# weird problem.



## Bryan200sx (Jan 23, 2003)

*weird problem. please help*

Hi about for about a month my car's A/C hasent been cooling as well as it should be ( only cooling when moving/ or at night) then when i turned it on yesterday it made a real werid noise by the belts it sounded like my belts were going but their is also a real back knocking sound. while doing that the car lights up the battery with the brake like at the same time. this only happens when i put the a/c on. i checked the amout of volts coming out from the alternator when the a/c is on is 14.3 when the a/c is on it goes to about 12.3 any help will apriciate


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## Bryan200sx (Jan 23, 2003)

well i saw what the problem is..... the crank pully is messed up i was looking at it wobble. its in 2 pices. i remember that it was one solid pice when i did my front main seal. the bearings or dampener inbetween the two rings is gone.... has this happend to any one. i mean its not a big deal its just getting a new pully but any ideas as to what made it get like that.... ill try to post pix as soon as i can.


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## Bryan200sx (Jan 23, 2003)

pix of the problem seems no one knows what im talking about or cant picture it http://www.cardomain.com/memberpage/626608/7


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## nova73guy (Mar 30, 2004)

It's not unheard of for a crank pulley to go bad, especially if it's got some miles on it. Actually, it's also the harmonic balancer for the engine. Over time the rubber between the outer ring and the hub wears down causing the two pieces to separate. I'm just guessing but it sounds like that's what happened to yours. Again, not an uncommon problem.

edit: Just saw the pics. That's what happened alright. The material holding the two together just degraded and the thing fell apart.


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## Bryan200sx (Jan 23, 2003)

what usually causes that to happen normal wear and tear. because that thing started making this crazy ass nosie from one day to the next


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## myoung (Apr 15, 2002)

sounds like a perfect excuse to buy a UR pulley.. :thumbup:


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## Bryan200sx (Jan 23, 2003)

your right...... but im low on funds right now. ( 17 and unemployed) but i really want one. any one know what causes the pully to get like that? manufacure defect?


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## nova73guy (Mar 30, 2004)

Bryan200sx said:


> any one know what causes the pully to get like that? manufacure defect?



No defect, just normal wear. I've seen them go 150k+ miles or crap out at around 70k. Just one of those things that wear out on a motor. My SE-R has around 82k on it and I'm probably gonna have to replace mine soon, but I'm waiting 'til I have funds to fix a few things at once.


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## Jopet (Aug 10, 2009)

I thought to bring this up. I went and fix a couple of things on the car and also checked my timing. I couldn't find the timing marks with the timing light. 
It seemed that the crankshaft pulley had moved. I guess its going out. Maybe due to having to remove and install it when I replaced my crankshaft front oil seal. Maybe. 
Reading this thread also makes me think, with my past timing setting as well, if the pulley wears out and the timing marks move, it is possible that we are setting our timing on the wrong position.


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## skeeter123 (Apr 30, 2010)

I replaced the front oil seal on my 98 GA16; the crankshaft pulley is keyed so that it only goes on one way; can't be "off" a few degrees. Not sure if the timing marks are on the part that's part of the harmonic balancer; could be if it's separating that it could shift the timing marks....

BTW I know that the Ford 4.0 liter V6's are famous for having the harmonic balancer separate.... but never heard of it happening on the Sentra's....

OP: for some reason didn't see any pics of the problem at ur link, just of the nitrous setup.... on second thought, maybe that's what stressed out the crankshaft pulley...


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## jdg (Aug 27, 2009)

It happens, not often, but it does happen. I've got 2 B14's, 187K miles & 168K miles. Both of them are still good...for now anyways.
Two piece balancer/pulley, rubber (or something like it) in between the two pieces. Vibration or whatever kills it eventually and the timing marks magically move around.


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## Jopet (Aug 10, 2009)

Yup. I thought that would not happen, but it does. Had to get my timing corrected yesterday by listening to the pinging. I move the distributor when looking for the timing marks. Had to stop driving, adjust about 5x.


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## skeeter123 (Apr 30, 2010)

I also have been doing the on-the-road timing bit; but I thought it was my lack of skill, cheap timing light, and iffy timing-mode setup. Is there a way to look at the crankshaft pulley and see if it has slipped? Alignment marks, etc?
When it slips, does it slip a little and stay put, or does it continuously slip a little all the time? Once it starts slipping, does it totally crap out shortly thereafter, or can it go for months/years slipping completely around. Geez, does it even slip in only one direction?
So many questions, and this ain't in the FSM.


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## Jopet (Aug 10, 2009)

TDC on the #1 spark plug. Open the distributor cap. turn the engine so the rotor is facing the #1 tower (might need to tap on the ignition key to turn the engine to get it at the general area). Pull #1 plug, get a wire at least 2 feet long, stick it in the plug hole, turn the engine by hand until you are sure that the wire (piston) is at its highest point. This should be top dead center (TDC). Now take a look at your pulley, the timing mark should be on 0 degrees. Mine was not, marks were nowhere near.
Not sure how long my pulley will last after this though. The older post will show that, eventually, the pulley will separate, not completly though, but will be turning at different speeds when the a/c is turned on


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## skeeter123 (Apr 30, 2010)

Jopet, thanks.... with that advice and a bright flashlight I should be able to see if that's what's going on.... and it won't involve a protractor....


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## jdg (Aug 27, 2009)

x2 on post #14.
That's how I determined my marks/pulley had NOT slipped...(well, hadn't slipped _yet_ anyways).


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## payk (May 5, 2004)

could be the timing belt tensioner is going bad


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