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L16 Ticking noise after head work


d.p

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Some may have read my other head gasket thread but it was getting long and I want to focus on the problem at hand now.

 

So, took the head off and had the following done:

 

1. Valve job

2. New valve stem seals

3. Milled .005"

 

Put it all back together with new fel-pro gasket kits. 

 

1. Filled with coolant but forgot I broke one of the thermostat bolts so coolant pissed out that side of the head.

2. Replaced the bolt refilled with coolant and fired it up and it sounded good: All put back together.

3. Didn't drive it, next day changed oil (4.5 quarts of GTX 10w-30) and filter (Bosch)

4. Drove it around the block and it had good power, better than it ever did before and sounded ok

5. Once engine got warm loud ticking noise started: Ticking

 

I checked the rockers and they are all tight, chain seems tight no slack on the passenger side and looking down towards the crankshaft it looks fine, just like it did before I took the head off.  Engine guy doesn't think its the valves, he thinks something might have come loose under the valve cover but I can't find anything obvious.   Could it be exhaust manifold leak?  Sound seems to be coming from the front area of the valve cover.

 

If not any ideas on what to check before I take it to a professional and have them tell me? 

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Yah I figure issue is either rocker or exhaust related but not sure how to diagnose either?  That is my problem.  

 

Can I run the engine with the valve cover off to see if the sound is coming from there? 

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The frequency of the noise is too fast to be a single valve. It does sound like an exhaust leak, but from the collector flange. But it also sounds like a chain tick from inside the cover.

 

  • Did you ever get a visual on the tensioner plunger? If it was popped out and you muscled it back together anyway, the rubber could have worn off quickly and cause this noise.
  • How about the thermostat housing bolts? There's one that has an open hole to the inside of the head at the timing chain. If the bolt used is too long, it can contact the timing chain and make that noise.

I think your problem is in the timing chain somewhere. Look at Mike's reply (#3) on this thread http://community.ratsun.net/topic/41595-timing-chain-wedge/and you will see what it looks like when the tensioner pops out.

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This is what my chain looks like now:  

 

34800956485_af071df609.jpg

 

If it was the tensioner I would think the two sides of the chain down low would be touching almost like in mikes pic?  If so that is not the case on mine.  Is the slack side the pass side because I can slide that side of the chain back and forth.  

 

It was the rear thermostat bolt that broke and the replacement was spot on in length.  The longer one on the front is still OEM as far as I can tell and that is the one that goes into the head behind the chain.

 

Sucks about the VC and oil because it would be super easy for me to see where the sound was coming from if I could just do that.   :P

 

I just bought a compression tester so if someone can walk me through it I will do it right now.  

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Posts are never too long, some go for many hundreds of pages. What you need is a build thread for all of this instead of double posts where two people replying don't know what was asked and answered before on an unknown post.  In addition you don't have to update several posts or go looking for them and you have basically a diary or what was done.

 

Ticking after the head was worked on is simply a progression of the first post.

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When u do compression check, make sure engine is warmed up, disconnect coil, screw in type is much more accurate, helps when someone cranks it for you while reading compression, or get remote starter, also open throttle all the way...

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I just did my first compression test, warmed up the engine for a minute or so.  Disconnected main coil wire, removed spark plugs, disconnect fuel line, opened the choke all the way and then cranked it 5 times on each cylinder and got 120 across all 4.  I did not have my foot on the gas pedal when I did this, should I? Also maybe engine wasn't hot enough to get an accurate reading?  Hesitant to let it run forever for fear of something letting go. 

 

And I have the screw in compression tester.  

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I think the big thing is that all are the same. if you have one different it would be a problem. but if ya have it apart still. do it again with the throttle open and see what differences you see.

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Exhaust leak would be louder under load and softer when let off.

 

Some may have read my other head gasket thread but it was getting long and I want to focus on the problem at hand now.

 

So, took the head off and had the following done:

 

1. Valve job

2. New valve stem seals

3. Milled .005"

 

Put it all back together with new fel-pro gasket kits. 

 

1. Filled with coolant but forgot I broke one of the thermostat bolts so coolant pissed out that side of the head.

2. Replaced the bolt refilled with coolant and fired it up and it sounded good: All put back together.

3. Didn't drive it, next day changed oil (4.5 quarts of GTX 10w-30) and filter (Bosch)

4. Drove it around the block and it had good power, better than it ever did before and sounded ok

5. Once engine got warm loud ticking noise started: Ticking

 

I checked the rockers and they are all tight, chain seems tight no slack on the passenger side and looking down towards the crankshaft it looks fine, just like it did before I took the head off.  Engine guy doesn't think its the valves, he thinks something might have come loose under the valve cover but I can't find anything obvious.   Could it be exhaust manifold leak?  Sound seems to be coming from the front area of the valve cover.

 

If not any ideas on what to check before I take it to a professional and have them tell me? 

 

No where does it say the valve lash was set or checked. Hot engine 0.010" intakes and 0.012" exhaust. Eliminate the simple cheap and easy things first.

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Tried to do compression test at WOT and the gauge didn't read shit in any cylinder so I think it shit the bed. And I don't have a wrench thin enough to adjust the lash. Head guy did adjust to .010 .012 while it was out.

 

Does sound chain related. Louder under the engine towards bottom of timing cover.

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Posts are never too long, some go for many hundreds of pages. What you need is a build thread for all of this instead of double posts where two people replying don't know what was asked and answered before on an unknown post.  In addition you don't have to update several posts or go looking for them and you have basically a diary or what was done.

 

Ticking after the head was worked on is simply a progression of the first post.

 

^ That. Too many threads, all about the same topic-your truck.

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Which thermostat bolt goes into the head far enough that it would matter? I only broke the rear one which is the shorter of the two. and as far as I know it's the same length as the one I broke.

 

ZDDP Nah but I was going to. Head guy recommended it.

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You guys need to understand that all these older engines are noisy, they will never sound like your modern engine in your modern vehicle.

I have a tick in my LZ23 I built, I have learned to ignore it, half the time it's not even the engine, it's something bolted to the engine.

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Take the valve cover off. If not the bolt, set the valve lash.

 

Just did mine, again. Did them yesterday but let the car sit too long looking for my tools before starting the job. Definitely could hear a tic when hot. Three exhaust would let a 0.013" feeler through. Reset them.... again.

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I am pretty lax on my valves, I warm it up and then take a .015 feeler gauge and try to slide it between the arm and lobe, if it doesn't go thru I adjust that one to .012, all have to have the .012 gauge go thru.

I have been doing it that way for years, my biggest fault is not changing the oil/oil filter enough, but my previous L20b engine in the work truck lasted over 15 years, and I beat the shit out of that engine, fact is the block was lightly used when I put the fresh head on it.

I believe if you keep oil and antifreeze in the L block, and you don't rev it over 4500rpms very often they will last a very long time.

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