170 Lag on Throttle

63RancheroGuy

Active member
Hi guys,

This is my first post.

I've got a new (to me) '63 Ranchero with the 170ci and 4-speed manual. Engine was rebuilt about 500 miles ago, but those 500 miles took about 15 years to put on - so it hasn't been driven a lot and gas has been sitting in it for a while.

I got the idle and timing set (for now). Idles good after she's warmed up. BUT here's the problem, when I step on the gas more than just a little it lags, almost dies, sputters, until I let up on the accelerator.

My first thought: Accelerator Pump Diaphragm! I didn't see any gas squirting in when I press down the accelerator or pull the linkage. So I changed it out, and according to some of your suggestions in the forum I took a flat file to the "housing" because it had warped - quite a bit. Put it back together, got a nice good seal, no gas leaking. BUT! Still no gas squirting - still the same acceleration lag.

I'm thinking one of the accelerator pump jets could be plugged?

Should I be able to see gas squirting when I press the accelerator down?

If one of the accel pump jets is plugged, how do you check that, and how do you fix that?

I did a quick check for vaccuum leaks (starting fluid test) but didn't find any. Is there a better way to test?

Any suggestions greatly appreciated.

Adam
 
Hi, I should've mentioned that huh?

It's got the Ford 1100 carburetor with just one accelerator pump (manual transmission).

Adam
 
63RancheroGuy":38q83avd said:
...
I'm thinking one of the accelerator pump jets could be plugged?

Should I be able to see gas squirting when I press the accelerator down?

If one of the accel pump jets is plugged, how do you check that, and how do you fix that?

I did a quick check for vaccuum leaks (starting fluid test) but didn't find any. Is there a better way to test?
...
* Yes, although it's not so much a jet as a couple of passages from the pump to the throttle bore.
* Yes.
* The only way to check the accel passages is to take the carb apart (easy with an 1100) and blow/spray some cleaner through the passages, making sure they're clear.
* The starting fluid test is as good a way as any to find vacuum leaks. What is your vacuum reading at warm idle, and is it steady?

Something else to look for in the Accel Pump is the checkballs. IIRC, there are two, one each at the inlet and outlet. Or they may be rectangular check "balls", I forget.

I think you're on the right track with the Accel Pump.
 
Thanks Jamyers,

I don't have a vac gauge. Probably need to invest in one.

What should I check the "check-balls" for? Corrosion? Are they serviceable?

Looks like I'll be doing a carb rebuild - I bought a full kit when I replaced the accel pump diaphragm.

Any tips or tricks on that business appreciated.

Adam
 
I accidentally lost the check ball the last time I had my 1100 apart to clean and adjust the float, had the same problem. The check balls come with the kit as does a new needle valve and seat,pump diaphragm. I cleaned mine up with carb cleaner and compressed air, freed up a sticky power valve and set the float level as high as possible(full carb seems to help the fuel boil issue in hot weather), I also went to a manual choke and removed the choke heat tube. These are wonderfully simple carbs to work on (if I can do it anyone can) :rolflmao: Good luck!
 
Thanks sixpony,

Haven't experienced the fuel-boil issue yet - only had the car a month or so. Not exactly hot weather in the pacific northwest this time of year.

Is the power valve the same as the "Spark Control Valve" A new one came with my kit and it was an easy change out so I changed that out while I was putting on the new accel pump diaphragm.

Mine has the original manual choke. What year is yours?

Not a mechanical genius here, enough confidence to be dangerous, so any help on getting the floats adjusted would be appreciated.

Guys - do you think I should take the whole carb apart or can I just pop open the carb and clean out and service those checkballs without a full break down and rebuild?

Thanks again,

Adam
 
Update:

I took the carb off and tried to spray carb cleaner through the "passage" or "circuit" or whatever you call it from the accelerator pump into the intake. Nothing would go through, it just blew back. Took the lid off the carb, tried to spray through each different section. Found the clog. Sprayed the carb cleaner backwards through the outlet, after a second it blew out the other side. Got it cleaned out both ways. Sprayed the cleaner through everything else while I had it apart. Blew everything clean with the air compressor.

While I had it apart I changed out the check balls, too. I don't know if I needed to but I figured while I'm at it.

Put it back together, and other than having to clean up a little bit of "slop" in the accelerator pump linkage (which I did), it works 100% better. Clean acceleration, no lag.

Thanks for the help guys!

Adam
 
Congratulations!

It's always cool to look into a problem, find and fix the problem.

I noticed you mentioned you are in the Pacific NW. Glad to hear someone else on the forum is in this area.

Have fun, Ric.
 
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