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TR6 TR-6 still not running right

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bigbadbluetr6

bigbadbluetr6

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I recently just rebuilt the carbs and have no tuned them yet. I have barely drove the car since and when I was driving it I noticed it wasn't idling smoothly but it was barely off. Today I went to an event about 2 hours away. On the way down we were driving 60-65. I could hear and feel the car have a slight hesitation. Kind of slightly jerky.

On the way home I came home on the Interstate running 75-80. The car seemed to like it and I didn't notice any of the previous hesitation. After running like this for a little over a hour the car started to miss. I would press in the clutch, rev, the motor and then put the car back into gear. That seemed to work for a while. The intervals were not that close of this happening. Then while close to home on the interstate it started to do this same thing but press clutch, rev and put into gear no longer worked. I got off the exit before I wanted to so I could limp home. After getting off the highway I stopped at a light. Taking off it stumbled continuously. Had to stop at the next light. Take off from that light and no problem. Once I get closer to home and a few more stop lights I take off from one light and the car instantly dies. Get it started and on my way than it shows that it is running on the tach but press the gas pedal and nothing. Have to restart the car. Same thing happens again and I pop the clutch like a roll start. Starts, Drive home the rest of the way and still have the slight miss.

Get in the garage and take the airbox off to mess with each carb separately. Here is what I found,
When giving both carbs a little throttle it looked like the rear carbs cylinder(don't know the name) moved a little bit sooner than the front carb.
At idle:
Rear Carb - I would hold the cylinder open and the car would die. I could moved the cylinder up and down smoothly.
Front Carb - I would hold the cylinder open and the car would still idle. The cylinder has resistance about half way up.
Suction at idle
Rear carb - I could feel suction
Front carb- Couldn't feel any suction
Cover the carb with a piece of cardboard
Rear carb - almost kills engine
Front carb - Keeps idling and maybe a slight increase.

Hope I explained this well enough. It is probably a simple solution. There also seems to be a whistle. I don't know if there is a leak in one of the carbs somewhere. I don't really know the correct direction to go into right now but I have a feeling I will be taking the carbs off the car but then I wouldn't have a clue on what to look for. I understand the carb needs air and fuel to operate and I believe it is air because I took the fuel line going into the carb while the car is running and it squirts out(both sides). This makes me believe its and air issue and that would be the carbs. I came to ask everyone here because you have probably seen this problem before and know the simple solution. Thanks in advance.
Eric
 
Sounds like multiple problems, to me. I'd try fixing a few of them, and see if the others become more clear.

First problem, I suspect, is not enough fuel delivery. Clogged fuel filter, or FOD in the lines. I had a somewhat similar problem recently that I now believe was body shop dust that had settled in the fuel line between tank & pump. Forcibly blowing air backwards through the line turned the fuel in the tank black.

Second, you need to look at why the pistons don't move with equal ease. You should be able to feel a definite resistance to upward movement throughout the range, but no binding. Kind of sounds like the damper on the rear carb is completely empty and the front is only half empty (but still too low for proper operation).

Throttles may be badly out of sync, but that has a lot less effect than you'd think on how the engine drives (it mostly affects idle smoothness).

Then you can look at why the mixture is so different between the two carbs. Leaky float valve, or perhaps a sunken float. The mixture adjustment on a TR6 is pretty limited, so I doubt you'd see that much difference from just having one full rich and the other full lean (but wouldn't hurt to look at that). You can just set them both full rich (adjustment fully clockwise) as a starting point.
 
Before I put my carbs back together I checked to make sure both floats were working properly. Once everything was back together and on the car I did have a problem with one of the float valves not working properly, took carb off and readjusted the float and no problems there I don't think. Going outside to look at your suggestion. Probably off the the parts store to get some full line.
 
Also I previously kind of mentioned this. When I cover the Rear carb and rev the motor there is a definite stumble. When I cover the Front carb I can rev the engine like there is no problem. Just some more info for the trouble shooting.
 
73 versions of the carbs sometimes (often enough) have problems with the valve that transitions the float chamber vent opening.
The 73 version only lasted that one year. In 74 it was improved and remained unchanged from that year on.
Check to see if it is functioning properly:
https://www.mv.com/ipusers/last/emissions/page_28.html
Closely observe the position of the lever and the plunger which it activates, both in the "IDLE" and "OPEN THROTTLE" positions.
 
HELP!!!!
The first pic is from the back 1/2 of the engine, 4-6. Second is the first 1/2, 1-3. Third is looking at the distributor top. The middle screw is brown color kinda like rust color.

The problem is I tried to get the car started tonight and it wouldn't start. The other day when I tried to get it started it wouldn't start very easily. I had to jump it with another vehicle.

Poolboy I haven't been able to get the car running but the carburetor vent valve does open when I open the throttle.

I am lost on what to do now. I haven't changed the fuel lines, which I need to do but I would think the car would start rather the lines are bad or not. The fuel pump pumps fuel. Any help would be appreciated. Thanks
 

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Looks like some flooding from the front carb.
Beside that, you should check to see if you are getting spark at all 6 spark plugs
 
I checked for spark last night and I have spark on all cylinders. This would mean my coil and distributor are working properly since they are providing spark to the plugs? I'm not sure how bright the spark should be. I guess I will YouTube a spark from a plug. The spark was a blue color which I saw was good. I checked the fuel pump and while cranking the car over it was pulsing fuel out of the hose to the carbs. After reading about mechanic fuel pumps this should be normal? The car still wouldn't start last night. Still frustrated!!!
 
You have spark; you at least have gas to the carbs, if not inside the carbs.
Are you pulling the choke knob all the way out ?
Try that, but keep your foot off the accelerator pedal.
If that fails to at least get the engine started, get a can of starter fluid.
Give each carb a brief shot.
If the engine fails to start and run for even a couple seconds, then I'd suspect the ignition timing is off.
If you can get someone to crank the engine while you rotate the distributor a few degrees clockwise and then counterclockwise to see if you can get the engine to catch.
 
How much spark should I be having? Constant? None of them fire at the same time. I don't know how timing could have got off or changed but I guess it could happen.
 
Try starter fluid..see if you get a response from the engine.
Take the air cleaner off. Lift the air valve with your finger, and give a brief shot of starter fluid into the space created when you lifted the air valve. Do that to both carbs and try to start the engine before the starting fluid evaporates.
You have described the symptoms. The idea now is to run some test in order to diagnose the problem..Once the problem is identified, someone can suggest a cure.
No.... the spark plugs do not fire at the same time.....The spark plug that fires is determined by the counterclockwise rotation of the rotor within the distributor and which spark plug wire it's pointing at.
 
So I sprayed started fluid into where the gas enters the carb and I also sprayed it when I lifted up the piston. First crank and the car fired right up. Still don't understand why it won't start with out the fluid. Oh well I guess since it started. Once I drove it for a while I took a picture.
 

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Let me see if I understand your post.
You were able to get the engine started with the starting fluid. Once the engine started, it stayed running and you took it for a drive ?
Is that right ?

AND, if so when you got home, were you able to restart the engine without staring fluid ?
 
Once I get the car started and warmed up it will start again no problem. Its just that initial start that is difficult. Don't make sense to me.
 
You say you 'rebuilt the carbs'. I'd bet there is something related to that. Possibly having to do with the starter box, the hollow disc inside and or the adjustment of the fast idle cam's engagement with the throttle stop lever.
Unless it's in the heat of the Summer, I usually have to fully engage the choke to start the engine, then as soon as it does start, I cut back on the amount of choke, using only enough to keep the engine running. After a couple of minutes, I usually have the choke completely off while I wait for the temperature gauge needle to begin to move.
Once it moves, I'm ready to drive off.
 
I don't understand what the start box is. I'm looking at a Vic Brit catalog. I think I took the cold start value apart. Maybe if I did do that I messed something up in there. I know I took the Bypass Valve Assembly apart and put new gaskets in it. That's about all I didn't besides clean the carbs. I didn't know what I was doing so I just did what I thought I should have done.
 
It's the same thing as the cold start valve. If you took it apart, it is possible that you put the disc back in out of it's normal position.
 
This catalog says the cold start valve is only for the 75-76 model. I would guess my 73's carbs would have something similar. I really don't remember if I took anything else apart besides the bypass valve.
 
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