OK so I'm investigating this knock....tips? anyone have this symptom before?

[Figit090]

A friend is letting me bring my supra by his work tomorrow to listen to it from underneath to pinpoint a knocking sound...and before I go, I had a question about my knock.

I'm afraid it's rod knock. However, another member thought he had RK and low and behold it was his clutch/flywheel...they were loose. can i check that on the W54 (n/a 5spd) just by removing some plates and taking a peak??

Here's the type of knock;

ONLY on warm starts, i hear the knock. hits about 6-8 times on average, then goes away, then i see the oil pressure start to rise. this all happens in a few seconds, and i dont know that it has anything to do with oil pressure.

the car starts smooth from a cold start!! It usually revvs nice and smooth all the way through 3500 rpm (i usually dont rev higher).

however, if i drive for a while, park it for at least 45minutes to as much as 2 hours and come back, it will do the knocking on startup again. It starts and comes to a low idle immediately rather than revving like on a cold start, so i figure that's part of why its so noticeable during a "warm" start...its not forced up past 1k RPM in the first second like when its cold.

anyone ever had this happen? My friend said that it would be weird for rod knock to do that when the engines still warm or hot... it will do it more when it's cold. I thought maybe its rod knock and its just the oil not getting to the bearings to hide it, but it doesn't make sense that it would knock on a warm start but if i let it sit for more time...overnight...it would go away... it doesnt make sense!

so frankly, I'm worried it might be rod knock, but it doesn't seem to have the right characteristics. prove me wrong? It feels rough between 2-3k RPM but it doesn't really knock..

i'll be listening it to it tomorrow, any tips for that are welcome but i'll probably figure it out. there will be an experienced mechanic there as well. so yeah if anyone has had this symptom and know whats going on i would appriciate any help.

i know RK has been posted to death but I dont remember reading any post about this type of knocking. its usually just when revving, which for me isn't that bad.

 

[iMod]

I don't know very much about mechanics, but my friends do. Most of the time when their cars tick or knock they say it's the "Tick Of Death". They say it happens when their oil is low. They usually put some oil in it and it fixes the problem.

 

[Figit090]

i'm running one quart over.


i was thinking of switching weights though...right now i'm on 5W-30

 

[cuel]

For Rod Knock: http://www.supramania.com/forums/showthread.php?t=20486

For oil: http://63.240.161.99/motoroil/
More oil: http://www.supramania.com/forums/forumdisplay.php?f=108

As far as the "Tick of Death." Any knuckle-headed moron who waits until the motor starts making noise to check the oil deserves what he gets. You should check everything on a weekly basis. Every fluid, tire pressure, all lights, EVERYTHING!!! Takes a whopping 10 mins. You waste that on a smoke break...

 

[iMod]

lol just for the record, I never get the tick of death =P

 

[BorHor]

You gave the wrong tranny name. It is a w58 not 54. As for problem I have no clue sorry = /

 

[AJ'S 88NA]

How many miles on the motor? Rod knock can be a tapping to a knocking sound. Could also be piston slap, valve lash needs set or sticking lifters, if the oil changes have been far and in between, could be all of the above. And no there is no inspection plate on the W58.

 

[johnathan1]

I STILL think it has something to do with your cams/valves...are you running synthetic oil? I remember reading something about this a LONG long time ago on the supras e-mail digest...It ended up being a clogged cam oil passage that was causing the tick on startup...

 

[thefixer0508]

in my experience Mechanic over 15 years auto and large diesel if it goes away when your oil pressure rises plan on tearing down the motor or replacing i am not saying its toasted but the way you describe plan on it sooner than later finishing off with a loud bang and a big oil slick

 

[cuel]

Oh yeah, the trans.(W58). There is a dust shield on the front bottom of the bell housing. you might be able to remove it and see if you can move the flywheel/pp. Really don't think that's the problem, as it would do it all the time, and probably cause a vibration as well.

As far as the knock... I had a Chevy truck(5.7l v-8) in the shop a while back that had similar symptoms. Turned out to be the #1 main bearing. It, however, would knock like you describe hot or cold.

 

[Figit090]

Ok, first of all I take care of cars. its only got 111k miles on it. The previous owners, come to find did not take very good care of it. I know it takes 10 seconds to check my oil. I do it all the time. and i run a quart over. me letting it get low isn't the case. previous owner? hell if i know... and i don't smoke

Dust shield...i'll take a look when it's up on the lift. thanks.

john - i remember you mentioning that before. i'm not running synthetic. I had the head cleaned and lapped so any passages should be fine. either way it's a knock not a tick, and as far as we can tell, it's in the bottom end. I'm leaning away from the top end being the problem.

so i'll prepare myself to hear it to my face that i have rod knock. i dont know what else it could be.

HOWEVER i do feel lots of vibration in my clutch pedal, shifter, and lighter vibration in the gas pedal but i think that's just because the vibrations are going through lots of stuff. so in response to assuming i would have vibrations, i have them! heh..

here's a question for those that have actually had rod knock;

can you feel it through the shifter and/or other parts of the car while you're driving or sitting in the car with the clutch let out? what about with the pedal depressed?? i noticed with my clutch pedal pushed in i could feel the vibration a lot more in the pedal and it got a tad bit louder... that's part of why i was wondering about the clutch and whether or not it should be able to transmit vibrations to my stickshift while depressed....

 

[cuel]

lol, sorry bro, wasn't pointing at you. Was more pointing at the friends mentioned in a different post.

Oh yeah, make sure you have a stethoscope for pinpointing the exact location. It works much better than a broom handle, tubing, long screw driver, etc.

 

[Figit090]

hah, i figured after re-reading it. at first i felt defensive like you accused me of such blasphemy! but then yeah, i got it. sorry if i seemed like i was touchy there.

thanks for the tip, i almost forgot to throw that in my car...i'll surely forget tomorrow if i dont do it now. so yeah i'll go do that.

where are some good places to poke for RK? oil pan? side of block?

i'm still curious about that vibration issue with the clutch if anyone hasn't read my post at the top of this page, please do! thanks.

i'll be back to read this later tonight and then tomorrow, most likely tomorrow i'll post but dunno about tonight. thanks for all the help guys, wish me luck!

oh and where's that dust cover or whatever? bottom of tranny? if someone could describe it...shape/number of bolts...anything i need to know before removal....

----------EDIT----------
plans changed due to schedule conflict, i'm lifting the car tomorrow, given no more issues arise.

 

[AJ'S 88NA]

hah, i figured after re-reading it. at first i felt defensive like you accused me of such blasphemy! but then yeah, i got it. sorry if i seemed like i was touchy there.

thanks for the tip, i almost forgot to throw that in my car...i'll surely forget tomorrow if i dont do it now. so yeah i'll go do that.

where are some good places to poke for RK? oil pan? side of block?

i'm still curious about that vibration issue with the clutch if anyone hasn't read my post at the top of this page, please do! thanks.

i'll be back to read this later tonight and then tomorrow, most likely tomorrow i'll post but dunno about tonight. thanks for all the help guys, wish me luck!

oh and where's that dust cover or whatever? bottom of tranny? if someone could describe it...shape/number of bolts...anything i need to know before removal....

----------EDIT----------
plans changed due to schedule conflict, i'm lifting the car tomorrow, given no more issues arise.

I've had the rod knock transfer to the shifter, clutch, etc. Not so much as a vibration, but you could feel it. I don't know of a dust cover that will let you see into the clutch area. There is one at the bottom of the bell housing, but all you would be able to see is front of the flywheel. I think the W154 has a side inspection plate.
I thought it was funny also about your buddies fixing their RN when their oil was low by adding oil to it :biglaugh: wish it was that simple.

 

[johnathan1]

You're "lifting" the car tomorrow?

 

[Figit090]

haha...whoops. lifting as in on a huge vehicle lift. listen from underneath, while standing :icon_razz

friend adding oil to remove rod knock? huh?

 

[AJ'S 88NA]

I don't know very much about mechanics, but my friends do. Most of the time when their cars tick or knock they say it's the "Tick Of Death". They say it happens when their oil is low. They usually put some oil in it and it fixes the problem.

Wasn't your post.:biglaugh: