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vlagtempest
05-07-2013, 06:26 AM
can anyone give me or direct me to a photo of where the mixture screws are. on the original mikuni carbs that came with the 1986 dodge ram 50 2.0l. I have tried the two screws that the other sites talk about but only one of them changes any reaction on the motor and I'm getting a lot of drag when gas pedal is half to 3/4 down.

77amc
05-07-2013, 07:34 AM
can anyone give me or direct me to a photo of where the mixture screws are. on the original mikuni carbs that came with the 1986 dodge ram 50 2.0l. I have tried the two screws that the other sites talk about but only one of them changes any reaction on the motor and I'm getting a lot of drag when gas pedal is half to 3/4 down.

DRAG? Black smoke or back-firing and bucking with no go..?
Could be float if someone has been in it before, or black being too rich.

On the 'other sites' what do 'they' say those screws are for?
I got a 2.6 carb but I don't know if they would be the same.

Going out on a limb here but check the timing FIRST. If it's off or advance bad it could make one think it's another thing.

E

vlagtempest
05-07-2013, 08:02 AM
DRAG? Black smoke or back-firing and bucking with no go..?
Could be float if someone has been in it before, or black being too rich.

On the 'other sites' what do 'they' say those screws are for?
I got a 2.6 carb but I don't know if they would be the same.

Going out on a limb here but check the timing FIRST. If it's off or advance bad it could make one think it's another thing.

E

if its the same year the 2.6 and the 2.0 stock carbs are the same as long as it is a 2 barrel i found that out atleast. the other sites are saying that the screws are right next to the throttle cable. and what i mean by drag is that it bogs it backfires but only when the motor is cold after warm up a lot of the bogging goes away. I have big plans for this truck but only if i can get it running right. Timing is set. I set it myselft then thought the same as you and had someone else check it to make sure. It blows white smoke when first starting then goes away.

Acuta73
05-07-2013, 09:35 AM
Was pretty sure the mixture on the Mikuni is plugged. Could be wrong, but I know there are screws that are plugged...and pretty damn sure that's what they are.

If someone rebuilt it, it probably doesn't have plugs anymore.

BradMph
05-07-2013, 10:11 AM
Your right Acuta73, they are plugged from factory. Your able to chip the material out and make adjustments if needed. I'm pretty sure it was incased for smog reasons and kept mitsubishi from having to service an overdose of curious screwdrivers. The screw or sealed area was on the drivers side and face left if sitting it the drivers seat. Kind of close to the EGR sub valve.

77amc
05-08-2013, 04:02 AM
OK, next I would take a can of carb cleaner (and Jet nozzle) after its' warm and shoot 'short' bursts around your vacuum lines (all 20' of them) and carb base. does it change idle?
If so, it could be broken/split vacumm lines. OR lines that are in the wrong place if it's been 'worked on'..

What's it idling at now? (when this all started) Above 800 or below?
Usually a backfire along with a bog, 'tickling' the throttle to have the acc/pump feed it, is too lean and a bog-while climbing up to high rpms is rich (along with some fuel spittin or noticable vapor coming up from the air-horn) That's why some think that they have the right carb (TOO BIG) because they OR the buddy that sold it to them, get it up to around 3000 and spike it to 4500-5500 or so with a big grin on their face.. DANG DUDE!! That's SWEET!
Well, at those rpms, yeah--there's tons of air getting mixed with the fuel!! But it runs like poop, fouling plugs around town under 2500 with a smell of gas that 'chicky-doo' doesn't like and KEEPS reminding YOU of it..
Is the accelerator pump squirting into the throat (under the butter-fly)? OR just piddling it in? (STAY FOCUSED.. Getchur mind outta tha gutter)

WHITE "SMOKE" or steam of condensation of heating the pipes?
Steam usually disapates within several inches to a foot or so, whereas SMOKE lingers up to 8-10' or more with a lovely smell of coolant.


Sorry, I'be up since 330 or so..

E

mclarry01
07-30-2015, 02:27 PM
I had the same problem and came to find out that my distributor timing was off by two notches. redo the timing from the crank pulley and make sure its on the "T" and NOT TDC "A" or TDC "B" after which there will be a moulded thin line on your distributor cap. if your rotor has three prongs on it, line up the middle prong with the moulded line and meticulously maneuver the distributor such that once the cogs engage with the cam pulley cogs, the middle prong on rotor is aligned with the thin mould line. I had to use a mini hacksaw to create a notch on the metallic housing of the shaft just so that I had better alignment. will post a pic shortly once I get home