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TR2/3/3A Three TR3 questions

Jim Lee

Jedi Trainee
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Hi all,

I have just got my black beauty 1959 TR3 back on the road and it is running better than ever. I've got three questions though that I am sure someone with more experience than I will help me with.

1. There is some 'slop' in the accelerator linkage. For example, I will set the idle at about 8500 rpm, ride around for a while and when I get back to my garage my tachometer tester can show as high as 1100 rpm. If I reach over to the top of the linkage closest to the carbs I can get it back down to its original 8500 idle by giving it a firm twist counter clockwise, towards deceleration. It will stay there for a while even if I 'goose' it a little sitting in the garage but after a ride it will creep up again. I recently removed my carbs and the linkage and everything looked fine. When I put it back I made sure that I turned the screws that hold the linkage together so that they are firm. Not too long ago I replace the one and only accelerator spring that I can see so it is relatively new. My first thought is to get a strong spring but that would have to be a very strong spring to be equivalent to my manually twisting the linkage to get it back to my desired idle. I would just set it to the 'higher' idle and just not twist it manually at all but it is not possible sometimes to get the idle low enough doing that.

2. Dwell shows as 65 degrees. Before it was showing about 55 degrees. In both cases it runs as well as I can tell.
Is 60 degrees what it should be set to? I looked all up and
down my Bentleys and Haynes I could not find any spec for dwell. Did I miss it?

3. What is too cool for the engine to be running at? I used to have the needle almost exactly at the 185 degree 6 0'clock position but now it takes a while for the needle to get just a few degrees above the tick mark before 185. It will get up to 185 after I shut it off and let it sit there after a run but with my new infrared Thermometer I have yet to see a temperature above about 153 degrees on the block of the engine. This is after a good 20 minute run idling and sitting in my garage. The engine of course measures differently at different locations but should I be alarmed that it is measuring that low? I have replaced a good thermostat and tested them both using the pot of water on the stove technique and both worked exactly as advertised.
The thermo that is in there now is the hottest one I could find, 190 degrees.

Thanks very much,
Jim Lee
 
1) I had the same problem on my '59 TR3..it was worn throttle shafts. I tried EVERTHING to fix it...nothing worked..it nedeed new shafts (or bushings).

2) Set the point gap at factory specs and the dwell will take care of itself.

3) Be glad it's not overheating. Those new fangled thermo gauges are neat but you'll drive yourself crazy trying to fix these old rides with new tools designed for modern cars. If it's anywhere near 180 degrees you're OK.

We used to repair these cars with basic tools...no dwell meters, no"scopes", no nothing. They ran fine. Keep your sanity and keep it simple!
 
1) The idle will choose itself over anything that you will /can do to try to correct the problem. It's not a problem. Let you TR have a little fun doing what it wants to do. Tuck your toe under the gas pedal and pull it back. But also check the ball joints in the 90 deg. links for the throttle rod ends. They may have worn oval. Check that they are lubricated too.

2) I never tuned my TR3A in 49 years with any instruments. I always drove it to test it and if it was sluggish, I advanced it bit by bit by turning the vernier on the distributor. Then I would eventually find that it would start to "ping" at which time I would back off on the advance vernier on the distributor and it would run fine for the next 5 to 7 years.

3) I finished the restoration of a TR3A last June and the needle read over 235 degrees F. We cheched the temperature with a thermocouple in the radiator fill header and found it was really 185 deg. F. So we took the bezel and glass off the TEMP gauge and bent the needle over to read 185. That fixed it.

Don Elliottt, Original Owner, 1958 TR3A TS 27489 LO

https://mysite.wanadoo-members.co.uk/trebor/don3a_big.JPG
 
On the throttle return-- I made sure the carpet was clear (it wasn't completely) and I did put a better spring on the throttle return. That made a big difference in the idle return but not completely. I use Don's "toe" method to drip it the last 200 RPM if I'm idling for a while.

I'd like to have your too cool concern problem-- that's the next thing for me to finish fixin' this spring.

I've learned to use the little knob on the distributor, too and watched a BR car mechanic with 30 years experience set the point gap in seconds and never put the dwell meter on. I've done the dwell meter thing several times with no better results.
 
Don Elliott said:
1) The idle will choose itself over anything that you will /can do to try to correct the problem. It's not a problem. Let you TR have a little fun doing what it wants to do. Tuck your toe under the gas pedal and pull it back. But also check the ball joints in the 90 deg. links for the throttle rod ends. They may have worn oval. Check that they are lubricated too.

2) I never tuned my TR3A in 49 years with any instruments. I always drove it to test it and if it was sluggish, I advanced it bit by bit by turning the vernier on the distributor. Then I would eventually find that it would start to "ping" at which time I would back off on the advance vernier on the distributor and it would run fine for the next 5 to 7 years.

3) I finished the restoration of a TR3A last June and the needle read over 235 degrees F. We cheched the temperature with a thermocouple in the radiator fill header and found it was really 185 deg. F. So we took the bezel and glass off the TEMP gauge and bent the needle over to read 185. That fixed it.

Don Elliottt, Original Owner, 1958 TR3A TS 27489 LO

https://mysite.wanadoo-members.co.uk/trebor/don3a_big.JPG
I LIKE the way you think....
 
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