2150 and Fuel/air mix not right. Cant get jetting right

[rusty ol ranger]

View attachment 47655View attachment 47656

This is after running hard down the street and shutting off and pulling into a safe place. This is with cruising and hard driving (power valve) 10 degrees of timing.

You need to run it further then down the street.

 

[MadMax_636]

You need to run it further then down the street.

I ran it down the full length of the road. I just drove 45 miles an hour which is the speed limit.

 

[rusty ol ranger]

I ran it down the full length of the road. I just drove 45 miles an hour which is the speed limit.

I dont even attempt to read plugs untill ive put atleast 30 miles on it.

What i would do is set your idle screws (speed and mix) back to base and go from there.

However, im still really betting on a blown intake gasket on that cylinder.

 

[MadMax_636]

I dont even attempt to read plugs untill ive put atleast 30 miles on it.

What i would do is set your idle screws (speed and mix) back to base and go from there.

However, im still really betting on a blown intake gasket on that cylinder.

I sure do hope that its not a blown intake gasket. The pictures aren't the same cylinder. Its 1 plug from each side.

 

[rusty ol ranger]

I sure do hope that its not a blown intake gasket. The pictures aren't the same cylinder. Its 1 plug from each side.

One plug on each side? I thought it was just one plug? Wtf?

Are they across from each other?

 

[MadMax_636]

One plug on each side? I thought it was just one plug? Wtf?

Are they across from each other?

Yeah, Not sure if this is because they are new plugs but yeah. This is also with 56 sized carb jets.

 

[rusty ol ranger]

Yeah, Not sure if this is because they are new plugs but yeah. This is also with 56 sized carb jets.

You replaced all 6 plugs? Or only the two? Either way theres no way a plug problem could cause this. Theres also no way a jetting/carb problem would cause this.

The carb feeds all the cylinders, so if its lean enough to leave one plug clean its lean enough to leave them all clean.

The ONLY way i could see ignition playing into this is if youre not getting good spark on the other 4/5 cylinders but then itd run like shit.

 

[rusty ol ranger]

Mouse or somethin didnt make a nest in an intake port did it? Some other blockage?

 

[MadMax_636]

You replaced all 6 plugs? Or only the two? Either way theres no way a plug problem could cause this. Theres also no way a jetting/carb problem would cause this.

The carb feeds all the cylinders, so if its lean enough to leave one plug clean its lean enough to leave them all clean.

The ONLY way i could see ignition playing into this is if youre not getting good spark on the other 4/5 cylinders but then itd run like shit.

I replaced all 6. I dont have any idle stumble. I have a nice steady 19 - 20 inches of vacuum at idle at 10 degrees. I did set the gap to .040 since out of the box. It was 0.36-38. It was small. When I set it to .044 it ran poopy. Im thinking my coil might be the issue but idk.

 

[MadMax_636]

Mouse or somethin didnt make a nest in an intake port did it? Some other blockage?

Na, This truck is driven daily so a stuirt little wouldnt have enough time. Plus, Since its daily driven. Its also daily fucked with. Im also tuning something. Either the choke, idle speed, or trying to adjust the return spring.

 

[RonD]

You need a Choke on a cold gasoline engine, so get a manual choke cable in the cab

Good read here on 2150 and 2.8l: https://www.therangerstation.com/fo...s/1984-ranger-2-8-motorcraft-2150-jets.98716/

The 'idler' screws ARE the AFR adjustment, they are always feeding fuel into the engine, at idle and wide open throttle(WOT), so you can Richen one bank by turning that sides screw out a bit, but this would mean you have an air leak or other issue on that bank

You need a week or so to get any readable color on spark plugs tips unless you are getting oil in the cylinder, then you know right away, lol

A vacuum gauge is a very good tool to have and to use on any gasoline engine(carb or EFI) for many tests and tuning

 

[rusty ol ranger]

I replaced all 6. I dont have any idle stumble. I have a nice steady 19 - 20 inches of vacuum at idle at 10 degrees. I did set the gap to .040 since out of the box. It was 0.36-38. It was small. When I set it to .044 it ran poopy. Im thinking my coil might be the issue but idk.

Coil still fires all 6 cylinders and with a weak spark youd have black plugs.

With the motor running and a fire extinguisher handy get some starting fluid and spray on the offending cylinders intake port where the manifold meets the head and see if the idje speeds up, if it does its an intake gasket.

But with it running good and all that vaccuum if its not the gasket im out of ideas.

 

[rusty ol ranger]

You need a Choke on a cold gasoline engine, so get a manual choke cable in the cab

Good read here on 2150 and 2.8l: https://www.therangerstation.com/fo...s/1984-ranger-2-8-motorcraft-2150-jets.98716/

The 'idler' screws ARE the AFR adjustment, they are always feeding fuel into the engine, so you can Richen one side by turn that sides screw out a bit

You need a week or so to get readable color on spark plugs tips unless you are getting oil in the cylinder, then you know right away, lol

A vacuum gauge is a very good tool to have and to use on any gasoline engine(carb or EFI) for many test and tuning

If it waa a carb problem all the cylinders, or atleast those on the same bank, would all be the same

 

[RonD]

Yes, +1 if.............all things are equal

 

[rusty ol ranger]

Yes, +1 if.............all things are equal

Thats why im thinking hes got vacuum loss to that one cylinder....through a bad intake gasket

If it was rings id think the plug would be oil fouled. Only other remote option would be a burned exhaust valve.