A few oil related problems (Tapping)

[1988SupraDreams]

Hello all, I'm looking for some advice on a few things, but first a background on my car: 1988 NA/AT converted to Turbo 5SPD using a JDM 1990 7MGTE and JDM 1991 R154, with a remanufactured 1991 7MGTE/AT ECU and NEW wire harness. I have been running 4 quarts of Mobil 1 10-30 (Group 4) and 2 quarts of Valvoline Max Life Full Synthetic 10-30 (Group 3 High Mileage) for 5,000 miles now, and am going to drain a quart of oil and add a fresh quart of the Group 3 High Mileage oil to go till 10,000. I have been using my A/T cooler section of my radiator as my oil cooler, but have not seen any problems with doing this yet. Got a new HG as well about 10,000 miles ago, but was installed by a VERY competent Supra owner.

Well, after retightening my turbo elbow bolts for a second time and installing heavy duty lock washers to prevent the problem, I notice a slight tapping noise from under the hood. First thought: Please God don't let it be rod knock. I am running 7PSI through an NA exhaust (Had to shim the wastegate to achieve this through that pea shooter exhaust), and I have been losing oil. The engine looks spotless, but the transmission is completely drenched in motor oil, not transmission oil. The inside of the bellhousing is drenched in oil as well, but the flywheel is also spotless. It makes this noise under any and all conditions, Cold Idle, Hot Idle, WOT, Cruising.

The rear main seal is brand new, I did a wet install, and used the old seal and a rubber mallet to get the new one into place. I know I have a boost leak, but am having one hell of a time finding it. I'm going to be taking off all of the pipes and doing a complete teardown of anything and everything that doesn't have a gasket to see what the hell is going on with my engine.

So here's my oil pressure situation according to the gauge:
Oil pressure at first start up takes about 6-7 seconds to register only when cold.
Oil pressure at cold idle is about 35PSI.
Oil pressure at 2k RPM cold is 40PSI.
Oil pressure under normal cruising condition is about 25PSI.
Oil pressure at hot idle is about 10PSI
Oil pressure at WOT is 37-38PSI.

The turbo has little shaft play and next to no radial shaft play, and boosts fine. I have no engine codes, and no loss of power. I realize that the gauge isint the most accurate gauge in the world, but it does seem a bit low for 10-30 doesn't it?

Sorry for the long post, but I want to give as much information as possible. Let me know if you need more. Any and all help is appreciated. Thank you.

Shawn

 

[mkIIIman089]

Who told you Mobil 1 was a group IV?

Without actual temps its difficult to say whether your oil pressure is acceptable. Also, oil pressure is not based on power percentage, it's RPM only, so "cruising conditions" and "WOT" are pretty much useless. It could have been any RPM when you looked at the gauge...

Plus, counting on the stock gauge to tell you anything is pointless.

If the stock gauge is showing around about 40 when driving at full temp, you're probably OK.

 

[1988SupraDreams]

Who told you Mobil 1 was a group IV?

Without actual temps its difficult to say whether your oil pressure is acceptable. Also, oil pressure is not based on power percentage, it's RPM only, so "cruising conditions" and "WOT" are pretty much useless. It could have been any RPM when you looked at the gauge...

Plus, counting on the stock gauge to tell you anything is pointless.

If the stock gauge is showing around about 40 when driving at full temp, you're probably OK.

Mobil 1 won't say, but it used to be. The Full Synthetic is supposed to be, but not the EP and the Clean lines. Who knows if it is now. The engine has a new stock radiator as well. So my oil pressure seems fine, but I still don't understand what the deal is with the tapping and the oil loss.

 

[quake]

Hello all, I'm looking for some advice on a few things, but first a background on my car: 1988 NA/AT converted to Turbo 5SPD using a JDM 1990 7MGTE and JDM 1991 R154, with a remanufactured 1991 7MGTE/AT ECU and NEW wire harness. I have been running 4 quarts of Mobil 1 10-30 (Group 4) and 2 quarts of Valvoline Max Life Full Synthetic 10-30 (Group 3 High Mileage) for 5,000 miles now, and am going to drain a quart of oil and add a fresh quart of the Group 3 High Mileage oil to go till 10,000. I have been using my A/T cooler section of my radiator as my oil cooler, but have not seen any problems with doing this yet. Got a new HG as well about 10,000 miles ago, but was installed by a VERY competent Supra owner.

Well, after retightening my turbo elbow bolts for a second time and installing heavy duty lock washers to prevent the problem, I notice a slight tapping noise from under the hood. First thought: Please God don't let it be rod knock. I am running 7PSI through an NA exhaust (Had to shim the wastegate to achieve this through that pea shooter exhaust), and I have been losing oil. The engine looks spotless, but the transmission is completely drenched in motor oil, not transmission oil. The inside of the bellhousing is drenched in oil as well, but the flywheel is also spotless. It makes this noise under any and all conditions, Cold Idle, Hot Idle, WOT, Cruising.

The rear main seal is brand new, I did a wet install, and used the old seal and a rubber mallet to get the new one into place. I know I have a boost leak, but am having one hell of a time finding it. I'm going to be taking off all of the pipes and doing a complete teardown of anything and everything that doesn't have a gasket to see what the hell is going on with my engine.

So here's my oil pressure situation according to the gauge:
Oil pressure at first start up takes about 6-7 seconds to register only when cold.
Oil pressure at cold idle is about 35PSI.
Oil pressure at 2k RPM cold is 40PSI.
Oil pressure under normal cruising condition is about 25PSI.
Oil pressure at hot idle is about 10PSI
Oil pressure at WOT is 37-38PSI.

The turbo has little shaft play and next to no radial shaft play, and boosts fine. I have no engine codes, and no loss of power. I realize that the gauge isint the most accurate gauge in the world, but it does seem a bit low for 10-30 doesn't it?

Sorry for the long post, but I want to give as much information as possible. Let me know if you need more. Any and all help is appreciated. Thank you.

Shawn

lifters ticking??? and fix your leaks!

 

[tte]

I see you got your car back on the road aye?

Cheers,
Roy

Hello all, I'm looking for some advice on a few things, but first a background on my car: 1988 NA/AT converted to Turbo 5SPD using a JDM 1990 7MGTE and JDM 1991 R154, with a remanufactured 1991 7MGTE/AT ECU and NEW wire harness. I have been running 4 quarts of Mobil 1 10-30 (Group 4) and 2 quarts of Valvoline Max Life Full Synthetic 10-30 (Group 3 High Mileage) for 5,000 miles now, and am going to drain a quart of oil and add a fresh quart of the Group 3 High Mileage oil to go till 10,000. I have been using my A/T cooler section of my radiator as my oil cooler, but have not seen any problems with doing this yet. Got a new HG as well about 10,000 miles ago, but was installed by a VERY competent Supra owner.

Well, after retightening my turbo elbow bolts for a second time and installing heavy duty lock washers to prevent the problem, I notice a slight tapping noise from under the hood. First thought: Please God don't let it be rod knock. I am running 7PSI through an NA exhaust (Had to shim the wastegate to achieve this through that pea shooter exhaust), and I have been losing oil. The engine looks spotless, but the transmission is completely drenched in motor oil, not transmission oil. The inside of the bellhousing is drenched in oil as well, but the flywheel is also spotless. It makes this noise under any and all conditions, Cold Idle, Hot Idle, WOT, Cruising.

The rear main seal is brand new, I did a wet install, and used the old seal and a rubber mallet to get the new one into place. I know I have a boost leak, but am having one hell of a time finding it. I'm going to be taking off all of the pipes and doing a complete teardown of anything and everything that doesn't have a gasket to see what the hell is going on with my engine.

So here's my oil pressure situation according to the gauge:
Oil pressure at first start up takes about 6-7 seconds to register only when cold.
Oil pressure at cold idle is about 35PSI.
Oil pressure at 2k RPM cold is 40PSI.
Oil pressure under normal cruising condition is about 25PSI.
Oil pressure at hot idle is about 10PSI
Oil pressure at WOT is 37-38PSI.

The turbo has little shaft play and next to no radial shaft play, and boosts fine. I have no engine codes, and no loss of power. I realize that the gauge isint the most accurate gauge in the world, but it does seem a bit low for 10-30 doesn't it?

Sorry for the long post, but I want to give as much information as possible. Let me know if you need more. Any and all help is appreciated. Thank you.

Shawn

 

[1988SupraDreams]

lifters ticking??? and fix your leaks!

The lifters had crossed my mind, but I'm looking for advice on the leaks and reccomended methods to figure out what the tapping IS. The oil pan gasket is new and is spotless, the valve cover gasket is new and is spotless... ALL the gaskets are new. And all the gaskets that I can see with the engine fully assembled are not leaking. I just don't want to believe that it can be a rear main, I am looking for other ideas before I go ripping out my transmission.

I see you got your car back on the road aye?

Cheers,
Roy

Been on the road again for about 6 months now

 

[tte]

How much oil? Alot?

cheers,
Roy

 

[1988SupraDreams]

How much oil? Alot?

cheers,
Roy

Enough so that the transmission always has fresh oil on it, I lost about three quarts on a 130 mile trip. (Which is when I first noticed it at the end of the trip.) It had never done it to this extent before, I might have lost a half a quart of oil after doing that trip twice.

 

[johnathan1]

lifters ticking??? and fix your leaks!

Whoa...and you are supposed to be a certified toyota tech??

Does the tapping sound get louder as you build boost? My car did this, and it turned out to be a pre-turbo exhaust leak...two of the four nuts that hold the turbo to the manifold had completely fallen off (old hardware) and it started out as a tapping that got louder as I would build boost, but gradually turned into a howling sound as the leak got bigger... Also check your exhaust manifold gasket where it mates to the head, and check for stripped manifold studs.

And for the oil leak...my first instinct would be valve cover gaskets...they love to leak at the rear for some reason, and it's even more likely if you didn't use silicone on the seals, and didn't torque the VC bolts evenly...

 

[IJ.]

Enough so that the transmission always has fresh oil on it, I lost about three quarts on a 130 mile trip. (Which is when I first noticed it at the end of the trip.) It had never done it to this extent before, I might have lost a half a quart of oil after doing that trip twice.

If this is true the motor is toast

 

[1988SupraDreams]

Whoa...and you are supposed to be a certified toyota tech??

Does the tapping sound get louder as you build boost? My did this, and it turned out to be a pre-turbo exhaust leak...thwo of the four nuts that hold the turbo to the manifold had completely fallen off (old hardware) and it started out as a tapping that got louder as I would build boost, but gradually turned into a howling sound as the leak got bigger... Also check your exhaust manifold gasket where it mates to the head, and check for stripped manifold studs.

And for the oil leak...my first instinct would be valve cover gaskets...they love to leak at the rear for some reason, and it's even more likely if you didn't use silicone on the seals, and didn't torque the VC bolts evenly...

Trust me, valve covers arent leaking. I already fixed the exhaust leak, AND I used that rinky-dink Aaron Driftmotion Helicoil kit (With slight modifications for efficiency). And no the tapping noise doesn't get louder under boost, I know exactly what sound you're talking about, I used to run Open Downpipe, and it's not that. The sound only occurs when I am increasing RPM's. When I hold the the RPMs steady at any given RPM it doesn't make the noise. It's worst when I first start the engine, and it's just as bad hot or cold.

If this is true the motor is toast

It is...

What's the likely cause?

 

[jetjock]

Ian, that's exactly what I was thinking. It's possible when the three quarts were lost pressure was lost at some point for a brief time. If so that may be what's come back to haunt him. I'd still ID it though. The oil pressure seems fine. I get the same readings and I have what must be the world's mot accurate stock gage. The leak can be found with tracer dye. Sounds like a bungled rear seal install to me.

 

[IJ.]

Dreams: If it was 2>3 qt's low good chance you've lost the Oil Wedge at some point allowing the Crank to touch a bearing which is the start of Rod Knock

JJ: Yep Personally I wouldn't even bother with an Oil Test at this point, I lost a motor that was only 1 qt down on an interstate trip many years ago.

 

[1988SupraDreams]

Ian, that's exactly what I was thinking. It's possible when the three quarts were lost pressure was lost at some point for a brief time. If so that may be what's come back to haunt him. I'd still ID though. The oil pressure is fine. I get the same readings and I have what must be the world's mot accurate stock gage. The leak can be found with tracer dye. Sounds like a bungled rear seal install to me.

So low oil from my crappy rear main seal install caused low oil pressure and... knock?

Dreams: If it was 2>3 qt's low good chance you've lost the Oil Wedge at some point allowing the Crank to touch a bearing which is the start of Rod Knock

JJ: Yep Personally I wouldn't even bother with an Oil Test at this point, I lost a motor that was only 1 qt down on an interstate trip many years ago.

No easy fix. *Sigh*

Time to get me a 4x4 22RE... Would serve me better where I live..

Not gonna ditch the Supra though... yet.

And to whom it may concern: you were right.

 

[jetjock]

IJ: Yeah, plus his oil temp at that level would've driven viscosity. Doesn't sound good. There may be some hope though. I know of a GTE that was driven on the highway without oil until it seized. It went another 40K miles after that with nothing more than a slight ticking in the valve train. It's one reason I'm sometimes amused by all this rod knock stuff

 

[1988SupraDreams]

IJ: Yeah, plus his oil temp at that level would've driven viscosity. Doesn't sound good. There may be some hope though. I know of a GTE that was driven on the highway without oil until it seized. It went another 40K miles after that with nothing more than a slight ticking in the valve train. It's one reason I'm sometimes amused by all this rod knock stuff

So what can I do to make this motor have a slight ticking in the valve train?

 

[IJ.]

So what can I do to make this motor have a slight ticking in the valve train?

Start off with a fresh rebuild

It could very well be another issue but going on the facts presented my guess would be it's wiped a bearing.

 

[1988SupraDreams]

Start off with a fresh rebuild

It could very well be another issue but going on the facts presented my guess would be it's wiped a bearing.

Pull the motor and change the bearings you mean?

 

[tte]

Pull the motor and change the bearings you mean?

Yeah...also get everything else checked.

I thought you took your block down to Rob's to get it machined already or did you just get a jdm?

Cheers,
Roy

 

[IJ.]

Go through a bunch of the basics first before pulling the motor...

Unclip an injector at a time and see if it stops.

Try using a long screwdriver as a stethoscope and listen around the motor.

Has the Oil Pressure dropped since it started tapping?