I have a 1995 Infiniti J30 with 105,000 miles. I replaced the timing belt and water pump. I used an actual shop manual to make the repairs. Everything went smooth with the repair. The timing belt appears to line up on all points (the crankshaft and cams). However, the car is very difficult to start and when it starts, lacks power and will not idle. Furthermore, the car appears to run rich. I changed the plugs with new platinum plugs but with no change.

I took everything apart again and examined the timing belt. Again, it appears to be align with the markings. I took the belt off and reinstalled it to see if any improvement would be made. The car still does the same thing. It will not start unless the throttle is floored and even then it is very hard to start (acts like it is either getting too much gas or starving for gas). I do get a lot of smoke after it starts and the spark plugs appear to get really oily (making me believe it is running rich).

I changed a timing belt on a Nissian 300 ZX two years ago with no problems (same engine and timing belt system). The belt was a little difficult to align on the 300ZX (one cam was always off by 1/3 or less of a tooth), but ran perfect. The J30 seems to have the same issue.....the belt looks aligned but is off by less than 1/3 of a tooth on one cam. I have played with the belt several times but can't seem to get it any closer. I did the same thing on the 300 ZX, hoping to get the alignment closer with no success, but the car ran perfect.

The Infiniti dealer tells me that one cam is usually slightly off on the alignment by just a fraction or so (he says it is impossible to be exact and one sprocket is normally off by 1/3 of a tooth or less). However, four of the five points line up exact (including the crankshaft) and the fifth point is very close to the marking (less than 1/3 of a tooth).

I have checked all connections, hoses and even compression and everything seems okay.

Any ideas of what I might have missed? Your ideas are welcomed. Thanks.

Hello Rocket,

Man, I feel your pain. I have done two belts on my M30, it's the VG30. A couple questions. Were you at TDC #1 compression stroke when you installed the belt? You need to watch the distibutor rotor to be sure.

In your FSM it should list the number of teeth between the timing marks. Mine says, total number or teeth, #of teeth between LH and RH camshaft sprockets, # of teeth between LH camshaft sprocket and crankshaft sprocket.

Makes sense, so you can double check the new belt and your installation. I did notice while installing the belt that the punch marks on the back of the belt cover were not super acurate(reference only). The arrow on the belt must point forward, I am sure you noticed.

On my first belt I had trouble with the tensioner setting. There is a great tech on the Nissan mechanic section(this site) His name Is NISTECH. Give a post there too.

Good luck and let us know how it goes.

Steve

Did you use a timing light ot check to see if it was at required settings? This will tell you if your in or out of time! Plus check your ECU for codes!

Problem solved. The issue was with the timing belt. The timing belt I purchased from NAPA was mismarked at the crankshaft marking (one tooth). I returned the belt and purchased a new belt from Nissan. The Nissan belt aligned much better with the slots on the cams and crankshaft. I also replaced the tensioner to be on the safe side. The car fired right up and runs great.

I appreciate the ideas and help. This is a great forum.

Haha, just teaches you to always get OEM for important parts.

You have bad luck man. What are the chances of getting a belt stamped wrong? It really brings up the question of how bad is thier quality control.

If the belt is stamped wrong I wonder how good the actual belt construction is. Is NAPA now using low cost vendors, I always thought thier parts were good quality.

Glad to hear you are up and running again, sorry about all your wasted time on the bad belt. I wonder what damage may have occured if the belt mark were off by ten teeth. Valves hitting pistons??

Thanks, Steve