Anyone got a picture or a dimensioned drawing of the mounting bracket for an alternator - the one that bolts to the block. I know it?s different to the original dynamo one but quite how different?
Background to this is that when I swapped to an alternator many years ago I adapted the dynamo mount, cutting and welding it to line up the pulleys. It?s worked ok - and still does- but when I was under the car yesterday I noticed the pulley alignment left something to be desired when viewed from underneath. I can also see the belt is wearing on one side only where it?s running out of line. The existing mount doesn?t have enough material in it to adapt it further so I?ll need start from scratch and fabricate a new one. It would be easier if I knew what the bracket looked like to give me something to work from.
Thanks for that link. I’d looked last night but for some reason hadn’t come across that discussion. There looks to be a few versions / designs of the bracket in existence with some of them looking seriously hefty. The one that SJ sells looks pretty much like what I made by cutting and welding the dynamo one - except it pushes the alternator an inch or so further forward, which is what I need.
If it works well enough for them to sell it then it’ll probably do for my purposes. Given what they’re charging and the 10 days it’ll take to get one from them atm I suspect I’ll spend an hour or so later on making one based on their concept.
I converted my street S4 to alternator when I put it back on the road a few years ago, and from discussions on the forum I opted for the strong bracket then - been happy with it so far (though only about 30 hours use, 40 tops). So I got the same kind for the white one I’m restoring, but unfortunately the parts are now stashed and it may take hours if not days to locate it for taking measurements… I understand mine is a Ford cast part, there are more or less equivalent repros out there (possibly event better)
Attaches to one of the timing cover through bolts. There’s also a load spreader plate that links the three bolts on the timing cover in that area, as known for it to snap one off with out the plate.
When I fitted an alternator to my S2 I used the original dynamo bracket. The front lug of the original bracket my have needed a washer as a shim but other wise the pulleys lined up-then I put a brace from the front of the alternator bolt to a timing cover bolt. It is very firm and hasn’t needed adjusting in thousands of miles.
I’m surprised you’d want to spread load from what looks like a fairly robust mounting area on the block into a fragile alloy component - even with the load spreader plate. But then I’m not I’m an engineer so what do I know.
I did hope I might be able to do a direct swap and use the dynamo bracket directly but there was no way the alternator (45ACR) would fit. Not only were the bracket ‘ears’ in the wrong place fore and aft, they needed to come out further from the block otherwise the alternator wouldn’t swing inwards enough to get the fan belt on. A bigger fan belt had it swinging so far out it hit the chassis. That’s when I started cutting and welding.
Gustafson Specialty, the same company that converts Nissan geared starters to fit the Twin Cam, also has a complete alternator conversion kit for the Elan.
Their mounting bracket looks exactly like what I modified the dynamo bracket into but with the block mounting holes further to the rear. The dynamo bracket is too short to drill further back and it?s going to be easier to start from scratch than modify it again. Knowing where the mounting holes are in relation to the ?ears? would save a lot of trial and error. Anyone got one they could measure? All of that assumes that alternators are much of a muchness in terms of size, something I suspect isn?t the case.
Apologies, pictures aren’t the best… Using a phone (quicker). Another picture of the lower bracket and the upper brackets for completeness… the lower bracket is probably a lot easier to fabricate than the others shown… I have no idea on reliability of these.
HTH
Adrian
I have an old Lucas 15ACR (TR5/GT6 ?) And a modern 17ACR equivalent on my bench. The lower mounting brackets are certainly a different spacing… Approx 6mm wider for the modern unit. I guess the split tube in the rear mounting would take some of that but assume a packing piece would be a better idea.
Thank you very much for all of that. It’s exactly what I need and as soon as I finish painting the kitchen I’ll see if I’ve got the raw materials to start on making a copy.
Re the picture with of the upper bracket with the reinforcing strut - very useful. For some reason I had in my head that the strut went at the front of the cover. Seeing it in situ has saved me from trying to cobble something together that was never meant to go there.
Hopefully I have it assembled correctly… I should have it all together later today. To check alignment, etc.
I vaguely remember reading that you have to be careful with the lengths of these bolts into the engine block… hopefully others will know… with this bracket it looks like a normal hex bolt will fit, the dynamo bracket had a half height head… I guess a socket head would be a good idea.
Stuart - here are pictures of my mounts in use then a few measurements - if all goes well I might get the engine out after Easter services and can get better pics and measurements, but this may get you started.
The small Denso alternator can be found at a pick-a-part from a Metro Geo, or a Suzuki Swift. If you choose that route, you can grab the plug from the wiring harness that goes into the back of the alternator. Mine for the S2 came from that source, and has been going strong since 2006. Welded up my own brackets, similar to the one shown above.
I used the Nippon Denso alternator also-they are available on ebay although I bought mine quite cheaply from the local supplier.
I used the front lug only of the dynamo bracket and made additional braces from steel strap to secure the front of the alternator-it hasn’t shifted since I fitted it 5000 miles ago: