New Carb (probably) problem, on the trail...

[Pighead]

Coming down Big Sluice on the Rubicon, suddenly won't hold an idle. But, only with the nose pointed downhill. Won't start cranking the starter, but will start if I put it in gear and crank the starter. I can keep it running with some throttle, not ideal when trying to crawl.
Uphill it runs fine, same on level ground. Been running fine for the first part of the trail. Sudden onset. Bad me did not check the porthole while it was occurring. Idling on level ground gas level is midway as it should be. I've been down this Sluice before, never had this problem.
So, clogged idle orifice that I can clear with a wire bread bag twisty thing? Take it apart and look? I've got a few days...

 

[brian]

Give it the ol rev to the moon then cover with a gloved hand trick.

 

[Pighead]

Give it the ol rev to the moon then cover with a gloved hand trick.

I like that one.

 

[charliemeyer007]

I would try setting the float on the low side of 1/2 way

 

[Gotta40]

fought weird idle issues on our 74, til I ended up putting a new needle and seat in it.

 

[Pighead]

I would try setting the float on the low side of 1/2 way

Hmmm...perhaps half a bowl of fuel, when tilted at an angle might push the float up high enough to shut the needle valve?

 

[charliemeyer007]

I like the idea of checking the condition of both the needle and seat while lowering the float a little. I'm thinking steep up up/down hill might be allowing fuel to spill over.

 

[Pighead]

Think I'll look at the plugs first, see what they say. Tomorrow.

 

[charliemeyer007]

Look at the contacts inside the distributor cap, aluminum ones build up a layer of oxide which is an insulator. I scrape it off with the small blade of a swiss army knife.

 

[Pighead]

Look at the contacts inside the distributor cap, aluminum ones build up a layer of oxide which is an insulator. I scrape it off with the small blade of a swiss army knife.

Well, I'll look at them, but last month I cleaned 'em with a wire brushed dremel...

 

[Pighead]

Pulled the plugs, they look wet, except for #1 & 6. I had started the engine, just to listen to it, it sounded a little rough, but I'm at altitude and I didn't really let it warm up...

 

[Pighead]

Swapped in a set of clean plugs, checked the timing and it sounded smoother. So did the ol' rev it to the moon and cover the carb with a gloved hand trick. Funnily enough, the float bowl suddenly filled to the top...guess I will be checking that needle and seat. When it stops raining.

 

[Pighead]

So, full float bowl and did not run well at all. Float bowl did not empty to normal while running...
Drained the float bowl, introduced my precision percussion tool to the needle valve area of the carb. Started it up and it ran well with fuel level midway up. Repeated the gloved hand trick and the float bowl filled again but returned to normal when started.
Hmmm...

 

[Pighead]

Took the top of the carb off, didn't see anything terrible. Needle & seat looked good enough. Float bowl not too filthy, so I put it back together. Runs fine.

 

[Pighead]

Took it for a drive, found a fairly steep spot. Nosed into it. Engine died. Fuel level about 3/4 of the way up the window. Re-started ok and drove out. Perplexed

 

[charliemeyer007]

I don't think it will run well with the fuel level that high. Wet plugs says rich perhaps spill over of fuel. See if the float works freely - maybe its binding a little on a burr or bent shaft, out a line tabs sort of thing.

 

[65swb45]

Get rid of that fawking rubber-tipped needle. RFG and rubber tip don’t play well together.

 

[numby]

Repeated the gloved hand trick and the float bowl filled again but returned to normal when started.
Hmmm...

Also known as the Redneck Rebuild. It doesn't take a very big piece of crud to block some carb passages. Maybe the idle passages are blocked or even the primary necessitating the extra throttle?

 

[Pighead]

It doesn't take a very big piece of crud to block some carb passages.

Indeed, I thought I had caught one after the first RR (Redneck Rebuild) and the float bowl filled and would not empty. I figured something was stuck in the needle valve. The second RR seemed to clear it as fuel level returned to normal. But the rig runs and idles normally on flat ground. Can tolerate mild downhills, just tries to die on a steep downhill.

 

[Pighead]

Took it apart, lowered the fuel level just a hair, drove it around a bit. Runs during the downhills nearby. Probably good enough to get me up Cadillac. This carbs gonna get a thorough going through when it gets home. Gotta change out that fawking rubber-tipped needle..