New Engine Noise post-Oil Cooler Install
 

Over the weekend, I had an uneventful install of a modified Modshack DIY oil cooler with the help of JB1. So far, things seem to be going very well. No leaks and the temps have dropped by about 20F.

One thing I've noticed is that there seems to be a new sound from the front of the car (noticeable only while in the car, can't really hear it from outside but then again, I don't have someone to help blip the gas). The sound is much like the transmission whine that you hear in 1st gear on the 6MT. It crescendos with throttle application and decrescendos as you release the throttle. My guess is that it's just the new sound of pressurized fluid flowing through the lines and cooler. My concern would be that it's a pissed off oil pump.

Thoughts? Anyone with similar sounds post-cooler install?

Can you record it? Could an oil line be rubbing against something?

I'll give recording it a shot, but I think it will be too subtle for crappy iPhone recording. Definitely not lines rubbing anything. The sound is perfectly reproducible and continuous with every throttle application. It's almost identical to the transmission whine (ie, whiiiiiIIIIIRRRRRRRIIIIIIIiiiiiiirrrrrrrr as throttle is applied for the first half and then released and the revs drop on the second half of the 'sound').

To be completely honest I don't have a very clear idea from your description as to what the sound is like. Is it a rattling noise? Is it a sound like air/fluid running through a pipe? I've never been able to "hear" an oil cooler before, especially from inside the car when all the major components are out in front of the engine.

How much fluid did you add? Did you double check your engine oil after the install was complete?

Where did you purchase your sleeve nut and oil cooler filter adapter/spacer? I have seen on these cars where the sleeve nut is just a tad bit too long. We actually trim ours down. If the sleeve nut is too long may not leak oil but it does prevent a perfectly flush fitment and can cause the spacer to rattle a bit...You want to fix this ASAP as it may not leak oil today but it might in the future.

Also, some people have mentioned that they can hear the flow valve/ball rattle in some cases. This would amplify as the RPM increases.

The system took just under 6 quarts of oil when I refilled it. I've checked the levels numerous times over the past four days and it's rock steady.

As for the noise, it's not a rattle, vibration, or buzz. It's a whirring sound almost identical to the sound of a loaded transmission driving in low gear. At low rpm (idle), I can't hear it at all. With some application of throttle and the revs coming up, I can hear it build and become slightly higher pitched. Similarly, it decreases in amplitude and pitch as the revs drop back to idle where the sound becomes inaudible again.

I'm using the same Mocal sandwich adapter (with included sleeve nut) that Modshack used with the exception of a 200F thermostat. The sandwich adapter has a nice, flush connection both with the car-sdie and the oil filter on the other side.

On my way downstairs to record it now.

Does the sound go away when you reach operating temperature?

I have the same noise after installing my 25-row Setrab. I'm pretty sure it's due to the added oil running through the thermostatic plate/oil lines/cooler. It definitely sounds like a medium/high pitched whining noise as opposed to a clunking/rattling.

And no it doesn't go away after reaching operating temps. It's actually audible from inside the cabin with the winows up.

Mine is quiet, I wonder if you trapped air in the lines?

I've taken some videos and they're uploading to YouTube. Should be viewable in just a bit. If anything, I notice the sound more after the engine temps come up. The cooler is definitely getting flow and 'working' as the engine temps are about 20F lower in any given situation now. You may also notice I have the Stillen power steering cooler installed. There is no association with steering input, so the steering cooler isn't related.

I'm wondering if I'm crazy or what. The sound seems to be more from the block/valvetrain than from anywhere near the cooler or lower by the oil pan. You'll notice it on the decel as the revs drop below 2k towards idle (but audible throughout the range).

I did have the engine oil on the high side, so I just removed about 300ml and it's just below the H hole now on the dipstick. No change in sounds though.

Hopefully this is a just case of hypochondria given my reading about all the oil-cooler debacles people have had.

In Car:


Outside car using a torque wrench to depress the accelerator!:

Vids up

Here is a reference to what I guess is the same noise:
http://www.the370z.com/engine-drivet...tml#post221233

Hmm. It must just be a weird resonance associated with the sandwhich plate. Huh. Go figure.

My mocal plate doesnt make any noise

Next step is my stethoscope on Saturday. Saw some hits on Google about oil filters making the noise. I've been using K&Ns and never heard this before. Just ordered some PureOnes (Purolator). We shall see.