Smoky Volvo

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alancollins

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My TAMD41P diesel has done 400 hours. It starts instantly, runs smoothly and delivers full power. It burns no oil in a typical season of 80/90 hours and use no coolant. Yet I get a lot of grey smoke on start-up, although this reduces somewhat at normal running temperature. This has only appeared over the last couple of seasons and I have not done anything different. Any ideas?
 
This summer, after filling up with fuel at a different place to the norm, mine smoked quite badly.

On refilling at Gosport, the smoking was cured. Problem is, unlike filling up at a Shell station, you don't know what grade fuel you're taking on.

I find that dosing with Millers Diesel Plus Sport 4 helps reduce smoke, and also makes the engines run quieter. Quite noticeably so.

I'd try filling up elsewhere and see if there's any improvement.
 
white/grey smoke on start up is usually unburnt diesel, had the same problem on yanmar 350's 2 years ago. Tried everything new injectors, pumps, timing in the end Yanmar fitted pre heaters and problem was solved. Strange how mine started at a similar number of hours, none of the specialists ! could come up with a reason why but the heaters which cut out once the engine reaches normal temps (about 5 mins depending on air and water temps) worked brilliantly, virtually eliminated smoke totally.
For first few years had no smoke at all but it was so bad before fitting heaters that my wife did not want to leave a berth if there were people around, she found it rather embarrasing leaving people in a white fog.:)
 
41s with only 400 hours how old are they? I would imagine 1995 at the youngest. If they have had very light use in previous ownership they could have glazed bores. A compression test could answer that question.
 
DAVIDO said:
41s with only 400 hours how old are they? I would imagine 1995 at the youngest. If they have had very light use in previous ownership they could have glazed bores. A compression test could answer that question.
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I generally say away from Green engines unless answer is generic, and this is........No, no, no!

Thought I had left all this gasoline head thinking behind in the U.S. Please do not start it over here.

Correct way to determine condition of power cylinder of a diesel engine is a blow by test, NOT a compression test. Very very rare to see a manufacturers compression spec for a diesel engine therefore no data to check against.

If you graph compression of a diesel engine during running using a modified cylinder head you see little difference in the compression from newly broken in out to engine requiring overhaul. However a simple blow by test tells you the whole story about engine health.

There is a real simple test of the power cylinder which requires zero instrumentation, called the 'low earth orbit test'. Run the motor until nicely warmed through and gently uscrew the lube oil filler cap, without holding it too tightly. If oil cap is blown out of your hand and goes into low earth orbit, power cylinder is goosed, simple as that!

Engine surveyors in the US obsessed with compression checking, often causing problems where none previously existed. Used to remind so called hot shot certified technicians they needed to revise their mind set...........Gasoline is for girls.
 
Latestarter1 said:
I generally say away from Green engines unless answer is generic, and this is........No, no, no!

Thought I had left all this gasoline head thinking behind in the U.S. Please do not start it over here.

Correct way to determine condition of power cylinder of a diesel engine is a blow by test, NOT a compression test. Very very rare to see a manufacturers compression spec for a diesel engine therefore no data to check against.

If you graph compression of a diesel engine during running using a modified cylinder head you see little difference in the compression from newly broken in out to engine requiring overhaul. However a simple blow by test tells you the whole story about engine health.

There is a real simple test of the power cylinder which requires zero instrumentation, called the 'low earth orbit test'. Run the motor until nicely warmed through and gently uscrew the lube oil filler cap, without holding it too tightly. If oil cap is blown out of your hand and goes into low earth orbit, power cylinder is goosed, simple as that!

Engine surveyors in the US obsessed with compression checking, often causing problems where none previously existed. Used to remind so called hot shot certified technicians they needed to revise their mind set...........Gasoline is for girls.
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Latestarter1 I love the way that you give the most technical responses where appropriate yet go back to basics with equal aplomb, keep it up I always look out for your posts.

Happy New Year.
 
Tappets?

alancollins said:
My TAMD41P diesel has done 400 hours. It starts instantly, runs smoothly and delivers full power. It burns no oil in a typical season of 80/90 hours and use no coolant. Yet I get a lot of grey smoke on start-up, although this reduces somewhat at normal running temperature. This has only appeared over the last couple of seasons and I have not done anything different. Any ideas?
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Just possible.

John G
 
I am not familiar with the TAMD41P but have 2 TAMD41As. These are fitted with a system which closes a "choke" on the exhaust actuated by a solenoid which is signalled from the throttle linkage. looking from the front, this is on the left rear of the engine and when you close throttle to a tickover is designed to limit the smoke. In my case when I bought the boat neither of these solenoids were working and I got a lot of smoke when cold especially when at tick over but none when warm and under power. Everywhere I ask professionally I am told this is normal so don't worry. You may well find that things are improved on the later engines and they may be different but it's worth asking if your engine has the same slow runing choke system and if it does is it still working as it should. Either way unless you have smoke when warm under power it's not a problem but it can make you unpopular in marinas and locks......
 
BoatMike, to the best of my knowledge, the selonoid choke system was only fitted to the 41A. 41B onwards had increased compression ratios which combated the smoke.

I too have TAMD41A's and the chokes do not operate. Many have told me its quite common and not to bother fixing as they are useless anyway! Mine smoke when cold and can be embarrasing in marinas! Fine when warm and under load though.

John.
 
trouty12 said:
BoatMike, to the best of my knowledge, the selonoid choke system was only fitted to the 41A. 41B onwards had increased compression ratios which combated the smoke.

I too have TAMD41A's and the chokes do not operate. Many have told me its quite common and not to bother fixing as they are useless anyway! Mine smoke when cold and can be embarrasing in marinas! Fine when warm and under load though.

John.
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Interesting Trouty. I have in fact got both my chokes working now but as the boat is out of the water I won't know if it's made any difference yet. Yes I think that whatever you do there will still be smoke when cold. I don't think the solenoid chokes were ever meant to combat this. It's when you go to tickover when warm it seems to make a difference to me at least. One solenoid worked at first and the other didn't. The one that smoked at tickover was the one that didn't work so I think it might do something but I agree its a crappy idea. Someone else said adding "Millers Diesel Plus Sport" makes a difference. Never heard of it. Have you?
 
Im surprised to hear your 41P prefix engine smokes as it was the last of the run and a very smoke free friendly engine when new.

Id say you havea problem somewhere, but to diagnose it via this forum is like playing pin the donkeys tail!

You must check the obvious and be sure the colour of smoke is related to the fault you think it is, white/grey is unburned fuel when not under load, are you sure its not steam?

Id start with injectors, then pump timing, then pump diagnosis, comp tests, valve clearances and a blow by test hich will indicate worn bores and valves that dont seat.

A blow by test can b carried out relatively cheaply by buying a small air compressor and rigging up some tool to sit where the injectors should be, you will of course have to rotate the engine so that each cylinder is on compression, ie both valves closed.

Id check the intercooler for large deposits of oil , maybe you have a turbo oil leak.

If you have sea water entering the engine via the CAC then that shows like smoke from the exhaust.

Come back to us.
 
Thanks guys. I'll try the Millers Diesel Plus Sport 4 and also the Italian tune-up, before moving onto anything more technical.
 
alancollins said:
Thanks guys. I'll try the Millers Diesel Plus Sport 4 and also the Italian tune-up, before moving onto anything more technical.
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Take another look at the post from a person who KNOWS about Green engines.

Use of snake oils is pretty pointless if your base hardware is known not to be smoky.

Most serious comment is regarding CAC condition when was it last serviced.
 
Latestarter1 said:
Take another look at the post from a person who KNOWS about Green engines.

Use of snake oils is pretty pointless if your base hardware is known not to be smoky.

Most serious comment is regarding CAC condition when was it last serviced.
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OK I have to ask.....What the hell do the initials CAC stand for?
 
boatmike said:
Oh right! One o them...... Ain't got one ta!
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Oh yes you have!

TAMD41A (Turbocharged Aftercooled Marine Diesel)

Seeing as you were not aware that your engine has them.........Likely that they have never been serviced......However thats just a SWAG (Scientific Wild Arsed Guess)
 
Latestarter1 said:
Oh yes you have!

TAMD41A (Turbocharged Aftercooled Marine Diesel)

Seeing as you were not aware that your engine has them.........Likely that they have never been serviced......However thats just a SWAG (Scientific Wild Arsed Guess)
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LS 1 you beat me too it, nearly as good as the call i got some years back.

" Hello, our engine needs a service" yes I can do that, what make and model is it please,

"Sorry ive no idea but its green", I went to take a look it was a Ford Sabre!
 
whatamisakatomaka!

Latestarter1 said:
Oh yes you have!

TAMD41A (Turbocharged Aftercooled Marine Diesel)

Seeing as you were not aware that your engine has them.........Likely that they have never been serviced......However thats just a SWAG (Scientific Wild Arsed Guess)
Click to expand...

Thank you Latestarter. I have always thought this forum an excellent source of information and appreciate your correction. Perhaps either you or Volvo Paul (whose contribution only adds sarcasm so far) would go further for me.

I am in fact an engineer and understand the principle of intercooling/aftercooling in general terms but having just moved from sail to power my practical knowledge of diesel engines is primarily related to auxilliaries not big 6 cylinder green lumps like this. In terms of servicing, the engines seem to be generally in good condition with clean oil, new air filters and only a small leak from the fresh water circulating pump which I have to deal with. So far having purchased the boat (Aquastar 33) in Essex and driven it home to Portsmouth I have no experience apart from that and would welcome any advice forthcoming. The only documentation I have is the usual "owners manual" that is about as much use as a chocolate teapot and says nothing about servicing aftercoolers. Since bringing the boat home and lifting out of the water I have been working on getting "Peregrine" my 37ft catamaran, presented well to sell her. Yesterday I took a deposit from a nice French gentleman who has committed to purchase so Yipee!! I can now turn my attention to getting "Appela" up to scratch. Up to now I have not had time to research detail. Hence my embarrassing lack of understanding regarding jargonese.

Question. Is there a publication or proper service manual I can buy at reasonable cost for this engine somewhere that will outline the main features of maintaining it without reference to that annoying phrase "refer to a competent service agent"? Local Volvo agents are not helpful in this respect at all and it's clear that DIY is not encouraged.

Failing this can someone give me a brief description of what servicing the beast actually requires please?
 
After a previous post which was a joke (boatmike) I will bother to help you as no doubt it will help others on here too.

The 41s problems is all relative to use and age, along with how its been looked after over its life, you would never see 40,000 hours from a 41 let alone many other leisure rated marine engines.

Id start with a full service, change oil, fuel air breather filters and impellers, belts, anodes if it has them you may find one in the heat exchanger and oil cooler, coolant, gearbox oil.

Make a general inspection of the mounts as you have a heavy boat, the vertical posts break, there is a mod available to fit larger diameter posts and new rubber mounts.

Check the valve clearances, and maybe remove the injectors for testing as 41s dont have the best bosch injectors out there, ive fitted hundreds over the years and believe me outright new ones make a big difference to a 41.

Hope that helps you out boatmike, this forum can be really good you know.
 
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