Tools Engine Flush, good idea?

Discussion in 'Tools & Equipment' started by nauest, Saturday 14th Feb, 2015.

  1. nauest Valued Contributor ★ ★ ★ ☆ ☆

    Netherlands Ned Texel
    Hi Guys,

    I have heard some mixed reports about this from various indie garages and DIY mechanics.

    I am considering using engine flush on my Accord Deisel, but will it do more harm than good? (The kind that is added to the oil, idled through, then drained) For example Wynns Engine flush.

    I know these engines are very sensitive to soot particulates and the like (Cam Chains) and my car has been on the standard 12500 mile service interval so far. So I thought a good flush through may be beneficial. The engine has done around 41k miles.

    I am intending on bringing the service interval down to 6000 miles (probably 3000 miles for the first one).

    Would I be better off just running a really short first oil change or trying some flush through?

    Thoughts and experiences, diesel, petrol or any! Thought it would be good to share with everyone.
  2. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
    The question to ask here is do any manufacturers recommend flushing your engine ?

    I think you'll find that the answer to this is "no!".

    What I do when I take ownership of a car is I do several consecutive oil changes in quick succession, say only 500 miles apart.

    The oil itself then acts as the flushing agent.

    I'll post a up pic of the inside of my engine if I can find.
    andy83 likes this.
  3. ArcticFire Club Veteran ★ ★ ★ ★ ★

    Scotland Graham Scotland
    I'm also not a big fan of it but I did do one when I bought my CR-V diesel because at 70k miles I had no idea what the genuine previous oil change history was like and I was also trying to sort a sticking hydraulic lifter.

    But otherwise I would just let regular oil changes with decent oil do the job.
  4. nsxer Valued Contributor ★ ★ ★ ☆ ☆

    A good mechanic on one of the local forums here really recommends regularly carrying out engine flushes on diesel units. He has posted evidence of engines with regular services and the internals where a mess.
    I plan to take his advice going forward
  5. DeviateDefiant Co-Founder Staff Team

    United Kingdom Leo Northants
    Big problem with engine flushes, fuel cleaners and all the rest is they can dislodge long stuck "chunks" of burnt carbon which can naturally cause major issues.
  6. ArcticFire Club Veteran ★ ★ ★ ★ ★

    Scotland Graham Scotland
    That happened when I cleaned my EGR valve and started the engine, we heard a loud crack sound as a piece of carbon must have gone through the system. . Slight brown trouser moment.
  7. Nels Moderator Staff Team

    I agree with @SpeedyGee. I would rather 'flush' the engine with oil.
    You cannot clear all the flushing product out, and it is not formulated to be kind to moving parts.

    However, if the engine oil is particularly dirty, suspect that the oil has not been changed often enough, and you want to use one of these products to clean things out quickly, then don't leave the next oil in there for long. Flush the flushing liquid out with some proper oil and then change that after you've run the engine for a while.
  8. nsxer Valued Contributor ★ ★ ★ ☆ ☆

    surely there is some merit in using these products?
    would they sell if they caused serious damage?

    as my wee Civic was my dad's car it was not used regularly, is low mileage for age of car, would not have been pushed hard as a VTEC engine requires from time to time and i was going to carry out an engine flush this year as i do feel the engine needs a good overhaul. don't get me wrong my dad serviced the vehicle yearly and i done a big service on purchase but i feel the need to do something like this.

    With the family wagon (CR-V) i was planning on doing a flush based on the advice of a mech over here who has seen all the problems with diesel engines and turbo failures etc. he swears by the Forte product and recommends anyone who owns a diesel unit to carry out a flush.
    he provided pics of a well maintained toyota landcruiser with regular service as specified by toyota but the inside of the engine was another story the around of gunk was unreal.

    its hard to know what to do some swear by it others don't ... :Frown:
  9. Nels Moderator Staff Team

    I agree, there is a place for these products. If you need a good clean out in a hurry, then they will do it. Conversely, if you can do a few oil changes in quick succession, you will get a similar effect. It's the same reasoning for changing the oil more frequently than each year/12,500 miles.
    nsxer likes this.
  10. nsxer Valued Contributor ★ ★ ★ ☆ ☆

    fair point on regular oil changes. i won't be servicing my CR-V to honda spec ... 12500 is simply way too long so i will carry out every 6 with the recommended castrol oil.
    but i will still definitely look into engine flushing this year regardless
  11. ampers Club Member ★ ☆ ☆ ☆ ☆

    I inherited an Astra G once, bog standard with 1.6 engine. About 5 years old and about 22k mileage and no service history after 3 years of age and about 20k miles.
    I removed the rocker cover to find a good 1/4" of black thick junk which I had to scrape out. I flushed the engine with a decent flush, refilled with a cheap but correct engine oil and ran for about 100miles. Then did a proper oil service. After that the car did about 4k a year, always short cold journeys and I changed the oil once a year with no problems.
    However, I wouldn't flush unless you really need to, if purely unsure of service history a couple of oil changes in short order should do the trick.

  12. nauest Valued Contributor ★ ★ ★ ☆ ☆

    Netherlands Ned Texel
    Some great input here, cheers everyone.

    My thoughts at the moment are to just go for a couple of very short oil changes.

    The flush may help to get the soot away from the Cam Chains but it sounds like the risk of introducing bigger pieces of loosened dirt make an unnecessary risk.
  13. PhillipM Club Member ★ ☆ ☆ ☆ ☆

    United Kingdom Phillip Rotherham
    Just do as others have said and throw a couple of changes at it in short sucession - the detergent packages in modern oils for diesels are so good there's no real need to risk wear and tear with a flushing oil any more.
    Superman001, nauest and SpeedyGee like this.