Vacuum leak?
Thread Starter
|
Senior User
Joined: Dec 2014
Posts: 233
Likes: 0
From: Buffalo
Vacuum leak?
Got an odd one here (or maybe not so odd.) My '84 seems to idle just fine (although it is running a bit rich). I have what seems to be decent acceleration through 1st gear and somewhat decent through second gear. Third sucks. Now, I notice that if I accelerate normally while in second gear I get this strange hissing noise that will go away completely if I let up on the accelerator. If I accelerate lightly in second the hissing is non-existent. Anyone know what this might be.
My first thought is vacuum leak but it would have to be something major like an intake manifold gasket (maybe?) Carb gasket should be fine as I just rebuilt the carb and put new gaskets on.
Also, are these factory 2bbl's adjustable in the sense of air/fuel mixture so I can lean it out a little? The exhaust makes me cry (literally, lol)
My first thought is vacuum leak but it would have to be something major like an intake manifold gasket (maybe?) Carb gasket should be fine as I just rebuilt the carb and put new gaskets on.
Also, are these factory 2bbl's adjustable in the sense of air/fuel mixture so I can lean it out a little? The exhaust makes me cry (literally, lol)
Thread Starter
|
Senior User
Joined: Dec 2014
Posts: 233
Likes: 0
From: Buffalo
There is not a catalytic converter on this truck. Canada built, no computer if that means anything? No clue, but no cat.
Moderator
Joined: Jan 2001
Posts: 56,973
Likes: 2,731
From: Virginia
Vacuum leaks affect the idle more than anything. A large vacuum leak will not let the engine idle hardly at all. A small vacuum leak will be so small compared to all the air going in the carb at high speed, it does not affect higher rpm operation.
How's your timing?
How's your timing?
Thread Starter
|
Senior User
Joined: Dec 2014
Posts: 233
Likes: 0
From: Buffalo
Have not checked timing yet. That will be next. Something is causing a "hissing" noise while accelerating. Only seems to do it in second gear. Strange.
Thread Starter
|
Senior User
Joined: Dec 2014
Posts: 233
Likes: 0
From: Buffalo
well, 42K on odometer, but there's a slight chance it's 142K. Tough to tell. Truck is nearly mint but interior was destroyed (could just be Florida sun for 31 years). I wanna say it's a true 42K but too hard to tell.
Trending Topics
Moderator
Joined: Jan 2001
Posts: 56,973
Likes: 2,731
From: Virginia
If you are going to put a timing light on it anyway, loosen the bolt on the dist just a little bit, start the engine and then twist the dist just a little bit till the engine speeds up. Turn the engine off, lock the bolt back down and take it for a test drive, see if it improves.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Thread
Thread Starter
Forum
Replies
Last Post
SEB72
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
3
Feb 21, 2014 06:21 PM