Really confused by noise on 240 sx

[Nissangirl]

I really need some advice!!!!

Heard a tapping/weird noise from the engine of my 96 240sx this week. Took it in to a local garage and they say I need to replace the timing chain. However I talked to other Nissan mechanics and they say it's unlikely the chain is faulty as they are made to outlast the car. i can't get anyone to check the car out until Monday now, and don't know if I should even be driving it. The Goodyear guy scared the crap out of me - yet the other guy is saying the diagnosis is unlikely. what could it be - and what the hell should I do as I do need to use the car later. Please, any advice would be welcome right now. the car has 130,000 on the clock and otherwise runs fine.Many thanks in advance

[silkk]

Maybe its a bad chain guide.

[Nissangirl]

thanks for reply. If it is the guides, is it a good idea to remove them opposed to getting them fixed?

Do you know how long the chains are supposed to last? Ie; the mechanic was pretty quick to suggest it was my mileage (130,000) that was the cause of the problem, In any case, is it OK to drive for the next day or so?

[s13sr20chris]

ok, there is one guide on the very top that you can get rid of. the other guides are very important. you need to pull the valve cover and check for chain looseness. the dohc has two separate chains and the bottom chain is more likely to go out but is very hard to check. you have to pull timing cover off. chain is built to last forever but lack of oil change or other factors can cause it to fail prematurely.

[skydragoness]

So a tapping noise is automatically believed to be the timing chain guides going?

It's true the timing chain should last for a long time, but if the previous owner didn't change the oil on time/or infrequently and drove the car hard, the guides get mangled and can even chip apart.

Nissangirl, does it sound worse upon start up? (like a horrible rattling?) Because that would signify the chain being loose.

s13sr20chris: I've heard of the main bearing/guide at the top is a useless part and can cause a lot of excess noise. Would the Nissan dealer do that service? I've noticed my engine has always been somewhat noisy at idle. I've been told that the injectors on the KA are notoriously loud, that i could have valve-tap, and then the last one about the timing chain. I only have 110k. So i find that unnerving.

(I sympathize with you on your problem Nissangirl, seems as though you can never get an honest opinion from a mechanic if your'e a woman.)

[s13sr20chris]

s13sr20chris: I've heard of the main bearing/guide at the top is a useless part and can cause a lot of excess noise. Would the Nissan dealer do that service? I've noticed my engine has always been somewhat noisy at idle. I've been told that the injectors on the KA are notoriously loud, that i could have valve-tap, and then the last one about the timing chain. I only have 110k. So i find that unnerving

main bearing? i have not had any probs with the main bearings. i do know very well the top chain guide. it is useless and i used to remove one a week. havnt had one in a while though. all nissan galley feed(also known as side feed) injectors are very loud. its just the way they are.

[Nissangirl]

Thanks guys for your invaluable input. I freely admit to knowng very little about car maintenance (1st car), and subsequently realized my oil was almost empty. Threw two quarts in and most of the noise disappeared. Today i took the car to a mechanic who spent 15 years working on Nissans and he assured me there was nothing wrong with the timing chain, and the little rattling that was left is normal in a car with my mileage (130,000). he spent an hour checking stuff with no charge, and so I'm going to get him to do a full service next week, just to be on the safe side. He also said I could go back and watch them so I can pick up how to do the basics - so cool!! My lesson here: Learn the basics and don't rely on the first diagnosis, as the Goodyear guys just wanted to make a few bucks out of me, knowing I was a novice. thanks again Guys !!! P.S Anyone living in Fort Lauderdale and needs a great mechanic - I have his number!

[skydragoness]

Whoa, the noise you were probably hearing was due to the lack of oil. Good thing you caught it in time. Great to hear that you find a Nissan mech, anyone who has a good knowledge of the 240 is invaluable indeed.