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New Heads, New gaskets, New NOISE!?!


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Been driving my car for about a week after slapping on new heads and new gaskets. Car drives great except, I'm starting to notice a "noise" coming from the passenger side head. Really hard to tell where exactly it's coming from, from inside the car it sounds like the pass side. When I open the hood, I cannot hear it as much, but there is a slight "knocking" coming from the passenger-side cam cover.

 

From inside it sounds a bit like a diesel VW Rabbit engine; a very low, hollow, knocking or drumming noise. It's really prominent during hard accelleration (freeway onramps) between 25 & 3500 RPM. Even when I say "prominent", I still have to strain to hear it. It is there though, I've been driving all week without my stereo on so I could hear what my engine is doing. I've become hyper-sensitive to noises, and this one is developing.

 

Gauges all read norm, get 85psi driving and 45psi at stop lights, temps are okay.

 

So again, if I had to discribe the noise, it sounds like a Diesel Rabbit (just a little bit).

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You might want to get yourself a mechanics stethoscope, great diagnostic tool.

 

On listening: I almost always drive the first and last few miles of my commute with the radio off, I like to catch new noises before they become big problems.

 

Gary

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You might want to get yourself a mechanics stethoscope, great diagnostic tool.

 

On listening: I almost always drive the first and last few miles of my commute with the radio off, I like to catch new noises before they become big problems.

 

Gary

 

If this makes any sense; just before leaving work I started the car and listened (it's getting slightly worse with each cold start). It's definately coming from the passenger side head. In fact while the engine was idling I pulled the oil filler cap and, *Whoa!* sounds like some demonic breeding-pit in there. Loud, gurgle-knocking noises.

Plus it's "Pushing" air pressure out of the filler neck, is this normal? I would think it'd be sucking because of vacuum.

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is a cam follower not seated right?

pull a valve cover off and have a look. look at all the cam followers, cam lobes and rotate the engine by hand to make sure everything appears to be workign properly.

 

a compression test on that side would be interesting at this point.

 

are you familiar with the HLA's ticking? is it similar to that? on rebuilds and head jobs the HLA's can be problematic to get back to working order.

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is a cam follower not seated right?

pull a valve cover off and have a look. look at all the cam followers, cam lobes and rotate the engine by hand to make sure everything appears to be workign properly.

 

a compression test on that side would be interesting at this point.

 

are you familiar with the HLA's ticking? is it similar to that? on rebuilds and head jobs the HLA's can be problematic to get back to working order.

 

I double checked everything when the enginne went back together, rotating it periodically. I'll pull the cover anyway and have a look this weekend.

 

I'm not familiar with HLA's or thieir noises. What's HLA stand for? Hydraulic Lifter ___ ???

 

I would say it's a "lifter" thing if you can call it that with soobs. Except usually lifter noise goes away under accelleration or once the lifter builds pressure. This is a constant knocking. Imagine knocking on the valve cover with the handle of a wooden handle; that's what it sounds like.

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HLA = Hydraulic Lash Adjuster.. They can make a wide range of noises from a light tick to a heavy clack. Some Seafoam, Marvel Mystery Oil (MMO), or a 1/2 quart of ATF in the oil may help get them to quiet down. It took me about 3 months to get the ones in my XT6 to be quiet, and it ranged from one making various noises to what sounded like all of them rattling. I tried various grades of oils, with MMO, and ATF. Not sure what oil I have in there now, but I have some ATF in there. Haven't started it since before Thankgiving, but she was quiet last time it ran. Oil pressure was always good.

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HLA = Hydraulic Lash Adjuster.. They can make a wide range of noises from a light tick to a heavy clack. Some Seafoam, Marvel Mystery Oil (MMO), or a 1/2 quart of ATF in the oil may help get them to quiet down. It took me about 3 months to get the ones in my XT6 to be quiet, and it ranged from one making various noises to what sounded like all of them rattling. I tried various grades of oils, with MMO, and ATF. Not sure what oil I have in there now, but I have some ATF in there. Haven't started it since before Thankgiving, but she was quiet last time it ran. Oil pressure was always good.

 

So the ATF thing. I've done ATF "flushes" but are you suggesting I add a 1/2 quart to my oil and drive like that till the next oil change?

I always thought that was bad for long-term conditions.

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So the ATF thing. I've done ATF "flushes" but are you suggesting I add a 1/2 quart to my oil and drive like that till the next oil change?

I always thought that was bad for long-term conditions.

 

Don't think I'd go untill the 3k mark with it in, but a couple hundred miles won't hurt. Thinking I have around 2-300 on mine, but I do alot of short-trip driving in it, or did anyways.

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