Port & Polished Head

[RT33]

i was just wondering...does a car that just had the head port and polished consume a lot of oil???

i got my head hi flowed about 5k ago and it seems to have eaten a lot of oil. is that normal? i used turbo light when i had the motor put together. i am going to use mobil 1 within the next couple of days. is it ok to use a full synthetic right now??? i've read that u shoud use mineral oils when you first rebuild a motor.

any advise would be great!

thanks!

[sproosy]

from what you said - you got your head ported and polished.

if you didnt get a full rebuild then you should have to worry about oil.

If your car is chewing oil after getting a port and polish it sounds like they might have done a dodgy job. Take it to a mechanic and geta professional opinion.

Is the car blowing smoke? Any oil leaks you can see on the ground? It could be many things that are making it chew oil.

My car has done 130,000km (RB20DET) and it doesnt chew one bit of oil, has never been rebuilt or looked at.

best of luck dude!

[race_snooze]

I have had my 33 gtst for 2 years, and traveled to QLD and back from Canberra once, many Sydney trips, plus coastal trips as well, also WISD and not once has it ever used any oil. So i think there maybe a problem buddy get it checked out you may have excessive blow by, check the intake pipes for that. Good luck

also do a compression test that may shed some light on the problem, change oil. I use a 10w 50w semi senthtic

Edited December 4, 2005 by race_snooze

[RT33]

the car is now blowing black smoke on full load. there is also an oil leak on top of the engine, the breather hose...what wrong????

[RT33]

never did this untill i got the head work

PLEASE HELP!!!!!!!!!!

[SteveL]

i was just wondering...does a car that just had the head port and polished consume a lot of oil???

<{POST_SNAPBACK}>

Shouldn't affect oil consumption at all (other than perhaps by an increase in performance, but certainly not to the extent of blowing lot's of smoke).

Something else has happened - eg valve guide seals installed incorrectly or not at all (don't laugh, saw that done once by a 'professional mechanic').

You need to talk to whoever did the head work or re-assembled the head.

[hungry6]

I think it's more of the case worn old rings versus new found compression = excessive blow by = oil consumption. Just my view, but I'm not a mechanic. So PLEASE donot quote me on this.

[RT33]

iv also seen an oil leak on the top of the engine. where the breather hose goes. (where you plug in an oil catch can) seems to be leaking from there and spraying everywhere on the turbo side of the engine.

But...what could be causing the black smoke???? where is that coming from????

[proengines]

get a leak down test done on the engine. It sounds like you have a fair bit of crankcase pressure if it's blowing oil out the breathers. Once you have some results it's easier to diagnose what is wrong. Porting the head wont make a difference to the oil consumption if everything was done properly.

[SteveL]

what could be causing the black smoke???? where is that coming from????

<{POST_SNAPBACK}>

Black smoke is not oil burning, but excess fuel (ie rich mixture).

[Craved]

Black smoke is not oil burning, but excess fuel (ie rich mixture).

<{POST_SNAPBACK}>

your right, he needs to confirm that it is black smoke or blue smoke.

black = fuel.

blue = oil.

compression test required for sure.

[RT33]

i was told by a friend that was driving behind me that it looked black, but that was at night... i looked at it during the day and it looks greyish/bluish. i have a feeling it might be loose rings.

i only had the head polished because i needed the exhaust valves replaced because my ex mechanic stuffed up my timing belt when replacing the water pump. i think the rings could've been damaged then???

if it is the rings, i was thinking rebuild??? does anyone with a built motor have any sugestions?

[StageZilla]

get a leak down test done on the engine. It sounds like you have a fair bit of crankcase pressure if it's blowing oil out the breathers. Once you have some results it's easier to diagnose what is wrong. Porting the head wont make a difference to the oil consumption if everything was done properly.

<{POST_SNAPBACK}>

proengines is pretty much exactly on the mark imho. my rb26 had this problem, blowing oil outta the breathers because of a cracked piston ring land and boy did it use some oil hahah, filled the 2 litre catch can in about 10 min thrashing. all the compression is just blowing past the rings into the sump and causing a pressure area and therefore pushing the oil out the only way it can, through the breathers.

leakdown test time i think

the joys of imports hey

Brad

[RT33]

what do they do exactly in a leak down test??? i know its ment to be more accurate than a compression test (i know what that involves)but what do they actually do??? and how much would it cost?

if the rings are stuffed...should i rebuild the block?

can anyone recomend a brand of forged poistons??? should i use gtr rods? what turbo is recomended for great power thats not too laggy???

[Abo Bob]

what do they do exactly in  a leak down test??? i know its ment to be more accurate than a compression test (i know what that involves)but what do they actually do??? and how much would it cost?

if the rings are stuffed...should i rebuild the block?

can anyone recomend a brand of forged poistons??? should i use gtr rods? what turbo is recomended for great power thats not too laggy???

<{POST_SNAPBACK}>

Apart from telling you that all the info you seek is already on this great website I have the following info.

Leak down test. Remove spark plug and force some air from an air compressor in there measuring with a guage what leaks down, ie what gets pushed past the rings and valves.

cost dunno - allow an hour at least on an rb25

yes rebuild the bottom end if they are stuffed.

plenty of recommendations on here about pistons, some dissagreement too

What is great power? what is not too laggy? GT-RS might be the go.