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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????

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Any coolant that has gone past the pistons in the oil galleries etc will be in the sump. So draining the sump will suffice unless i have missed something? After running the engine at operating temp for a while it will burn off any remaining coolant/vapour too.

Umm if its been sitting for a while, there would now be rust in 1 or more cylinders, as soon as you start it, depending on how bad it is, you could damage the rings/pistons and bores.

Or has it simply blow a water to oil part of the gasket?

DO NOT run any kind of degreaser through your engine. :domokun: Not kero or diesel or anything. If the water has diluted and mixed with the oil (milky) then there is a chance that the bottom end bearings are rooted. You should have a look at them and while you are there you can wipe it all down and assemble it all properly with assembly lube. Clean out your oil pump and prime it properly. FFS putting degreaser through an engine then just dumping new oil in it and hoping for the best is stupid. But by all means to the blokes that suggested it, the next time you do an oil change drop 10 litres of diesel through your motor then put the oil in after. See how long it lasts. And yes there could be some rust buildup. To the op, I'm not having a go at you, just make sure you do it properly.

you may not want to do the diesel thing, it does have the potential to end badly. if its been sitting around for ages you could strip the engine down and get it chemically cleaned by an engine builder.

This. It will end badly. :rant:

DO NOT run any kind of degreaser through your engine. :domokun: Not kero or diesel or anything. If the water has diluted and mixed with the oil (milky) then there is a chance that the bottom end bearings are rooted. You should have a look at them and while you are there you can wipe it all down and assemble it all properly with assembly lube. Clean out your oil pump and prime it properly. FFS putting degreaser through an engine then just dumping new oil in it and hoping for the best is stupid. But by all means to the blokes that suggested it, the next time you do an oil change drop 10 litres of diesel through your motor then put the oil in after. See how long it lasts. And yes there could be some rust buildup. To the op, I'm not having a go at you, just make sure you do it properly.

you obviously havnt tried it . . ive done it many times with numerous motors over the years and havnt had ANY fail nor has it affected the longevity of said motors, the amount of crap that ive gotten out of engines is unbelievable and when you have done it properly you dont contaminate your fresh clean oil with built up crap in your bottom end

you obviously havnt tried it . . ive done it many times with numerous motors over the years and havnt had ANY fail nor has it affected the longevity of said motors, the amount of crap that ive gotten out of engines is unbelievable and when you have done it properly you dont contaminate your fresh clean oil with built up crap in your bottom end

Nor would I ever. I guess when I went to tafe years ago to do my mechanics apprenticeship, all the stuff they taught me about engine building was a load of crap. And all the blokes I worked with just guessed their way through engine rebuilds. The fact that you would admit you have done this is ridiculous. Next time you assemble an engine use petrol for assembly lube. Geez I'm wasting my words... :rolleyes:

Edited by Room42

Nor would I ever. I guess when I went to tafe years ago to do my mechanics apprenticeship, all the stuff they taught me about engine building was a load of crap. And all the blokes I worked with just guessed their way through engine rebuilds. The fact that you would admit you have done this is ridiculous. Next time you assemble an engine use petrol for assembly lube. Geez I'm wasting my words... :rolleyes:

geez im glad my mind isnt as closed as yours. . .just because you have done an a mechanics apprenticeship (did you pass?)doesnt mean you know it all, BTW i have built a number of "A" series , "L" series and RB motors with no issues at all :thumbsup:

Nor would I ever. I guess when I went to tafe years ago to do my mechanics apprenticeship, all the stuff they taught me about engine building was a load of crap. And all the blokes I worked with just guessed their way through engine rebuilds. The fact that you would admit you have done this is ridiculous. Next time you assemble an engine use petrol for assembly lube. Geez I'm wasting my words... :rolleyes:

DO you honestly think you are the only mechanic on the forum, get off your high horse. Whenever i rebuild a diesel, i run kero through it for 15 min 1500rpm free rev, obviously you dont rebuild diesels otherwise you would do the same.

To the OP i would drain the oil, and refill with 50%cheap oil, 50%kero and run it for a few min then drain it while it is hot. If you are worried about the bores being rusty, then you are up for a rebuild anyway, so might as well give it a go..

DO you honestly think you are the only mechanic on the forum, get off your high horse. Whenever i rebuild a diesel, i run kero through it for 15 min 1500rpm free rev, obviously you dont rebuild diesels otherwise you would do the same.

To the OP i would drain the oil, and refill with 50%cheap oil, 50%kero and run it for a few min then drain it while it is hot. If you are worried about the bores being rusty, then you are up for a rebuild anyway, so might as well give it a go..

^^this

Nor would I ever. I guess when I went to tafe years ago to do my mechanics apprenticeship, all the stuff they taught me about engine building was a load of crap. And all the blokes I worked with just guessed their way through engine rebuilds. The fact that you would admit you have done this is ridiculous. Next time you assemble an engine use petrol for assembly lube. Geez I'm wasting my words... :rolleyes:

mongggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg!

geez im glad my mind isnt as closed as yours. . .just because you have done an a mechanics apprenticeship (did you pass?)doesnt mean you know it all, BTW i have built a number of "A" series , "L" series and RB motors with no issues at all :thumbsup:

DO you honestly think you are the only mechanic on the forum, get off your high horse. Whenever i rebuild a diesel, i run kero through it for 15 min 1500rpm free rev, obviously you dont rebuild diesels otherwise you would do the same.

To the OP i would drain the oil, and refill with 50%cheap oil, 50%kero and run it for a few min then drain it while it is hot. If you are worried about the bores being rusty, then you are up for a rebuild anyway, so might as well give it a go..

more than one way to skin a cat buddy.

LOL!

watch out everyone hes a Tafe man!

Tafe graduates run this bitch yahear!!

ill say it again you close minded fool.

"there is more than one way to skin a cat"

and apparently your skills in the one form of cat skinning you know seem to be lacking due to your education.

or did you want to twin turbo this topic? :nyaanyaa:

watch out everyone hes a Tafe man!

Tafe graduates run this bitch yahear!!

ill say it again you close minded fool.

"there is more than one way to skin a cat"

and apparently your skills in the one form of cat skinning you know seem to be lacking due to your education.

or did you want to twin turbo this topic? :nyaanyaa:

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.

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