what's "hla clatter" ???

[greg_atlanta]

I've heard the term before as it applies to older engines which get noisy. What does it mean?

I'm hearing a few noises I don't like in my '92 Q. It's very subtle, and timing chain and guides were replaced at 131K by dealer (at 181K now).

Running full synthetic 10W-30 + half a can of BG MOA/111 right now.

[DAEDALUS]

I'm not real clear on this, but I'll give it a shot. HLA is hydraulic lash adjuster. Before hydraulic valvetrains, many cars had threaded studs with locknut pairs that had to be adjusted periodically. Hydraulic adjusters need less maintenance (self adjusting height, based on temp I think), but I assume they evenutually wear beyond the adjustment range. A larger gap between the HLA and the rocker leads to clatter, since the rockers are striking with less smoothness and more force. Also, I think they need to be bled if air gets inside them during disassembly. On my '84 Honda Nighthawk there were things called "tappets" which I think are the same thing, but I'm not certain.

[Q45tech]

Oil pressure rises from 14 psi minimum at isle to over 60 pai at 3,000 rpm and gets limited to max of 87-90 at any rpm above this, so the force from the HLA is a function of rpm up to 3,000.

There is a tiny oil entrance hole whose diameter can change with varnish or air from draining back of oil through filter [zero pressure] can delay the proper pump up and thus let the cam followers flop around making noise when they hit the non pumped up HLA....creating wear on the follower/cam and HLA.

Once it starts it is very very very difficult to correct successfully as even BG Quick Clean takes multiple applications and can do nothing about the wear you allowed to occur by improper oil /filter changes.

It usually doesn't make economic sense to pull the heads and change 16 x2 = 32 HLA as the valve seats, valves, springs, cams, & cam followers are also worn............much less expensive to change the whole head but finding a good one is the challenge!At retail the new parts alone would be $3200 plus $2,800 in labor to install them CORRECTLY..........never seen a "valve job done correctly [to anywhere close to factory precision] at any dealer they just don't have the equipment to build racing engines!

By the way the cams are $250 x 4 or $1,000 alone and I assumed that they were still good enough in the above $6,000 calculation

[landtodd]

Geez, I thought I would coast through another week, but that does it -- I'm changing my oil this weekend.

Due first to repair/replacement costs, and second to the extraordinarily long life of the motor, more than many cars, the Q rewards persistent good maintenance.

Thanks, Dennis.

[landtodd]

Try a car without hydraulic valve-lash adjustment. Like little British cars of the 60s-80s. You had to adjust all 8 valves with a feeler gauge, motor HOT (at least with the evergreen BMC 1500). Seemed like you had to do it once an hour (I exagerate).

I don't think there's anything to do about a little HLA noise except an annual oil flush and frequent changes. There's not enough oil flow -through- them for the solvents to remove much vanish. Economics dictates that for most people, it's one of those things you live with until it dies. Not dangerous or a sign of immediate impending doom, just the sign of an older motor.

[greg_atlanta]

Thanks everybody... I think that may explain it. I only hear it at idle. If I rev the engine I can't hear it... not meaning it's not there, but the noise of the engine drowns it out??

All the belts look fine and were recently tightened, and there's no play in the fan, so I'm almost certain the noise is coming from inside the engine. Kind of a clack-clack-clack.... almost sounds like a diesel.

I can barely hear it from the driver's seat, only if the climate control and stereo are off.

I just used the new Mobil 1 formulation (10W-30) with last oil change about 3 weeks ago and engine still runs great. Wonder if the oil has something to do with it? I think I'll switch back to Valvoline Durablend (syn blend) or conventional and just change every 2 months regardless of mileage.

I haven't use Marvel Mystery Oil in a while... maybe that will help??

May drop by T-3 next week just to confirm it's not something simple. I'm definitely not ready to start pulling the engine apart for $2000++++. Think it's time to go into minimal mainteance mode and hope I can get another 2 years & 20-30K miles without too much drama. It's paid for!!!

[greg_atlanta]

Oh... on prior oil changes I was using Valvoline full synthetic 10W-30 + half a can of BG MOA/111.

I've never used BG Quick Clean before, so maybe now's the time?

(Still revs very smooth and has plenty of power)

[landtodd]

Think it's time to go into minimal mainteance mode and hope I can get another 2 years & 20-30K miles without too much drama. It's paid for!!!

I like that "paid for" part. That's why I never flinch at the occassional $100 here and there -- beats heck out of $400 a month. Every month. Then again, I haven't spent anything on it since the plenum went back on. Time for tires and a JWT ECU.

Old cars are so much more fun.

[greg_atlanta]

And.... I should mention that I was on the road for 5-6 hours/340 miles Dec. 24 and same trip again on Dec. 25, non-stop, averaging 80-85 mph. Didn't notice it until I got back.

I think my car is sick of Xmas too!!

[greg_atlanta]

Old cars are so much more fun.

True.... but they're no fun when you're trying to get out of credit card DEBT!!!

I think my next car will be a 4-cylinder/5-speed Altima or Accord or RSX or Civic on a 3 year lease if I can do a minimal downpayment and keep monthly payment around $300/mo.

But frankly I should stop worrying about my next car and enjoy what's left of The Mothership!! (though I may need to rename her the Millenium Falcon).

:help

[landtodd]

6 hrs/day for 2 days? Yuck -- I know why you're sick of road trips. No matter how much I like a car, I have about a three-hour tollerance for being on the road.

You must have your vibration problems licked. Working on mine now -- an hour on the interstate is unpleasantly far for me and the Q just now.

[greg_atlanta]

You must have your vibration problems licked. Working on mine now -- an hour on the interstate is unpleasantly far for me and the Q just now.

If my car bites the dust I'll sell you my brand new driveshaft!!!

[landtodd]

If my car bites the dust I'll sell you my brand new driveshaft!!!

Let's see. What can I do to hasten her demise? (Purely kidding, but I would be interested.)

[greg_atlanta]

Let's see. What can I do to hasten her demise? (Purely kidding, but I would be interested.)

Give me $8K and you can hasten all you want!!

Frankly, she needs a bath (and good drenching of silicone on the squeaky but in-spec driver's side upper link). That always makes her feel better. Or at least makes me feel better about her. :cuddle

[PalmerWMD]

HLA Clatter on my Q before this cream one:

Fairly severe on cold starts sounde like a diesel.

Fixed via 1 to 2 week oil changes w/ Valvoline Durablend with .75 quarts ATF idling for 45 minutes right before oil change.

Also used some MMO during the week, prior to oil change.

Did this 5 times, short consecutive oil changes w/ method outlined above--> fixed it.

Fred...:thumbup

[greg_atlanta]

I think a good cleaning routine should do the trick!

Dropped by T-3 and Dennis & Byron listened and said it sounded normal. It probably falls under "HLA clatter" buty nobody has figured out exactly what it is. Nice to know it doesn't put the engine on death row.

I'll start with MMO (marvel mystery oil) and then use BG Quick Clean and see if it improves.

[forecast]

When I rebuilt my Q engine I paid a lot of attention to the lifters since I had heard horror stories about lifter clatter.

From my examination I determined (of couse I could be wrong)

Imagine two guys holding a ladder over thier heads. One guy is the valve stem and the other the valve lifter. Suddenly a giant fist drops out the sky and hits the ladder (rocker arm) in the middle. One or both of the guys goes down. In the engine it's the valve stem that drops, opening a valve down below, letting gases rush where they need to rush.

Suddenly the fist disappears, actaully it raises up a few feet. The stem guy can stand back up! in fact he comes up so quickly (driven by both a spring and gasses in the cylinder) that ladder keeps going up after he stops. In this condition the next time the fist (cam on the cam shaft) comes down the ladder thunk against the valve stem guy and cause a tiny bit of wear. Over a few million reps the valve stems busted.

Worse, the valve stem isn't a constant length. As it gets hot it longer.

Enter the valve lifter hero. He is resistant to the cam and won't go down except under very high pressure. When the cam rolls away he keeps the rocker arm tight against the valve stem. When the valve stem is cold, he lifts a little higher, to always keep the rocker arm in contact with both the valve stem and the cam.

How does he do this. Different cars do it differently. Some cars have fixed adjusters (Honda Accord)

but the Q has hydrulic lifters. This a two piece telescoping unit. At it's full height it will actually force the valve open a hair even if the cam is not trying to lift a valve. The unit also rides on a bubble of oil. The Valve lifter can rise up in it's seat a hair (not much though, the act of moving up relases the pressure that lifted it so I imagine it floats a 10th of an inch above it's seat in most cases. Under high pressure situations (long valve stem) the telescoping action in the valve lifter colapses by venting oil from an internal high pressure oil chamber. When the situation cools down, the valve re-extends by an internal spring pressue and the lifter redraws oil into the high pressure chamber back through a one way check valve.

If for some reason the lifter loses oil pressure it may draw some air into the high pressure chamber. From then on the valve lifer will never work right again - it collapses too easily and rocker arm (the ladder) slaps against the valve stem, cam shaft or valve lifter. That slapping noise sounds like a loud tick

Other failures of the valve lifter are - it seizes in it's seat and doesn't get any cushioning from an oil pocket. The telescoping unit seizes (loud cold engine, but quiet hot). Or the high pressure chamber won't hold pressure, the unit collapses under any load (this isn't very loud by limits valve opening since the lifter is moving not the valve.

dan