blue smoke on start up !

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Merlot man
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blue smoke on start up !

Post by Merlot man » Sun Sep 17, 2017 1:39 pm

Hello all
I've a 95 2.5 TD bus 133000 miles .
lately went I start her up first thing she puffs out blue smoke but after a minute it clears and all is good , i've disconnected the breather pipe from the induction pipe and fitted an oil catch can [old plastic milk bottle ] and blocked the bung but to no avail , so am I now to assume that the turbo is on its way out ?
I don't mind too much replacing it if its the culprit but what else could it be ?
Any and all advice greatly appreciated
Brian
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mikeonb4c
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Re: blue smoke on start up !

Post by mikeonb4c » Sun Sep 17, 2017 6:23 pm

If it was turbo would it not continue to put out smoke even when engine is warm? Is it lumpy on start-up? Is it worse on first start of the day (when engine is cold). Its getting to the right time of year for iffy glowplugs to reveal themselves.
Merlot man
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Re: blue smoke on start up !

Post by Merlot man » Sun Sep 17, 2017 7:16 pm

Thanks for the reply mike
Its starts ok and I've fitted new glow plugs in july so I don't think its those .
It only smokes when cold then clears up to be fair
Brian
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Re: blue smoke on start up !

Post by Northern Bongolow » Sun Sep 17, 2017 7:21 pm

probably valve stem oil seals, when the engine is turned off one or more valves are left open into the chamber oil may run down into the chamber and then be burnt off when first started up. piston rings worn or sticking, the stuff below may help clean and free them off if they are sticking with carbon build up
try this stuff or similar.
correct engine oil is important, what are you using now. cheap fuel wont help, use the best you can afford, an enhancer will give a better burn helping to keep internals cleaner.

http://www.halfords.com/motoring/engine ... ment-325ml.
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Northern Bongolow
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Re: blue smoke on start up !

Post by Northern Bongolow » Sun Sep 17, 2017 7:22 pm

is this smoke just unburnt fuel when the auto (choke) cold start is operating, if yes then its normal.
Merlot man
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Re: blue smoke on start up !

Post by Merlot man » Sun Sep 17, 2017 7:34 pm

Thanks for the reply NB , I use Castrol magnatec 10w40 every 4/5k miles and add 50ml of millers every tank .
last oil change I gave it a flush and added slick 50 to help improve things .
The stop smoke looks promising though , I assume you use it for every oil change ?
How big a job is it to replace the valve stem oil seals ?
Its embarrassing as much as anything but I still would like to sort it out .
Brian
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Re: blue smoke on start up !

Post by teenmal » Sun Sep 17, 2017 8:39 pm

Dont rule out "Dripping/weeping " injector/s,and the dreaded head gasket.
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mikeonb4c
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Re: blue smoke on start up !

Post by mikeonb4c » Sun Sep 17, 2017 10:18 pm

Northern Bongolow wrote:probably valve stem oil seals, when the engine is turned off one or more valves are left open into the chamber oil may run down into the chamber and then be burnt off when first started up. piston rings worn or sticking, the stuff below may help clean and free them off if they are sticking with carbon build up
try this stuff or similar.
correct engine oil is important, what are you using now. cheap fuel wont help, use the best you can afford, an enhancer will give a better burn helping to keep internals cleaner.

http://www.halfords.com/motoring/engine ... ment-325ml.
Does this kind of thing come on suddenly though? :roll:
teenmal
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Re: blue smoke on start up !

Post by teenmal » Sun Sep 17, 2017 10:27 pm

mikeonb4c wrote:
Northern Bongolow wrote:probably valve stem oil seals, when the engine is turned off one or more valves are left open into the chamber oil may run down into the chamber and then be burnt off when first started up. piston rings worn or sticking, the stuff below may help clean and free them off if they are sticking with carbon build up
try this stuff or similar.
correct engine oil is important, what are you using now. cheap fuel wont help, use the best you can afford, an enhancer will give a better burn helping to keep internals cleaner.

http://www.halfords.com/motoring/engine ... ment-325ml.
Does this kind of thing come on suddenly though? :roll:

This usually happens when the oil drainage return ports /ways get obstructed /blocked and the oil builds up in the head/cover.
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Re: blue smoke on start up !

Post by JoeC » Mon Sep 18, 2017 5:58 pm

When were the valves last checked / adjusted? If never then may be worth getting these checked.
I got mine checked (no smoke issues though) and the engine was smoother afterwards. And that was on a TD with 83K KM's.
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JulesMartin
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Re: blue smoke on start up !

Post by JulesMartin » Wed Jun 17, 2020 9:16 pm

Can I just re-open this posting as it applies to me. recently probably since the warmer weather on start up it's put out quite a bit of blue smoke that clears almost straight away and it is lumpy more than it used to be again for only a few seconds. I'm using the best fuel and the recommended oil. The head was done round christmas time and its been absolutely fine since then. I am wondering if it may be the valve stem oil seals and I'm not sure now if they were done when the head was skimmed and i did find a bag of them in amongst my bits and bobs so maybe they did get neglected by the engineers. question, does anybody know if they are doable in situ. years ago I used to do them on morris minors by bringing each cylinder up to TDC and levering the springs down using the top of the piston to stop them from dropping down but this is a different kettle altogether. Any advice as always really appreciated
Martin
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Re: blue smoke on start up !

Post by maxi_77 » Fri Jun 19, 2020 10:11 pm

I have been told blue smoke is oil based and as reported clears as the engine warms up, white smoke is caused by water and is most likely a head problem. Constant blue smoke pretty worn engine, black smoke some form of over fuelling
White diesel Bongo
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