To flush or not to flush

  • Yes, if it's an old high mileage engine

    Votes: 1 14.3%
  • No, never, it's really bad

    Votes: 4 57.1%
  • yes or no - doesn't make much difference

    Votes: 2 28.6%

  • Total voters
    7

exmed wayne

Well-Known Member
300Tdi Defender
about to fit new turbo in next week or so, and IIRC instructions say -

Drain engine oil.
fill with good quality engine flush run for 10 mins or so and drain again
remove oil filter...etc. etc.

I always remember engine flush to be 250ml-500ml added to old oil before draining?

What's your thoughts and technical opinions on engine flushes
and are there any brands that are better / worth avoiding?

Cheers
 
300Tdi Defender
about to fit new turbo in next week or so, and IIRC instructions say -

Drain engine oil.
fill with good quality engine flush run for 10 mins or so and drain again
remove oil filter...etc. etc.

I always remember engine flush to be 250ml-500ml added to old oil before draining?

What's your thoughts and technical opinions on engine flushes
and are there any brands that are better / worth avoiding?

Cheers
i have never heard of a need of engine flush prior to fitting a new turbo (and i fit turbos on vehicles every other day )
however they do recommend when changing out a turbo.... new oil and filter also new air cleaner this covers your warranty if the turbo was to fail as the first question they ask is did you do these simple tasks ......... most get caught out as they never changed the air cleaner who would of thought this voids warranty

as for engine flushing additives stay away from them you could block an oil gallery ..... and i agree with this fellow in the vid as i have experienced it with other vehicles i work on

 
i have never heard of a need of engine flush prior to fitting a new turbo (and i fit turbos on vehicles every other day )
however they do recommend when changing out a turbo.... new oil and filter also new air cleaner this covers your warranty if the turbo was to fail as the first question they ask is did you do these simple tasks ......... most get caught out as they never changed the air cleaner who would of thought this voids warranty

as for engine flushing additives stay away from them you could block an oil gallery ..... and i agree with this fellow in the vid as i have experienced it with other vehicles i work on



Thanks mate.
I'll double check instructions when I'm home, but I seem to remember it saying to do a flush to clear out any old crap and clear the galleries.!
and something about a 2nd oil and filter change 100 miles after fitting the turbo?

I'm keen to do a good job, so new turbo + new air filter + new oil and filter + new oil feed and Drain pipes - that should cover it.

Your thoughts are much appreciated.
 
Thanks mate.
I'll double check instructions when I'm home, but I seem to remember it saying to do a flush to clear out any old crap and clear the galleries.!
and something about a 2nd oil and filter change 100 miles after fitting the turbo?

I'm keen to do a good job, so new turbo + new air filter + new oil and filter + new oil feed and Drain pipes - that should cover it.

Your thoughts are much appreciated.

different manufactures have many instructions specially if it comes from over seas ..when i get back to work on monday i will dig out one of them .it mentioned something about holding the turbo impellor while some one starts the engine to allow the engine to prime oil to the turbo before it spins LOL ..instead of saying disconnect ignition relay spin engine using the starting motor and crank over engine aproxx 10 seconds

do you still have the EGR active ?
 
different manufactures have many instructions specially if it comes from over seas ..when i get back to work on monday i will dig out one of them .it mentioned something about holding the turbo impellor while some one starts the engine to allow the engine to prime oil to the turbo before it spins LOL ..instead of saying disconnect ignition relay spin engine using the starting motor and crank over engine aproxx 10 seconds

do you still have the EGR active ?
:D
Don't think I'll be following the Chinglish instruction to hold the impellor - did it specify 1 finger & thumb only, to avoid pressure damage?

EGR was gone when I bought the defender and I've fitted a stainless blanking plate with EGT sensor.

I was planning to prime turbo with the supplied syringe of oil, and crank the engine round using a ratchett, like I did when I checked the rocker clearances.....I take it there's a much better method?
 
:D
Don't think I'll be following the Chinglish instruction to hold the impellor - did it specify 1 finger & thumb only, to avoid pressure damage?

EGR was gone when I bought the defender and I've fitted a stainless blanking plate with EGT sensor.

I was planning to prime turbo with the supplied syringe of oil, and crank the engine round using a ratchett, like I did when I checked the rocker clearances.....I take it there's a much better method?


turning the engine by hand is very slow and as long as your bum hole points to the ground you wont build up enough oil pressure to reach the turbo

on engine start up the turbo will have a few thousands rpm as its pushed via the exhaust expanding gasses as it sees a load

compared to using the starting motor to push oil around ..with no load cranking speed only with no load

the starting motor trick has been known also to prime oil filters as most people pour unfiltered oil into the centre of the filter prior to fitting cross contamination
 
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:D
Don't think I'll be following the Chinglish instruction to hold the impellor - did it specify 1 finger & thumb only, to avoid pressure damage?

EGR was gone when I bought the defender and I've fitted a stainless blanking plate with EGT sensor.

I was planning to prime turbo with the supplied syringe of oil, and crank the engine round using a ratchett, like I did when I checked the rocker clearances.....I take it there's a much better method?
cranking the engine wont do much good just prime the turbo ,start engine let it idle for a min sorted, if you change oil regularly you wont need a flush engine should be relatively clean, an old unserviced petrol would most likely be gummed up
 
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cranking the engine wont do much good just prime the turbo ,start engine let it idle for a min sorted, if you change oil regularly you wont need a flush engine should be relatively clean, and old unserviced petrol would most likely be gummed up
Thanks again JM :)

I already changed oil and filter once I took the old turbo off....while waiting for it to come back.
Old oil was really thick and black, and when I poured the new oil in through a funnel, it almost overflowed.
I didn't think I was pouring it in overly quick, so thought maybe the drain galleries might be gunged up a bit?
 
Thanks again JM :)

I already changed oil and filter once I took the old turbo off....while waiting for it to come back.
Old oil was really thick and black, and when I poured the new oil in through a funnel, it almost overflowed.
I didn't think I was pouring it in overly quick, so thought maybe the drain galleries might be gunged up a bit?
no thats normal oils got to run down past the push rods then along cam gallery to sump, it would be black, if you look inside filler cap it should be fairly clean if though wet with black oil
 
no thats normal oils got to run down past the push rods then along cam gallery to sump, it would be black, if you look inside filler cap it should be fairly clean if though wet with black oil
Fair one.
I had the cover off about a month ago, to check clearances with a feeler gauge and it looked fine, or rather nothing caught my eye that looked bad!
 
cranking the engine wont do much good just prime the turbo ,start engine let it idle for a min sorted, if you change oil regularly you wont need a flush engine should be relatively clean, and old unserviced petrol would most likely be gummed up
cranking the engine over wont do much ? please explain
 
Fair one.
I had the cover off about a month ago, to check clearances with a feeler gauge and it looked fine, or rather nothing caught my eye that looked bad!
you can tell when it is theres a thick black gunk coating and sitting in the bottom of rocker box,ive seen a lot of tdis over the years and very few could have benefitted from a flush, though an oil change quite often
 
perhaps, it was terminology the op used so seemed fitting, cranking means just turning the engine over either by starter or by hand or any method like a lever etc
please dont pull the terminology card out ......as it was me who mentioned about cranking speeds way before your time. .... so it apears some only read what they want to read
 
please dont pull the terminology card out ......as it was me who mentioned about cranking speeds way before your time. .... so it apears some only read what they want to read
what? i never read your posts and answered the op in correct terminology
 
I’ve been doing this for years on high mileage petrol & diesel engines...
Drain oil,
replace oil filter,
fill with oil,
add Marvels Mystery Oil,
run for 500 miles,
Drain oil,
replace oil filter,
And fill with oil.
 

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