Thorneycroft 60hp white smoke at start up

Rapscallion

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60hp Thorneycroft produces large quantities of white smoke (not steam) when started, which disappears when warm. Compressions very good, starts easily and runs well, any suggestions?
 

longjohnsilver

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I would suggest that you have a healthy engine, this happens to quite a few older engines due to their design rather than any fault.
 

mtb

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When did this start and has it got worse.
It does as L.J.S. says sound like your engine is ok, the only thing would be to get your injectors serviced, or if your capable test them for correct shut off and leakage also spray pattern .The other cause could be the injection pump causing over injection .
Use a jam jar turn the injector around and make sure it injects into the jar as, at 15 atmospheres it will inject under your skin causing blood poisoning.
You will soon get the idea re break point as the injection should begin and end at that point with out leaving a wet end .Also the spray pattern should be constant and not uneven.
Cleaning of the nozzle is easy but do it with care as the nozzle is quite fine but don't touch or undo the other end or you could effect the breaking pressure .
Hopefully a clean up is all that's required, failing that you will have to get them serviced which will cost £10.00 to £15.00 depending on where you go.
After injectors comes the injection pump expensive this so only do it if the injectors have been done and its still the same.
I always use a Lucas service agent because of quality of service.
Don't forget what L.J.S said older engines do start like this so it could be normal
Mick

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philip_stevens

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If I go back to my steamship (turbine), and diesel days, unburnt fuel produces black smoke, and a lack of fuel/excess air produces white smoke.

If we fired up the boilers with the forced draft fans on low speed or the vanes closed, we ended up with a smoke screen astern. The same with diesels with the turbo blowers either on low speed, or forgotten to start them, we ended up with black smoke from the funnel.

If we put the boiler FD fans up too high-a-speed, we ended up with white smoke.

If you open up the engine very quickly, it produces black smoke until it has wound itself up to governor speed.

So maybe the engine is getting a low amount of fuel until the injector pump warms up and the tolerance decreases with the emphasis on excess air until such time.

regards,
Philip
 

stoo

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I HAVE THE SAME ENGINE IN MY BOAT WHICH ALSO HAS WHITE SMOKE ON START UP AND A SMALL AMOUNT WHEN RUNNING
BUT IS A GREAT STARTER AND RUNS PERFECT SO I DONT BOTHER TO MUCH ABOUT IT

YOU NO WHAT THEY SAY IF ITS NOT BROKE DONT FIX IT

ALL THE BEST
 

oldharry

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As others have already pointed out, white smoke on start up is fairly normal , particulalrly for older diesels. The smoke is actually unburnt atomised diesel fuel, and can be ignored as long as it clears withing 30 seconds or so of start up. If the engine only started doing this recently, then the trouble could be in the cold start mechanism. I do not know the Thorneycroft engines specific systems, but I would start by looking at the cold start system. If glow plugs are fitted and one or more has failed; if there is an air heater in the manifold which is malfunctioning; if there is any other type of cold start mechanism is it working correctly? With glow plugs when 1 fails the engine will still start quite happily, but produce white smoke for around 15 - 30 seconds until the failed cylinder warms up enough to burn the diesel properly. When the second one fails, the engine will become difficult or impossible to start from cold!

I have 2 Perkins Primas: both started perfectly, one produced a puff of white smoke lasting about 10 seconds, the other did not. Cause? Open circuit glow plug.

I have also had at different times to BMC Captains. One started clean, the other smoked for 30 seconds - but in spite of intensive efforts I never was able to get the smokey one to come clean! But both ran totally reliably.
 

Mr Cassandra

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Hi .I have a Yanmar 55hp turbo which give out white smoke for the first 2-3min if reved a bit hard , it then clears ,but uses no oil between servising Is this normal? engin 12years old cheers Bob t

Bob T
 
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