# clicking sound in engine?



## therock0603 (Jan 20, 2008)

Hey guys. I have a 93 Nissan pickup. Now I used to hear this same clicking sound in the engine when I was getting low on oil (because my truck used to burn oil). It's a steady clicking sound that gets faster as the engine revs up. Well I just recently had to have a lot of engine work done because I had a burnt valve and the guide on my timing chain was broken. So the head was reworked, a few valves were replaced, timing chain was replaced, and it's been running fine (plus it no longer burns oil ). 

But last week I started noticing the clicking sound coming back, but this time I'm not low on oil. AND it only starts after I drive on the interstate for a little bit at 70-75 mph around 3000 RPMs. I'll get off the interstate and hear the clicking. But then if I turn the truck off and start it back up and let it sit for a second and start it back up, it stops. Sometimes I can even just turn it off while it's still rolling and start it back up and it stops.

So I've read other topics on random pages talking about how lifters can cause this noise. But since it only does it at those certain times, and it quiets down by just turning it off and starting it back up, it confuses me. 

Also, should having the head reworked have fixed any problems with the lifters or not?

And I've read mixed advice in these random forums I've checked. I've seen someone saying that it should be repaired or the engine could suffer further damage. But more often than not, people are saying that's something that happens with age, and it's really nothing that you need to worry about because it's not hurting anything.

So......opinions?

Thanks!


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## lumbee (Mar 20, 2005)

...my truck does the same thing...usually on long trips after it gets hot it will tick, and it comes and goes. I've never heard any good explanation for what it is. My theory is it has something to do with the hydrolic valves adjusters...like one gets stuck or something? At any rate it doesn't seem to have any adverse affect on the motor. At least the motor performance doesn't change any when I hear it tick. Assuming the tappets are the problem, replacing them would be the only fix. It happens pretty rare on my truck...if fact now that I think about it I did about 1500 miles over the holidays and don't remember hearing it any...or maybe I just ignore it now


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## smj999smj (Jan 1, 2006)

The usual problem is the hydraulic lifters, which are built into the rocker arms. When the vehicle is driven, the oil gets hotter and thinner, making the noise more pronounced. Another thing that can cause this is overfilling the crankcase, which causes the crank fillets to "whip" the oil and create air bubbles that could work their way up to the valvetrain. Many install 4 qts. of oil into the KA24E engines during an oil change, but it usually only requires about 3 1/2 to get the level to the "FULL" mark. It's also best to stick with a genuine Nissan filter and recommended 5W30 oil. As far as the lifters, you can either replace the rocker arms, take the painstaken task of disassembling the lifters and cleaning them out, or turning up the radio volume.


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## therock0603 (Jan 20, 2008)

So basically what you're saying is it's not doing any damage to anything and is just an annoying noise? I might try some Sea Foam, because from what I read somewhere else about a problem just like mine, it could be an obstruction in the flow of oil from the top of the engine back down to the area where the lifters are causing them to get a mixture of oil and air (the air being compressible) so it causes extra clearance in the valvetrain and causes it to tick. The thing is, I've always used 5W-30 and put exactly 4 quarts in.  It never made this noise before unless the oil was low.

Now...the 2 main questions:

1) Is this noise the sound of something bad happening? Does the fact that I hear a lifter(s) ticking mean that it is being damaged? Or will it do any damage to any other part of the motor if I allow it to continue?

2) Since I just had the head reworked recently and had the timing chain replaced and all (therefore meaning the engine was taken apart to some degree), could the fact that the lifters are making noise under these conditions now be a result of them doing something wrong? I don't know too much about motors, so I don't know if when the head was sent off to be reworked, if the lifters were part of that assembly and went with the head or if it stayed with the rest of the engine untouched. So could it be something overlooked or done wrong when the head was reworked or when everything was put back together?


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## OchnofConcrete (Jan 7, 2008)

question 2: the exact reason why there's so many DIY'ers out there that spend hundreds of dollars on tools.
there's no way to know.. because engine clearances are so small that easily a lazy builder could have just cleaned it and put it back together w/o checking clearances. there's no way to know, and no way to get your money back.
the clicking is normal for most engines... unless they are brand new.. the only way to have a perfectly new engine after a rebuild *of top or bottom end* is to do it yourself or take it to an expensive pro... and make sure everything is back to spec.. (blueprinting an engine)
the lifters on your KA24E is basically just like a V8 but wi/ slight difference and on only 4 cyl's... you're talking about several metal pieces that move in time with each other and naturally click... and over the years wear a lil... then ya got seals and bores that very tight and keep it all aligned. 

what the one guy said about the oil heating and thining is pretty right on... the clearances get smaller so the metal on metal contact is more audible... as why you can hear it after you get off the highway but it stops after turning the truck off. the only way to solve this is a very good rebuild... and someone that gave you a deal.... you'll not only be lucky to have had your vavle seals replaced... valves lapped, clearances checked... believe it or not... some A hole mechanics out there will take your engine apart... wait a few days and say they're workin on it, and then put it back together with just checking to make sure it's working right.

with the way it's ticking... use oils made for higher mileage. here's the prob with this.. thicker oil will protect better BUT... it doesn't move as quick and on an older engine you start losing life of the engine cuz of STARTING IT UP... oil's at the bottom of the pan... til you start it... and the oil is pressurized into all the cam/lifter/crank journals... your entire engine survives because metal surfaces are riding on a thin layer of oil.......... but thinner oil won't protect as much. so using high mileage engine oil's is the best for ya. maybe add some Lucas... or use Royal Purple.

either way... wi/o a full blueprint *putting everything back to factory spec* you're going to have the tick.


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## smj999smj (Jan 1, 2006)

I don't know if I'd say that the KA lifters are like that of a V8 (I'm assuming "V8" refers to that of a Chevy or Ford?? Those engines have an in-block cam and pushrods). The KA24E is a 12-valve engine with an overhead cam and dual rocker shafts. The lifters are tiny and fit inside the end of the rocker arm. It's not hard for them to get clogged up with debris or sludge and when they do, they usually start to tick. A little bit of ticking is sort of the norm for these engines. I've yet to see where it's done any damage. Cleaning the lifters or replacing the rocker arm set usually quiets them down quite a bit, but whether it's worth the money or effort will depend on you. If you do work on the rocker arms, pay careful attention to them as they are all not the same. I believe there are 4 differant part number rocker arms, if I remember correctly.


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## OchnofConcrete (Jan 7, 2008)

well, i know it's not the same as inblock cam and pushrods... i was making a broad generalization... as in, the KAd is more similar valvetrain style to a v8 that it is to a KADE.


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## therock0603 (Jan 20, 2008)

So another question I have is when I'm hearing the loud ticking of the lifters in the engine, what is it exactly that I'm hearing? Like what is making contact with what to make the ticking sound?


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## OchnofConcrete (Jan 7, 2008)

smj999smj said:


> The KA24E is a 12-valve engine with an overhead cam and dual rocker shafts. The lifters are tiny and fit inside the end of the rocker arm. It's not hard for them to get clogged up with debris or sludge and when they do, they usually start to tick. A little bit of ticking is sort of the norm for these engines. I've yet to see where it's done any damage. Cleaning the lifters or replacing the rocker arm set usually quiets them down quite a bit, but whether it's worth the money or effort will depend on you. If you do work on the rocker arms, pay careful attention to them as they are all not the same. I believe there are 4 differant part number rocker arms, if I remember correctly.


what he said..


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## OchnofConcrete (Jan 7, 2008)

get the FSM off of someone on here. it'll show and explain how everything goes together.


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## therock0603 (Jan 20, 2008)

noob question...what's FSM stand for?


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## OchnofConcrete (Jan 7, 2008)

lol, Factory Service Manual.
it's the 600 dollar version the dealership tech use direct from the engineers.
has absolutely everything on your car. down to the smallest screw/bolt.

if you're lucky, you just keep askin and someone might have it on the net so you can get it for free.

i'm just lucky cuz i've got a car that a lot of ppl mod and work on.


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