Hydraulic Lash Adjusters, again...

I parked my '89 626 in April when I put my Supra on the road. I now have a job where I put a lot of miles on a car, and the Supra isn't up to it, and I ain't using my Scion for this!

When I started the car after sitting, the clacking from the HLA that's 'bad' was horrendous!!! You could hear it quite a ways away from the car. It was due for an oil change, but I needed tha car. I bought a new valve cover gasket and a set of 4 HLA's, since the place that had them in stock didn't sell them separately...all together, $50.

I also picked up a quart of Marvel Mystery Oil and Castrol Syntec 5W-30. Since I needed tha car that day I added a half quart of each. (This was a mistake since it overfilled the crankcase and I could smell burning oil for about 200 miles.) The clacking was very faint most of the time, with an occasional increase in volume every other start. It finally subsided to a tolerable level.

Now the car had been used for a 20 mile one way commute to work, and a LOT of 2-5 mile trips around town. Now it gets run 4 hours a day with two brief turn offs, and an average speed of 30 MPH (anywhere from 15 MPH to

55 MPH.)

It was due for a change, so I changed the oil. I put in 3.5 quarts of Castrol GTX High Mileage, 10W-30, and a half quart of MMO. Level on the dipstick is where it should be.

The car runs as quiet as new! It hasn't done the clacking thing since the oil change. So...do I open up the valve cover and have a look, or do I just count my blessings and continue to drive?! Everything seems just fine after two days.

crossing to Toyota cause there are some decent people there, too...

Reply to
Hachiroku
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...if it aint't broke....

Reply to
Bob H

You fixed it Hachi! With out pulling a wrench! Nice work! I think you can use that MMO as a laxative as well.

Reply to
user

If the hydraulic lash adjusters are actually the source of the noise, then they were probably noisy because the car sat for so long. My guess is that the next time you park it for any length of time, the noise will return and you will have to put up with the noise for a day or two. You can probably get away with this for a while, but the noise is probably due to excess valve lash, which can have a pounding and wearing effect.

Reply to
Ray O

I'm going to start something here. Save your money, use kerosene instead of the MMO.

The clacking is because you got a little piece of crud in the oil supply pin-hole that keeps the lash under control. MMO has a lot of cleaning stuff in it and either dissolved the crud or loosened it up enough so it would flow out. Kerosene will do the same thing, use about a quart but don't drive the car. Warm the engine up and add a quart of kerosene with the engine running. Let it run at idle until the clacking goes away. Drain the oil and refill with good oil and change the filter.

I had a '64 Corvair Monza that started clacking like mad. My dad suggested it and it worked in minutes.

Jack

Reply to
Must be Me

Hey, Ray, it started before I parked the car for the summer, and was getting regular use, albeit short trips of 2-8 miles or so, lots of cold starts, etc. According to what I have seen, this is the worse thing you can do with this valvetrain...

But even trips to VT and NH sometimes wouldn't stop the noise. When I parked the car it was pretty bad, so I was going to take the cover off and have a look, but since I have had to press the car back into service, I didn't get the chance.

So, I guess as long as it 'ain't broke...'

Reply to
Hachiroku

Um...I think I'll pass on that one, P@B...

Reply to
Hachiroku

I hate to be the bearer of bad news, but I think it's broke, and the MMO hid the symptoms without curing the root ailment. :-(

Reply to
Ray O

I think you fixed it. MMO is the kind way to attempt to free the check valve and spring in the lifter. If you really want to go to extremes, use Berrymans B-12. It should be available at mass merchandisers. It is marketed as a carburetor cleaner. It's ingredients contain toluene. It is a volatile chemical that will dissolve sludge and varnish. Use only one can in the crankcase for problem lifters. If that won't do it, disassembly and cleaning, or replacement of the lifter is required. You are trying to free up the check valve spring and plate in the lifter. It does not take too much thick oil deposits from interfering with the intent of design. If you ever take a lifter apart you will see what I mean.

Reply to
user

So far, so good!

Reply to
Hachiroku

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