Going to change my oil on saturday and was just wandering if I need to use any type of engine flush in the oil to clear things out. I was told my oil was a bit on the thin side and has lost it's viscosity so wasn't sure if flush would be needed or not.
Cheers
Dave

 

no need to flush

 

I seem to recall API David once saying in big capital bold letters "never use engine flush in a Subaru".

 

No need m8, just go for a drive to warm up the engine then drain it out.
I've only ever used flush on a C reg fiesta that had done short trips all its life, the oil in that was more like mayo.

Dipster

 

Definately don't use flush. These engines have a habit of grinding the big end to death just after an oil change as it is.

Guide (© Greasemonkey)

1) Warm engine
2) Drain old oil from sump
3) Remove old filter
4) Pre-fill new filter with fresh oil. Fill and keep filling until it won't take anymore.
5) Apply new filter
6) Apply new washer to sump plug and tighten
7) Fill engine oil filler to mid-way between two holes on the dipstick
8) Disconnect crank sensor
9) (Preferably) remove spark plugs
10) Dry crank engine at least until oil pressure light extinguishes - ideally for 20 seconds or so more.
11) Refit spark plugs
12) Refit crank sensor plug
13) Start engine, leave to idle for a good minute or so before driving for oil pressure to stabilise
14) Check sump plug and filter seal for adequate tightness/leaks
15) Go for slow drive until engine fully warmed
16) Top engine oil to upper hole
17) Check sump plug and filter seal for adequate tightness/leaks

The plug removal bit is going a bit far maybe, and the crank sensor is under the alternator.

 

Well said Sir, I won't bother with the capitals again,

BUT, IT IS A VERY BAD IDEA,

sit in a dark room until the urge to flush goes away..............

Oh well I guess I just can't help myself !!

David APi Engines / APi Impreza

 

Thanks for the advice, I'm now sitting in a darkened room until morning when I will start my quest!!
Cheers again for the advice.

Dave

 

Oh dear.................

I have an my94uk running 284bhp and 282lb/ft. It has 123,000miles and last week I had a sticking tappet due to clogged oilways. I used Forte motorflush and the noise just went away. It now holds better oil pressure and appears to be more responsive (could be placebo)
So if this was the wrong thing to do, what should I have done? Just changing the oil didn't help.

 

You should be ok...
They tend to go pop straight after the oil change, so if its gonna happen it will do it sooner rather than later.

*****

 

Cool, thanks mate. I've done 500ish miles since and no probs.

 

You're VERY lucky, we've just rebuilt an engine where 'xxxxx' flush was used - it made 400 yards and blew a big end. The poor owner wanted to sue the garage and the flush manufacturer, but once the 'flushers' turned up with a book the size of a phone directory about the spec and quality of the said flush there was little point in pursuing a case through the courts.

There is too much at stake for the 'flush' Co. to go to court and lose, so they'd fight forever. Better to move on and put it aside as one of life's lessons.

David APi Engines / APi Impreza

 

How do you dry crank the engine??

Cheers

Andy

 

Remove the crank sensor plug and the engine will turn over with out fireing.

Look here to see photograph of sensor plug. Pretty good write up on an oil change as well.

 

Cheers Rokay, that's all I needed to know

Back on topic, so engine flush is a definate no no?? Scooby specialist we've been taking the car too does it every time.

 

how soon after flushing oil do they go bang, i flushed mine the other weak, all is fine, however i do think that the engine has got louder rattle maybe just me paranoid all the time,

 

Sort of depends on many factors; if your engine is well on the way to tired then very probably quite soon after. If it's in tip top condition you'll probably get away with once or maybe twice.

Not much of a Scooby Specialist who doesn't know not to flush a Subaru is it?

Best not to risk flushing it.

David APi Engines / APi Impreza

 

There is a very well known place in the West Midlands I go to that uses engine flush on my car in services and I have never had any problems. This place is highly regarded as a trusted tuner and dont think that they would use it if they thought it would damage the engine.

 

Are we talking the gallon of "flushing oil" here, or the Forte stuff that goes in with a cheap oil for a few minutes and is then drained out?

 

In 5 years i've flushed my engine once.... never bothered since. What is the exact reason for not using it David? And can the cause of the engine failures be linked to the flushing.... seems that engines like to die after oil change anyway so are the ones that failed after using a flush definately because of that.

Just intetrested in the reasons why...as i've said i don't flush now when changing oil and won't be in the future.

Tony.

 

the 500 ml additive, would never ever use the gallon stuff

 

The Subaru turbo engine is particularly susceptible to low viscosity oil. I.E. you should only ever use 10W upwards NEVER 5W or 0W. Thus, it follows that super thin solvent based oil to flush it out is lower than 10W and there's no more to be said really.

The Forte flushing 'stuff' is basically auto transmission fluid, which will do the same job AND is A LOT cheaper. Take a trick from us and if you must flush - to clean out rattlly hydraulic lifters - put 1/2 litre of ATF in the engine [ after draining out 1/2 litre ] run for 200 miles and then refill with proper oil and a new pre-filled filter.

A whole gallon of 'flush' would be suicidal on a Subaru.

David APi Engines / APi Impreza

 

I was warned off flushing on a clio williams once. The reason was that the flush can stay in the hydraulic tappets causing major problems.

If your changing the oil frequently enough (and now the history of the engine)there should be no need to flush.

BTW I always flush the toilet..!

Jason

 

With modern synthetic oils flushing is not necessary as the detergents in the addative pack are more than sufficient.

Cheers
Simon

 

Cheers David, understand now. Not sure about the above statement tho, i thought Subaru recommend a 5W/40. I'd agree about the 0W.

Tony.

 

I think we've been here before. Certainly 5w is recommended for later cars. If my memory serves me right 2000 onwards.

It's also in the handbooks. Check first.

Cheers
Simon

 

What is the opinion on Redline SL-1 Fuel additives?

http://www.redlineoil.com/whitePaper/15.pdf

 

lol
has your new engine arrived yet bud ? ;-)

 

I'd like to lay bets that engines that have had dead bearings allegedly because of the flush would have gone regardless of flush being used or not. More likely thrashing and using the wrong oil for the conditions its used under.

Still, a well maintained clean engine should not need engine flush, as it won't be dirty or have enough deposits to warrent it. And any hard varnish/ deposits that has occured will never get shifted by engine flush anyway.

 

Having read Corradoboy's instructions (also read somewhere else) I spoke to a local dealer who said that disconnecting the crank sensor then turning the engine over would generate an error code which would then be stored.

He told me that they just pre-fill the oil filter!

Do I understand from API david that this is the same procedure he follows, or does he clear the fault code after disconnecting the sensor?

I would like a definitive answer as I will probably carry out an interim oil filter/service myself on my 03 WRX between dealer services.

Andy

 

Never had a fault code come up ever. Maybe it is stored somewhere but it doesn't appear a problem and certainly never had a CEL light because of the disconnect and spin trick.

Good Luck David APi Engines / APi Impreza