Ok trying to get my truck back on the road. The initial problem was a hesitation and than the engine falling flat and dying. It was club members daily driver 81,000 352. Thought it could be a coil, replaced that...still there, rebuilt the carb, new plugs and wires....runs better. I have spark, getting fuel, set the timing, adjusted the carb. The issue is at start up the truck runs really rough, will die if not feathered, but gets better once it warms up....but still seems to have a slight miss. It has an accel module in the stock distributor. The only thing I can think of is a bad va*** advance? I pulled the line and tried the old inhale and hold the tongue, couldn't really tell from that. Wouldn't that cause the engine to run like **** until it warms up? Getting frustrated with this one...but I gotta think it's ignition related?
Thinking again - sounds like a choke issue, if it gets better when hot Singlefingerspeedshop.com. Detroit
Mech pump and manual choke. Pump has plenty of pressure, tanks clean, new filter in pump and new in line filter... So no issues with fuel delivery at all
If it's not a choke problem, a vacuum leak would be the next logical thing. As it warms up, things grow and swell gradually closing the leak partially. Pretty decent guess.
Well I got 1 va*** line and that going from the distributor va*** advance to the carb. Pcv is good..gonna buy a va*** gauge and pump today. Don't know where else I could have va*** leaks.
Intake manifold to heads, carb to intake, throttle shafts at carb ... Best way to check is to spray it down with carb cleaner while its running and listen for a change in how its running. Might be tricky on a 352. If its leaking it will **** the carb cleaner and change your air fuel mixture. PCV valve thats operating and set up correctly is a controlled vacuum leak, if its not proper it's not controlled and just a vacuum leak.
You said in your post it has a 352. That may make it a mid to late 60's Ford. They often had an aluminum spacer under the carb for a vacuum source for brakes. They would rot out on the bottom rear, almost impossible to see. Remove whatever is there and check it.
Take off your air cleaner with the motor running. Place your hand over the air horn, if the idle picks up and smooths out, you have a vacuum leak. A simple and accurate 20 second check.
Aren't hands great multi purpose testers? You can use them to test for a vacuum leak, make great chokes to get a car started, work really good to check for spark , best tool for checking for a clogged radiator and I'm sure there are many more.
No power brakes on this one. I know the spacer your talking about, it looked ok when I put the carb on it.
Ok did that and yep smoothed out...now to find the damn va*** leak! One thing odd is the new pcv valve I put in rattles like a mofo....oreilys said it was right...it looked like a cheapo...uhhhh this thing is driving me nuts
Plug your PCV valve first, just pop it out and place a finger over it and see what it does. Post #9 shows what to do with carb cleaner which always works. Look at all your vacuum hoses, make sure the carb is not loose.
Did you use the proper gasket for the plate under the carb they are not the same as the one under the carb. The gasket between the plate and intake is different between the plate and carb.
If I recall correctly those old 352 intake manifold gaskets would **** in and cause vacuum leaks. Bad thing was you had to pull the rocker covers to check it out. After you got the covers off, you could start it up & spray carb cleaner where the intake manifold would meet the cyl. head. As mentioned, if the idle picked up you've found your leak.
Ok so I had the carb off for rebuild....I'll check that...of course I just put my cal custom valve covers on to replace the leaking stockers. I plugged the va*** port for the pcv and it still ran with no issues.
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