Tips for Carbs in Cold Elevation - Don’t want EFI

[cldonley]

Third picture top view of carb, left side of carb, the round hole with brass plug above the oval fitting is the port. Bruce punches out the plug, threads it, and inside that is the screw, easy prays. I’d just buy one from him though buying from that site and experimenting, that and they want over $700 with core charge, that’s about what I paid Bruce, but that was about 10 years ago, it seems.

Do you have contact info for him? I found a guy in Ohio who specializes in Qjets but didn't see anything on his site about the altitude compensating model.

 

[Soylent]

Do you have contact info for him? I found a guy in Ohio who specializes in Qjets but didn't see anything on his site about the altitude compensating model.

This is him. Rebuilt my Qjet. A great guy.

https://www.google.com/search?clien...QIHBAD&biw=430&bih=873&dpr=3#lpg=cid:CgIgAQ==

 

[73azbronco]

rebuilt my qjet as well, as well as a couple well known (i have no clue who they are) award winning rock crawlers.

 

[BOBS 2 68S]

I am running a Holley Track Avenger 570cfm on my 302. When it sits for a week or so I do have to crank it to get fuel to it. I live at 5000ft and wheel all over Colorado, I don't change jets or any thing when I am wheeling. As far as cold weather, 1/2 dozen pumps and it will start. I don't use the choke until the I get oil pressure. The other morning when it was -16 degrees it started with no problem. Holley in not my 1st choice. But it's not broken so it's not going to get fixed. Have been looking at the qjets, they are not in my retired budget any more. I need to get my other Bronco back on the road.
So just saying a carb will start when it cold.

 

[.94 OR]

I used to run the Motorcraft 4100 carb when I lived in Idaho. Open paper filter caused the issue since I didn't have any preheat to the carb.
I lived about 5 miles out of town and by the time I hit the city limits I could tell it was iced up. Coast into the Mormon church parking lot, turn the key off and pull the manual choke all the way out and read a magazine for about 4-5 minutes. Push the choke in, fire it up and continue for the rest of the day.
Had to have the engine heat filter up through the carb to thaw it out for those couple few minutes to de-ice it. Never did put preheat to it.
On the flip side, I had a Stihl 044 that I used for thinning in the winter and I had to do the same trick on it. Sucked balls while standing in sub-freezing temps waiting for the saw to thaw out before I could start working so I could keep warm.

 

[m_m70]

So just saying a carb will start when it cold.

Yup! They were the only option for a lot of years. Not like all the cars stopped running in the cold

 

[BOBS 2 68S]

So back in the day 1995 ish I hunted the November elk season here in CO. And yes the carb did ice up but a bottle of "Heet fuel additive" stopped the icing problem. I kept 4 bottles in the war bag just for that week of hunting. And speaking of cold more than once it was -28 degrees up there, the Bronco would start with a few pumps of gas.

 

[wjochem]

Sounds like progress!

In addition to adjusting your metering and idle screws at elevation, don't forget to adjust your timing by about 1 deg per 1000 ft elevation. Having lived at Denver, Colorado elevation, 5280, and going up to timberline around 10k and above with a carbureted bronco, jeep etc I can tell you that while the carb adjustments do help, adjusting your timing can help just as much. Since you have a manual choke you don't have to worry about properly adjusting an electric choke. The only other thing that some run into in extremely cold temps is carburetor icing so a properly working 'hot air' system or other carb warming system can be beneficial. On the old carbureted air cleaners they had a tube that would run from the exhaust manifold to the air cleaner. During cold weather a flap in the air cleaner snorkel would close so that intake air was drawn through the tube and get warm air as the exhaust manifold would warm up. Some engines like the ford inline 200 had a carb spacer that the heater hose would hook up to and would use engine coolant to keep the carb from icing up.

Back before fuel injection people coming from lower elevations and driving I-70 up and through the Eisenhower Tunnels would blow back smoke as the carburetor was set up way too rich for that altitude and would foul spark plugs. I'd also run a good 10-40 oil as 20-50 is very heavy.