90 240SX SE Engine noise

[DeltaZulu]

My son bought 240SX SE 1990 model from local used car shop. This was his first car. Solid body but it has a very noticable (rather loud) mechanical noise comes from the engine. The noise synchornize with rpm. First I thought it was a broken exhaust gasket but it is coming from the engine. I opened the cam cover and did not see anything wrong (timing chain looked rather loose). Plugs are burned OK. It has a 1/2 inch deep dent on the oil pan. No major oil leaks. It has enough power. If anyone knows the (possible) cause of this noise, please let me know. Thank you in advance.

[NISTECH]

check the chain guide they tend to break on the 2.4l

[Sickly240]

if it only does it on start up than it's just the chain gathering oil.......alot of ka's do that.

[DeltaZulu]

It is a constant metalic noise comes from the engine while it is running. It sounds like a valve or something is hitting (Large Tick-Tick noise). At any rate, excessively loose tension of timing chain concerns me and will check. Also, I am curious:

What is going to happen if I run (idle) engine with cam cover removed? This is just to see where the noise is coming from.

Thank you again.

[sleepyS13]

it will sling oil every where and make a very sloppy mess.Just get a mechanics stethoscope from local parts store you should be able to pinpoint were it comes from. But more than likely its th timing chain

[DeltaZulu]

I will check the timing chain. I hope the repair cost is not much.

Appreciate your comments.

[NISTECH]

check the plastic guide when facing the engine from the front it is on the right side of the chain. also if it is a ka24de meaning a dual over head cam engine check to see if the upper metal guide is broken off and just resting on the chain the early ka24de is famous for that later model engines nissan eliminated that upper braket so if it is broke just remove what is left of it and run it without it. wont hurt anything.

[DeltaZulu]

Thank you for your input.It's a single cam (OHC) version and I will look for the plastic guide inside the engine. Engine itself has enough power and hopefully I can get rid of this noise without major engine repair.

Thank you again. It was a great help.

[240sxgirl]

I had that same problem with my Altima with the Ka24de engine and the Nissan dealer said it was the plastic timing chain guides rubbing. It doesnt affect the performance at all it just makes a really loud clinky chain sound. It is a big job to pull it all apart or at least that is what the nissan dealer told me so I am still waiting to get it fixed almost half a year later.

[NISTECH]

your altima is slightly different then the 240 engine he's having a problem with but both engines do have a problem with chain guides breaking. I am guessing your altima is leaking oil from the front cover as well. that is one of the jobs i dread doing most in the dealership. it is quite involved and requires a substantial amount of patients to be 100% succesful in the reseal process. I would much rather do the timing chain guide on the 240 then the altima.

[drjohn]

This model has hydrolic lifters made into the rocker arms and they can also rattle. The dent in the pan can cause a oil starvation problem if the dent is deep and blocks off the oil pickup tube. More likely it's the timing chain. Don't drive it to much the chain will cut into the cover at the water pump jacket and pump water into the oil and can cause bearing damage.

[DeltaZulu]

Thank you all for very informative posts.

I opened the cam cover of KE24E today again and checked chain guide. On the left (passenger) side, the guide is plastic (or rubber) protected but on the right (driver) side one is a plain metal. Chain on the left has more tension than right side. Right side metal-guide is not giving any tention to the chain (just in contact with the chain). Is this the way supposed to be? Should right side guide have plastic on it? I cheked around the chain area and did not see any loose parts there. Since some of threads for cam cover bolts were stripped and I am assuming the previous owner(s) must have opened the cam cover quite often. If this is the problem, I assume I have to open front cover to access chain/guides.

Appreciate your input.

[NISTECH]

the guide that you see thats metal has completely come apart that should be covered in plastic as well . all the peices of it are most likely laying in the oil pan. yes you need to remove the front cover to make the repair. nissan has an improved guide to prevent that from happening again.

[DeltaZulu]

Again, thank you for your information.

Now everything is so clear to me. I am wondering if this is something I can do or should leave it to the mechanic. I have time but thinking if this is a good father-and-son project. Any input would be appreciated.

Thank you in advance.

[NISTECH]

ok as far as you doin it yourself. it all depends on your mechanical ability. I do this stuff for a living at a nissan dealership. for me its not a big deal. i think for you its going to be more then an overnight project if you havent done internal engine work before. just make sure you get your timing marks lined up and dont let the hydrolic tensioner pop out push it back into its bore and place a small pin through the hole to hold it in. those are the key things to doing this job. other then that its pretty much straight remove and replace parts. if you should decide to do it..good luck hope it works out for ya

[DeltaZulu]

Thank you again. I will try and see. Since I have enough time, I will take my time to complete it. I will be careful about marking timing.

[240dreams]

how much is to to replace of repair the timing at the dealership?

[Touchdown038]

A hell of a lot... probably up to around $800 for parts and labor... way better off doing it yourself. If you get the timing kit from Napa, it costs around $100 for all the parts, and as far as doing it yourself, just make sure you have enough time to do it in case something goes wrong. It's not hard, just time consuming.

PS. Make sure you buy the biggest bottle of Fast Orange you can... you're gonna need it at least I did

[240dreams]

thanks for the info guys. you guys really save me money and time.