I'm sorry I have'nt posted a thread in a long time. I've been real busy with work. Do you guys remember me ranting about no one wanting to hire a 20 year old mechanic? Well I finally landed agood job doing what I love to do. Anyway, I have'nt driven the mav in about a month or so because I cant keep the damn thing running! It just happened out of the blue one day? It has a real loss of power on the highway, It runs ok at idle but as soon as it's in drive it shakes and sometimes stalls? It seems to happen when the engine gets to operating temperature. I can keep it runnning at a stop light if I put it in nuetral and feather the gas. To explain it more deeply, If I have it in gear with my foot on the brake, it sort of surges? I took the carb off (edelbrock 600) and made sure the floats werent sticking and checked thier drop. They are fine? I went to an HEI setup a while ago but I have'nt had any problems with it. It is acting just like it did back when I had piont igntion, and the pionts were too close together. it had no power and would stall under load when at idle. But I doint have pionts anymore I have HEI? The more advise I can get the better THanks in advance, and sorry for ditching everyone for a few months Adam in MIchigan.
It kind of sounds like the car is starving for fuel. Have you checked the fuel filter? There may be some dirt interfering with the fuel system.
I've got a clear filter so you can see through it. Nothing that I can see is clogging it? thanks. I just drove it some more and it is definatly when the engine gets hot. When it's cold all is fine? Also, closing the choke alittle does'nt help. I've adjusted the mixture screws and messed with the timing to see if that does anything..........it does'nt? I also upped the idle to try to keep it running when stopped. It still shakes and surges, but at a higher rpm of course. I checked for vacuume leaks and found none.
Mav Stalling Just a thought I had, from experience with Edelbrock carbs and headers in a closed engine compartment, the heat factor is so great that fuel actually boils in the bowl. Might try a thermal spacer under it or could be a vapor lock problem. Have you checked the fuel pressure cold/hot etc? Some things I ran into in the past. Electric pump maybe??? Also had a Dodge that the rubber fuel line on the filter would collapse when hot and starve the engine, how about the line to the modulater? Hope you find the prob. let us know the outcome.
possibly just bad idle adjust your screw? mne didnt "stall" but it would jump and shake and go crazy at stop lights, i fixed the idle and its perfect now, nice and smooth/?
I think Old Guy is close. Is your gas cap vented? Did you plug the line from the gas tank to the charcoal cannister? Did you check for vacuum leaks hot? It sounds like more of a fuel/vacuum problem than ignition.
I have an electric fuel pump with a pressure regulater st at 5 psi. I've tried the plastic spacer (1 inch) But it didnt help. It helped absorb heat tremendously, but did'nt do anything for the shaking and stalling. All my fuel lines are new. And I have adjusted the idle screw to try to level it out. I also had it in gear with my foot on the brake while giving it gas to put it under load. It did'nt stall then (because I was giving it gas.) I really do'nt know what is going on? Any other I Ideas? I truly appreciate all your help and hope to see you guys at next years roundup God willing of course.
Sounds like it could be a vacuum leak. It's running ok cold because the choke may be masking it. Check for a loose hose or a bad carb gasket.
I have a manual choke. and the engine starts up cold and really does'nt seem to need the choke closed at all when first started. Maybe because the engine's new? The carb gasket is also new and not torn or anything. Thanks for the advice, I'm afraid I might be sol for while with this problem? Well if anyone else comes up with any Ideas let me know. Thanks Adam Michigan
run a compression check to be sure it is not a head gasket. Run a vaccum test to be sure you don't have a leak. when the engine is off, move the accelerator and look down the center of the carb to be sure that your accelorator pump is working correctly
