Loss of power under load

[ngsd]

From experience, I have a 78 block someone must have swapped the cam, with the old firing order it started and idled, I had some backfire revving it up no load, and no power under load. Swapped 4 wires after 7 days of troubleshooting and its really a nice running engine.

Its similar issues to what you are saying, and with all the work you have done, you said you swapped dist. over? I'd look at plug wires and timing.

Thanks, I have the old distributor on the shelf, that may give a clue if the wires are reversed on it. I will take a look at that tonight. If it were that far off, would it still start easily, idle and rev smoothly?

 

[ngsd]

Did it ever backfire or "sneeze" through the carb when you were first trying to start it?

No it did not, it did though after it stalled out upon acceleration.

 

[Broncobowsher]

Fuel pickup, fuel filter...

I would be looking at putting a fuel pressure gauge on it and see what happens under load.

It could be the new engine actually runs good enough now to need more fuel than the old engine needed. The old setup was acceptable for a weak engine but not good enough for a good engine.

 

[ngsd]

Fuel pickup, fuel filter...

I would be looking at putting a fuel pressure gauge on it and see what happens under load.

It could be the new engine actually runs good enough now to need more fuel than the old engine needed. The old setup was acceptable for a weak engine but not good enough for a good engine.

Yes I am leaning this way and all good suggestions. Tonight I will check the wires first and then check fuel flow. They were both older worn engines so probably pretty comparable there but it sure does feel like it is starving for fuel.

 

[Rustytruck]

my guess low float level.

 

[ngsd]

So i swapped the wires and that was not the issue. I advanced the timming by 22 degrees and it now solved that issue. The distributor position looks out of whack but I cant get it in any other way. Timing gear off a tooth?

 

[Madgyver]

had similar symptoms when the OEM timing gear tooth fell apart.

 

[Broncobowsher]

So i swapped the wires and that was not the issue. I advanced the timming by 22 degrees and it now solved that issue. The distributor position looks out of whack but I cant get it in any other way. Timing gear off a tooth?

Very likely. I've dropped them in a tooth off and thought I could just twist it enough to make it work. I always end up pulling it out, jump a tooth, put it together correctly.

 

[blubuckaroo]

The distributor position looks out of whack but I cant get it in any other way. Timing gear off a tooth?

I've seen owners struggle when reinstalling the distributor. It usually won't go all the way in because it's not lining up with the oil pump hex drive.
Don't sweat getting the hex drive to line up. Just put the distributor in where you want it. It will be sitting a bit high. have someone press down on it while you bump the starter. It'll fall right into place.

 

[ngsd]

Thanks for all of the help. The last post about installing the distributor did the trick. I really struggled with that but it finally runs good now. I also went ahead and rebuilt the original carb and took the Chinese junk off there so at least it pushed me to do that. Now I have to figure out why my new rear main seal is leaking! I hate those things, i had the engine out and installed a new 2 piece seal and thought I had it done right but I guess I messed that one up. I just did one in my other engine and it worked perfectly. ugh always something else to do....

 

[jckkys]

I never miss a chance to point out that sellers who say they have new 2150s, don't. They are really just Chinese garbage. A real 2150 has Motorcraft cast on the top cover, and there are no new ones. There are plenty of used 2100s and 2150s that just need a rebuild. The best ones are the originals that Ford calibrated for your engine.

 

[blubuckaroo]

Once I knuckled under, and bought a rebuilt 2150 from a reputable auto part store. It just didn't look right. Turned out it was missing the whole venturi booster assembly.
I went back and asked for my core back. They said it was gone. I dug through their crap till I found it.
After a rebuild, it was fine.

 

[ngsd]

I also was wondering if the 1" aluminum spacer under the carb is stock or aftermarket, I cant remember not seeing one as both of mine had them.