Crypty diagnostics- step two

[Tinster]

Carb Linkage 101 :

I removed the air filter canister and carb heat shields:

OK- I removed the folded piece of metal that connects
the two carbs. I disconnected the two choke cables.

What do you know! When I installed the front choke cable,
two weeks ago, the tag end twisted into the lever arm
opening and was the cause of the front carb throttle shaft
not rotating.

Both throttle shafts align up perfectly. See photo-
All the levers and shafts on the two carbs now move very
smoothly with slight finger pressure.

What is my next step?
Battery almost charged.

Thanks as always,

d

 

[tdskip]

So only one carb was getting throttle input Dale?

 

[Tinster]

So only one carb was getting throttle input Dale?

<span style="color: #006600">It appears that is the case on the morning of the breakdown after 3/8 miles driven.

I cannot believe I drove all over the place, even at speeds
of 75 mph, the day before if only one carb was functioning.

And I don't think that explains holding 4000 rpm (in neutral)
and then dying. Can one carb hold 4000 rpm? If so, why the very
fast death after 20 seconds or so?

But at least I fixed an unknown problem.
That's a good start.

d
</span>

 

[Tinster]

I re-installed the Ratco throttle linkage and the
bent metal center piece still appears out of wack.

Both carb throttle shafts appear to rotate in unison
and with no difficulty.

Have I made a blunder in my installation of the bent
metal center piece? I tried to get two pieces of bent metal
onto every round shaft piece.

thanks,

dale

 

[TR4]

Another non-mechanics view but can you get a longer center rod to help straighten out the assembly by getting it into the center part of the clamps? The one in the photo appears to be too short.

 

[Moseso]

That carb link doesn't look good, and should be straightened up -- but it doesn't explain your symptoms.

Given the "rich black" color of the plugs in your other thread, and your description of difficulty with the choke cable, I would look at all of the parts in the choke system. Running too rich is more likely to explain your symptoms.

 

[Tinster]

So OK!! Battery is charged.............

I reconnected everything except the choke cables.
Installed new fuel filter and new rear end fuel hoses;
just to be safe.

Without chokes-- the car started easily on 2nd crank.

Cold engine, rough idle at about 400 to 500 rpm.

Timing at 4* with vaccuum pipes connected to dizzy.
Engine died when vacuum hose was pulled off dizzy.

Intake manifold vacuum at steady state -19 pounds.

I could NOT push rpms over 800- the engine died.
I saw plenty of fuel in the in-line glass cylinder.

d

<span style="font-size: 14pt"><span style="color: #000099">all ideas welcomed </span> </span>

 

[Moseso]

Warm it up?

A cold engine with no choke usually can't be revved. It may start and idle, but will sputter and die if you try to rev it.

 

[tdskip]

Another non-mechanics view but can you get a longer center rod to help straighten out the assembly by getting it into the center part of the clamps? The one in the photo appears to be too short.

I agree Dale - in my TR's the shafts are all in a straight line. I'd like to know why the one shaft is at an angle.

 

[NickMorgan]

Dale,
I can only speculate from the picture of your linkage, but to me it looks as though the two connecting clips (don't know their proper name!) have bent as a result of the left hand throttle shaft not wanting to turn. If you imagine the throttle in the middle pulling down on the centre spindle, and the left spindle not wanting to turn, it could pull the clips like that.
Having thought about it again, the right hand spindle being stuck could have caused the same damage.
When the choke was stuck would it have effected the action of the throttle shafts?
Can you remember which plugs were sooty? If they were the front three or back three that would help your diagnosis. Without choke you need to let the engine warm up before it will rev, unless you open the throttle very slowly.
I have a hunch that one of your carbs was way too rich when you broke down.

 

[poolboy]

The actual throttle shafts do line up. It's the accordian spring link inbetween that's twisted, throwing the "ball-jointed" center link out of wack.
I agree that a warmed up engine will rev up better than a cold one, without a choke.
And, a stuck open choke will flood an engine and kill it in short order.
Just pull the choke knob on a good and warm engine and see how fast the engine dies.
I bet the whole thing started with a problem with the choke cable and it's adjustment. Maybe it just slipped from it's attachments and wouldn't shut off the choke.
Anyway in the Tropics, you shouldn't need it unless you need to make a fast getaway with a cold engine.
I know from April thru October I don't have to touch the choke to just start the engine. When my temp gauge starts to move, then so do I.

 

[Tinster]

I have a Ratco cable throttle assembly.
Perhaps this assembly looks odd because of that?

d

 

[Don Elliott]

From the way the throttle shafts are out of line, I`d say that one of the carbs has a different insulating spacer and if one is thick and one is thin, this would put them out of line. Fix this plus the suggestion above of a longer center rod. You should have about 1/8" of space at each end of the center rod. Look at my TR3A set-up.

 

[poolboy]

I have a Ratco cable throttle assembly.
Perhaps this assembly looks odd because of that?

d

I'd say the key factor here is, if despite having the center "ball-jointed" link out of line with the actual throttle shafts of the 2 carbs, are the carbs are in sync with respect to their ability to open both throttle disc equally ?
As far as putting the "bent" part of the clamp on the throttle shaft, as long as you have both parts on either side of the tightening nut on the shaft, that's adequate. It really doesn't have to slip on the shaft quite as much as you have it if it helps line the whole thing up.
Looks like the Ball part of the ball and socket could use a longer shaft, but if that can't be found, can the vertical link be moved to the right as in it looks in your picture?
But , like I said, the really important thing is if the shafts move in unison, despite the misalignment


You can check for synchronization in the usual manner with a unisyn or sthethescope at the air intake.
But, I believe that what actually caused that engine to die was associated with the choke situation.

 

[Tinster]

The two carb throttle shafts are in perfect alignment
and they rotate in perfect unison even though the middle
folded metal piece looks odd.

I'm not sure why the middle piece looks so odd.

In any event, all six spark plugs were new, gapped at .025
and they were a nice toasty brown before the breakdown.
All six were black, black, black when I pulled them after
the breakdown.

On we go......................

dale

 

[DNK]

CHOKE,CHOKE,CHOKE

 

[Silverghost]

Dale, compare your "clips" to those in the other picture, they are definitely in need of replacing. I can appreciate that everything functions smoothly, there is something just not right about that setup the way it is now.

 

[tomshobby]

In any event, all six spark plugs were new, gapped at .025
and they were a nice toasty brown before the breakdown.
All six were black, black, black when I pulled them after
the breakdown.

On we go......................

dale

Poolboy, recognize this? Exactly what happened to me on one of our trips this summer only I was able to limp it home. Also happened to Tarheel this summer.

 

[BobbyD]

Dale.........I don't know if it will help or not but here how my linkage looks. And BTW, when I first got my car I drove it for a few months and then discovered that only 1 carb was functioning. I had so much more power after the carbs were rebuilt!

 

[poolboy]

In any event, all six spark plugs were new, gapped at .025
and they were a nice toasty brown before the breakdown.
All six were black, black, black when I pulled them after
the breakdown.

On we go......................

dale

Poolboy, recognize this? Exactly what happened to me on one of our trips this summer only I was able to limp it home. Also happened to Tarheel this summer.

I need to spank myself, Tom. Do you want to throw that out...or should I ?