Serious Hesitation Almost Stall
Thread Starter
3rd Gear
Joined: Nov 2008
Posts: 3
Likes: 0
Serious Hesitation Almost Stall
Hi,
I'm new to the forum. I actually joined to try and help my dad figure out what's wrong with his 74. It has a seriou hestitation (almost to the point of stalling) when you get on the gas. You end up having to pump the pedal to get it going without stalling. Once you hit the higher RPM it seems to run fine.
While driving, we smelled burning oil as well. So we got udner the car and saw that there was oil EVERYWHERE. It looks like the oil was burning off where the header meets the downpipe. Looking through the engine bay, the oil seems to be from the valve cover down.
So, my first though is that the valve cover gaskets needs repalcement (has never been replaced), but that wouldn't cause the hestitation. Maybe they are two seperate issue?
Any thoughts or suggestions on what the issue could be and potential solutions could be would be greatly appreciated.
Thanks in advance for the help!!!
I'm new to the forum. I actually joined to try and help my dad figure out what's wrong with his 74. It has a seriou hestitation (almost to the point of stalling) when you get on the gas. You end up having to pump the pedal to get it going without stalling. Once you hit the higher RPM it seems to run fine.
While driving, we smelled burning oil as well. So we got udner the car and saw that there was oil EVERYWHERE. It looks like the oil was burning off where the header meets the downpipe. Looking through the engine bay, the oil seems to be from the valve cover down.
So, my first though is that the valve cover gaskets needs repalcement (has never been replaced), but that wouldn't cause the hestitation. Maybe they are two seperate issue?
Any thoughts or suggestions on what the issue could be and potential solutions could be would be greatly appreciated.
Thanks in advance for the help!!!
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 493
From: Salmon Arm, BC
Welcome!!
The first thing I would do is remove the aircleaner and look down into the carb. While doing this move the linkage to wide open throttle (All done with the engine off). What your looking for is a nice consistant squirt of fuel from the accelerator pump squirters, which are in the primary bores (the small ones). Check this out and report back.
The first thing I would do is remove the aircleaner and look down into the carb. While doing this move the linkage to wide open throttle (All done with the engine off). What your looking for is a nice consistant squirt of fuel from the accelerator pump squirters, which are in the primary bores (the small ones). Check this out and report back.
Pro
Joined: Jul 2008
Posts: 660
Likes: 1
From: Springfield Tennessee
St. Jude Donor '09
I'm thinking you've got a piece of trash in the bowl. When you 'get on it' it picks up and gets in the needle seat. When you pump the peddle it flushes back into the bowl and lets the engine catch back up causing a steadier flow allowing the trash to settle back to the bottom until that 'gettin on it' again.
And I'm guessing that when you say 'get on it' you're already cruising down the road and you punch it.
And I'm guessing that when you say 'get on it' you're already cruising down the road and you punch it.
Last edited by Dream Ride; Nov 22, 2008 at 09:41 PM.
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Welcome!!
The first thing I would do is remove the aircleaner and look down into the carb. While doing this move the linkage to wide open throttle (All done with the engine off). What your looking for is a nice consistant squirt of fuel from the accelerator pump squirters, which are in the primary bores (the small ones). Check this out and report back.
The first thing I would do is remove the aircleaner and look down into the carb. While doing this move the linkage to wide open throttle (All done with the engine off). What your looking for is a nice consistant squirt of fuel from the accelerator pump squirters, which are in the primary bores (the small ones). Check this out and report back.
...
Thread Starter
3rd Gear
Joined: Nov 2008
Posts: 3
Likes: 0
Welcome!!
The first thing I would do is remove the aircleaner and look down into the carb. While doing this move the linkage to wide open throttle (All done with the engine off). What your looking for is a nice consistant squirt of fuel from the accelerator pump squirters, which are in the primary bores (the small ones). Check this out and report back.
The first thing I would do is remove the aircleaner and look down into the carb. While doing this move the linkage to wide open throttle (All done with the engine off). What your looking for is a nice consistant squirt of fuel from the accelerator pump squirters, which are in the primary bores (the small ones). Check this out and report back.
First, thanks for alll the responses, I really appreciate it.
So, i took a look and it seems that i am getting a decent 'squirt' when pulling the throttle linkage to WOT. It probably could be a little stronger (as the carbs have never been cleaned), but I think it's a strong enough stream to get her going.
Dream Ride,
I took a look down into primaries and secondaries and didn't see anything. Actually for a 35 year old carb (that has never been clearned), looked pretty clean. Is visual inspection enough to verify this?
Avette,
I'm going to take a look at the timing now. I read Barryk's write up (which had alot of great information). Based on that write up, I'm going to set the initial with the a rubber band around the centrifugal springs then take it off and see if the timing changes. If it does, it points to the centrigifual springs, right?
Will let you know how the timing goes! Thanks againg guys for the help.
Last edited by R Vette; Nov 23, 2008 at 11:12 AM.
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 493
From: Salmon Arm, BC
Check the timing and report back. If everything is original you might consider spending a few bucks and rebuild a few of the more critical items (carb,Ignition). But first lets find out whats causing your problem......What do your plugs look like? check all eight.
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Thread Starter
3rd Gear
Joined: Nov 2008
Posts: 3
Likes: 0
So we checked the timing. It was at like 12-14 degrees, so we adjusted it back to 8.
I did it based on Barry's instructions (putting a rubber band around the centrifugal advance). When we took it off, the timing did not change, so the springs/weights in the centrifugal don't seem to be the culprit. We donlt have a dial back gun, so we didn't set total timing.
We took it for a ride, seemed to be better, but still had a hesitation.
So I'm guessing it is probably the carb? I did notice that the primaries seemed to be open all the time. Aren't they supposed to close?
I did it based on Barry's instructions (putting a rubber band around the centrifugal advance). When we took it off, the timing did not change, so the springs/weights in the centrifugal don't seem to be the culprit. We donlt have a dial back gun, so we didn't set total timing.
We took it for a ride, seemed to be better, but still had a hesitation.
So I'm guessing it is probably the carb? I did notice that the primaries seemed to be open all the time. Aren't they supposed to close?
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
Im guessing he's talking about the choke on the primary, not the throttle blades down inside it.
On the bigger picture, I'm still rooting for the accel pump theory. You really have to get a healthy squirt to overcome the sudden acceleration. Someone unfamiliar with what this looks like might think a half-volume spray "a decent 'squirt' " looked pretty effective, where I would be expecting almost more of a "spray".
Does it spray gas from the beginning of the stroke to the end? Or only during part of the movement of the accelerator pump?
Im pretty suspect of an accel pump that hasn't been replaced in 35 years.
On the bigger picture, I'm still rooting for the accel pump theory. You really have to get a healthy squirt to overcome the sudden acceleration. Someone unfamiliar with what this looks like might think a half-volume spray "a decent 'squirt' " looked pretty effective, where I would be expecting almost more of a "spray".
Does it spray gas from the beginning of the stroke to the end? Or only during part of the movement of the accelerator pump?
Im pretty suspect of an accel pump that hasn't been replaced in 35 years.
Last edited by Droshki; Nov 24, 2008 at 01:22 AM.
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
I did it based on Barry's instructions (putting a rubber band around the centrifugal advance). When we took it off, the timing did not change, so the springs/weights in the centrifugal don't seem to be the culprit. We donlt have a dial back gun, so we didn't set total timing.
