Rattling sound under engine RPM increase, any ideas?

[Dirgle]

dirgle, That's what I suspected, but I don't think that this is as permanent as a typical connecting rod bearing slap. The sound was as quiet as the injectors (about half as loud) and it would only happen under those RPM numbers, never at idle and only then at lower oil pressure read outs in those RPM ranges............

I really hope your right. In my case however, you could barely hear the noise over the injectors when it first started. Even with my *electronic ears you couldn't tell it was rod knock until you put the microphone on the block next to the bearing that had failed. And it would only make this sound between 2400-3600 RPM. You wouldn't hear the sound under load. And you would primary hear it on the acceleration of the engine or if you kept the engine at a constant speed inside the above stated RPM band. But what was weird was that it would only occasionally make the noise on deceleration of the engine. And I wasn't getting as much oil pressure at higher RPM's as I would have liked. So I replaced the oil, and my oil pressure returned to normal, and the noise went away. Only for the noise to return 1500 miles later. At which point I had accepted the fact that I had rod knock. Not bad though for an engine with 187,??? miles on it. Since your a fellow supra brother I'm going to hope you haven’t succumbed to the rod knock, but I still think that’s what it sounds like.

*Electronic ears- a sensitive microphone on the end of a wand, connected to an amplifier and then a set of head phones. Used to listen to internal engine noises. Many people just use a screwdriver with one end against the engine block and one end against their ear. However the set of electronic ears allows you to get to harder to reach places.

 

[MisterTurbineTwister]

Now that I recall, it only did it sometimes and only on acceleration. I guess I will find out.

Ideal, when you said "TOYOTA says 5.5 quarts when doing an oil change with a filter...so maybe you should check THAT out..." What source are you getting this information from? Is it a dealership?

If it is a dealership, I'd like to know why the guy at the dealership would tell you that. Not to doubt what you've heared or anything man, it just doesn't add up to the drain and refill numbers in the TSRM. If you did get those numbers from a dealership, they may have referenced the dry fill numbers from their computer, which is 5.4 US Qts.

A lot of people get dry fill and drain and refill numbers confused and often refer the first number (which is always the dry fill number) when they research fluid capacity in any manor (oil, antifreeze, brake fluid, transmissions or anything that takes fluid). They are not the same at all.

When you refill an engine after oil has already been run in it, oil film covers parts of the engine and stays in some areas like coolers and lines (if applicable) galleys and low areas that do not get drained from the engine at a refill. This all adds up to the amounted difference in refill and dry fill numbers (about half of a quart give or take usually, depending on the engine). Most of the time when you call some place to get capacity numbers, they vary depending on the technicians experience and knowledge and the source that they are reading the numbers from.

The figures that I listed are from the Toyota Supra Factory Repair Manual originally published by the same engineers that designed the 7M-GTE. You don't get any closer to the original source than a factory repair manual for this reason.

The 20W50 oil is suggested to be used in consistantly hotter operation climates according to the TSRM. 15W40 is the base line viscosity weight numbers suggested to use under normal operation by the TSRM.

 

[IJ.]

The TRSM also lists the head bolt torque as 58 ft/lbs.

I'd rather overfill by 1 Qt and NOT lose an engine to rod knock.

I lost one early on rebuilt it and did 100,000 KM's without an issue running it this way.

 

[Idealsupra]

Now that I recall, it only did it sometimes and only on acceleration. I guess I will find out.

Ideal, when you said "TOYOTA says 5.5 quarts when doing an oil change with a filter...so maybe you should check THAT out..." What source are you getting this information from? Is it a dealership?

If it is a dealership, I'd like to know why the guy at the dealership would tell you that. Not to doubt what you've heared or anything man, it just doesn't add up to the drain and refill numbers in the TSRM. If you did get those numbers from a dealership, they may have referenced the dry fill numbers from their computer, which is 5.4 US Qts.

A lot of people get dry fill and drain and refill numbers confused and often refer the first number (which is always the dry fill number) when they research fluid capacity in any manor (oil, antifreeze, brake fluid, transmissions or anything that takes fluid). They are not the same at all.

When you refill an engine after oil has already been run in it, oil film covers parts of the engine and stays in some areas like coolers and lines (if applicable) galleys and low areas that do not get drained from the engine at a refill. This all adds up to the amounted difference in refill and dry fill numbers (about half of a quart give or take usually, depending on the engine). Most of the time when you call some place to get capacity numbers, they vary depending on the technicians experience and knowledge and the source that they are reading the numbers from.

The figures that I listed are from the Toyota Supra Factory Repair Manual originally published by the same engineers that designed the 7M-GTE. You don't get any closer to the original source than a factory repair manual for this reason.

The 20W50 oil is suggested to be used in consistantly hotter operation climates according to the TSRM. 15W40 is the base line viscosity weight numbers suggested to use under normal operation by the TSRM.

1) i was a toyota tech for about a year...until i got tired of the politics there... EVERYTHING with toyota on it said 5.5 quarts...same for the 2jz... if you HONESTLY think a whole quart of oil stays in the engine when you change it out...you are insane.

2) 20w50 can be run in any temp...hence the reason i ts MULTIgrade oil.

3) guess what...that SAME TSRM you hold as a bible...says to torque the hg down to 56ft/lbs .... do you do THAT?

im not gonna argue this anymore...you can think what you want...but my previous statements all stand...

 

[MisterTurbineTwister]

I didn't say that a whole quart stays in the engine after dry fill. I'm not insane. You just don't know how to read a shop manual or a post for that matter. I said a half of a quart. You even quoted me on half of a quart. Go look at the TSRM quart capacitys on a DRAIN AND REFILL and argue it with the engineers that built the engine.

The TSRM also suggests not to run anymore than 6.8 PSI on a turbocharged engine and the stock torque reference for the head bolts hold against the STOCK boost levels far beyond the warranty milage of the cars lifespan.

You start modifying things and the numbers change. If you are running a high flow oil pump, the correct way to increase oil capacity to flow numbers is to run a deeper pan and a swinging pickup to prevent oil starvation. You don't just overfill crap and let it slide.

The multi grade in any viscosity of oil simply pertains to its heat ranges. Heat range numbers change with different viscosity weight numbers.

Aside from my messed up filter, I saw 15-20 PSI increase over a previous fresh oil change with 20W50 when I went to a fresh oil change with 15W40. I can't deny an oil change that will get me into higher PSI levels.

 

[Idealsupra]

I didn't say that a whole quart stays in the engine after dry fill. I'm not insane. You just don't know how to read a shop manual or a post for that matter. I said a half of a quart. You even quoted me on half of a quart. Go look at the TSRM quart capacitys on a DRAIN AND REFILL and argue it with the engineers that built the engine.

The TSRM also suggests not to run anymore than 6.8 PSI on a turbocharged engine and the stock torque reference for the head bolts hold against the STOCK boost levels far beyond the warranty milage of the cars lifespan.

You start modifying things and the numbers change. If you are running a high flow oil pump, the correct way to increase oil capacity to flow numbers is to run a deeper pan and a swinging pickup to prevent oil starvation. You don't just overfill crap and let it slide.

The multi grade in any viscosity of oil simply pertains to its heat ranges. Heat range numbers change with different viscosity weight numbers.

wow thanks for that lesson...

i know how to read fine thank you very much... and according to YOU and your TSRM... YOU said 4.7 quarts for a drain and refill with filter change... hmm 4.7-5.5 is just about 1 QT now isnt it? and i guess EVERY SINGLE DEALERSHIP IN THE COUNTRY...is RUINING engines because they are ALL putting 5.5 quarts in the 7m and the 2jz engines. oh the humanity.

lets see what else...hmmm accroding to YOU...yo have about 15psi at IDLE...hey guess what? thats not RIGHT! because the TSRM says its supposed to be 4.3psi at idle...

if you know ANYTHING you would know thats BARELY enough to float the crank...so we strive for higher pressure...

as for the heat with multigrade oil...thanks i didnt know that my point was it IS multigrade and frankly anywhere in the continental US you could use MOST multigrade oils year round if you choose properly...

im REALLY done arguing....because you are simply contradicting yourself...you MUST have it by the TSRM for one thing...but something else is COMPLETELY different

my MAIN point was that you are preaching that 20w50 was your problem...and maybe your clearances for YOURengine created a problem with 20w50...HOWEVER that does not give you the right to say "EVERYONE WITH A 7M ENGINE DO NOT USE 20W50 CAUSE ITS BAD." thats a retarded statement.... especially considering hey the MANUAL says to use 20w50 for some of the supras.

that is ALL...

 

[MisterTurbineTwister]

Well, .8 Qts isn't exactly a full quart and it isn't exactly half of a quart either. I said about a half a quart give or take, depending on the engine. If it is .8 Quarts and you think it's insane that the engine retains that much oil at a change, it's all there in black and white in the manual. If .8 Quarts is what is retained between a drain and refill, so be it. I see the marking on the dipstick full to the highest level when I put in 5 Qts. and that should be enough oil, right?

I'm sorry if I came off as a jerk, I realy didn't mean to. I just experienced a problem with the oil that I was running under all normal maintenance conditions and I know of a few other people on this forum that have had similar problems running the incorrect viscosity of oil. Moving away from 20W50 corrected the problem and brought higher PSI numbers into the equation that I had not ever previously seen with 20W50.

The oil pressure gauge used to read about 5PSI at idle with my 20W50 oil. It now reads about 8-15 PSI depending on the temperature of the engine and the PSI climbs noticably faster with the 15W40 in my engine.

 

[antman]

man, i fill my shit tell it comes out the valve cover....ya'll don't? :nuts:

 

[MisterTurbineTwister]

I tryed that, but it just started gurgling and smoking, so I drained it and put gasoline and corn syrup in and it took care of things.

 

[IJ.]

Higher pressure with lower viscosity is counter intuitive.

I'd be thinking that your filter was blocked and was bypassing crap into the bearings if this happened to me NOT that 20/50 is too thick to get into the tight clearances and if you're using a non bypass filter it would show up as very low pressure.

 

[MisterTurbineTwister]

That's what I think was happening. I think that the 20W50 was okay until the filter became clogged and then the 20W50 was having a hard time getting past all of the shit stuck in the filter.

Higher PSI and lower viscosity would seem to be counter intuitive. I thought that higher viscosity numbers brought higher PSI levels. pressure is resistance in it's true form, respectfully. Higher viscosity fluids move slower too. I think that the bearings will get more adequate fluid circulation with the 15w40 and it may help the engine to run cooler.

It's all just test data. I'l find out for myself if moving to 15W40 continues to benefit.

 

[IJ.]

I'd be a little concerned that after the "pressure issue" using 10/40 might not fill the now increased clearances .

This will be ok for the first 1000 then as the oil breaks down you might notice the knock again and so starts the vicious cycle of knock/more clearance/more knock and so on.

I went to great lengths to safeguard against this in my build and in the 4000 KM I put on the motor with a LOT of hard cornering and braking it appears to have worked the way I hoped.

 

[MisterTurbineTwister]

That's good to know that you checked and corrected your engine. I think I over projected the problem in my head. It always had normal oil pressure at idle and at least 15 PSI above idle, just not as high as I would normally like to see when the problem was occuring. Usually when you see the main bearings going out, you hear it at idle and under RPM increase or anywhere that the RPM exceeds the oil PSI level needed to float bearings.

I drove the car for about 20 minutes at normal temp and checked it and it seems okay. I'll figure it out come higher miles. There's no other way to find out besides tearing my shit apart and measuring shit.

 

[lagged]

.....or sending the oil out to a lab. i dont know why more people dont do this. you can figure out if the bearings are gonna fail before you can even hear a knock if you send the oil out to get tested.

 

[MisterTurbineTwister]

I think that's a plan for the near future within the next oil change. I didn't have a clean enough pan to drain into to run that kind of test. They could have found all kinds of aluminum from a rotten 727 transmission that was drained into the pan that I used. I'll use a jar cleaned with denatured alcohol to get a clean sample.

I did run a magnet around in the bottom of the oil pan and came out clean of all particles. I didn't get anything. Still, I think a test would be simple enough, I just have to find a lab to do it.

 

[IJ.]

Bearing material is non ferrous.

 

[MisterTurbineTwister]

it usually bonds with iron deposits upon heat (from friction), but the magnet is only worth so much. There were no metal particles at the bottom of the pan or at the bottom of the pan used to drain in. I honestly think it's okay, but I'll do my lab testing and further research as time goes by.

 

[lagged]

just FYI, the lab that my dad uses (marine surveyor) and probably most labs that do lube oil analysis have a kit that you must submit the oil in. you draw out the oil with a syringe (not a turkey baster..) and deposit the oil into a plastic (*provided, wont react with fuel, etc) tube. it is a very small amount of oil.

so whatever type of pan you use to do your oil changes dont matter, you need to use the proper equipment to send the oil out anyway.

 

[MisterTurbineTwister]

I understand that they have supplied testing equipment, but I don't want them to tell me that they found aluminum and antifreeze and other things in the sample from other fluid changes that I have used this drain pan for. I figured that a glass jar would collect the fewest contaminates to fetch a good sample from the oil pan and only the oil pan while it drains into the catch pan underneath. Just to get something clean to pull a sample with their supplied equipment from.

 

[lagged]

hah, you dont collect the oil from whatever youve drained it into! you feed a CLEAN tube down the dipstick tube and suck up the oil through there into a TINY container (ALSO CLEAN BTW).