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TR2/3/3A Generator and other Odds

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CJD

CJD

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First of all, I have decided that Triumphs can never be completely perfect. They enjoy having one item in need of repair at all times. More on that later. This thread is about dynamos, or generators.

I pulled the generator yesterday for another rebuild. If you missed my rant on junk parts supplied by the big 4, then you know that all the vendors are supplying rear generator bushings with more than .010" clearance, which is just way to much! I have known this is an issue for 6 years, but as with most of us, chose to live with the problem. This particular generator, though, decided IT didn't want to just live with it, and began to protest with the horrible buzzing. It waited to act up until I had finally repaired the leaking gas tank (another vendor nightmare).

So...this rebuild had a couple goals. First, I was going to replace the yoke (outer housing) with one with the correct part number and date stampings. The date is 2 of 55. My car was built around march, so this yoke was about right to make it "number matching". Goal number two is to replace the wallowing "new" bushing with one that actually fit. I managed, about 6 months ago, to find an NOS rear plate for the generator:

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I didn't need an entire plate, but I had hope that an original Lucas plate would also have a properly fitting bushing. Fortunately, it did!! The rear bushing clearance dropped from .015" clearance to only .001". Now we're talking! I swapped the front plate, while also replacing the new ball bearing just in case it was damaged from the buzzing, and even swapped the field windings to the number matching yoke. I only had one odd issue in the rebuild. Considering I was re-using the field windings and armature from the same generator that was in the car. you would think it would drop right in and work the same. That didn't happen!?!

SO, this is one for Randall...

The rebuilt generator, same windings, same armature, put out no amperage when installed!! I jumped the field and it worked perfectly, so not the generator. It turns out all I had to do was tighten the voltage regulator screw 1/2 turn and everything came to life. How weird is that?? I figure the earlier yoke must not be as efficient magnetically as the later 1958 yoke I replaced?? Either that or the tight bushing centered the armature better so it was farther from the field windings?

I'm not worried...just curious how a new yoke would affect the voltage regulator setting??

Back to the quirks with Triumphs. As soon as I repaired the generator, the starting solenoid started to act up. I mean really? These cars insist on attention. I will fix the solenoid, and then the next, and next...until it finally gives me some problem I can live with. Maybe an oil leak or such. Then I will live with it in total equilibrium. As long as ONE item is not working right, a Triumph is happy. Once I have that one problem as one I can live with...I will be happy too.

In closing, the moral of the story is thank you to those souls who hold on to the ancient OEM junk, so we can have decent NOS parts on occasion!!
 
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CJD said:
I'm not worried...just curious how a new yoke would affect the voltage regulator setting??
Click to expand...
I really doubt that it did; more likely a bit of dirt or oil on the contacts. My suggestion is to remove the armature to dress and clean the contacts, then set the armature gap (2 gaps on the earlier RB106/1 boxes), then check the voltage adjustment with the cutout contacts blocked. All in the workshop manual (although in the wrong order IMO).

IMO it is possible to get everything working at the same time and staying that way; but it is definitely an iterative process. My old 3A was dead reliable by the time it got wrecked (although it did have a Ford alternator since the stock generator was simply not big enough for my needs). But I haven't gotten there with my current TR3 yet.

It is definitely a high maintenance car though, as was the accepted standard back then. There is a good reason that the service intervals start at only 250 miles! And in my limited experience, the regulator contacts will need dressing and cleaning every 20,000 miles or so (which the book calls simply "long periods of service" :smile: )
 
I do have too many kids. One sacrifice may be worth a well running Triumph!

Randall, I didn’t think about dirt on the contacts. I’ll give them a cleaning and see if the voltage jumps back up!
 
John,
As you know, I took every single part of my TR3 apart. My idea was that any and all seals, bearings, hoses, consumables etc would be replaced with parts that are of better quality than when these cars were new. My thought was my car would be 'brand new' when finished and as reliable as any other 'brand new' car on the road. I was wrong.

My car seems to always have at least one nagging thing remaining on the never ending list of things that need attention. After I rebuilt several generators, and installed an alternator (twice), I think I have the electrical portions working as expected. After the wheel bearing fiasco, I have a new issue. I soaked the inner seal with oil as the instructions suggest. Oil is slowly seeping out of the seal, and after any hard braking, I smell the oil burning off the pads. Every 6,000 miles, almost like clock work, I develop a miss at about 2500 RPM, that I've found to be fixed by removing and cleaning the spark plugs. My headlamps have yellow-brown spots in the center. I had a tail lamp burn out, and was surprised how much brighter the new one was compared to the old, so had to replace the other as well. I've only put 20,000 miles on it and have already had to replace the clutch, fuel pump, wheel bearing, generator, alternator... my tires are worn and I'm constantly having to stop to add gasoline.

To me, the definition of life involves constant change. Our cars are alive. They need to be driven to stay that way, and driving them causes them to change. Not driving them causes them to change in a different way.

Enjoy the life you've created.
 
Several years ago when my 3 was about completed, I was talking to a guy at a dinner and told him of my project. He said 'when you get done with a Triumph restoration you can just start again'. It's what we do. I had no major repairs over last season.
Bob
 
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