Cause of ticking

[maldotcom2]

So we're all aware of the Ecotec tick. I'm wondering if MACE has worked this one out, it has to be valve train related as my engine ticked from the get-go after a rebuild, which rules out bearings or worn components. This was very disappointing as the noise was a key motivator for a rebuild.

My thoughts are either not enough preload on the lifter due to short pushrods, or perhaps deteriorated or poor quality lifters. Are MACE lifters a solution to this? I believe MACE would have some insight to this engine specific question.

[MACE]

Lifter crush/preload would be the main reason for the ticking (assuming that the ticking noise isn't from the extractors). Find out what it is at the moment and get back to us.

Cheers,
Steve

[DevilDRake]

To give you little insight maldotcom2, i got my lifters changed and it didn't stock the ticking. I've talked with Steve about this and he also said to me you could increase lifter crush by either longer pushrods or higher ratio roller rockers.

I'll be getting roller rockers soon (from 1.6 to 1.75) and I'll let you know if it stops it.

OFF-T: I haven't got around to an oil pressure check either Steve.

[Not_An_Abba_Fan]

Does it tick with the belt off? The tensioner is known for ticking as well.

[maldotcom2]

I've replaced the lifters twice to no avail, once before the engine rebuild. So unless dodgy lifters are very common, it's not failing lifters. Ticks with roller rockers or without. It is not the timing chain as i'm running a double row with no tensioner and no balance shaft. Replaced idler pulleys and tensioner. I'm sure i've tried it without the belt but i'll try again.

The other thing i'm thinking is PCV valve. The tick isn't fast enough to be coming from every lifter, or every injector, so perhaps something to do with the rotation of the crank and associated pressures.

This ticking is what I think about in the shower, on the toilet, and before I go to sleep.

[db_notso]

... right<?

brain scratch....

on rebuild was ALL individual journals on crank measured and given bearings to suit? if a generic set was fitted from a one or two off measurement skip to below (taking load off cylinder)

oil pressure check would be one (if light not on prbs ok)....

oil should not be anything redicuously thin, and noise should not change with temp(not go away if does live with it ts not worth chasing)....

if holding revs at say, 1500rpm removes noise likely an oil pressure OR lifter problem (higher pressure relief valve in oil pump will fix this)

taking load off cylinder;
if noise occurs at idle, unplug injectors one by one to take "load" off each cylinder eliminating internal noise(gudgeon pin on piston etc)if noise goes away concentrate on that cylinder..

apart from that... blancer seperated(at internal (behind rubber)? and clanging about, rare but happens....

a stethoscope would be a good investment for you maybe especially w/out a balance shaft as noise will echo more throughput motor, just check front and rear left and right and see where noise is loudest...

im busy as atm but if you answer these questions mace(steve?) or other should be able to help sort you out~!

[maldotcom2]

All journals (mains and big end) were within spec for STD bearings, verified by a dummy assembly with plastigauge. Small end bearings were replaced and reamed to size. But I will try the injector idea, thanks for that!

Oils i've tried are 10W 40, 10W 50, 15W 60, 20W 60. I've got an oil pressure gauge, pressures at idle are 50PSI at the lowest, and normally 70 PSI cruising. The ticking exists through the rev range, but higher up it is too fast to notice. Very noticeable below 3000 RPM.

I used a brand new powerbond balancer and had the bottom end balanced with that on.

I'll try the injector idea, and with the belt off. I'll post back with results. Thanks guys!

BTW Steve thanks for the great service with those 130lb springs I rang about. The engine seems to be running better than with the 105lb.

[maldotcom2]

Ok it makes the same noise without the belt, and disconnecting an injector just slowed the ticking due to the idle dropping slightly. I bought a stethoscope but I can hear the noise anywhere on the engine, it is at its loudest up near the manifold.

[darcycammo]

This is the same problem that i had tried heaps of things in the end it made it worse that's why im rebuilding another engine to put in.

[Not_An_Abba_Fan]

It wouldn't be injector tick echoing in the cavernous plenum would it?

[immortality]

I wouldn't think the injector ticking would be that bad in a ecotec (like the earlier Buick 3800 V6) because of the sequential injection. Which lifters are you running now and how much pre-load have you got?

[maldotcom2]

Well see if it was something that EVERY ecotec did, I'd just have to live with it or sell the car. But some don't, so it cant be simply a design characteristic. I can't help but think, is there a way I can temporarily disable the PCV and just vent it to see if that is ticking?

[maldotcom2]

I'm using "Nason" brand lifters. Apparently an aussie company, cost me about $150 for the set. I dont know how to determine preload, but i'm using the Yella Terra ultralite 1.6 RR's with the pushrods and pedestals supplied.

[immortality]

how much have you skimmed the heads and decked the block? What thickness head gasket have you used? Ideally you would use a adjustable push rod to check the length required. Maybe contact the lifters supplier and ask what the recommended pre-load is suppose to be with there product.

What springs/retainers are you using? Have you checked for clearance between the rocker arm and spring retainer when the valve is on the seat?

[MACE]

If you're using Nason lifter then they're likely made in Asia.

Have you had a chance to inspect lifter crush?

Cheers,
Steve

[maldotcom2]

Skimming of the deck and heads was very minimal. I don't remember exact figures, but it was purely for an even surface, not to gain comp. Head gaskets are ACL monotorque.

Springs and retainers are 130 lb. Crow and LS1 retainers from MACE.

Yes I have a suspicion they may just be crap lifters. By inspect lifter crush do you mean measure it with a dial gauge? I haven't done that. Just to clarify, there is no "Zero lash plus half turn" business with this engines is there? Just bolt them down?

I'll rule out cracked exhaust manifold before I start diving into new internals. *again*.

[maldotcom2]

Here's a movie I made of the noise. It's most distinct under the car, as it avoids the rest of the engine noise.

MVI 0028 - YouTube

[DevilDRake]

Sounds like my ticking, just mines not as loud.. And you can hear it inside the car til about 3000+rpm and then it disapears as it's ticking too fast or the exhaust over goes the sound..

I dunno if yours is the same, but mine coming from the rear left of my engine, but everyone still reckons it's my injectors.. I thought it was a lifter straight up - which i hope not, but i'll try putting more crush on them as the pressure is fine..

edit: And mine didn't tick before i got the cam/lifters etc all done.. Well it sort of did, but it was a tiny tinggy tick all the ecotecs have, right now like yours is blown out of proportion lol.

[maldotcom2]

I found something out today, I stuck it in 5th at 50km/h, obviously engine speed dropped to about 800 RPM but no ticking at all! It had never been quieter. Why does this occur, when it does tick at idle 800 RPM? Does the extra labour on the engine tighten up the valve train?

[MACE]

I'm pegging it's got to do with the exhaust, assuming that the lifter crush is in spec (?)

Ecotech/l67 engine noise(valve train) magnified by extractors?

[maldotcom2]

Ok I just shot 100 PSI up the exhaust pipe and got under the car with soapy water. I found some leaks around the flanges which I have repaired with new gaskets, bolts and high temp silicone. The noise is still identical so it wasn't that. MACE, if I buy your CROW lifters do you have the specs for preload so I can determine whether or not I need longer/shorter pushrods?

Does anyone else have tuned length extractors? I'm wondering if this is amplified valve noise.

[MACE]

"Ok I just shot 100 PSI up the exhaust pipe and got under the car with soapy water. I found some leaks around the flanges which I have repaired with new gaskets, bolts and high temp silicone. The noise is still identical so it wasn't that. MACE, if I buy your CROW lifters do you have the specs for preload so I can determine whether or not I need longer/shorter pushrods?"
Yes that's not a problem

"Does anyone else have tuned length extractors? I'm wondering if this is amplified valve noise"
Before changing lifters I would try somehow physically mount this material to each header (or use exhaust wrap to a lesser degree)

ACL Race Series Heat Shield Material

This will dampen help in dampening the sound.

[maldotcom2]

Thanks MACE,

I'm pretty skeptical about sound deadening. That would be a band-aid fix. I'll probably have to take the plunge and get the lifters (yes pun). FYI I noticed while running the motor with the rocker covers off that there was bugger all oil coming out of the rockers. Some rockers had no oil after 10 minutes of running.

To the guys suggesting it's injector tick, I could try unplugging the Cam Angle Sensor and see if that changes it to a slower tick. My understanding is this sensor controls the sequential injection while CAS controls ignition? If my thinking is correct it should then pulse all injectors at once like the buick.

[MACE]

Thanks MACE,

I'm pretty skeptical about sound deadening. That would be a band-aid fix.

If there is an underlying mechanical problem then I completely agree with what you're saying.

However, if you had the same sound before the build, what could it be? I guess you can try changing the lifters and checking the injectors

Keep us posted

[maldotcom2]

Ok I put in a new set of Crow lifters and nothing has changed, when I first tightened up the rockers with the new lifters I counted 2 full turns from zero lash to hand tight (25 Nm?). I'm not entirely sure what the torque spec is on those YT cap screws but either way i'm looking at around 2 turns of preload at the moment. Too much?

I've taken it for a drive to run them in a little, i'll recheck the preload once it all cools and the lifters bleed off.