1500 Alternator conversion woes

[bigjones]

Hi folks,

Hope all is well.

Here's a $30 alternator from Advance Auto. All looks well.

However, the bottom bolt (Grade 8) keeps snapping in two. This is the 3rd bolt I've gone through in not many miles.

As you can see, in order to get this particular alternator to fit, it has to be installed upside down. The lower clamping lug does not straddle the lower mount, as does the Lucas. There's the problem I think.

Is there a solution or do I need a different alternator (if so, any suggestions - don't say Lucas, they are over $100)

Cheers!

 

[SilentUnicorn]

I like the Bosch 13107 Bolts right up and all you have to do is swap two wires in the original alt plug.

Lots of info here in the search function

https://www.britishcarforum.com/bcforum/u...e_Re#Post615896



m

 

[Guest]

I can't see the nut and broken stud in lower lug. YOu mean the small lug broke off the alternator? That's a 7127-3 (GM '73-~'87). It's designed to mount the other way around. Big lug at the bottom.

 

[bigjones]

m,
Thanks for the link but I think that discussion was for the 1275's etc, not the 1500 engine.

Kellysguy,
Yeah, sorry about the poor quality of the photo. I'll take another one tomorrow. What has been snapping in two is the lower bolt. This time it left half the bolt still in the alternator lug. Yeah, I installed the alternator upside down but that was about the only way it would fit, with the smaller of the two lugs down below.

Cheers!

 

[JPSmit]

When I did mine (1500 Delco) I mounted it right side up, and made two brackets that looked like this. I then

 

[JPSmit]

I then mounted one on each end of this

 

[JPSmit]

and the other ends to this - shimming them parallel with washers.

 

[JPSmit]

I then tightened up the top as normal - and managed to make my original bracket from water pump to bolt fit - if this doesn't make sense I can post pics tomorrow.

BTW I made my brackets out of the cut offs from the chrome bracket I bought to hold the top in place before I realized I didn't need it.

 

[JPSmit]

OK just looked and found the pictures - here hope it makes sense

 

[bigjones]

JP,

Many thanks for a most excellent description.
Fortunately, I never throw anything away so I have that hack-sawed off piece of chrome somewhere.

Cheers!

 

[bigjones]

JP,
In that first photo.
There is the chrome bracket and under that there is a cast iron thing.
Where did that cast iron thing come from?
Cheers
PS Here's the broken bolt in the lug hole:

 

[JPSmit]

JP,
In that first photo.
There is the chrome bracket and under that there is a cast iron thing.
Where did that cast iron thing come from?
Cheers

it came with the car.

seriously, I THINK it was part of the bracket for the air pump before it was removed. I seem to recall it being attached to the bolts that attach the timing chain cover to the metal backing plate - it was behind that. Sorry I can't be more help than that. just went into the files again -you can see it here

 

[bigjones]

JP,
Thanks for that info.
I took the air pump off many moons ago so then I should have that bracket around someplace.
Cheers!

 

[Morris]

Another way to to the job is to cut the upper piece on the alternator mount-a-ma-jig flush with the front engine cover, then flip the alternator over and run a big long bolt through the original mount hole on the alternator and the hole you just cut off. Finally, you drill a hole in the long chrome tensioner bracket, put a few washers underneath it, and bolt it to the upper driver's side bolt on the water pump housing. You can now use the original tensioning flange on the alternator.

I am sure without pictures that makes absolutely no sense whatsoever.

 

[bigjones]

Morris,
Do you mean cut this off:

Cheers

 

[Morris]

That's the one.

I was able to source that part from an early Spitfire engine. The alternator mount on the early Spit... or at least the one I laid hands on... does not have that big honkin' protrusion sticking out. So that may be another option for you if you live near a junk yard full of Spitfires. :wink:

But if not, cutting that part off should achieve the same results.

 

[bigjones]

Well I found the air pump! It did not have that small cast iron piece but I managed to used the bracket and spacers to mount the alternator - works great!

Had to grind a bit off to accomodate the fan:

Cheers!

 

[JPSmit]

woo hoo!!!

 

[Morris]

Great work!

 

[jlaird]

Looks good from here, but then I am a long way from anywhere.