TR4 & TR4A Forum

Well, my generator is shot. Bad front bearing which caused the commutator to hit the windings, they are now shorted to ground. SO, instead of rebuilding or buying a rebuilt generator I’m thinking of swapping it out for an alternator and converting the car to negative earth.

I know that Moss sells a conversion but it’s pricey. Has anyone done 5is the old fashion way by sourcing an alternator that can do the job with some modification to the mounting? If so, please share what you did and pictures or links to a resto website would be really appreciated.

---

67 TR4A Project “”Lilblue”
72 TR6 “Lilred”

SPJSOTC

Gm alternator is very common. Both my cars are generator cars. I have about 15 spare generators if you want to go that route. 78 Ford Fiesta Bosch alternator fits the plugs on some of the tr6 cars. Kyle

Lou

Do a search using "TR3driver". He has posted quite a few articles on converting his Tr3's to alternators.

I have used some of his advise. My Tr4 is a long way from running, have installed a Tr7 alternator and the pulley fit without modification. Also note that you may have to do a jumper line on your ammeter if you choose a high amp alternator. In one of his articles he explains how to do this compared to the amperage of the alternator you have chosen.

Red

Guys,

Thanks for the replies. I will try a search but not quite sure how to do one here yet.

I am aware of the Fiesta alt (13107) on TR6s and the parallel wire to handle the current as I have a Bosch 55A on the 6 with a parallel 8 gauge wire but the mounting set up on the 4A is different. Not really worried about the plug as I don’t have one there now. I’ll keep the spare generators in mind worse comes to worse but I do want to get rid of the outboard voltage regulator while I’m at it.

---

67 TR4A Project “”Lilblue”
72 TR6 “Lilred”

SPJSOTC

Lou, you can add the alternator and rearrange the wires inside you voltage regulator and leave all the wires in place.
If you can't find the writeup, I'll have a look.
We used the GM one and your biggest issue will be the radio. Some have plugs that you reverse to change it to negative.

---

Wayne
1970 TR6
2000 Jaguar XK8
1949 Triumph Roadster 2000
1978 Spit6 (getting all the good GT6 parts, all poly suspension and Spax shocks)

Hi Kyle,

I like generators and have rebuilt 2 for my cars plus several more for others. Anyway, a guy on British Car Forum is looking for a date-appropriate C39 for his TR3 built in Feb 57. I only have a 1959 but can put him in touch with you if you have something.

Along those lines, I read somewhere that the Lucas date stamp was 'Week Year'. I've noticed that I haven't seen a Lucas generator stamped with any 'week' higher than 11, at least not until late 60s year dates anyway. Do you know if the date stamp is really a 'Month Year"?

Jeff

Thanks Wayne,

I am not concerned with the AM radio, if I put one in it will be a more modern version with USB stick capabilities. I don't mind leaving the regulator in to preserve the look but would bypass it as you said. It sure would be nice to find a small Nippon Denso or Delco replacement that can accept the 5/8" pulley and fit & operate on the current mounts with minor mods.

Lou

---

67 TR4A Project “”Lilblue”
72 TR6 “Lilred”

SPJSOTC

I did the Delco 10SI conversion, but with the thin belt. You can buy pulleys to fit for the fatter belts. Just google wide pulley for 10SI alternator. There are several on ebay.

Wide 10SI Pulley

I made up a lower bracket to hold the alternator pivot foot. I didn't have to trim the Delco foot as is mentioned in some write-ups. The pulleys lined up OK. I don't have any detailed pics of the lower bracket, but here's a couple of the alternator installed. I used the original adjusting arm, but I did have to use a spacer between it and the water pump housing.

---

Art


Beer is proof that God loves us and wants us to be happy. - Benjamin Franklin



Edited 1 time(s). Last edit at 2021-01-15 01:38 PM by ArtL.

I installed a GM alternator on my TR3 that has a TR4 engine and I did NOT like it. It pulled the motor power down and it took up so much space I had a really hard time getting it aligned. I took that off and went to a small Denso alternator and it is really good compared to the GM. I went with the Moss thin belt conversion so I would not have to contend with those big hard stiff wide belts.
Bob

Thanks for the replies guys. Bob which Denso model did you use? Might consider the thin belt conversion as well, not a lot of room to get that 5/8 belt past the support.

---

67 TR4A Project “”Lilblue”
72 TR6 “Lilred”

SPJSOTC

Lou - Art

Just a couple of comments

Lou.

If you look at the top heading you will see a "Q Search". Click on that. It will take you to a search page. If you scroll down a bit you will see "Advanced Search". Click on that. This has two areas of search. By subject and member. If you type in " Alternator and Tr3driver", you will be able to see everything he as written on the subject.

Art

My arm is like yours, with the exception of the spacer. I found that by mounting the arm on the back side of the top flange of the alternator I did not need a spacer and mounted it straight to the water pump housing.

Red



Edited 1 time(s). Last edit at 2021-01-17 06:36 AM by Reddragon.

BPNW has a look alike altenator that looks like original. It puts out about double (42?? amps) what the original generator does. Price is good and it looks original. I have it on my car but my car is still being built so I do not have running experience with it. Check it out it has also a built in regulator so you do a bypass in the regulator which they give you instructions for. I also did the thin belt conversion (from BPNW) for easy belt changes on the road. Bruce



Edited 1 time(s). Last edit at 2021-01-16 08:21 AM by bammons.

Red, I tried that originally, but the arm didn't quite line up. I would have had to put a slight bend in it. Might have been easier to bend it, but I was working at the time and the spacer was a five minute job.

---

Art


Beer is proof that God loves us and wants us to be happy. - Benjamin Franklin

I just happened to see an episode of “Wheeler Dealers” in which a TR4 was featured.
The generator was swapped for alternator and it appeared to be a very simple project.

Moss sells a complete kit that has every thing you need. Pricey. So does British Wiring, less pricey: https://www.britishwiring.com/product-p/ltr3tr4alt.htm

I opted for a small belt setup and used a Delco CS130 alternator which is a bit more compact than the older Delco alternators: https://www.hemmings.com/stories/article/delco-cs130-alternators
A friend made a spacer for the bracket.

The CS130 uses a later style pig tail. The one I got was sold as a "one wire" setup, which makes things very simple but also leaves you without an ignition lamp. Removing a silicon plug allows you to use the four wire pig tail so you can wire in the ignition lamp. The picture below shows mine when it was still a single wire. After I inadvertently left the key on (no ignition light to warn me) and fried the battery and the coil so I installed the pig tail.



Edited 1 time(s). Last edit at 2021-01-17 01:29 PM by andy303.