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Madd Tyte JDM yo ®
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7,014 Posts
Discussion Starter #1 (Edited)
Greetings everyone, Today i would like to share with you some experiments i performed on a friends supra. his car was down with rod knock so we had to tear out his motor to replace all the lower end bearings. i figured we could use his car as a guinea pig. he was up for it, so we proceeded to fix the bearings and rebuild the bottom end and then address the oiling issues before wrapping it all up.

you will see various pictures of how i decided to go about solving the inherent problems that the 7MGTE oiling system has. So far, we have identified FOUR problems with it to date;

1. Releif valve spring set to release at 40psi
2. Oil pump Pickup is 1 3/8" from floor of oil pan
3. Oil pump discharge line is fastened with a banjo bolt
4. Oil filter mount has 2nd integrated releif spring that bleeds off approximately 1/3 oil pressure/volume to the oil cooler and returned to the pan.
(#4 Fixed in this thread: http://www.supraforums.com/forum/showthread.php?t=371814)

In this thread, i will describe and show you how i addressed the first 3 problems. solving the 4th problem had to be put off for a later date as we were on a strict budget and was something that didnt require engine removal to perform.

1. Releif valve spring set ot release at 40psi.
Im sure you all are familiar with shimming the oil pump releif spring. the spring is held in the oil pump body with a large bolt that is hollow inside which seats the end of the spring. Its the large silver bolt with the small discharge orifice in the head of it.


remove this bolt and the spring will pop out. turn the bolt over and you will see that it is hollowed out inside so that the spring may be seated inside of it. you need to find some washers that will fit inside this hollowed out bolt, and allow oil to pass thru them and out the small orifice so that the releif valve will still function. you want to create a stack of washers that is approximately 10mm-12mm tall. any fewer than this, and there wont be much of an increase in oil pressure to speak of. on this particular application, we did two washers, which was ~3mm. the oil pressure did not increase much over stock to cause celebration. Live and learn. reinstalling the bolt is difficult, as it will require the spring to be compressed moreso than it was when removed... having a C-clamp or even a second hand available to hold the spring/bolt against the oil pump as you turn the wrench will save you many headaches. unfortunately, i was unable to get more pics of this during the procedure. i didnt stress it as this is the most common and intuitive of the oil pump mods.

2. Oil pump pickup being too far from the oil pan floor.
We have discussed this on occasion as well. when rebuilding the bottom end on this particular car, i decided to find out JUST exactly where the pickup sat. In my experienc with building V8s, i wanted to shoot for ~3/8" or 10mm of clearance between the pickup head and the oil pan, to prevent starvation under any conditions, even low oil level. i used a straight edge and a ruler to measure the distance from the oil pan flange to the floor and then to measure the distance of the pickup head from the oil pan mating surface on the block... the inlet of the pickup was OVER an inch away from the pan. the screen of the pickup is about 1/2" fromt he floor of the pan, but the screen doesn not suck in oil, the inlet of the tube is about 1/2" away from the screen. I rolled the screen flat so it was about 8mm-10mm from the inlet of the tube. this will allow it to sit closer to the pan without interference. then, using a pry bar, i rested it against the releif valve bolt on the pump and pried upward on the oil pump pickup tube. this pulled the pickup away from the block about 12mm. if you refer to the pic below again, you will see that the brace for the pickup head is now hovering above the block. this requires the use of a longer bolt and spacer in order to properly secure the brace.



3.Oil pump discharge line is fastened with a banjo bolt

If you refer to the next pic, you will see the STOCK oil pump discharge line. this is the stock high pressure line that connects the output of the oil pump to the oil feed galley on the block. the banjo bolt fitting and crush washer bolts directly to the side of the oil pump. the BSP-tube nut adaptor end is where it affixes to the block itself, right next to the pickup brace.

These nexts pics will show you more detailed angles of what i had to do to get this to work. as no one has ever done this before ot my knowlege, ill do my best to present it to you so its easy to digest... there could have been someone out there with 1000rwhp 7MGTE that has done this, but ive never seen this done before till i thought it up. somehow, i had to change the entire discharge line to something that would flow better than the stock piece shown above. a theory a friend and i had come up with (Chris90NA-t) was that the banjo fitting was so restrictive that it was creating so much backpressure INSIDE the oil pump that the releif valve was releasing well before the oil pressure inside the oil gallies was ever seeing 40psi. as well all know, oil pressure is NOTHING without oil volume. oil pressure is a function of volume. the banjo fitting used by toyota is not conducive to high volume/flow. first, i didnt want to downsize or upsize the line, i measured it and it was approximately 1/2" ID. Great, so we will use -8AN hose and hose ends. now, how the hell do we convert the metric fittings (Banjo and block thread) to -8AN? well luckily, i have a few hose and fitting shops in town. i took them the banjo bolt and block fitting and told them to find me an adaptor to convert to -8 JIC/AN, 37* flare. the banjo bolt was a 18mm straight thread. the Block fitting is BSP, or very very close to 3/8" NPT pipe thread. the 3/8" NPT and similar BSP are only 1 thread per inch off. since its an interference fit and seals more as you torque it down, this was inconsequential; it was going to seal regardless. we then installed the block adaptor and oil pump adaptor as well as the 90* hose end on the pump.

the oil pump banjo adaptor and 90* AN hose end protruded so far from the pump, i was worried that it would interfere with the oil pan placement. it DOES. dry fitted the oil pan with the pump bolted down in stock form, the hose end does hit the pan. fortunately, the bolt hole in the oil pump flange is large enough to accomodate ~10* of rotation. we rotated it clockwise as far as possible, then locked it down. the oil pan now clears the hose end. however, the pickup brace is now skewed to the side ~10mm.

If you look at this picture again, carefully, you will see that the pickup brace is angled about 7-10* so that it would meet the bolt hole in the block. the brace is pliable enough to where it will bend back into position and allow sufficient boltery. Here is another pic showing that the 90* hose end BARELY clears the oil pan rail on the block.

After installing the oil pump fitting and the block fitting, i then installed a 45* hose end on the block fitting to alleviate some of the curvature required to pitch the oil line over the pickup tube. Here you see both hose ends installed on their respective adaptors as we try to acquire the correct angle for the straightest possible line over the pickup tube.

i then removed the 45* hose end, and installed it onto our 1' length of Braided SS -8 hose. then i reinstalled it onto the block and bent it over the pickup tube at the desired angle in order to get the correct length. i didnt want to cut it too short because i cant put the hsoe back together.

here is a little tip. i used the cutoff wheel for the Dremel tool to quickly cut thru the stainless outer braid, but NOT thru the rubber inner liner. this would have introduced a significant amount of rubber crumbs and dust inside which can get into the oiling system. after cutting the outer braid, i used some scissors or single edge razor to cut thru the neoprene. it works quite well and less of a mess. however, before final assembly, spray it out with brake cleaner and high pressure air to dislodge any debris that may have gotten inside when the line was cut to length at the store. i did one final mockup to make sure that it was the right length and it was... measure twice, cut once, measure again... And, here are some final shots of the oil line after i installed the 90* hose end to mate to the oil pump, also pay attention to the clearance going over the pickup tube. its IMPERATIVE That stainless braided hoses NEVER ride against another metal surface. vibration and movent WILL cause the hose to saw and errode the other surface.



so, after final assembly, the oil pan went on without any issues. the pickup did not bind on the oil pan floor, the discharge tube didnt hit the baffling and the shims stayed in the oil pump. after reassembling the bottom end and putting the motor back together, i put my personal seal of approval on the motor
 

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Madd Tyte JDM yo ®
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7,014 Posts
Discussion Starter #2
Special thanks to Chris90NA-T for brainstorming and IdealSupra for being running 4 qts low on oil, developing rod knock, dragging me into rebuilding the bottom end and being my guinea pig.

as some of you know, Idealsupra/Jayson made the trek from Tampa, Fla to Houston, Tx for the Tx2k5 meet. He made it there and back without a hitch, as well as the long drive to the drag strip. He reports back that the car is alive and well, however we are not seeing as much oil pressure as we had hoped to gain from the releif shimming.. which lead me to up the ante from 3mm shim to 10-12mm shimmery.

hopefully you understood this all and enjoyed reading it as much as i did developing it!
 

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No One Ever Listens To Me
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5,467 Posts
yeah on a sidenote i think once i switch to the 20/50 oil the pressure will be even better....

and maybe one day we can shim it more ;)

and for the record i helped brainstorm too bitch ;)

good writeup though
 

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Madd Tyte JDM yo ®
Joined
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7,014 Posts
Discussion Starter #4
lol.. you were there when i told you the idea... Chris and i came up with this like... last year. i actually sold him a spare oil pump cuz he wanted to do this himself but never got the chance... cuz his bike was stolen then he got in an accident and bad crap keeps happening... so i beat him to it ;)

yeah, we will just jack up your car and pull the oil pan off and shimm it some more... mmkay.

but, i want to see how it turns out with the 20w50... ill be it makes a notable difference with that
 

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greasemonkey
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3,123 Posts
great info, however 1 thing is wrong, the little hole in the bolt for the releif spring isnt the return for the oil, if you look at the bottom of the pump you will see the excess presure is bled off back to the pickup of the pump internally. my hole is blocked and i can tell you for a fact it has made no dramatic increase in pressure. also, i myself plan to make a new pickup entirely of a slightly larger diameter since the stock one is crush bent. and ill port the inlet of the oil pump a bit as well. im guessing you got the fittings at amazon hose right? do you recall the part numbers? ill go pick them up soon so i can check fitment of the 5m front sump pan.
william
 

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Madd Tyte JDM yo ®
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7,014 Posts
Discussion Starter #6
oh, well i figured it bled out externally back into the pan.

then i guess it means you can use solid bar stock to shim the spring rathre than washers. no biggie. i was worried it had to stay open.

and i didnt go to amazon, i got it at Goodyear Hose and Rubber. there are a few of them here in St. Pete.. ALOT easier for me to go there than all the way into tampa, but Amazon would work better for you since itd be less of a drive.

the only thing i got at the Goodyear joint was the banjo adaptor. it was a Parker fitting. i dont have the package here, so i dont remember what the PN is... i remember its an 18mm thread for the banjo, the other is a BSP for sure. if you take the banjo bolt and the block stud to amazon, they can match the threads for you on the spot... thats how i had to do it the first time around.
 

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1JZ BLING!
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2,747 Posts
BTW by comparison the JZ pickup is very very close to the bottom of the pan and very thin to be better submerged in the oil.

A custom pickup would be nice, or add the JZ pickup somehow.
 

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Madd Tyte JDM yo ®
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7,014 Posts
Discussion Starter #9
yeah, a custom pickup would be the hotness... that may be something i attempt in the future... like adapting a JZ pickup or a V8 pickup..

i dont like how the pickup tube is perpendicular to the level of the oil... the pickup surface area is only equivalent to the diameter of the tube... but on V8's, it opens up to a larger chamber that can suck in alot more oil... like this one here.


thats a Big Block chevy pump with pickup made by Moroso. the pickup tube goes in from the side and the entire pickup head is open onthe bottom... its like trying to vaccum your living room with the hose and an extension or the actual sweeper head; which is giong to pick up more stuff?
 

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Captain Hammer
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2,020 Posts
What about cooling your oil if you remove the adapter? Create a new adapter to run a cooler?
 

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Registered
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2,138 Posts
adam what kind of oil pressure are u getting at idle with your setup? Would be be best to shim the oil pump AND ditch he 90 degree filter block for an aftermarket block? Or just simply leave the oil pump alone and go with an aftermarket filter relocation kit to replace the 90 degree block?

I am rebuilding my motor currently so this would be good info to know.
 

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Oldie but a Goodie
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1,465 Posts
My only question is in regards to the brace. Did you use washers or some sort of spacer between it and the block once you tightened it down? just for the sake of security i would think you'd want to bolt that down to something hard, not just have a bolt partially threaded to hold it from moving further fromt he block.
 

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25psi = 14" brakes :)
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2,306 Posts
Just curious if there is a 90 deg. elbow that would work v/s the fitting and then a 90 swivel?

So, you eliminate the distance the 90 sticks out, and you use a straight AN fitting for the hose with your 45 swivel like you have.

Should solve the clearance issue.

This is a mod I'm doing for sure now on my Stroker motor. :)

Already have the pump bypass shimmed about 15mm.
 

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...heading for 500+ RWHP
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467 Posts
Excellent info!! I would like to thank everyone out there who has used their MK3 as a guinea pig for the sake of the community. This info wil make a great starting point for makeing a cure to the 7M oiling system bugs!
 

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No One Ever Listens To Me
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5,467 Posts
adjuster...there really werent any clearence problems with above said fittings...it looks like there might have been but the pan went on with no problems at all.

im going to be putting in 20w50 in about a day and ill post up to see if the results are more noticeable...also an engine myself and chris(flybyux2) just put into his car has this mod with the extra shimming so we will be able to tell if that helped more as well ;)

we are getting there...we CAN fix all the oiling issues with this car...one way or another ;)
 
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