Alternator bracket bolt

[benedict_h]

Hi all,
Yesterday I noticed an unusual noise coming from the engine compartment. On inspection I found the alternator vibrating a little with the engine running idle. Closer inspection proved the top left bolt missing from the alternator bracket. The Parts Catalogue says it's a 5/16 UNF x 2" long bolt, one of three securing the alternator bracket to the cylinder head. As I could insert a tie wrap for 3,5 cm in the hole, I suspect the bolt to have snapped off.

This will probably mean retapping the hole in the cylinder head?

Any advice in terms of dos and donts? The alternator is still in place. Have done nothing so far but check the belt tension, which was 11 to 14 mm free play, and soaking all remaining bolts in WD-40 regularly.

Thanks in advance,
Benedict

[Mike’S-a-loon]

Hi Benedict,

the question is, are you going to try to remove the remains of the broken bolt or not?

it sounds like it may be possible to leave it where it is and tap out the 35mm of hole that is empty. You may choose to use a Helicoil or some other thread repair insert to bring it back to 5/16 and use a shorter 5/16 bolt.

If you want to try to get the broken bolt out, then frankly that sounds like a nightmare, especially with the head in place. Perhaps remove the head and see if a machine shop can help?

[benedict_h]

Thanks for your advice, Mike. Managed to secure a shorter bolt, which seems to hold. Will think of a more permanent solution.
Rgds
Ben