Oil Advice for 4AGTE help please

[Sparky_2day]

Hi,

Im after some advice from anyone with experience from running a 4agte setup or anyone with high spec 4ag engines.

i finished building my engine about this time last year run it in on mineral oil and then before having a very basic road map changed to 15w 50 mobil 1 fully sythyetic oil.

Due to a bad year last year, my car spent most of its time off the road as i couldnt drive it and i only managed to do about 2000 miles or so. everytime ive driven the car ive been able to smell oil and lost a little, always leaving a tiny puddle where ever i parked. ive found that it is leaking from my cam sensor (Running a distributorless ignition 4agze block). ive changed this o ring 3 times for the genuine toyota one and everytime the engine warms up, the increase of oil pressure from reving the engine up just makes oil constantly drip out like a tap.

i dont understand why as i thought the head was not under any pressure unyet the oil bypasses the o ring asif it wasnt even there. Iam wondering if the oil is far too thin? a source at the time said i 'should be fine ' on mobile 1 and i wanted to use it for its high temperature tolerance etc.

im really eger to get my car mapped to its full potential of around a bar of boost pressure from an HKS roller bearing GT28 turbo, ive just got to get this sorted first and its abit embarrising as ive built the engine myself and then one o ring seems to be letting me down.

Has anyone had oil leaking from the distributor before?
whats the best way of sorting it?
What grade Fully sythetic are people using?

If anyone can help it would be greatly appreciated.

Thanks,

Rob

[scomr2]

This sounds most like there is a problem with the cam sensor - maybe the O ring groove in the sensor doesn't match the one in the dizzy so the stock O ring isn't sealing properly.

O rings are sized by bore and ring x-section - you could try a thicker x-section to see if that helps.

[PW@Woodsport]

I'd guess your cam breather/catch can setup isn't dealing with the blowby efficiently enough.

Try increasing the bore of the cam cover outlet, maybe put another on the front cover if you haven't already, and increase the breather pipe diameter.

That should drop the pressure (not the oil pressure) inside the engine, which i suspect is what is forcing oil out.

[PW@Woodsport]

bloody hell the spammers are getting all techy!!

EDIT: spam deleted.

[Sparky_2day]

Thanks for the quick reply,

didnt think about adding a breather tap off to the exhaust cam cover, will try that i think. ive always wondered why the 4age dosnt have one on each like alot of engines and it does seem to breath quite heavy.

if that fails ill look for a thicker o ring, just seems odd that the correct one would be too thin. Thanks for the advice.

out of curiosity are there many people using mobile one in a 4ag engine?

[scomr2]

Even if it's a heavy breather the O ring should still seal realiably. A properly fitted O ring deforms under the applied pressure to create a seal - up to the limit the more pressure that is applied the better the seal gets!

15W-50 isn't particularly thin oil either - racers use 0W-30 to release more power.

[Lauren]

It's not your oil, it's getting the correct O ring. I had a late 4AGZE engine (AE92) and it never leaked there, so maybe it's a case of getting the correct O ring.

It'll be simpler to do that rather than fit extra breathers and if you do it'll doubtless continue to leak anyway. Sort the problem I think.

[rikster]

valvoline 5w-40 is good oil or castrol edge sport 10w-60

[Sparky_2day]

Hi again,

Thanks for all the replies,

happy with the oil choice now, thanks for resting my mind on that.

I fired the car up this morning, first chance ive had in a while, i left the toyota o-ring in and warmed it up without the oil cap on. i thought this would make a huge temporary breather, and no leak at all. put on the cap and leak starts straight away.

Cam covers are now comming off and huge breathers gonna get welded on hopfully in the week. i think changing the o ring would not be stopping the cause of the issue only keep the pressure in the head sky high.

Thanks again for everyones input, cheers paul for mentioning the breathing system spot on as always.

Rob

[MartG]

Check that the standard breather isn't blocked before you do anything else