7m noise.. please help

[Stomps]

wish i had some good news to share but...no...

noise sounds like its coming from the block, round half way up, round cylinders 1,2..

so far the guesses i have had from credible sources that heard it are: some sort of rod knock, or some sort of piston noise...(something embedded in the piston slapping the head..)

in either case this warrants a rebuild.. so on that note does anyone have any 7m performance parts laying round.. ie.. forged pistons, rods etc...

Thanks
Stomps

[whatthe?]

Bugger, sorry to hear dude. Still, a good excuse to build a nice strong 7M has now arisen for you. Ebay is your friend for cheap forgies and rods

[Stomps]

yeah, that sorta news was enough to ruin my day pretty good... especially coz i was planning to buy new turbo etc...

Oh well, like you said a nice strong motor is a good place to start..

i was thinking 1j, but something inside me tells me to stick with the pOO..

Now to get some cash...

Anyone know anybody that robs banks??

Stomps

[oldcorollas]

compression test.

if thats ok, then whatever it is will wear itself out eventually



i'm kidding....


hmm.. rod knock etc..... haven't run out of oil? can you check oil pressure?
pickup could have broken off.. could be something blockign the pickup, oil pump cracked etc...

ie.. may not be full rebuild just yet

[Stomps]

nah, oil level and pressure is fine...

Thats a good point though, i think what i will do is try to find some sort of bunky to get around in, otherwise i cant afford to have my car off the road.. Then i can start pulling things out and having a look..

i might still go for the rebuild later, considering i want to run higher boost etc...

Thanks

Stomps

[EldarO]

last time you changed your oil?

if you changed it very recently it could be the wrong grade....?

idea, buggers me as to what it could be, rod knock sounds a bit iffy if the frequency of the noise doesnt increase with engine RPM...

so, it only does it under load? i.e. under boost?

Eldar.O.

[Stomps]

i had a better listen today, it does increase with rpm, goddamit

i do my own oil changes and always use the same oil, last one was done within 5000k's

actually due for one soon, was talking to a bloke who said the Mobil 1 oil i always use, and was told to use may be a bit thin for the motor, causing oil pressure issues, especially under heavy load..

boost seems to have nothing to do with it, actually seems to go away a bit under higher boost, but i havent exactly been folgging it so i cant know for sure...

cheers all for the input/ideas/advice,

please if you think of anyhting else, share...

Stomps

[EldarO]

change the oil, and filter, chuck in some heavier grade stuff, worst case senario, you'll lose $50 or so.

worth a shot.

Eldar.O.

[oldcorollas]

i had a better listen today, it does increase with rpm, goddamit
i do my own oil changes and always use the same oil, last one was done within 5000k's
actually due for one soon, was talking to a bloke who said the Mobil 1 oil i always use, and was told to use may be a bit thin for the motor, causing oil pressure issues, especially under heavy load..

mobil 1 is fine as long as it doesn't get too hot, and you don't have massive bearing clearances..

this whole perception that it is "thin" comes from it's low viscosity when cold... which is the whole point of having a 5W oil
when cold it is thicker than when hot... but normal oils are MUCH thicker when cold than mobil 1..

>Occurs more under load, but can be heard very faintly free revving..
>Tappety noise but louder
>possibly loose harmonic balancer bolt?

if it was a fuggered oil pressure/pump thing, then more load should make it much worse, as would more rpm...
probably not HG (unless you do a compression test to be sure ) as you say it's steel, and it would need to be a fair leak to be able to hear it going between cylinders...

could be crank pulley bolt.... but you say it sounds in upper half?

could be cam pulley bolt? maybe similar sound to harmonic balancer bolt, but half the rpm. (can you guesstimate if the sound is engine speed or half engine speed? ie, valve tapping speed or faster??)
it could be ring/ringlands or gudgeon pin, or piston.. but that would be fairly nasty, and should lead to some other indication... pin? wouldn't show up as compression or smoke or blowby, but how often to pins fail or have issues?

>noise sounds like its coming from the block, round half way up, round cylinders 1,2..
>so far the guesses i have had from credible sources that heard it are: some sort of rod knock, or some sort of piston noise...(something embedded in the piston slapping the head..)

that noise could easily be coming from the cam pulley as well... piston actually slapping head requires either big or little end to have failed by more than 1mm.. and would make a heck of a racket
hmm.. piece of broken spark plug insulator hitting head? it's possible... pull out plugs and look down bore with torch.. rotate engine to see more of the piston top and also check bore for scoring..

at a guess.. if the rod ends were rooted, then if you were to sayy... put piston halfway down bore, then use a breaker bar and socket (or something similarly solid, and goes both ways) to move the crank back and forth a bit... if it was rooted, then the crank would move without the piston moving... if a small crank movement both ways moves the piston still, then rod ends might be ruled out...

does it sound nasty? or just a new noise? does it sound like someone is whacking your elbow with a hammer? (how i feel whenever i hear rod knock )

[Stomps]

just new noise, but nothing i have heard before.. my old motor developed a massive knock and ripped the bore a new arsehole, sounded much much worse then this..

my motor has always sounded a bit tappety, louder then my old ones, but this sounds different.. i will have a good look inside each sparkplug hole tomorrow, im betting whatever it is happened in number 2...

i had something similar happen before.. i dunno what, but something got into 2 and made a mess of my spark plug, actually flattened the points together, could be similar but sounds more even and consistant then that..

cheers

P.S thanks Stu, you're like an automotive encyclopedia, but better.. rep for joo

[lumpy]

Had a similar noise with a 7m-ge, we were on a road trip and just had to grin and bear it for the last 1000kms. Turned out to be the crank pulley - they get loose and wear out the woodruff key and slot, you often can't feel it being loose as the fanbelt etc holds it tightly. The noise starts out like a light clickety and finally becomes an ominous banging rattle. The bolt holding it can still feel really tight too, it's only when you take it off that you see the damage.

Very common fault on some M engine generations, we tried to re-shape a larger woodruff key and pack it all with brass shim and loctite. Lasted about 30kms before the noise came back. Ended up tossing the engine for a 1jz.

Good luck with it all.

[crowncustom]

Could be a gudgeon pin?

[Hydra]

Had a similar noise with a 7m-ge, we were on a road trip and just had to grin and bear it for the last 1000kms. Turned out to be the crank pulley - they get loose and wear out the woodruff key and slot, you often can't feel it being loose as the fanbelt etc holds it tightly. The noise starts out like a light clickety and finally becomes an ominous banging rattle. The bolt holding it can still feel really tight too, it's only when you take it off that you see the damage.

Very common fault on some M engine generations, we tried to re-shape a larger woodruff key and pack it all with brass shim and loctite. Lasted about 30kms before the noise came back. Ended up tossing the engine for a 1jz.

Good luck with it all.

This seems to be the downfall for 1G's as well... killed my 1G-GE, almost caught my 1G-GTE (but I think I can save it!!).

Going to throw it together tonight, with any luck the pulley is still OK as is the crank. I think i'll use a mallet to ensure the pulley is on all the way

[Stomps]

yeah, the rebuild is going ahead.. getting some eagle rods, and oversized CP pistons, found them on special in the U.S. i know eagle rods are good but has anyone heard of C.P pistons?

are they good/bad/average.. keep in mind i am on a budget, so please dont compare them to HKS or TRD items..

will they be good enough for 450rwhp??

Stomps

[Stomps]

UPDATE:

i gave it an oil change with some chunkier oil today, seems to shut it up a little, but not enough.. ie. problem is still there.. FARK..

anyway, ppls seem to think that CP pistons are good, and Eagle rods are safe up to 1000hp, which, lets face it, i will be getting nowhere near..

Pistons and Rods will be orfered soon, keep an eye out for a new build up thread... This is gonna be fun...

Stomps