losing power at high altitudes

[tkelley80905]

Hello everyone, I own a 1984 bronco ii with a 2.8, it has a carb.I have been takin git up into the mtns here lately and it seems to lose power on my way up, i dont seem to be able to get it to go fast enough to get out of second gear.This is in two wheel, when i put it in 4 lo it does better.It seems once i get up there it does ok, especially on the way back down it runs fine.Is there anything i can do to make it run better up there? I was thinking about adding an in line electric fuel pump,or does anyone have an better sugestions?

 

[kimcrwbr1]

I suppose you could change jets in the carb to account for altitude but it will run rich at lower elevations. Are you running with the computer maybe doing the duraspark and eliminating the feedback carb would help also.

 

[tkelley80905]

When you ask am i running with the computer what exactly do you mean? I know the pump is unhooked,( no belt) and most of the smog pump stuff is gone cut off or missing.There where some things missing from the engine that had to do with the emmisions and the piece on the carb that idles the engine up when the ac comes on,that has been taken off,but im not sure what computer your talking about?

 

[kimcrwbr1]

Just thinking if you have the feedback carb maybe you could get a used feedback solenoid from the bone yard and unplug the one on the carb plug the other one in so the computer thinks it is still there to make the carb run rich. That is the rectangular electrical connector on the back of the carb

 

[kimcrwbr1]

Does the distributor have the long 6 wire connector on it

 

[tkelley80905]

Oh ok yes it is still plugged in , it was unplugged at one time. i may give that a shot and see what that does.

 

[kimcrwbr1]

Either It has been durasparked or it is running in limp mode meaning the distributor is not advancing properly I imagine the gas mileage sucks too

 

[kimcrwbr1]

It will cost about $130 for the distributor cap rotor and module you can use the same coil and carb just put a metering block where the feedback valve is. It will bring your engine to life do you need to pass emissions

 

[kimcrwbr1]

In the tech library It tells you what you need for parts and how to hook it up look under duraspark conversion

 

[tkelley80905]

it hasnt been durasparked, i would like to do that but i dont trust myself to get it timed right. i have messed with the ditributor and ill bet i have it down to low.i turned it so it would idle down because it had a small back fire as it was idleing, i have messed with the air and fuel mixture screws on the carb also. i think i should have left it alone now.

 

[kimcrwbr1]

I also put new valve guide seals in I imagine your engine uses oil too It is highly recommended to do that also mine only had two seals that were still kinna there but hard as a rock. All you need is a compressor and plug adaptor and a spring compressor it took me about three hrs.

 

[kimcrwbr1]

If you messed with the timing without a light chances are your not close enough. It needs to be at 10 degrees BTDC. For the idle turn both of them out two turns from lightly seated and one at a time turn them in till it runs rough then back out for the highest idle do that a couple of times till you get the highest idle then turn them both in 1/4 turn at a time till it starts to drop then back out 1/4. once you get it set you can check it by counting the turns in then back out and they should not be mor than 1/2 a turn between them

 

[kimcrwbr1]

Oh yea when you messed with the timing did you disconnect the spout wire at the same time if not then you are more than likely way off.

 

[tkelley80905]

When i started to have problems with this bronco ii i got another carb from the junk yard.It ran and still does better then with the old carb.I changed the oil in it months ago and it is still full, it doesnt burn oil or leak any oil. The spark plugs have normal wear on them, the antifreeze is never that low.It doesnt smoke and it runs great here in town, it will do 80 85 on the high way. Its just recently i have made a few trips up into the mtns and i noticed a very big decline in power while im going up.it seems once im up there we make a stop at an oulook, when i start it back up from there and go on it runs pretty normal.I just read the dura spark conversion and i may try that with my sons help one day.

 

[tkelley80905]

No i sure didnt unplug that wire.

Oh yea when you messed with the timing did you disconnect the spout wire at the same time if not then you are more than likely way off.