Tired of rod knocks...

turbonicsperformance · 11-03-2011, 11:30 PM

Quote:

Originally Posted by cre

With all the trouble you're having I'd make sure the crank's straight anyway... It's not the stiffest of metal, and they're quite long. I have seen one go south pretty quick myself (never checked one that was out for less than a week though, but still not a bad idea).

Yes, they look the same but the GTE flows a good amount more to account for all the additional sources of pressure drop: turbo, cooler and oil squirters. I'd guess 25% more or so.

If you can touch the oil it's running too cool. The stock cooler is PRESSURE based, not temp. If the valve is stuck open or the spring is weak it'll stay open, over cool the oil and tank your oil pressure. I HIGHLY recommend you just ditch it and get a thermostat in there.

How are you measuring the oil pressure? Not with the stock gauge I hope. Low pressure is fine below 3K (according to Toyota) but 4psi is lower than any GTE I've worked on... or GE for that matter. Toyota says 4.3psi or more is fine but in a healthy engine I don't think I've ever seen it lower than around 6 or 7 warm.

when it was first built it idled around 10 12 psi warm and would top around 40.After about 1k miles it would idle around 6-7psi and now it idles at 3-4 psi and is knocking pretty loud. You can't hear it under a load or at idle it makes noise from 1800-3000 rpm any higher or lower its silent.
does anyone sell a full kit to convert it to a full flow thermostat system? or am i gonna have to piece one together?
everything was checked before the engine was put together the crank is straight as well as the block it was checked on a machinists table and showed less than .001 difference anywhere.

I'm really thinking i put the ge pump in it hopefully the crank is fine this time. last time it happened i had one bearing with what loooked like a burnt spot but no missing material or scoring on the crank or bearings...

87hilux7mge · 11-04-2011, 04:50 AM

i was going to suggest a bent crank and/or out of spec mains. id have the block and crank checked for align straightness.

3 sets of bearings is pretty hefty for these, thats ruff though, sorry man, hope you figure it out soon.

cre · 11-04-2011, 04:58 AM

Nope, no one makes a kit that I know of. It's easy though. 1/2" or -10AN hose, block adapter for remote mount oil filter, remote oil filter head, thermostat.... and whatever fittings you need. A sandwich plate with the ports on the side is far easier to work with than one where they come straight out... 90? fittings are more restrictive and depending on your IC piping size have very little clearance. I've been curious about how well a water based oil cooler setup would work on a mildly built 7M....

The GE pump isn't wonderful but people do get by with them in N/A-T setups without issue. I'd try eliminating the stock oil cooler as a suspect first (only temporarily). It's easy to check if it's the source of the problem: remove the filter, remove the cooler/filter adapter or whatever you want to call it, install a GE oil filter nipple and directly mount an oil filter... run engine.

A burn spot, no scoring and no material lost? Wow, you caught that quick.... of course if I were dealing with the same engine I'd have very finely tuned hearing too.

Well, you're having shit luck that's for sure, they're not my favorite platform but they're usually more reliable than what you've had to deal with. Are the knocks occurring in the same location? Is the engine level (not tipped on any given axis)?

turbonicsperformance · 11-04-2011, 08:05 AM

ill try that.
the thing with the burnt spot was that it was just as loud then as it is now. it never gets louder it just makes the exact same sound the same volume but this time i have some flaking in my oil so i know its further gone.

anybody with experience hard mounting these know if it makes a difference? I've heard of people having issues with hard mounting certain engines because at a certain hertz they match the frequency the oil flows and it causes the oil surface tension to break... and miatas are known to chew rod bearings with aftermarket crank pulleys for the same reason. just a thought anyone running solid mounts?

the engine sits 2 degree tilted not enough to make any sort of difference. and the first time it was rod #3 ill know when i pull it apart if its the same rod.the first set of bearings were run for about 15 minutes and started making noise along with the head (there was a blocked passage in the head) i didn't pay attention to which bearing it was because I knew the head was the issue. everything mic'd good on the crank and i cleaned all the passages AGAIN got a new head cleaned it THOROUGHLY and put it all back together.

cre · 11-04-2011, 08:39 PM

Solid mounts are miserable; If you want something more rigid look at the pre89 mounts. Harmonics breaking the surface tension isn't an issue anyone I know of has ever gone through in one of these engines (definitely not at power levels like you're seeing); You're grasping at a straw that isn't there. It's not worth the stress on the frame as it's not going to fix anything.

You sure there wasn't still crap from that blockage in the head stuck in there and waiting like a timebomb? You did miss it the first time. Could have been debris got stuck in the oil cooler too; Did you flush it?

turbonicsperformance · 11-05-2011, 04:30 AM

Quote:

Originally Posted by cre

Solid mounts are miserable; If you want something more rigid look at the pre89 mounts. Harmonics breaking the surface tension isn't an issue anyone I know of has ever gone through in one of these engines (definitely not at power levels like you're seeing); You're grasping at a straw that isn't there. It's not worth the stress on the frame as it's not going to fix anything.

You sure there wasn't still crap from that blockage in the head stuck in there and waiting like a timebomb? You did miss it the first time. Could have been debris got stuck in the oil cooler too; Did you flush it?

the head was replaced with a different one and the engine was torn down 100% and all passages were cleaned and and bearings replaced.
the oil cooler and lines were replaced when the engine was torn down and head replaced (i just happened to get a new one at the same time).
and the mounts are solid not for rigidity but for the pure problem of clearance. the miata is a short car and the oil pan sits 1/8th inch off the steering rack and still doesn't clear the hood. I've gotten use to them and don't really notice the vibrations etc. any more. it just makes riding in any other car more comfortable lol it also has the stiffest springs available for the car along with coilovers setup for drift. i basically dd a race car. You gotta pay to roll in style (:

cre · 11-05-2011, 12:43 PM

I'd still want mounts with SOME dampening there; Even if I had to build a mould and cast it myself.

Yeah, they're tiny... smaller than my MR-2. Fun rides these cars.

Sonyps307 · 11-05-2011, 03:49 PM

R u running a cheap aftermarket solid crank pulley they also wipe out the bearing on a 7m. Can the stock oil gauge even read 6 psi.

11-04-2011, 04:50 AM	#2
87hilux7mge walbro fp Join Date: Dec 2010 Location: spokane Posts: 479	i was going to suggest a bent crank and/or out of spec mains. id have the block and crank checked for align straightness. 3 sets of bearings is pretty hefty for these, thats ruff though, sorry man, hope you figure it out soon. __________________ 87 toyota 4x4 single cab short box pickup, 7MGZE.

11-04-2011, 08:05 AM	#4
turbonicsperformance 3" Exhaust Join Date: Apr 2010 Location: sarasota fl Posts: 194	ill try that. the thing with the burnt spot was that it was just as loud then as it is now. it never gets louder it just makes the exact same sound the same volume but this time i have some flaking in my oil so i know its further gone. anybody with experience hard mounting these know if it makes a difference? I've heard of people having issues with hard mounting certain engines because at a certain hertz they match the frequency the oil flows and it causes the oil surface tension to break... and miatas are known to chew rod bearings with aftermarket crank pulleys for the same reason. just a thought anyone running solid mounts? the engine sits 2 degree tilted not enough to make any sort of difference. and the first time it was rod #3 ill know when i pull it apart if its the same rod.the first set of bearings were run for about 15 minutes and started making noise along with the head (there was a blocked passage in the head) i didn't pay attention to which bearing it was because I knew the head was the issue. everything mic'd good on the crank and i cleaned all the passages AGAIN got a new head cleaned it THOROUGHLY and put it all back together. __________________ 92 miata 7mgte swap forged pistons,studded mhg, 3 inch dp with a glass pack,blowthrough MAF-T,550cc inj, act stage 2 clutch, fmic kit, greddy rs, full wire tuck, rx7 lsd rear with 4.10s. 15psi "ct26-A"??(waiting on dyno #s) if anyone knows whats up with my turbo let me know it has a larger comp wheel nicer machining and 6 dual fins rather than 5? its confusing and keep finding too much contradicting info. would LLLLLOOOOOOOOVVVVVVVEEEEE a compressor map Last edited by turbonicsperformance; 11-04-2011 at 08:12 AM.

11-04-2011, 08:39 PM	#5
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Solid mounts are miserable; If you want something more rigid look at the pre89 mounts. Harmonics breaking the surface tension isn't an issue anyone I know of has ever gone through in one of these engines (definitely not at power levels like you're seeing); You're grasping at a straw that isn't there. It's not worth the stress on the frame as it's not going to fix anything. You sure there wasn't still crap from that blockage in the head stuck in there and waiting like a timebomb? You did miss it the first time. Could have been debris got stuck in the oil cooler too; Did you flush it? __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

11-05-2011, 12:43 PM	#7
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	I'd still want mounts with SOME dampening there; Even if I had to build a mould and cast it myself. Yeah, they're tiny... smaller than my MR-2. Fun rides these cars. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Tired Engine	WhosYourSupra	Non-Generation Specific Questions	2	03-06-2007 06:34 PM

11-04-2011, 04:58 AM	#3
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Nope, no one makes a kit that I know of. It's easy though. 1/2" or -10AN hose, block adapter for remote mount oil filter, remote oil filter head, thermostat.... and whatever fittings you need. A sandwich plate with the ports on the side is far easier to work with than one where they come straight out... 90? fittings are more restrictive and depending on your IC piping size have very little clearance. I've been curious about how well a water based oil cooler setup would work on a mildly built 7M.... The GE pump isn't wonderful but people do get by with them in N/A-T setups without issue. I'd try eliminating the stock oil cooler as a suspect first (only temporarily). It's easy to check if it's the source of the problem: remove the filter, remove the cooler/filter adapter or whatever you want to call it, install a GE oil filter nipple and directly mount an oil filter... run engine. A burn spot, no scoring and no material lost? Wow, you caught that quick.... of course if I were dealing with the same engine I'd have very finely tuned hearing too. Well, you're having shit luck that's for sure, they're not my favorite platform but they're usually more reliable than what you've had to deal with. Are the knocks occurring in the same location? Is the engine level (not tipped on any given axis)? __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

11-05-2011, 03:49 PM	#8
Sonyps307 Lexus & 550's Join Date: May 2010 Location: Baltimore Posts: 526	R u running a cheap aftermarket solid crank pulley they also wipe out the bearing on a 7m. Can the stock oil gauge even read 6 psi.