1976 Bogging Down
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 1,079
Likes: 1
From: Niagara Falls ON
1976 Bogging Down
STill can't trace my problem. My 1976 L-48 loses power after around 2,000-2,500rpm. I have checked the EGR, the catalytic converter is good, new plugs, wires, coil, cap, and the air filter is good.
The only part that I am not sure of the age is the ignition control module.
Could the vacuum advance cause a problem like this?
Would the transmission have any affect on how the engine will just lose power?
The only part that I am not sure of the age is the ignition control module.
Could the vacuum advance cause a problem like this?
Would the transmission have any affect on how the engine will just lose power?
Le Mans Master
Joined: May 2002
Posts: 5,084
Likes: 786
From: Lebanon Township New Jersey
You need to describe the problem better. Are you talking about in gear, wide open throttle? Does it not rev beyond that point at all. Can you rev it to 5,000 in neutral?
Disconnect the vac advance and plug the carb side of the hose just to test that.
Ignition module usually works or it doesn't, but it's easy to change.
Disconnect the vac advance and plug the carb side of the hose just to test that.
Ignition module usually works or it doesn't, but it's easy to change.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 1,079
Likes: 1
From: Niagara Falls ON
New fuel filter.
I can rev it high in neutral and it runs fine.
When I am driving it lacks power if I am not on a level surface. Trying to go up a hill it really lacks power and it is hard to get it over 2,500 rpm...once it gets around that point is starts to misfire or bog down.
I have checked for spark while the car is in the darkness but can't see anything.
I just put a spare coil in it and that didn't change it.
Runs great in neutral.
I can rev it high in neutral and it runs fine.
When I am driving it lacks power if I am not on a level surface. Trying to go up a hill it really lacks power and it is hard to get it over 2,500 rpm...once it gets around that point is starts to misfire or bog down.
I have checked for spark while the car is in the darkness but can't see anything.
I just put a spare coil in it and that didn't change it.
Runs great in neutral.
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Le Mans Master
Joined: Aug 2010
Posts: 9,272
Likes: 17
your problem isnt in your carb. its in the lines getting fuel to it. find the one thats restricted. if your carb. works fine when its not under load, its not the carb.
on mine that molded line that goes from the hard line on the frame to the fuel pump, got soft and when accelerating sucked almost closed and restricted fuel flow. I replaced it with a regular fuel hose and that kinked cause it wouldnt make the bends. I replaced that with the molded version and fixed the issue
on mine that molded line that goes from the hard line on the frame to the fuel pump, got soft and when accelerating sucked almost closed and restricted fuel flow. I replaced it with a regular fuel hose and that kinked cause it wouldnt make the bends. I replaced that with the molded version and fixed the issue
Last edited by oldalaskaman; Aug 12, 2012 at 10:32 AM.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 1,079
Likes: 1
From: Niagara Falls ON
Cat converter hollowed out
I have the proper lines on the fuel pump. I changed the fuel pump because I wasn't sure how old it was. I had a mechanical fuel pump fail on me in a tunnel was I was in university so I am hypersensitive fuel pump failure. For the low cost of a fuel pump and the unknown age of the one that was on the car I didn't mind throwing money into parts.
The timing was set at 6 degrees, just as the manual says.
I tested the vacuum advance and it seems to be working.
Air filter is good (I took the car to a hill around the block without the filter it and it still lost power)
It is raining now so I will spend my time reading and looking for the right solution.
I have the proper lines on the fuel pump. I changed the fuel pump because I wasn't sure how old it was. I had a mechanical fuel pump fail on me in a tunnel was I was in university so I am hypersensitive fuel pump failure. For the low cost of a fuel pump and the unknown age of the one that was on the car I didn't mind throwing money into parts.
The timing was set at 6 degrees, just as the manual says.
I tested the vacuum advance and it seems to be working.
Air filter is good (I took the car to a hill around the block without the filter it and it still lost power)
It is raining now so I will spend my time reading and looking for the right solution.
Le Mans Master
Joined: Aug 2010
Posts: 9,272
Likes: 17
if you have an air compressor, remove your gas cap, blow air from the pump to the tank, if your sock is plugged it will remove it from the end of the line, crude but effective, then put a filter in the line.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 1,079
Likes: 1
From: Niagara Falls ON
I suspected the float inside the carb wasn't floating well anymore. I tested my theory by putting a spare carb in that I had rebuilt just for such an occasion. Seems that may have been the problem. Now I get the rebuild the other carb as a winter project.