue, its a set up issue, get someone who knows that they are doing to adjust the timing to the correct setting.
 
This gets more interesting by the minute! Thanks for all your replies. I tend to concur with the newish injector theory - carbon build up would restrict fuel not increase - I think! I guess I don't want to believe my engineer because it would be expensive to do so! The steam issue is an interesting one. I have on occasion put my hand over the exhaust while running to see if my hand got wet from condensed steam (or burnt due to heat!) It definately is smoke although I have to say that it does appear more smokey during eh colder months. I guess it is possible it is a mix of both. However, before I invest (not the right word with a boat I know) money on a new engine I will get an engineer to check the fuel pump and timing to see if it makes a difference. I probably could do it myself but I would at the same time create two other problems to deal with, such is my way. I love the look of my old boat - Contest 36k 1979 - she looks very purposeful and seaworthy amongst all the 'plastic fantastics' in the marina but that same purposeful look fades a tad when I start her up and the breeze fills the neighbours cocktail cockpit party with grey smoke. Keep it coming!
 
Hi swanny,my point was if the injectors are clogged with carbon it would give the same effect as to much fuel ie drops instead of spray,i know its a pain knowing what to look at first especialy when it costs money,but i would start at the injectors and work back.this forum is full of advice some good most not so good,you takes your choice.
 
I had both my engines fully reconditioned including the injector pumps. From day one one engine ran perfectly the other produced whitish smoke all the time. I put up with this for two years and tried various remedies until I spoke to an engineer who knew what he was talking about.
I advanced the pump as far as it would go on its slot mountings and the problem cured instantly.
 
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