4evertopless

I Have done an engine flush (With solvents) on a few cars I bought high mileage used ( 70k~ miles) I change the oil to a cheap dino, add flush, run for a half hour (Idle) Then change the oil to my desired synthetic.


At 500 miles, I change it again, to rid any residual solvents.


This helped some valve train noise in my 97 mazda miata significantly.

2007 Zx-10

If you change the oil regularly, such procedures should not be necessary. Anyway, I think we've established that sludge/varnish does not cause valve train clatter at start-up in S2000s, it's normal.

azap1

YES i have that same noise too. It is normal, i've had it since 40K and now im at 72K mi. It goes away once the engine warms up. but i have noticed with every new oil change it goes away while the oil is still new

terahertz

try another oil. i had that with mobil 1, but have never heard it again after switching to amsoil. when i couldn't get amsoil once, i put m1 back in, and that's when i noticed it.

EOE

If it's Buzzing, Chatter that sounds exactly like loose heat shield. That's your timing chain tensioner. Way to check is have some one start the car up for you. Be right in front of the motor, you'll know right away weather it's normal or not.

2007 Zx-10

No buzzing, just a chatter that disappears after about a minute with something like Synpower or Amsoil

dimi

I wouldn't really worry about it. When I start my car, it is so loud with all kinds of noises making an appearance. 2 mins in its dead quiet. I don't know why Honda made a cold start rev to 2000+ rpm. I think that is when it should be revved the lowest, but either way.

Also an S2000 has a very noisy valve train.

INDYMAC

Like I said earlier, just start using MMO in your fuel and you'll be good to go. No more start-up noises from the valvetrain.

2007 Zx-10

And, again, at the risk of adding a solvent to your oil. Have you run a UOA with and without MMO?

INDYMAC

Yes I have, as I mentioned previously. There are no problems at all.

MMO has probably been around longer than any other oil additive. In fact, the company actually recommends you add it to the oil and fuel. It's probably the universal "go to" fix for stuck lifters when all else fails by mechanics.

There are already much stronger solvents added to store bought fuel than you would ever find in MMO. So, I'm confused about what your concern with solvents in MMO are. Solvents aren't what you're looking for from MMO to help with the noise, although it will help an already clean fuel system stay clean. It's the lubricious characteristics of MMO that seem to be quieting the valvetrain. I think it leaves a light oil film of lubricant on the valves and fuel injector heads, but I have not torn apart and investigated. Other UCL's might work too, but I have not tried them all. Some fuel additives that don't seem to help with noise are FP+, RLI fuel injector cleaner, and techron concentrate.

Some engine oils I've tried in the past have worked all by themselves too. But their formulas have changed and aren't available as viable options anymore. That's what led me to MMO as a solution. If you are looking for an oil that might take care of the noise without using fuel additives, try an AMSOIL product. I think their ATM 10W-30 would be a good place to start. I'm using LE 8130 right now in another vehicle and that oil has to be one of the quietest running oils I've ever used in a engine. You can't even hear the pistons firing through the headers anymore. I'll eventually move the LE8130 into my S2000, but it will be a couple of more years as I use up some older oil stash first.