CA18DET NOISES

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harukisan
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Joined: Fri May 31, 2013 12:40 pm
Car: 1989 Nissan 240sx coupe right hand drive, sr20det and 1989 JDM Silvia Ks model w/CA18DET

CA18DET NOISES

Postby harukisan » Fri Aug 12, 2016 9:15 am

Hi Guys,
Once again I am seeking help with my Car (real jdm silvia 1989 with original CA18DET). I have been searching and trying to track down a squeaking noise that is driving me crazy. First I have checked all the belts and pullies, alternator, AC compressor, power steering etc. What I have come up with is the CAS is the culprit. I have installed about 6 different CAS 3 of them being new ones. After putting in a new or different CAS the noise problem goes away but only to return. I have had professional mechanics check it out with no answers except that they think the engine itself is healthy, my last try just yesterday with a mechanic said it's the CAS. I just happened to have a brand new CAS and it was installed and the noise was gone until today it came back. This guy said that maybe it is because that little tab that is on the exhaust cam to line up with the CAS has broken off sometime in the past and maybe because of that and not having a good lock up with the cam itself causes the CAS to squeak?

My question is has anyone out there with a CA18DET ever have this problem and is installing a new cam the only answer/fix. Can I just replace the exhaust cam alone with let say a stock one or maybe a Tomei hydralic unit that I won't have to adjust my tune and go to the dyno again. Or do I have to replace both. The engine is the original one with only 70k miles.

Any insight or info with this issue would be greatly appreciated.


boost_boy
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Re: CA18DET NOISES

Postby boost_boy » Wed Aug 17, 2016 4:26 am

You should really try to provide a video of the noise that's concerning you. Going through all of those crank angle sensors is pointless. Perhaps the alignment dowel pins are missing on the upper timing cover that houses the crank angle sensor and if that is the case, no matter what you put on there, it will always make noise and possibly destroy every crank angle sensor you put on there. If you are 100% your issue is in that area, you should remove the upper timing cover to see if the alignment pins are still there. Let us know how this goes.

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harukisan
Posts: 45
Joined: Fri May 31, 2013 12:40 pm
Car: 1989 Nissan 240sx coupe right hand drive, sr20det and 1989 JDM Silvia Ks model w/CA18DET

Re: CA18DET NOISES

Postby harukisan » Wed Aug 17, 2016 6:30 am

Hi, hey thanks for reminding me, I do know for a fact that I am missing one of those dowel pins. I found that out the last time I thought I had timing issues during a dyno session. My tech told me that it doesn't matter about that pin but even then I thought he was wrong. Anyway do you have any idea where I can get those dowel pins? I will try and get a video up and I will schedule removing that upper timing cover, I guess I should also replace that exhaust cam while I'm at it, I am looking for a cam too. It looks like the Tomei is my only choice because using a used cam worries me, I was hoping I could just replace the exhaust side. Please lmk about those pins.

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harukisan
Posts: 45
Joined: Fri May 31, 2013 12:40 pm
Car: 1989 Nissan 240sx coupe right hand drive, sr20det and 1989 JDM Silvia Ks model w/CA18DET

Re: CA18DET NOISES

Postby harukisan » Wed Aug 17, 2016 7:42 am

Thanks guys and thank you boost boy for that reminder. I have a youtube video with that noise
https://youtu.be/rqUU0ODtcLg
I would appreciate any input on what it might be. I am thinking that boost boy hit the problem right on the head (the missing dowel pin). I had forgotten about that ( I was just so happy after the last time I had a problem and got it dyno tuned with nistune and all I just forgot about that dowel pin), Oh well, I will be taking the Top timing cover of and checking for tightness on all bolts. Anyone know where to get dowel pins?. it is a shame I have probably ruined a few CAS just driving around not realizing what that noise probably is. I will keep you posted. Oh yea does anybody know if I can get away with just replacing the stock exhaust cam with a Tomei 256 lash type exhaust cam or will I have to replace the set (both intake & exhaust). I'm also looking for a good stock exhaust camshaft that still has the CAS alignment pin still in place although I am worried if I go used and there's a problem with that cam I would have to do it all over again.
Thanks, any help would be greatly appreciated.

User avatar
harukisan
Posts: 45
Joined: Fri May 31, 2013 12:40 pm
Car: 1989 Nissan 240sx coupe right hand drive, sr20det and 1989 JDM Silvia Ks model w/CA18DET

Re: CA18DET NOISES

Postby harukisan » Fri Sep 09, 2016 8:28 pm

Update, I replaced the exhaust cam and the guides pins that are behind the upper timing belt cover and it seems that the noise is fixed. It's been a week with some hard driving sessions and so far all is well. Thank all you guys with your suggestions. much appriciated.

KippoSleek
Posts: 2
Joined: Wed Jun 21, 2017 10:51 am
Car: 1993 S13 SE Coupe with a CA18det

Re: CA18DET NOISES

Postby KippoSleek » Wed Jun 21, 2017 10:55 am

harukisan wrote:
Fri Sep 09, 2016 8:28 pm
Update, I replaced the exhaust cam and the guides pins that are behind the upper timing belt cover and it seems that the noise is fixed. It's been a week with some hard driving sessions and so far all is well. Thank all you guys with your suggestions. much appriciated.
Sorry for digging up an old thread, but where did you happen to find the guide pins (dowel pins) for the upper timing belt cover? I'm in the process of rebuilding my engine and I'm missing one. Any help would be greatly appreciated.


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