New valve cover gasket, now valvetrain noise at idle
 

First things first it's a 1995 with a BEGI 4.2 kit. 93,000 original miles, PO said the timing belt/tensioners/water pump were all done at 75K.

I took my valve cover off to powder coat it and saw the valve cover gasket was thrashed so I was going to replace it.

I took the baffles out of the valve cover, pulled out the PCV grommet, and removed all of the old gasket material on the baffles and any remaining RTV in the "leak spots" on the head. I cleaned the valve cover in warm soapy water, and baked it for an hour to get rid of the oil residues and water.

I coated it, put the baffles back in using Indian Head shellac on all of the gasketed surfaces and replaced the PCV grommet because the old one was as hard as a rock. The cams were really clean with no signs of wear. I made sure to wipe the oil off of all of the gasket surfaces as well as the high pressure oil passage ways.

One thing that I thought was odd is that between the two plug holes towards the cams, the little rubber thing that went between the seals didn't fit over part of the baffle so it was all stretched to go around it.

I reassembled everything, topped it off with oil and started it.
There's valvetrain noise at idle, but not when above idle. The useless oil pressure gauge on the dash reads where it was before so it's got oil pressure, I'm just not sure how much.

What could be the problem?

Change your oil.

I planned on it, it's about due. I'm going to pull the valve cover again just to double check everything. Is there some magic trick to pull it without unbolting the coilpack bracket?

If you about due for an oil change that explains a lot. I get valve train noise at idle on my NA heads when the oil has over 2000 miles on it.

You have to remove the 2 upper 12mm bolts that hold it to the valve cover, that's pretty simple. You can leave the lower one in place.

They're a bitch to get to and the PO rounded the driver's side one damn near totally. Must get COPs.

What oil's good for a boosted 1.8? PO had Mobil Clean 7500 10w30 in it.

Anybody run a filter relocator with a huge filter like a FL1A on it?

Gear wrenches work well on those bolts but if one is rounded off and you can't turn it maybe you can get away with removing just the lower bolt from the head and taking the coil pack off with the valve cover. That bolt is a bitch to get to also.


I would go with a synthetic oil to handle the additional heat.

10w30 or 5w30?

I've been running some 0w30 or 0w40. i forget which. i figure it'll get up into the needed areas of the motor and turbo quicker.

Do a search for HLA flush on here or miata.net. That could be a more long term solution than every 3000 miles.

That really works? What type of ATF? Dextron Mercon 3?

I used a large dose of seafoam, did it for me.

How long did you run the Seafoam? Half can or what?

Search Miata.net for "twisty flush", there is good article that documents how to do this ATF flush. I had pretty good luck with a twisty flush last year on my 1990, it significantly reduced but did not eliminate the HLA noise. If you want to take the time, you can remove, disassemble, clean and re-assemble all 16 HLAs. The design of the HLAs make it difficult for oil to "circulate" through them..and once they get gunked up it is very difficult to get the innards completely clean without disassembly. There is a good write-up on Miata.net by someone that did this project. For me, the twisty flush gets me 80% there with a fraction of the work.

Half a can. Just drove around the block a couple of time to get it to move around. Flushed, refilled, and they quieted down.

I think Chad told me it takes the engine like 1 minute to circulate all the oil in the engine so I figured I wouldn't drive around for more then 10 min.

I'll do that, then the twisty flush :)

Try reading this article http://www.miata.net/garage/hla/cleaning.html before you try the seafoam or twistyflush. The author describes a method of running/stopping the engine at least 8 times after cycling the flush through the engine. The reason for "cycling" the engine is that any given time the engine is stopped, only 2 HLAs are "theoretically" in a position to expose the oil entry hole to the flush. Noisy HLAs are caused by the fact the old crappy oil doesn't get flushed from the lifter, so trying this additional step can't hurt. I wasn't aware of this procedure when I did my flush last year.

YMMV,

Mitch