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Stromberg 175CD

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I added a couple more shots to the previous link. Not sure they help much as it is tough to get a good picture.

Longer bellcrank leg, however, is connected to the short rod, and shorter bellcrank leg is to the long rod. I bet that's your problem.

Also, rough dimensions long rod 14 7/16" edge to edge
short rod 3 3/8" edge to edge.

Randy
 
Thanks Randy, those shots are good. I will check the dimensions tomorrow.

I appreciate your patience on these ongoing questions. The car came out of the barn without a head, so I didn't have a starting reference point to work from. While I had it running, I have never been that happy with the throttle setup, so I now want to get it right.

The bellcrank mounting bolt fits quite well so rotational movement is good, but as it is a shouldered bolt the gap under the head results in at least 1/8 inch lateral movement at the end of the long leg (side to side, towards engine and back). It causes a dead spot while the slack is taken up. Do you, or anyone else, have that much lateral movement?

Also, how tight should the turnbuckle end screws be tightened around the rod joint connecting balls (Moss drawing item 86a)? They are spring loaded, so I don't know how tight to go; presumably you don't bottom the spring, or do you?
 
Ian-

No problem at all. I think you are missing the washer that goes with the bellcrank - part 88 in the Moss link Phil mentioned. It goes shouldered bolt - bellcrank - washer - manifold. That should take some slop out but it does not eliminate it completely based on a spare TR4a manifold I have. Washer is 1.5 mm thick on the manifold I have,but probably any reasonable washer will do.

Not sure about the 'how tight' on the end screws, but I think they are tight enough that you don't feel any slop, but loose enough that they move fairly easily. Hard to quantify, but you don't want them too tight so they bind when you work the linkage.

Randy
 
I have the washer. The shouldered bolt "shoulder" is slightly longer than the bellcrank thickness (so that it doesn't bind), but as the bellcrank rotates around the bolt head it wears a groove that effectively makes the shoulder stick out more so more lateral slop is possible. I am going to look for a thin shim washer that will fit over the shoulder and take up some of the slack without binding it up.
 
Good news and bad news.

I took a brake line copper washer, filed it down to about 10 thou thickness and put it between the bellcrank and the original washer. This took out the slack while still allowing the shouldered bolt to bottom properly. I now have a nice smooth acting bellcrank with a very small amount of lateral movement. The adjusted linkage allowed the idle to settle back to 600RPM nicely.

I took it for a test drive on a country road and just before a series of s-bends I lost throttle control and the engine wouldn't rev. Once the speed bled away the good low end torque kept me going at about 20MPH around the bends for about a 1/2 mile until I could find a driveway to pull into. Luckily nothing was behind me. I found that a control rod ball fitting had sheared and the long rod had disappeared. I either overtightened the end screw or it was weak and a throttle linkage without slack was finally too much for it. Luckily I had another rod at home which was brought to me by the cavalry (with a smirk on her face). It required some MacGyvering as it was a smaller diameter to the original.
 
Ahh, MacGyver is a very good freind to have around at times. Good news about the washer too. Drive on....and maybe borrow someones metal detector to scour the trail for the original rod.
 
Yep, losing the rod is a lot better than having it bind wide open going into those curves!

Randy
 
TR4nut said:
Yep, losing the rod is a lot better than having it bind wide open going into those curves!
Click to expand...
I had that happen back in the day with a Mark 1 Cortina 1500GT. High humidity day, cool temps, long straight country road, about 75 MPH and the carb iced up. It didn't want to slow down and a sharp bend was coming up; instant thoughts of dead mans curve. Couldn't knock it out of gear as it would probably have revved way past the red line, so I had to turn it off and grimly hang on as I found that it handled a lot different in that condition.

With this I discovered that there are 2 types of long rods. A thin one with one adjustable end and a thicker one with 2 adjustable ends. I am surprised that there aren't rigging instructions, or guidance on how tight to setup balljoints, in the manuals.
 
So I discovered, in another thread, that I am missing the gas pedal return spring? How does it compare in size and tension to the one on the end of the cross shaft in the engine bay?
 
The spring in the engine bay is the gas pedal return. There is no other, at least not on my TR4.
 
Ian:

I have just been restoring the pedal assembly on my 1962 TR4. There is a spring between the pedal and the "pedal box". It is quite stiff.

I will post some photos tonight when I get home from work.

Matt
 
Next part of this multi-part thread on my carbs.

I have one air valve that drops nicely down after being lifted, while the one in the back carb hangs up a bit. I have found that different amounts of torque on the 4 cover bolts dramatically affect its sticktion. It is perfect when one side is fully tightened and the other side has loose screws. The same happened with a spare air valve, needle and cover that I have. The needle appears to be straight so I am presuming that the jet or the mixture adjusting assembly is mis-aligned. Any tips?
 
TR4 said:
There are 2 springs attached to the pedal box for the brake and clutch pedals. No additional springs for the throttle pedal.
Click to expand...

Of course Phil is right ... I wasn't paying attention. Ian, I thought you were talking about the pedal return springs on the brake and clutch pedals. On the throttle there is only the one return spring.

Matt
 
Ian-

Wouldn't be surprised that you need to centralize the jet on the rear carb to get the damper to slide freely. On these carbs you have the bottom adjuster to allow that - can't remember the exact 'how to' but it is in Haynes or the factory manual. For me I slowly tightened up the adjuster with frequent checking for free motion of the damper.

Randy
 
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