0w30 instead of 5w30 rod knock gone

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why does it work?

tried on 4 different motors b and d series Honda.
switched from mobil1 5w30 to mobil1 0w30 and knock is gone even at cold start...
drove the cars for months after daily and no rod knock
and the engine feels smoother to my ear at least
 
there is no way a "rod knock" is fixed with different motor oil, if there is a "rod knock" then the bearing wear is too great and even thicker oils won't really come close to solving this "rod knock" of yours, and no you didn't have a rod knock if oil fixed it.
 
Originally Posted By: Gasbuggy
You have 4 motors with rod knock?


He has me beat.. LOL

Originally Posted By: fuzzysig
why does it work?

tried on 4 different motors b and d series Honda.
switched from mobil1 5w30 to mobil1 0w30 and knock is gone even at cold start...
drove the cars for months after daily and no rod knock
and the engine feels smoother to my ear at least



Oh, brother.

It's not rod knock, it's a typewriter sound... right?
 
Do they use hydraulic lifters? I could see maybe a 0w-30 pumping up a worn out lifter quicker than a conventional 5w-30. My Cherokee lost a bit of top end noise of some sort when I ran a 5w-30/20 mix in it.

But it wasn't a rod knock


Originally Posted By: Pop_Rivit
Motor oil doesn't fix rod knocks.


I think some 85w-140 would clear up a bit of noise! haha. Then it would probably spin a bearing from the 140 not flowing at all!
 
Just to satisfy my own curiosity, I hope there is a board member on here that can tell us what exactly this noise is. A had a 1995 Civic with a d16 that made an awful noise when cold but was dead silent after it was up to temp. I adjusted the valves and ruled them out. I knew it wasnt valves anyway because this noise was only UNDER LOAD. I just always let it warm up several minutes and never had any issues. I sold it to a buddy for cheap and he drove it for years with never an issue but the noise was always there. Dead silent at normal operating temp. I know it has to be piston slap or rod bearings on the high end of tolerance but never knew for sure. It sure wasn't worth tearing into just for curiosity. This was a 1995 d16 SOHC. D16Z6 if memory serves...
 
Originally Posted By: AndyinAL
Just to satisfy my own curiosity, I hope there is a board member on here that can tell us what exactly this noise is. A had a 1995 Civic with a d16 that made an awful noise when cold but was dead silent after it was up to temp. I adjusted the valves and ruled them out. I knew it wasnt valves anyway because this noise was only UNDER LOAD. I just always let it warm up several minutes and never had any issues. I sold it to a buddy for cheap and he drove it for years with never an issue but the noise was always there. Dead silent at normal operating temp. I know it has to be piston slap or rod bearings on the high end of tolerance but never knew for sure. It sure wasn't worth tearing into just for curiosity. This was a 1995 d16 SOHC. D16Z6 if memory serves...


It is piston slap and is due to short skirts and excessive piston to bore clearance that gets taken up when things expand as they get heat into them.

Rod knock happens when the oil thins, ergo, you won't get rod knock on startup as that's when the oil is the thickest. An engine with excessive rod to journal clearances is usually quiet on start-up and gets progressively louder as it warms and the oil thins.

In comparison piston slap is most pronounced when an engine is stone cold and will get progressively quieter, usually going away completely as the engine gets up to temperature.


They can sound very similar but how they manifest is completely opposite.
 
I went through a single cam stage when I was looking for a car

3 of them had a rod knock d16y8 is notorious for it.
almost all of them go out that way and more than half are developing one as we speak...
first one I bought a used core the guy said ran fine turns out had a spun bearing
I had to get the car out of the garage like yesterday so I went to pick and pull and got a used bearing from 91 civic of same color. sandpaper the rod journal and slap that sht in.

motor seized halfway down the street I put it in gear and rocked that btch loose. it started again lol.( I was pretty surprised)
but had a massive rod knock...
drained the 5w30 next day and put 0w30 mobil one.
started up and after few days the rod knock only show up for less than a second during startup.
drove that car for 8 months
then I decided to test this and switched back to 5w30. rod knock came back right away and I sold it...

my wife blew up a motor in her work civic
I swapped a d16y7 from junk yard. had a rod knock put 0w30 rod knock gone. drove it for another year and a half daily
same with my buddys car. I tld him to try and he did. drove the car for another year before it blew up

had a built gsr motor for 2 years, made a mistake of using felpro cam seals and supertech valve seals after fixing headgasket leak. they both leaked like mofo and oil pump went out after 200 miles due to oil loss. I put new oil in it and drove it for 2 days with bad oil pump not knowing that the engine was a dead man walking since it didn't make any weird noises and ran fine. (the only 2 days that I didn't have my oil pressure gauge hooked up after rebuild.. it fn got me good...

on the second day it started getting a lot louder so I took the vc off and pretty much found a dead motor full of metal shavings and it was still running with the 0w30 in it.

but those are extreme cases lol
usually I can hear and feel the motor running and cold start smoother when switching from 5w30 to 0w30
 
its definitely rod knock I can hear it with a stethoscope
it didn't go away after warm up on 5w30 it just wasn't as loud as during cranking before oil pressure builds up
changing oil wouldn't affect piston slap
 
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Originally Posted By: fuzzysig
I went through a single cam stage when I was looking for a car

3 of them had a rod knock d16y8 is notorious for it.
almost all of them go out that way and more than half are developing one as we speak...
first one I bought a used core the guy said ran fine turns out had a spun bearing
I had to get the car out of the garage like yesterday so I went to pick and pull and got a used bearing from 91 civic of same color. sandpaper the rod journal and slap that sht in.

motor seized halfway down the street I put it in gear and rocked that btch loose. it started again lol.( I was pretty surprised)
but had a massive rod knock...
drained the 5w30 next day and put 0w30 mobil one.
started up and after few days the rod knock only show up for less than a second during startup.
drove that car for 8 months
then I decided to test this and switched back to 5w30. rod knock came back right away and I sold it...

my wife blew up a motor in her work civic
I swapped a d16y7 from junk yard. had a rod knock put 0w30 rod knock gone. drove it for another year and a half daily
same with my buddys car. I tld him to try and he did. drove the car for another year before it blew up

had a built gsr motor for 2 years, made a mistake of using felpro cam seals and supertech valve seals after fixing headgasket leak. they both leaked like mofo and oil pump went out after 200 miles due to oil loss. I put new oil in it and drove it for 2 days with bad oil pump not knowing that the engine was a dead man walking since it didn't make any weird noises and ran fine. (the only 2 days that I didn't have my oil pressure gauge hooked up after rebuild.. it fn got me good...

on the second day it started getting a lot louder so I took the vc off and pretty much found a dead motor full of metal shavings and it was still running with the 0w30 in it.

but those are extreme cases lol
usually I can hear and feel the motor running and cold start smoother when switching from 5w30 to 0w30


lolwut I've worked on so many abused d16y7/8s they don't all get rod knock that's ridiculous.

Willing to bet someone didn't properly torque the crank pulley bolt after a timing belt job...
 
d16 is essentially a stroked d15 so the load on bearings is higher. and I belive some kind of oil pump design flaw = many spun bearings in them.
I hear them every week blowing up for same [censored] reason. rod knock or spun bearing.
my friend jus blew his d16y7 spun bearing... and his other single cam civic also has a slight rod knock.
 
Originally Posted By: fuzzysig

d16 is essentially a stroked d15 so the load on bearings is higher. and I belive some kind of oil pump design flaw = many spun bearings in them.
I hear them every week blowing up for same [censored] reason. rod knock or spun bearing.
my friend jus blew his d16y7 spun bearing... and his other single cam civic also has a slight rod knock.


bull**** they're letting them run low on oil is what they're doing. you can boost a stock d16 all day long with just arp head studs but they will consume lots of oil when in vtec
 
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Originally Posted By: fuzzysig
I went through a single cam stage when I was looking for a car

3 of them had a rod knock d16y8 is notorious for it.
almost all of them go out that way and more than half are developing one as we speak...
first one I bought a used core the guy said ran fine turns out had a spun bearing
I had to get the car out of the garage like yesterday so I went to pick and pull and got a used bearing from 91 civic of same color. sandpaper the rod journal and slap that sht in.

motor seized halfway down the street I put it in gear and rocked that btch loose. it started again lol.( I was pretty surprised)
but had a massive rod knock...
drained the 5w30 next day and put 0w30 mobil one.
started up and after few days the rod knock only show up for less than a second during startup.
drove that car for 8 months
then I decided to test this and switched back to 5w30. rod knock came back right away and I sold it...

my wife blew up a motor in her work civic
I swapped a d16y7 from junk yard. had a rod knock put 0w30 rod knock gone. drove it for another year and a half daily
same with my buddys car. I tld him to try and he did. drove the car for another year before it blew up

had a built gsr motor for 2 years, made a mistake of using felpro cam seals and supertech valve seals after fixing headgasket leak. they both leaked like mofo and oil pump went out after 200 miles due to oil loss. I put new oil in it and drove it for 2 days with bad oil pump not knowing that the engine was a dead man walking since it didn't make any weird noises and ran fine. (the only 2 days that I didn't have my oil pressure gauge hooked up after rebuild.. it fn got me good...

on the second day it started getting a lot louder so I took the vc off and pretty much found a dead motor full of metal shavings and it was still running with the 0w30 in it.

but those are extreme cases lol
usually I can hear and feel the motor running and cold start smoother when switching from 5w30 to 0w30


Yeah... I am a Honda guy too. Somewhat. I like my Honda, I like my other car more. Sourced a D16Y7 (? Y8? It's a year 2000 car so whatever, going into a previous generation EJ1, parts from all years in the range) and I'm going to verify the engine's health soon, with compression tests and such. Did not think of pulling VC, to look for shavings (? Thought you looked in the oil pan. Anyways) I'm probably going to put 0W-20 in it, just like I do now, since Honda says you can. They back-spec'd it, and put 5W-20 in since 2001.. 5W, 0W, both are 20 at operating temp.

You sure had some [censored] Hondas. The Honda forum would probably have guided you back to some nice builds. Especially on that Y7.

I would also agree with you that quality 0W oil can be felt in smoothness, mostly on cold start followed by turn-key-and-drive, and depending on how the engine takes to the oil in it even if via the butt dyno, during the whole run. I started the 0W pursuit about three years ago and have been using 0W and 5W when 0W was not around ever since. No bad results from oil choice. Engine situations are a different story.

Have a nice day, and that GSR.. B18?
 
kingcake yes it is a stroked d15
just like b series
Honda doesn't bore out the cylinders they increase stroke and deck height going from b16 to b18 with exception of b20

d15
bore:75.00
stroke:84.50
deck height:207.00

d16
bore:75.00
stroke:90.00
deck height:212.00

d17
bore:75.00
stroke:94.00
deck height:212.00

as you can see Honda didn't increase displacement by increasing bore. but by increasing stroke and deck height. on both d16 and d17 motors


junk yards are full of these [censored] civics with rod knock or spun bearing.
most of the cars come there in almost mint condition body but blown motors
 
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I had a Civic VTI with b16a2 believe it is direct swap to lesser models. Only had issues with valve steams.
 
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