Belt Tensioner problem

[groundrocket]

I just bought an '03 G35 - drove it home and all was well - went to start it and heard a metal clank under the hood. I found both of the belt tensioners laying in the belly pan (A/C and alternator/power steering) and the belts were obviously loose. The tensioner pulleys were slightly different - one has a sheetmetal plate that was stuck to the front of it with a little bit of grease. After digging around in the belly pan I found one of the nuts and bought a second one. I put them back in and tightened them appropriately (both the tensioner bolt and the pulley locking bolt on each) and it drove/ran fine for the day. Later on I started it again and heard the clank again - the power steering/alternator tensioner had come off again and the nut on the other one is loose as well. I hope someone on here knows enough about theese to verify a few things for me:

1. are the nuts that hold the tensioner pulley on supposed to be locknuts?

2. does anyone know if the pulley with the sheetmetal plate on it is the power steering one or the A/C one?

3. does anyone have a pic or exploded view of theese pulleys so I can verify if I have the correct ones on the car?

4. Anyone else have this problem before?

I'm guessing that someone had underdrive pulleys on the car previously and pulled them before selling the car to carmax and just tightened the tensioner bolts forgeting to tighten the pulley nuts or some genius mechanic forgot to tighten them when replacing the belts prior to puting it out on the lot...

Any help would be appreciated.

Thanx for any help in advance,

KJ

[tollboothwilley]

I actually just replaced a tensioner pulley for the AC since it threw a belt and popped the Alternator belt off at the same time.

Both tensioner pulleys have the same setup.

They don't have lock washers, they just need to be tightened down enough as to not come loose.

Loosen the tensioner, remove the belt, and spin it freely. You are checking to make sure the bearings are not out. My guess is that they were just not correctly pieced together when reinstalled(if that is what happened).

Sorry i didnt take any pics of the process, as it is so easy to get to I figured it wouldn't be necessary really.

Take a look at the service manuals that are posted in the sticky though, i bet you can find a pic of how the pulley should all go together.

[groundrocket]

I checked the torque spec and its listed at 24 lbs if I remember correctly - I'm certain that I had it at least that tight and searched the shop manual until about 1:00 a.m. last night for pics - the only diagram showed the belt path and the locations of the pulleys but no pics or exploded views - I'm headed back to the parts place to find some 10mm lock nuts to get me through till I can get it into the shop to see if the correct pulleys are on it...

I'm starting to lean toward the previous owner having a different pulley setup with maybe a blower as one of the idler pulleys has the dreaded yellow paint mark on it from a junk yard purchase...

Thank you for your input!

[groundrocket]

Well a little locktite did the trick until I can get it into the shop - the pulley on the A/C side is not the right one or its missing a spacer as it dosent line up correctly...

After reading various posts on here I think that someone put an engine out of a newer model in it as the dipstick location is up front instead of down low on the side... I'm wondering if I should return it to the dealer and swap for one of the other dozen they had on the lot - cept it was one of 3 with a stick and the others were red - don't need the extra attention from CHP.

Before I get crazy and return it I'll have the infinity shop do an inspection and tell me anything that isn't right on the car- so far I noticed the yellow paint marks on several of the engine bolts that makes me think the motor came from a wrecking yard, the problem listed above with the idler/adjustment pulleys and the driver seat is just slightly different than the passenger seat - it has a different stitch pattern on the bottom part of the seat with a rounded panel in the middle while the passenger seat has a straight stitch down the center.

[tollboothwilley]

this car had a clean title when you bought it?

sounds like you may have had a lot of things replaced in that car

i would be very suspicious

[groundrocket]

Just looked at a co-workers G and found out that the seats on his are the same way... I'm off to the infinity dealer to get an eval of mods to the car and to find out if the motor has been changed, get the belt tensioners replaced with the correct ones, etc...

[G_whizz]

Good luck!!

Keep us posted!

[iz310]

i thought it only happened to me. since i had my G. its been going to infiniti service. i had the belt replaced and everything as soon i left the place i heard a loud noise and dash lights went on. dealer had to pay for towing, new belts and parts as well as the labor. they kept the car and gave me a loaner. only made sense since they fixed it. its been almost two months and no problems.

[smockers83]

Very strange indeed. That motor is definitely out of a newer model.

[groundrocket]

Just heard back from the dealer - They said the numbers match the car but both idler pulleys were missing spacers or had the wrong ones, etc. Said that the car had had regular services and everything else looks fine - the only things found incorrect were a missing vacuum plug and a few bolts for the air box and the missing parts for the pulleys - they want $500 to replace both pulleys as supposedly they cant get just the spacers... sounds strange to me. I'm verifying that someone at the place I bought it is still paying for it...

wish me luck...

KJ

[groundrocket]

OK - its all fixed - final total $562 for 2 idler pulleys installed with new belts... I guess Im in the wrong line of work as they only had the car there 2 hours and the parts cost for the pulleys when I called the other day was about $90 a pop - so I guess they are charging about $150 / hr for labor give or take... on the up side the s/n on the block matches the vin (I guess someone changed the dipstick / tube setup... they claim everything looks tip top under there and all the services were done on schedule since it was new.

Maybe I should go back to 60s mustang restoration for work if I can get the $150/hr (I never made that kind of scratch when I was doing that)...

Oh well - my beliefs are confirmed - never have a dealer work on your car unless you hit the lotto, someone else is paying, or its warranty work...