How do i do an engine flush - 2004 Subaru Forester

You could try performing an oil flush on the engine. The hydraulics in the head can be clogged up with oil that has broken down, preventing them from fully actuating. I have done a number of engine flushes myself using a blend of fresh engine oil and diesel fuel which went a long way to silencing noisy hydraulic lash adjusters/lifters. If your engine has never had an oil flush then it would be well worth it. I was VERY skeptical about the diesel flush (it'll blow my engine up, it's gonna destroy the rings and burn a ton of oil etc) but it made me a believer. p.s. I have compared diesel fuel to the off-the-shelf engine flush treatments, and I'm 99% sure it's the same stuff just a lot more expensive... I have done a write up myself for another forum and have received positive feedback on my flush method -
http://www.mightyram50.net/vbulletin/showthread.php/2954-Why-didn-t-I-Think-Of-That?p=49688&viewfull=1#post49688

you don't want it to, as the flushing oil has little consistancy , and it will only need a 5 min flush , then replace oil, then have to prime the oil pump as have had it flushed

The most common way to flush an engine is by draining the oil. Put 1 gallon of engine flush treatment in. Start vehicle and allow to run for 5 minutes. Drain the flush treatment, and add the recommended amount of oil.

no you have to drop your gas tank clean it out. if you didn't start then just clean gas lines. if you started it then you need a new engine. the sugar gets in the engine and turns to syrup. bad engine.

drain coolant system locate heater cores hoses going through firewall you need to buy the radiator flush kit at any auto parts stores. remove heater cores hoses from one end or buy extra long heater hoses same size as heater core hoses in vechicle at auto parts store use the flush kit when you flush through one of the heater core hoses let the other hose drain in a drain pan when you use home garden hose use low water pressure dont use garden hose to the max or you will rupture heater core. your best bet let radiator shop flush whole coolant system. because heater cores hoses are in a tight spot.make sure engine off if you just going to flush out heater core only .after flushing heater core good time to replace heater core hoses.if job too hard or complicated let radiator shop flush out radiator the engine block and heater core because if radiator stopped up or engine block stopped up the gunk and rust will reenter plug up heater core.if you tight on money you can flush out your own radiator.drain out radiator using large drain pan. remove top radiator hose and remove bottom radiator hoses connect to water pump.use garden hose with flush kit part with water pressure not too high put garden hose to top radiator hose run water until clear water run out bottom radiator hose in drain pan,the flush out engine block remove thermostat.if you had another spare thermostat housing with RTV SILICONE SEALANT THAT HAS SET UP INSTALL THERMOSTAT HOUSING BACK TO ENGINE WITHOUT THERMOSTAT FLUSH OUT THE ENGINE BLOCK, WHEN DONE INSTALL NEW THERMOSTAT THEN INSTALL ORIGINAL THERMOSTAT HOUSING WITH NEW ORING WHICH YOU BUY AT DEALERSHIP.IF ALL SOUND COMPLICATED LET RADIATOR SHOP FLUSH OUT COOLANT SYSTEM.

engine valves noises,either oil too thick.engine oil and oil filter need changing if oil dirty contaminated with gas and antifreeze which will dilute make oil too thin causing low oil pressure causing lifter noise dirt get trapped in lifters orifice holes cause lifter noise.make sure engine not overheating that will cause lifters noise.if engine oil been changed and oil filter been changed either lifters worn or oil passages in the cylinder head need flushing out.i use a can of engine flush.drain out pint of old engine oil out of crankcase.pour engine can of flush in oil crank case start engine let it idle good 10- 15 minutes let the engine flush out sludge build up out the engine cylinder block.now if engine oil is too thin and diluted you need to drain out two quarts and add two good quarts.because if engine oil is too thin diluted it will cause engine bearing failure quick.after you finish the engine flush then you do your oil and oil filter change.after another 300 to 500 miles change oil filter again or get a garage flush out engine if you do it wrong you will damage engine bearings make sure engines has correct oil level. reason i say drain out pint old oil from crankcase and add can of engine flush to keep from over filling crankcase.now if your oil is too thin diluted you need to drain out 2 quarts and add 2 new quarts to keep engine oil getting too thin.engine rinso will thin out oil and flush out sludge carbon build up out of engine block oil passages.when you are done.then you need to change oil filter and engine oil change. do leave engine rinso mix with new engine oil it will thin out oil enough do engine bearing damage.make sure before doing engine flush that oil level on engine oil dip stick at full mark.

No, they are just trying to rid you of some money. If the engine oil is dirty it just needs changing not a flush. Change your oil/filter every 5,000 and forget about an engine flush. Notice this is a body shop telling you about your engine. See anything wrong with that? They may know body work but they for sure do not know engines. If this is a V6 have the cam belt replaced at 110,000 miles as this is an interference engine. If it is a 4 cylinder it has a chain so nothing for you to do.

Hunnybunny has typed in a step by step way of flushing it at home.

If you are talking about an engine oil system flush, NO

If you take care of your car, change oil at recomended miles or time, use good quality oil and filters, then a system flush will do nothing for you but lighten your wallet.

Engine & Transmission Flush

You might have been told, by your dealer or mechanic that your engine oil or transmission fluid are very dirty, & an engine or transmission flush, is recommended. The flush will clean the engine or transmission, & those will last longer. This is only part true a clean engine or transmission will last longer, but I'm not sure that flushing them is the best way to clean them.


What Is An Engine Or Transmission Flush?

Flushing is forcing high pressure of fluid against the normal flow of the fluid. In simple words if the normal flow is left to right, the flush would force the fluid right to left.

This is done by connecting a machine that will force special solvents back through the engine and transmission. The idea is that by forcing cleaning solvents backwards through the system, it will get all the junk and garbage that has formed over time and "flush" it out of the system. In theory this sounds very good, but in practice, it can be dangerous.


The Dangers of Flushing your Engine or Transmission

Flush machines force high pressure cleaning solvents back through the engine and transmission and clean out some of the accumulated junk that has formed, so far all is good. Now the problems start, engines have small passages and galleries through which oil or automatic transmission fluid flow and there are one-way valves that keep the fluids from backtracking for whatever reason.

By using an aggressive cleaning procedure like flushing, large chunks of accumulated sludge are broken off and forced backwards through these galleries and valves and, more often than not, lodge tightly and block them. This cuts off the normal flow of the fluid and causes lack of lubrication in an engine and abnormal or no shifting in a transmission. The results are expensive repairs, or more often, engine or transmission replacement.

That's my knowledge about the subject, hope it was helpful,
Joe.