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bnhgf · Joined: 13 Jul 2020 Posts: 13

Hi, just completed the engine rebuild and put it all back together, but it seems that I’ve mounted the alternator somewhat wrong

I have mounting bracket with rubber dumper lying around not connected anywhere , and it should probably support alternator from the bottom.

The top alternator mounting bolt goes through two bushings (replaced with polyurethane bushings), and on the bottom I have a tightening bracket - the bolt goes through alternator and the bracket in the back. And the other side of bracket holds the bolt which goes into the crossmember.

The engine makes some squeaking sound when warming up. Maybe belt too tight, maybe related to alternator mounting . Water pump and alternator itself are new[url] https://youtube.com/shorts/TiikRUgyFXk?si=xRrEIcyLIFsPV5XI[/url]

copeina · Joined: 06 Dec 2023 Posts: 21 Location: Calgary, AB, Canada

I had the same thing when I replaced my timing belt/water pump/tensioner. It was a silly thing, but enough to squeal and even fill the garage with smoke. Totally thought it was the alternator and fought with that for far too long before taking a step back.

The tensioner pully gets adjusted counter clockwise. I initially did mine clockwise, and all looked great, but there was just enough interference on the block to not allow the pully to spin. Long story short, make sure everything is spinning before you go crazy with the alternator mount - it's a beast to get adjusted if you're working solo.

Hope that helps.
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1978 924 NA Project

924RACR · Posted: Tue Mar 18, 2025 12:00 am Post subject:

Agreed, sounds more like timing belt tensioner...
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
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Raize · Joined: 18 Sep 2013 Posts: 445 Location: Scotland

The alternator should absolutely not be bolted to the crossmember!

Don’t use your alternator as an engine mount please.

The rubber bobbin (about a 30x30mm one from memory) screws into a threaded hole on the engine block and then the adjustment bracket for the alternator is held onto it with a nut. Then the bolt goes through the bottom lug of the alternator into the slot of that bracket.