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.

I am using both Mocal and K&N http://img444.imageshack.us/img444/2483/dsc3270h.jpg

Uploaded with ImageShack.us

I like your lines being above the sway. But it's time for new tie-rods!

Here's a shot of my line run.

mine started rusting about 10 days after owning the car, now much you can do about it in the north east :shakes head:

Sand them down and spray with a high temp clear enamel.

I still have the same sound your describing.

I see that you also installed the upgraded power steering cooler from Stillin. I do also have the same cooler installed. I installed the oil cooler and the power steering cooler at the same time.
I got rid of the clicking sound that was coming from the sandwich plate by replacing it with the Mocal sandwich plate.

About the other sound. it's obvious that other engine oil cooled cars don't have the sound we have. my only novice explanation is the sound mite be normal and the bigger PS cooler just magnified the sound of the normal operation of the power steering, Or there mite be a stress on the Power steering it's self from the added cooler.

i think it sounds cool either way.

doesnt our cars take just under 6 qts of oil stock? So with an oil cooler I think you should be putting in another qt atleast depending on how big the cooler is. So are you sure the cooler is filled with oil? Maybe the plate isnt opening like it should. Modshack might be better able to add to this issue.

You're off by a quart. Stock takes just under 5 quarts. With a cooler you're closer to 6. I think I used about 5.5qts with mine which seems right visually.

Stock oil capacity is 5 1/8 quarts.

Any time I've done 5 1/8, I ended up having to siphon some out. Perhaps since I use the slightly smaller K&N filters.

Interesting. I use the HP1008 (the small one) and 5 1/8 is a perfect fill.

I have a 25R cooler, I think I ended up using 6.2 quarts

Which way did you install it (fittings up or down)? I have my fittings down. I wonder if I have an air-lock or the dipstick isn't accurate with that orientation. I asked Modshack about the orientation question and he thought it was a non-issue. With the fittings down, would the dipstick read 'full' and then the actual circulating level be too low when the system is pressurized and flowing (ie the cooler fully fills and the oil pan level is too low)?

Assuming the oil cooler is mounted higher than the oil pan the oil will run out of the cooler when the car is off, resulting in innaccurate dipstick readings, no?

What size is your cooler? With the lines and cooler only 5.5 quarts seems really low.

It's a 24 row Tru-Cool that Modshack used. It's hard to guestimate, but I wouldn't think the cooler is much taller than the oil level in the pan with the engine off. I had almost 6 quarts in there last night and I was above the H dot when pretty hot. I took off 300cc (~1/3 quart) and now it's just under the H dot when stone cold.

I just don't know any good way to check the oil level with the cooler installed to test the possibility of inaccurate dipsticks with the fittings down. I suppose I could unmount the cooler and hang it down by the ground. Then a dipstick reading should be accurate with the cooler full.

I thought you could run up to ~1/2 a qt over full without issues.

I'd put my money on this being the issue....Oil coolers don't make noise, Power steering pumps do....Much like you describe, especially when low on fluid.

No....The Bypass system retains oil in the cooler. Whenever I've changed oil, I always get about a quart out of the cooler and lines...

http://images53.fotki.com/v439/photo...MG_2379-vi.jpg

Forgot about the bypass!

Modshack to the rescue.

You should be on the forum payroll, you know. :tup:

Modshack, you have a Starbucks gift card being emailed to you as soon as I figure out how to do it. You've been incredibly helpful with my whole install. If the bypass system retains the oil, then the dipstick will still be accurate.

So why would my PS pump make noise if I've bled the system? Just the added strain of pumping fluid through a 9-row cooler rather than a smooth tube with fins attached (the stock POS)? I'm hoping the last two sentences in the attached service manual clipping are the explanation. I followed the priming instructions in the service manual (turning lock to lock) and there aren't any more air bubbles coming out. It took about a quart to refill the PS system. What makes no sense is that the manual says the system takes 1 1/8 quarts and I've now added a new, somewhat larger cooler. Unless there is some retained fluid from the drain, I don't know why I only fit 1 quart. Annoying...

he said he wanted a steak house gift card for his whole family. lol. Well Im glad to hear its not an oil cooler problem as I will be doing mine here shortlly now that Im back from my training.

We can't reward Modshack too much as he's defecting, and that shouldn't be encouraged with gifts.

Functionally the coolers have been working great. It's simply the issue of a new sound after installing the oil and steering coolers. The improvement in oil temps is fantastic though. 95F ambient yesterday and my temps while sitting in traffic after a sporty highway jaunt never went over 215F.

LOL...send Money!

I like coffee....Contributions appreciated!

You guys can continue to abuse me while I'm still here.....But there are sharks circling around my car as we speak!

Try it again...Whenever I've purged PS systems I've had both wheels off the ground and cycled things left and right several times with no load on them...