Lotus Elan

Alternator mounting bracket

PostPost by: 69S4 » Sat Apr 20, 2019 8:03 am

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.
Stuart Holding
Thame UK / Alpe D'Huez France
69 S4 FHC
Honda GoldWing 1800
Honda CBX1000
Kawasaki H1 500
Yamaha XS2
69S4
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1075
Joined: 23 Sep 2004
Location: nr Oxford UK

PostPost by: nmauduit » Sat Apr 20, 2019 8:43 am

There are stronger versions of bracket, specific to alternators, that may be of help

viewtopic.php?f=38&t=24554
S4SE 36/8198
User avatar
nmauduit
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1158
Joined: 02 Sep 2013
Location: France

PostPost by: 69S4 » Sat Apr 20, 2019 11:05 am

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.
Stuart Holding
Thame UK / Alpe D'Huez France
69 S4 FHC
Honda GoldWing 1800
Honda CBX1000
Kawasaki H1 500
Yamaha XS2
69S4
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1075
Joined: 23 Sep 2004
Location: nr Oxford UK

PostPost by: nmauduit » Sat Apr 20, 2019 12:21 pm

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)

l1110002.jpg and
alternator Lucas 17 ACR conversion
S4SE 36/8198
User avatar
nmauduit
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1158
Joined: 02 Sep 2013
Location: France

PostPost by: 69S4 » Sat Apr 20, 2019 1:24 pm

Any idea what the purpose of the strut up the side on the Ford bracket is - and where it attaches to on the TC?
Stuart Holding
Thame UK / Alpe D'Huez France
69 S4 FHC
Honda GoldWing 1800
Honda CBX1000
Kawasaki H1 500
Yamaha XS2
69S4
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1075
Joined: 23 Sep 2004
Location: nr Oxford UK

PostPost by: mbell » Sat Apr 20, 2019 3:02 pm

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.
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
mbell
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1378
Joined: 07 Jun 2013
Location: Austin, TX (UK Ex-pat)

PostPost by: Davidb » Sat Apr 20, 2019 3:25 pm

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.
'65 S2 4844
Davidb
Fourth Gear
Fourth Gear
 
Posts: 780
Joined: 02 Jul 2009
Location: Vancouver, Canada

PostPost by: 69S4 » Sat Apr 20, 2019 4:15 pm

mbell wrote: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.


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.
Stuart Holding
Thame UK / Alpe D'Huez France
69 S4 FHC
Honda GoldWing 1800
Honda CBX1000
Kawasaki H1 500
Yamaha XS2
69S4
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1075
Joined: 23 Sep 2004
Location: nr Oxford UK

PostPost by: Esprit2 » Sat Apr 20, 2019 9:38 pm

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.

http://gustafsonspecialty.com/welcome2.html

Regards,
Tim Engel
Esprit2
Third Gear
Third Gear
 
Posts: 325
Joined: 02 Apr 2008
Location: Twin Cities, Minnesota, USA

PostPost by: SENC » Sun Apr 21, 2019 12:35 am

RD Enterprises sells the Gustafson kit, it is what is on my S4.
Henry
69 S4
SENC
Third Gear
Third Gear
 
Posts: 384
Joined: 30 Dec 2015
Location: NC

PostPost by: 69S4 » Sun Apr 21, 2019 7:26 am

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.
Stuart Holding
Thame UK / Alpe D'Huez France
69 S4 FHC
Honda GoldWing 1800
Honda CBX1000
Kawasaki H1 500
Yamaha XS2
69S4
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1075
Joined: 23 Sep 2004
Location: nr Oxford UK

PostPost by: wotsisname » Sun Apr 21, 2019 8:58 am

I have a non OE bracket, from Sjsportscars I think... Just in the process of fitting this today.. hopefully starting the engine later.


img_20190421_095321539.jpg and
Alternator lower bracket. Not OE


img_20190421_095336807.jpg and
Side view


Pictures to follow
1968 Elan plus 2 - project
2007 Elise S2 [modified with a Hethel 70th sticker (yellow)]
2000 Elise S1 - Sold
wotsisname
Third Gear
Third Gear
 
Posts: 335
Joined: 24 Jun 2015
Location: Hertfordshire, UK

PostPost by: wotsisname » Sun Apr 21, 2019 9:05 am

This is a RHD, +2. PO had used the OE dynamo bracket with modified lower bolt.

img_20190421_093053877_burst000_cover_top.jpg and
Lower mount, fabricated type


img_20190421_093133561.jpg and
Side view
1968 Elan plus 2 - project
2007 Elise S2 [modified with a Hethel 70th sticker (yellow)]
2000 Elise S1 - Sold
wotsisname
Third Gear
Third Gear
 
Posts: 335
Joined: 24 Jun 2015
Location: Hertfordshire, UK

PostPost by: wotsisname » Sun Apr 21, 2019 9:15 am

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

img_20190421_093155894.jpg and
Alternator bracket


img_20190421_092711758.jpg and
Upper brackets, alternator


img_20190421_092823470.jpg and
Upper brackets 2
1968 Elan plus 2 - project
2007 Elise S2 [modified with a Hethel 70th sticker (yellow)]
2000 Elise S1 - Sold
wotsisname
Third Gear
Third Gear
 
Posts: 335
Joined: 24 Jun 2015
Location: Hertfordshire, UK

PostPost by: wotsisname » Sun Apr 21, 2019 10:00 am

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.
1968 Elan plus 2 - project
2007 Elise S2 [modified with a Hethel 70th sticker (yellow)]
2000 Elise S1 - Sold
wotsisname
Third Gear
Third Gear
 
Posts: 335
Joined: 24 Jun 2015
Location: Hertfordshire, UK
Next

Total Online:

Users browsing this forum: nmauduit and 9 guests