QuestionDick
It is a standard three in the tree.By lugging I mean it loses power and surges? ahead in short frequent intervals.
By low fuel I mean it wont start when the gas tank is almost empty.-------------------------
Followup To
Question -
Dick,
What are the signs of a faulty fuel pump?
On my 64 Pontiac 230 6cyl.,I get 'lugging' on low fuel.
Also the engine lugs just after I shift to second and increase speed.
On another note,I have been told that since this is a rebuilt engine-new rings,gaskets,etc..the fuel economy will be poor and I should take it easy until it gets 'broken in'. True?
Answer -
To answer your second question first, I would need to know exactly what was done to rebuild the engine. The parts that are most critical for breaking in are the cylinder walls and piston rings, but this is only if the cylinders were re-bored to an oversize, and new rings were fitted. If this is what was done to your engine, the best way to break it in is to run it at fast idle (about 1500 RPM for a half hour or so), then begin driving the car normally, but gently for the first 500 miles. The person who rebuilt the engine may have done the initial half hour of fast idle before giving you the car to drive.
By driving gently, I mean to avoid full throttle operation, and avoid steady speeds. Vary your speeds frequently, and do not exceed about 55 MPH for the first 500 miles. Then after that, you can gradually increase your maximum speed to normal traffic flow, and begin to drive the car as you will in the future. Change the oil filter and oil at 1000 miles or sooner, and then again at around 2500 miles, then you can safely go to 3000 to 3500 miles per oil and filter change from then on.
As for fuel pump failure, the usual symptom is to have the engine lose power almost completely on a long uphill pull, yet the engine will idle and run on flat ground just fine. This is also the same symptom as for a plugged fuel line or a clogged fuel filter. If you have a transparent fuel filter, you will see air bubbles coming in with the gas, probably, if you have a bad fuel pump.
I'm not clear on what you mean by "lugging on low fuel" - perhaps you could just describe what you feel and hear, and when, and maybe I can help you decide what is wrong.
Also, please tell me what transmission is in the car (automatic or manual), and has anything been changed from stock (especially the gear ratio in the transmission or rear end).
Dick
AnswerThe loss of power sounds to me like a carburetor problem. Has the carburetor been replaced or rebuilt, and do you know that it was OK before the rebuild?
I think you need to take the car back to whoever installed the reubuilt engine and have him check it out. There are so many possiblities here that I could type for an hour and never hit the right one.
The failure to start could be due to lack of fuel, but the fuel pump doesn't know how much fuel is in the tank - it will work the same no matter how full the tank, as long as there is SOME fuel in the tank.
Maybe your fuel gauge is wrong, telling you have some gas left when it is actually out of gas?
It is pretty normal for the car to be hard to start after it has sat for a while (like a few days). This can be caused by fuel evaporating or leaking out of the carburetor, but it is not related to how much fuel is in the tank.
Next time it won't start, take the air cleaner off and look down the top of the carburetor to see if you can see a squirt of liquid gas when you operate the accelerator linkage. If you can, there is gas in the carburetor, so lack of fuel isn't your problem.
If there is no gas in the carburetor, put an ounce or so of gas down the main barrel of the carburetor and put the air cleaner back on, then try to start it. If it starts, the problem was lack of gas.
If, when the engine is cold, the choke flap on the top of the carburetor isn't closed far enough, that is probably your problem, not lack of fuel. You need to get someone to adjust your choke for winter driving.
These Canadian Pontiacs are somewhat strange to us down here in the southern states - I don't know if you have an automatic choke, but my guess is that you do - it may be not operating, or it may be misadjusted. Surely whoever installed your rebuilt engine could and should straighten that out for you easily. The choke flap should be closed when the engine is cold, and slowly open as the engine warms up. Sometimes the linkage gets sticky, but if the carburetor has just been rebuilt, that should not be the problem. Rebuilt carburetors are well known for causing problems like this - depending on who rebuilt it!
Dick
