FA20 Engine Oiling, Bearings, and Starvation

[solidsnake11]

So I have been studying the oiling system of the FA20. Here is my assumption of major problems which I have attempted to fix in my build.

First thing I noticed is the oil pick up, only engine I have found with the screen at top of oil level and its very tiny. Nice small vacuum cleaner nozzle to suck up any debris and stick (block) the tiny taxed screen.My pump showed signs of cavitation, looks like an object that has been sand blasted. Cavitation is caused from to restrictive intake of a liquid pump. I have plans to make an old school pickup with a larger screen on bottom.

Next what in the world is the tempature sensor stuck in the worse possible place right in a Z bend that blocks the main feed to the main rod bearings in the front cover. I ported and took the Z out.


Next where the front cover feeds the block its less than 25/64 drilled mine to 29/64 at feed and straight down the oil gallerie from top. Drilled oil pump cover 29/64 to match. Also plugged the oil gallery that leads to nowhere eliminating an Oring between case halves.

ok next thing drivers head feeds straight off the main feed guess where, right before the z with the temperature sensor stuck in it. for some reason they decided to make it much larger than the feed to the passenger head. Plugged with a restrictor to match passenger heads smallest restriction which is in front cover. Only other thing this side feeds is one of the tensioners which has a 1/32 oil hole in it. Bought my BRZ with oil starved spun bearings, heads seem to have run on low oil fine.

Other modifications to oiling, smoothed passages out in front cover. Oil pump epoxied small bypass hole up, cut the walls on an angle so front cover would have a mechanical stop on the plug, I can weld aluminum but I didn't want to warp the oil pump cover. Shimmed oil relief valve with 5 number 10 washers. Used Gasgacinch on pump and oil gallery plates. Update don't use Gasgacinch use Loctite 518 or equivant

Fixes with out taking engine apart, relocate the oil temperature sensor( I would probably put it in the oil pan). If sensor is relocated find a fitting to fit the temperature sensor hole and run a external line to the plug to oil galleries on top of block where all the turbo guys run there feeds from, this will bypass the Z. Please make sure to use high quality lines and check them often.

Other things that could be done for race engines, drill extra feed to center main on opposite side of oil galleries through to case bolt bore , drill from top of block to bolt bore and run external line to cover before Z, bolt will seal the bore.

If any you guys have oil pressure gauges take the temperature sensor out and plug hole and see if you get extra pressure. Let us know.


Turbo guys relocate the turbo feed from top of block your taking oil away from your rods, tee from oil pressure fitting make sure it doesn't protrude in the block any further than the stock oil pressure sensor

Pull pan off and check, clean pick up tube.

Most mods was done to the front cover so engine does not have to come out for the majority.

Thanks,
Scott

[solidsnake11]

[Milhouse86]

Long thread but a good read

[Series.Gray86]

Originally Posted by solidsnake11

So I have been studying the oiling system of the FA20. Here is my assumption of major problems which I have attempted to fix in my build.

First thing I noticed is the oil pick up, only engine I have found with the screen at top of oil level and its very tiny. Nice small vacuum cleaner nozzle to suck up any debris and stick (block) the tiny taxed screen.My pump showed signs of cavitation, looks like an object that has been sand blasted. Cavitation is caused from to restrictive intake of a liquid pump. I have plans to make an old school pickup with a larger screen on bottom.

Next what in the world is the tempature sensor stuck in the worse possible place right in a Z bend that blocks the main feed to the main rod bearings in the front cover. I ported and took the Z out.


Next where the front cover feeds the block its less than 25/64 drilled mine to 29/64 at feed and straight down the oil gallerie from top. Drilled oil pump cover 29/64 to match. Also plugged the oil gallery that leads to nowhere eliminating an Oring between case halves.

ok next thing drivers head feeds straight off the main feed guess where, right before the z with the temperature sensor stuck in it. for some reason they decided to make it much larger than the feed to the passenger head. Plugged with a restrictor to match passenger heads smallest restriction which is in front cover. Only other thing this side feeds is one of the tensioners which has a 1/32 oil hole in it. Bought my BRZ with oil starved spun bearings, heads seem to have run on low oil fine.

Other modifications to oiling, smoothed passages out in front cover. Oil pump epoxied small bypass hole up, cut the walls on an angle so front cover would have a mechanical stop on the plug, I can weld aluminum but I didn't want to warp the oil pump cover. Shimmed oil relief valve with 5 number 10 washers. Used Gasgacinch on pump and oil gallery plates. Update don't use Gasgacinch use Loctite 518 or equivant

Fixes with out taking engine apart, relocate the oil temperature sensor( I would probably put it in the oil pan). If sensor is relocated find a fitting to fit the temperature sensor hole and run a external line to the plug to oil galleries on top of block where all the turbo guys run there feeds from, this will bypass the Z. Please make sure to use high quality lines and check them often.

Other things that could be done for race engines, drill extra feed to center main on opposite side of oil galleries through to case bolt bore , drill from top of block to bolt bore and run external line to cover before Z, bolt will seal the bore.

If any you guys have oil pressure gauges take the temperature sensor out and plug hole and see if you get extra pressure. Let us know.


Turbo guys relocate the turbo feed from top of block your taking oil away from your rods, tee from oil pressure fitting make sure it doesn't protrude in the block any further than the stock oil pressure sensor

Pull pan off and check, clean pick up tube.

Most mods was done to the front cover so engine does not have to come out for the majority.

Thanks,
Scott

Any update on the effectiveness of these modifications?

[NoHaveMSG]

Originally Posted by Series.Gray86

Any update on the effectiveness of these modifications?

We won't reply. He got upset in some other threads and deleted most of his posts and left the forum years ago. Shame as he had lots of good info. Surprised he didn't delete his posts in this thread like he did his others.

[Eaton PSI]

Are we allowed to post ebay links in here?
I just ordered an oil pump upgrade kit. It comes with a set of 14mm FA20F gears and a special stepped back plate that fits directly to the BRZ timing cover. I will be using it on my next build.
Also, people have been talking about the hole in the rocker pivots. If you have a close look at the heads, you'll see the oil doesn't come through the pivot. Inlet side has a row of holes with tiny roll pin restrictors fitted, exhaust side has notches cut in the sides of the pivot bores. There is no path for oil to come out of the hole in the pivots. The early pivots with the bigger hole have a different profile which allows a few more degrees of rocker motion (capable of more valve lift).
The heads also have brass restrictor plugs in the oil galleries. The cam phasers get a LOT of oil, but the rest of the head is fed through tiny holes.

[demasrv]

Originally Posted by Eaton PSI

Are we allowed to post ebay links in here?
I just ordered an oil pump upgrade kit. It comes with a set of 14mm FA20F gears and a special stepped back plate that fits directly to the BRZ timing cover. I will be using it on my next build.
Also, people have been talking about the hole in the rocker pivots. If you have a close look at the heads, you'll see the oil doesn't come through the pivot. Inlet side has a row of holes with tiny roll pin restrictors fitted, exhaust side has notches cut in the sides of the pivot bores. There is no path for oil to come out of the hole in the pivots. The early pivots with the bigger hole have a different profile which allows a few more degrees of rocker motion (capable of more valve lift).
The heads also have brass restrictor plugs in the oil galleries. The cam phasers get a LOT of oil, but the rest of the head is fed through tiny holes.

Honestly, I don't know that the pump is the problem. At higher RPMs it's moving a LOT of oil. From my experience, the heads receive enough oil. Problem seems to be that the bearings don't.

[blsfrs]

While we are on the oiling subject: Has anyone done anything to their OEM oil temperature sensor to make it less intrusive?

[NoHaveMSG]

Originally Posted by Eaton PSI

Are we allowed to post ebay links in here?
I just ordered an oil pump upgrade kit. It comes with a set of 14mm FA20F gears and a special stepped back plate that fits directly to the BRZ timing cover. I will be using it on my next build.
Also, people have been talking about the hole in the rocker pivots. If you have a close look at the heads, you'll see the oil doesn't come through the pivot. Inlet side has a row of holes with tiny roll pin restrictors fitted, exhaust side has notches cut in the sides of the pivot bores. There is no path for oil to come out of the hole in the pivots. The early pivots with the bigger hole have a different profile which allows a few more degrees of rocker motion (capable of more valve lift).
The heads also have brass restrictor plugs in the oil galleries. The cam phasers get a LOT of oil, but the rest of the head is fed through tiny holes.

Killer B Motorsports has some posts about it and the stock pump is fine. More than adequate flow.

The stock pivots on the early cars are only different on one side. When they changed the valve stem lengths and pivots they just made all the pivots with the holes the same size. I am also pretty sure oil does come through the pivot holes, that galley is pressurized, I lost pretty much all oil pressure when one of my engines kicked two rocker arms and there companion rocker pivots.

[Eaton PSI]

Yes, a lot of oil will flow out of the gallery if the rocker pivot falls out. When the rocker pivot is in place, no oil comes out of the hole. Grab a head and have a close look.

I'm about to start assembling my engine. Oil pump is done, big gears and ported passages in timing cover.
I am having trouble getting correct main bearing clearance. Crank is on top size, tunnel is on bottom size but I've got 0.003" clearance. I have ordered 2 sets of different brand bearings, 1 which is 0.001" undersize. Service manual specs 0.0005-0.0015" clearance.
This engine had previously spun a rod bearing at 70,000km. I wonder how many engines that spun bearings had issues with excessive bearing clearance from factory.

[NoHaveMSG]

Originally Posted by Eaton PSI

Yes, a lot of oil will flow out of the gallery if the rocker pivot falls out. When the rocker pivot is in place, no oil comes out of the hole. Grab a head and have a close look.

I'm about to start assembling my engine. Oil pump is done, big gears and ported passages in timing cover.
I am having trouble getting correct main bearing clearance. Crank is on top size, tunnel is on bottom size but I've got 0.003" clearance. I have ordered 2 sets of different brand bearings, 1 which is 0.001" undersize. Service manual specs 0.0005-0.0015" clearance.
This engine had previously spun a rod bearing at 70,000km. I wonder how many engines that spun bearings had issues with excessive bearing clearance from factory.

I have an engine behind me. The oil galley is round. The bottom of the pivot is flat and the hole goes all the way through. Oil passes through. This was 7 3/4” zip tie.

https://youtube.com/shorts/Y6Bw_reu4...Xj8ggv-NfQc4sE

[Eaton PSI]

First pic shows the inside of the pivot hole in the head. The pivot completely blocks the gallery. There is no hole in the side of the pivot to allow oil through.
The little black circle next to the pivot hole is a small roll pin which acts as a metering jet to spray a small amount of oil at the cam.
Second pic show the brass oil restrictor plug in the galleries directly behind the cam phasers. I couldn't get a good shot with the camera, but the hole is probably less than 1mm. Max flow to phasers, restricted oil to the rest of the heads.

[NoHaveMSG]

Originally Posted by Eaton PSI

First pic shows the inside of the pivot hole in the head. The pivot completely blocks the gallery. There is no hole in the side of the pivot to allow oil through.
The little black circle next to the pivot hole is a small roll pin which acts as a metering jet to spray a small amount of oil at the cam.
Second pic show the brass oil restrictor plug in the galleries directly behind the cam phasers. I couldn't get a good shot with the camera, but the hole is probably less than 1mm. Max flow to phasers, restricted oil to the rest of the heads.

I guess I didn’t look that closely at the passage. It does still feed though. I pulled a rocker off and sprayed brake clean into the tip of the pivot and it runs out the galley.

[Eaton PSI]

Stock timing cover/pump plate, modified to fit WRX 14mm gears. 15% more pump volume. A very tricky bit of machining!
My daily driver has about 10psi pressure at idle with 0w20 oil @95degC. Changing to 5w30 upped it to about 12psi, temps didn't change enough to notice. Bigger pump should get it up to about 14psi, although the new engine will have big end clearance on the larger side so I'll have to wait and see...