Engine Flush Necessary For Oil Service?

[iuddin90]

As above, just wanted to see what you guys recommend.

If I need to flush the engine before I change oil and the filter. I'm going to take it to National Tyres as it's quiet cheap for labour plus the oil & filter.

[Rich_D]

No, you don't need to do an engine flush and it can do more harm than good

[daza-b]

No, you don't need to do an engine flush and it can do more harm than good

what he said lol

[zimzimmer46]

You'll be doing more harm than good by flushing it.

[F07GT Steve]

Can you chaps explain Y it's a No No to use engine flush when doing a oil change.

I use it as it helps break up the gunky oil that's in the engine

And its some thing a mechanic friend of mine uses.

I do this and have done on all my beemers and never had any engine problems.

So Yes Boys,,, please explain

Sent from my iPhone using Tapatalk - 10-4 Out#

[mit]

Engine flush shoves loads of corrosive agents into your engine to break down the oil and flush it out, also breaking down any protective seals etc. Also removes any oil residue clinging to bits of the engine. These are vital in the first few seconds when your engine starts, otherwise you have metal grinding on metal until the oil gets a chance to pump around the engine. It was beneficial on older engines that weren't made to such tight tolerances, where you'd get a build up of carbon etc on various parts that would then not get properly lubricated, but these days the engineering is so precise that this kind of thing doesn't happen.

Rather than an engine flush you're better off changing your oil, going for a decent blast on the motorway and then changing your oil again.

And Steve, regarding your anecdotal evidence of never having problems when using this on BMW engines, I've never used it on BMW engines and also never had any problems

Edited January 15, 2013 by mit

[simonlpearce]

For what it cost for an oil change these days (circa £50) your better off just getting the oil changed every 4-5000 miles.

[Individual 330ci]

I defo wouldn't advise it. My mate had it done in his highly tuned Fiesta ST in September... It was sounding a bit tappety before and the garage actually recommended the flush saying it would help the tappety sound..... So he lets them do it- 3 days later we're driving round the m25 on the way to Trax and silverstone, about 20 mins into the journey pooling on the inside lane- 6am in the morning then BANG. Loads of smoke, car running like a sack of s**t, limped over to hard shoulder, popped bonnet, oil and metal everywhere- it had put a rod through the block where, it emerged that they had not drained the flush properly and it mixed with oil and went sludgy....

Fortunately they admitted liability and put a new engine in it for him, which he was very lucky to get done as it was only a back street garage!!

So after that little story I'm sure you won't be considering it further lol.

[mit]

For what it cost for an oil change these days (circa £50) your better off just getting the oil changed every 4-5000 miles.

And you're even better off just sticking to the service schedule and not worrying about it at all ;)/>

Edited January 15, 2013 by mit

[quackers]

And you're even better off just sticking to the service schedule and not worrying about it at all ;)/>

Yep. Oil is very good nowadays. well, most of it :-)

[brixtoninmate]

when i brought my e46 i used engine flush then filled with cheap oil from halfords got it hot blasted up A3 and back for 15 miles got back and drained straight away making sure i drained every last drop out then filled with a good 0-30 oil ,car is sweet as a nut after it being in there for 4 months went on a 800 mile round trip chequed oil before and after trip apart from not using or lossing a drop the oil still looks and feels nice and clean.

but now i know what engine flush can do ill be staying well clear .

lisson to the people on here mate they give good advise and no what they are talking about

[Michael Lam]

I think the general consciousness is that if the engine has been a bit neglected or ran on the wrong oil then flushing is a bad idea.

But if you know the car has been well maintained then it wouldn't hurt, of course this comes back to the "Why bother" if it has been well maintained.

I've had my 325i done twice now with Forte Advanced Formula Motor Flush and each time the flush has gone through the oil has come out pretty dirty, bearing in mind in these respective services Castrol Edge and Mobil 1 oils were used and 12,000 miles were covered.

My car is running sweetly and I know my local mechanic uses them in all of the services and report no problems, they know me and my dad well so they give us a choice on wether to run the flush or not.

all they do is pour it into the oil, run it for 15-20 mins (sometimes a bit longer) and then drain as normal, what I did ask yesterday was to pour a bit of fresh oil into the sump just to wash out any stuff remaining.

I personally think these horror stories come from a combination of things

1. A cheap nasty flush was used
2. The engine was on its way out or fooked already
3. The mechanic didn't follow the instructions correctly
4. It wasn't drained fully which goes back to point 1 using a cheap nasty flush that contains ingredients which will cause a negative effect on the engine.

I've been told by my mechanic and have seen on another BMW forum that Forte's flush has no corrosive agents which will damage seals in the engine.

Forte is the only brand I have experience with so my view is based on this brand of flush but others I can't comment on, what I do know is the chaps who Terracleaned my car have STP Engine Flush on display in there customer waiting area.

[IanG1]

Reminds me of my brothers old XR3i we did an oil change on about 25 years ago.

We put some flush in it and ran the engine till nice and hot and then dropped the oil.

Did and oil and filter change but were confused it took around a litre less oil than it should but carried on regardless.

Next day on his way to work the car started to rattle from the top end and the oil light came on. He had the sense to pull over but no signs of anything amiss under the bonnet but we towed it home anyway.

We decided to drop the sump off to find an inch thick layer of black carbonised sludge stuck to it and the flush had partially dislodged bits of it which then blocked the oil pick up pipe.

We cleaned it all out and put it all back together and luckily we got away with it as it ran fine.

Car had only done 46K and had a service history...........................or so we thought LOL

[Bargain Bucket]

IanG1 has hit the nail on the head. If the engine is dirty inside i.e with baked on oil deposits/sludge on the internals then the flushing agent may well cause large lumps to break off. The deposits/sludge can block the oil pickup or block an oil gallery, thus causing oil starvation which results in severe damage. Never flush an engine that hasn't been flushed on EVERY oil service from new.

[brixtoninmate]

I know for sure the car i have has gone along way between oil changes didnt know when brought it my own fault for rushing in had rocker cover off there was hard bits and sludge i cleaned out what i could.im just about to do an oil change im confused isvit better to leave the engine like this or is it better to do a flush then remove the sump to clean anything out.

Or maybe flush clean out sump then cheap oil warm up then drain and fill with good stuff

[Michael Lam]

If there was a lot of sludge some say a dedicated flushing oil might be better.

Forte Motor flush is a very good one IMO, maybe worth pouring a can in and leaving it for 30 mins, the bottle actually says for neglected cars leave it for 30-40 mins as opposed to the normal 15-20 mins.

Then leave it to drain real good, for peace of mind I got my mechanic to pour in bout half litre of oil to drain out the sump until it was clear then filled up with the good stuff.

My engine is in good nick though so perhaps for your case, maybe an idea to fill it up with cheap oil then drive it around for a few miles then drain again to fill up with good stuff.

What oil have you got in it at the moment?

[Ginger]

If it ain't broke.........