Puff of smoke on start up,E240 2004 petrol/auto

[scarfacetm1984]

Recently came across this.Had a car for about 2 years,had no problems with it driving.Was doing about 5 miles a day.
Changed the job ,so started doing around 30-40 miles a day,and then the problem started.
Every time car started after stood for about 10 hours or overnight,car gives a good blueish puff and then all clears out.
Need help to identify the problem.
Thank you in advance

 

[Trinitom]

could be a few things, how many miles does the car have?
it could be stem valve seals, worn cylinders/piston rings.

 

[scarfacetm1984]

could be a few things, how many miles does the car have?
it could be stem valve seals, worn cylinders/piston rings.

Hi,thanks for quick reply.Car has done 110k which I would think is nothing for the Merc.
So should expect huge bill?

 

[Trinitom]

well that depends how well the engine is being maintained.
i would start with a compression and leak-down test, and go from there.
or you can try using an approved heavier engine oil to mask the problem.

 

[Stocious]

Valve stem oil seals it’s indicative of

 

[Stocious]

Is was it a well maintained car?

 

[scarfacetm1984]

Other thing,one of exhausts been hanging,and smoking started almost at the same time,might be coincidence

 

[scarfacetm1984]

Is was it a well maintained car?

Yes it was,like i said in my last post can it be a condensation collecting over a time,probably not,just don't know

 

[Trinitom]

condentation its normal and white in color, also dissipates very fast.
oil its blue in color, and dark usually related to bad fuel burning.

 

[scarfacetm1984]

condentation its normal and white in color, also dissipates very fast.
oil its blue in color, and dark usually related to bad fuel burning.

The smoke turned out is white in colour,gives a puff of it and clears straight away.but again started only when the exhaust was sorted and started doing higher mileage per day

 

[E55BOF]

Oil takes a lot longer to reach full temperature than coolant does. Doing five miles a day, it was never getting there. Now that you are doing more mileage, the oil is getting hotter, and therefore thinner, and more can seep down the valve stems into the combustion chambers through worn valve stem seals when the car is standing overnight. I think that is your problem.

 

[Trinitom]

The smoke turned out is white in colour,gives a puff of it and clears straight away.but again started only when the exhaust was sorted and started doing higher mileage per day

then surely its just steam, have a look on youtube and compare.

 

[scarfacetm1984]

Oil takes a lot longer to reach full temperature than coolant does. Doing five miles a day, it was never getting there. Now that you are doing more mileage, the oil is getting hotter, and therefore thinner, and more can seep down the valve stems into the combustion chambers through worn valve stem seals when the car is standing overnight. I think that is your problem.

During ownership had a week when had to do more miles,never had a puff of smoke.Now it's like puff and all clean.Been several times to london and back several times,no overheating engine sounds smooth and quiet and pulls as 2.6 engine should.

 

[scarfacetm1984]

then surely its just steam, have a look on youtube and compare.

Seems like it.Noticed , it's different all the time,had no smoke few times at all..

 

[grober]

Valve stem seals harden with time and are the most likely cause- the car is just showing its age- perfectly liveable with for now To replace them means removing the rocker arms but with compressed air and a few specialist tools can be done without removing the cylinder head/s