18RG oil drain?

**Celica RA45** · 10-01-2006, 03:31 PM

its only 2tg, 18rg even the 3k motors as well they all have to much oil up top, hence thats why we put restricters in the oil line feeding the head

**SeptemberSquall** · 10-01-2006, 03:35 PM

Originally Posted by Celica RA45

its only 2tg, 18rg even the 3k motors as well they all have to much oil up top, hence thats why we put restricters in the oil line feeding the head

did you have problems with too much supply for the drains or just too much pressure?
what was the problem with the pressure, apart from popping the welch plugs?

**rolleraction** · 10-01-2006, 03:37 PM

Yes Karl, restricting the flow to the head using restrictors with around 2mm holes is common as Glenn says, the head doesn't need too much oil. Better to leave the oil in the sump rather than pump it all into the head and risk starvation in the sump. I am speaking in terms of wet sumped high RPM race engines tho...

Later model Toyota head gaskets have 'reducers' in the gasket itself that result in about a5 to 6mm oil gallery having to pass through a 2-3mm hole in the head gasket before going into the oil gallery in the head... same result (probably better as easier to flush out a larger oil gallery when rebuilding, than a gallery with a reducer pressed into it)..

Cheers

Steve

**The Witzl** · 10-01-2006, 05:34 PM

Steve and Glenn,

thanks a million for that! I guess that this excessive oil in the heads, combined with/atributed to the relatively poor oil drainage in those heads is what leads to the ever so common oil starvation that 2TGs and 18RGs experience??

This information is of great use to me, as I'm building a (hopefully) relatively respectable turbo 18RG which will possibly see 8000rpm, so oil flow volume and oil return drainage to the sump are obviously important factors to consider!

Out of interest, did you ever improve the baffling in the sump, or do anything else to ensure a reliable oil supply to the engine?

**Celica RA45** · 10-01-2006, 05:49 PM

you can baffle the shit out of it, BUT the weak link is the shit rods and rod bolts ,hence thats why most are dry sumped,with forged rods and pistons . the early 1s had to run wet sumps so you could use a accumultor ,which is a mini oil reserve that holds 2 liters of oil under pressure and when you loose pressure its shoots the 2 liters to the engine saving it from going BOOM

**SeptemberSquall** · 10-01-2006, 06:02 PM

Originally Posted by Celica RA45

you can baffle the shit out of it, BUT the weak link is the shit rods and rod bolts ,hence thats why most are dry sumped,with forged rods and pistons . the early 1s had to run wet sumps so you could use a accumultor ,which is a mini oil reserve that holds 2 liters of oil under pressure and when you loose pressure its shoots the 2 liters to the engine saving it from going BOOM

Larger sump would probably help, mine is approx 7lts. total.

**The Witzl** · 11-01-2006, 05:05 PM

so will i have much problem with aftermarket Crower Rods and extra sump baffling?

What else would you recommend i do to the engine to ensure an uninterrupted supply of pressurised oil? I just really REALLY dont want the engine to go bang

**-GT-** · 11-01-2006, 05:36 PM

I have a feeling something done to my engine before i got it may be for the same sort of reason, but maybe a different approach to the solution?

I've got an AE101 20V, and i got it off a guy who uses them in his Westfield race car. He said that they had some problems with oil buildup in the head, due to the transverse engine being used (read: raced) longitudinally and the oil pooling up the back of the head under prolonged acceleration.

He drills out the welsh plug there above the thermostat and taps a fitting to run a return feed straight into the sump. It's not a small line either, 5/8 or so, he ground a bit off the top of the thermostat housing for clearance. I don't run the line, being in an AE93 i see it as being used just the way it was designed to be, so have just capped both teh fittings.

If the problem was too much supply for the drains something like this would work just as well, is it a matter of reducing flow/pressure to the head, or more preventing buildup?

**rolleraction** · 11-01-2006, 05:38 PM

Yep Larger capacity sump is a good thing. Starvation usually occurs during longer duration fast sweeping corners (a-la race track) more so than on the street so you should be ok by increasing sump capacity and baffling.

As Glenn says, an accusump or similar is also good insurance

http://www.accusump.com/acc_tech_diagrams.html