Timing belt help
Timing belt help
Installed a new timing belt on my Infin. M30 it is a VG30E single overhead cam engine. The FSM is a bit confusing on how to set the belt tensioner. It describes setting the belt above the tensioner to 22 ft lbs, then to set a feeler gauge between the tensioner pulley and the belt. It seems to me once the pulley is set to spec the feeler gauge would have no effect on the belt tension because the belt would flex a little anyway? Is there someting I do not understand? I am wondering if I got the tensioner to tight, I hear a low pitched (humm) at idle. Also noticed my timing was off 15 deg after the install. Thanks for your input.
When you installed the belt did you lign up the 3 marks on the belt with the dots on the gears,forget the dots on the back cover they will not match up perfectly. As long as the dots on the gears line up with the lines on the belt your timing should be right on, if you did not line up those marks,there is where you timing being off is from.
The hum usually does mean its too tight. Best way to set up the belt is install it. have your tensioner sitting so it is rolling into the belt under its own spring tension. then take a 14mm and slightly rotate the passenger cam shaft counter clock wise about a half an inch. this will take all the slack in the belt and put it in the tensioned section of the belt allowing the tensioner to take it up. Tighten the 14mm bolt on the tensioner. after you have tightned it. take your hand and push down on the belt between the cams. This will now move the slack to that point. To check your belt tension you should be able to twist the belt to the point the ridges of the belt are vertical with little force. if you cant get it with out grabbing the belt and giving it some effort to reach that point its too tight. If it easily goes to that point and will continue going around with little effort its too loose. The allen hex in the tensioner is usually between 5:00 and 6:00 when properly set.
The hum usually does mean its too tight. Best way to set up the belt is install it. have your tensioner sitting so it is rolling into the belt under its own spring tension. then take a 14mm and slightly rotate the passenger cam shaft counter clock wise about a half an inch. this will take all the slack in the belt and put it in the tensioned section of the belt allowing the tensioner to take it up. Tighten the 14mm bolt on the tensioner. after you have tightned it. take your hand and push down on the belt between the cams. This will now move the slack to that point. To check your belt tension you should be able to twist the belt to the point the ridges of the belt are vertical with little force. if you cant get it with out grabbing the belt and giving it some effort to reach that point its too tight. If it easily goes to that point and will continue going around with little effort its too loose. The allen hex in the tensioner is usually between 5:00 and 6:00 when properly set.
Re: (NISTECH)
Thanks so much for your reply NISTECH. Looks like I am under the hood for round two! I am sure the belt went on right because my FSM has actual tooth counts between crank mark (40teeth)and cam mark then cam mark to cam mark (43teeth) but I will recheck. In reading some threads and yours I think I set the tensioner to tight. I noticed when I set the tensioner the tensioner spring did not touch the stud, so maybe it needs to be rotated a complete turn to make contact. I think when the FSM is translated from japanese things get distorted, who knows. I found on the net last night several companies selling belt tension test machines, Gates has one, am not sure exactly how it worked other than it had a digital readout in lbs. for setting the tensioner/belt.
I really admire mechanics these days, you guys are amazing in the amount of knowlege you have. Ill bet you get a kick out of guys like me with just enough skill to be really dangerous! The days of the shade tree mechanic are quickly ending.
Again Thanks, Steve
I really admire mechanics these days, you guys are amazing in the amount of knowlege you have. Ill bet you get a kick out of guys like me with just enough skill to be really dangerous! The days of the shade tree mechanic are quickly ending.
Again Thanks, Steve
Steve the main reason I decided to do this online thing is my feable attempt to reduce the amount of hack work we recieve at the dealer after someone else hoses up a nissan/infiniti product. You would be suprised at what some people will do ,even independant shops, in trying to fix their cars.
As far as your tensioner goes rotate it clock wise till the spring hits the stud. the hex at that point will be between 12 and 3 at rest. Then continue rotating it till it is at about 9:00 sinch the nut down so it wont move back then install your belt. If you got the factory belt it will have painted lines on it 2 solid and one dotted . The dotted line goes on the passenger[right hand] cam gear,aligned with the dot on the gear, following the belt to the drivers side [left hand] you will find mark #2 , a solid line, place that on the dot on the gear for the left hand cam. then folow the belt down to mark # 3 and place that on the crank gears dot. No need to count the teeth if you follow those marks. once all is in place loosen the tensioner nut and it will spin into the belt and rest right around 7:00. Then adjust the tension as I mentioned in the other post. Note you may need to asist it to get the tension to the right place,like use your allen to turn the tensioner a bit into the belt then let it rest and do the adjustment. It depends on how strong the spring still is and how much build up is on the spring weather or not it will self adjust to the proper point.
As far as your tensioner goes rotate it clock wise till the spring hits the stud. the hex at that point will be between 12 and 3 at rest. Then continue rotating it till it is at about 9:00 sinch the nut down so it wont move back then install your belt. If you got the factory belt it will have painted lines on it 2 solid and one dotted . The dotted line goes on the passenger[right hand] cam gear,aligned with the dot on the gear, following the belt to the drivers side [left hand] you will find mark #2 , a solid line, place that on the dot on the gear for the left hand cam. then folow the belt down to mark # 3 and place that on the crank gears dot. No need to count the teeth if you follow those marks. once all is in place loosen the tensioner nut and it will spin into the belt and rest right around 7:00. Then adjust the tension as I mentioned in the other post. Note you may need to asist it to get the tension to the right place,like use your allen to turn the tensioner a bit into the belt then let it rest and do the adjustment. It depends on how strong the spring still is and how much build up is on the spring weather or not it will self adjust to the proper point.