truck running with sluggish mid range rpm

[pryorfire48]

I got my m37 running the other day after having trouble getting it started. Took it for a drive some city and some highway. I have to feather the throttle on take off and she sounds great on high rpm. When traveling down the highway it's a dog but as the rpm and speed increase you can feel the power return. Any ideas what to look at or adjust?

[Master Yota]

There are far better carb guru's than me on here, but the "feathering the throttle" part sounds alot like an accelerator pump issue...

[hbb]

From what you are stating there could be several things going on, you will probably need too remove the carb and clean the varnished fuel out of the fuel passages and the pilot jet. When it is apart you will be able to check float levels and make the proper adjustments and inspect the accelerator piston repair as needed, the varnished fuel is most likely the culprit these carbs are fairly simple but demand clean fuel.Check the fuel filter for crud and basic inspections of the fuel system.most of the overhaul kits that are available come complete with accelerator piston and gaskets(they do not come with a float)and many of the brass component's.Midwest is where I gotten my carb kits from.


hb

[cuz]

You are describing an engine that is difficult to start, slow to accelerate yet runs well once up on speed and in the higher RPM ranges.

Before you start pulling stuff off make a few simple checks.

Open the distributor cap and check to see if the centrifugal advance is free to rotate and spring back. Or connect a timing light and verify the timing advances when you punch the accelerator. Check point gap.

If the timing automatic advance works and when you punch the throttle you get a very slow increase in RPM then look at the carb.

Has this problem jumped out of no where or have you made any changes or adjustments to the engine/ignition/fuel system lately?

[hbb]

Wes is totally correct in his statements about not pulling the trigger on the carb with out checking the the obvious on the electrical, timing ,points and condenser,distributer condition and just a good inspection. I will ask the same question again did this problem just start up from nowhere.

These vehicles are so simple but so can-cankerous with shield ignition and the intake air horn that you cant see down the throat of the carb to see if there is fuel or not and how much.

What i am concurring is to do the basic checks before diving in half cocked and doing somthing that is not needed.

hb

[anthony manzella]

Mine was sum what the same way all it took was a timing light and a good old fashion adjustment on the carb now you can tell the differance . .

[pryorfire48]

i had replaced the head gasket then had trouble getting the truck to start. I replaced the points and condenser and finally go her to run. She runs better at least she hits on all 6 cylinders now, but i had to feather the throttle before all the work.

I tried advancing the distributor when i got home and she perks right up. So right now i need to make sure that the timing is right and the distributor is tightened down.

I had made all of the checks to the timing advance when i pulled the distributor out. Everything is getting put back together right, vent lines connections and such, so i expect to make a few adjustments.

[peter e mark]

Sounds like a problem I had with my 52, but it turned out to be a clogged fuel line. Installed a new line from the tank all the way up to the fuel pump, and no more of that!...