Hello
I have a 2005 G35 6MT with about 186,000 miles. It is rusty and was not maintained well by the previous owner.

I have had belt noise that goes away when the engine gets warm, since I bought it. I proactively decided to replace both the idler/tensioner pulleys since they were rusted and the AC belt was also really very old.

However, the AC pulley tension adjustment bolt was not moving at all, as though it had seized in place. Eventually I put too much manual effort in removing it that it sheared and broke

Can I replace it ? What is the bolt part number to purchase ? Can I also replace the other tensioner bolt for the main drivebelt since that is also rusty and I don't want it to seize up in the future ?

I have the full service manual, if anyone can point me to the pages to replace this bolt I can read it up. I could not find it in the EM.pdf file that describes adjusting the pulley.

Please advise what steps to take. And I do not want to do "AC delete". I love and need the AC in the summer.

Happy to share any photos if you want to see more detail.

Thank you

 

I think those belt tensioner bracket torque specs are in section MA - Maintenance.

You MUST loosen the nut in the middle of the pulley before the adjuster can be moved, this is usually why people break off the adjuster nut.

Here's the part number for the AC tensioner, 11925-AG30A

You can probably just buy them at a local parts house though, they're an extremely common design on Japanese vehicles. Toyota and Nissan both use literally the same bolt for the adjuster.

Or go to a pick-n-pull wrecking yard and pull one off a salvage vehicle.

Your primary belt adjuster is probably fine, just shoot the threads with some PB blaster and make sure to loosen that nut in the middle of the pulley before messing with the adjuster nut.

 

Also, when you replace these things you're just replacing the pulley itself, the bearing comes pre-pressed in. The adjuster nut and that little metal bracket behind it the nut goes through you keep. Just remove that nut in the middle of the pulley to get the bearing off, there will be some dust sleeves on the front and back of the pulley though, they face a specific direction (normally they're sort of cupped out away from the pulley) so keep track of the orientation and location of both those dust covers.

I also recommend using a pair of scissors if you need to cut the old belt off because the adjuster nut is broken. Using a utility razor is much more difficult and one time I slipped and slashed a lower radiator hose... a minor job turned into a slightly less minor job.

 

Hi cleric670. Thanks for the advice. I was actually following the procedure and loosened and took off the pulley nut first. However, I wanted to change the belt too so that's why I was moving the adjuster nut. I did not spray PB Blaster on it, and I did not think of cutting the belt out with scissors !

Anyway, I got both the belts off later that night, without damaging anything else. Just need to buy a replacement adjuster nut and go through the process again a bit more carefully. I have save the orientation of the dust covers and the washers that go on the pulley, and appreciate you mentioning that.

Thank you for the part number. I have a Nissan showroom a few miles away and I hope they have it, otherwise eBay or FB Marketplace.

Best

 

Just go to a local Autozone, Oreillys, Napa, Advance Auto Parts. I bet they carry those things in stock.

I also think it's the same adjuster bolt for both the AC and primary pulley. The part behind it is different but I think the bolt itself is the same.

 

For anyone wondering what the exact part numbers are for without the idler pulley and the bracket itself:
- Adjustment bolt 11948-AL50A (replaces 11948-AL500)
- Shaft 11928-AL50A (replaces 11928-AL500)