Rb25 Engine Flush

[Room42]

As far as the head goes it will be given to a shop for reco and have the face shaved and slightly thicker head gasket will be used. If i can get away with leaving the bottom end i will but if not I will rebuild it. I have a R34 neo sitting around so I may have to swap it in... I didn't want to because of having to re-wire...

Mate even with your head you can check that your self. I don't know the head straightness specs or the surface ra offhand but they will be available somewhere. The surface finish isn't as important with a stock gasket as they take up the imperfections in the head. Just run a straight edge across it and use a feeler gauge to check it. Save yourself 500 to 700 bucks and clean it yourself and check everything yourself. Even as far as checking the valve seats and possibly using some grinding paste on them if necessary is an easy task. There are tools out there for removing the valve springs and checking valve spring tension. Get a baby bench grinder with a wire wheel to clean up the valves. You could get away with spending less than $300 on tools and parts to freshen up the head and refit it to the engine. I paid for a head to be reco'd once and now I would never do it. Only thing I'd pay for would be the surface grind if it needed it. Generally they don't, sometimes they do.

[StevenCJR31]

So I have an rb25det with blown head gasket and has been sitting for a while and is still in the car. I am about to pull the head off and do the job but is it possible for me to "flush" the engine in order to get rid of the oil milkshake that is all through the bottom end????

do you know why the HG blew in the first place?detonation? overheating?corrosion of the coolant passages?you will have to sort that out as well otherwise you could pop the next HG that you put on it

[StevenCJR31]

Mate even with your head you can check that your self. I don't know the head straightness specs or the surface ra offhand but they will be available somewhere. The surface finish isn't as important with a stock gasket as they take up the imperfections in the head. Just run a straight edge across it and use a feeler gauge to check it. Save yourself 500 to 700 bucks and clean it yourself and check everything yourself. Even as far as checking the valve seats and possibly using some grinding paste on them if necessary is an easy task. There are tools out there for removing the valve springs and checking valve spring tension. Get a baby bench grinder with a wire wheel to clean up the valves. You could get away with spending less than $300 on tools and parts to freshen up the head and refit it to the engine. I paid for a head to be reco'd once and now I would never do it. Only thing I'd pay for would be the surface grind if it needed it. Generally they don't, sometimes they do.

^^ this is good advice

[koe]

Coming from a kid that resorts to name calling means about 2 thirds of stuff all. P.s the head flange only got here on Friday.

wow you guys clearly got it wrong.The process of cleaning does require rinsing it off and

everyone cleans there parts with some form of petroleum product.You have the rinse it and let it dry after you clean it tho.....

[Room42]

wow you guys clearly got it wrong.The process of cleaning does require rinsing it off and

everyone cleans there parts with some form of petroleum product.You have the rinse it and let it dry after you clean it tho.....

Mate if you read the thread they are talking about putting petrol or similar through an engine from the oil filler and draining it out the bottom. Read before you post. And you sure as shit wouldn't "rinse" an engine after putting petrol or diesel through it. And what happens to your engine if you let it dry after said rinsing? No one in their right mind would start a washed, rinsed and dried engine. Oh my god I am wasting my time here.

[Rolls]

Yeh you keep saying that but we're not skinning cats.

What is significantly different? They both turn the motor. Cranking uses the power of the starter motor to do so and then once it's running the engine can use it's own power. Essentially the only difference is the RPM.

Cranking it vs running it has one key difference, there is no downwards force on the bearings from the pistons firing. There will still need to be oil pressure and oil that can stop the bearings touching, but no where near as much.