[DeTomaso] Engine run anomalie

forestg at att.net forestg at att.net
Wed May 13 19:50:17 EDT 2009


Boyd,
That should be enough fuel pressure. I'm leaning toward an ignition problem but here is what I would do first. The next time it won't fire stop, remove the air cleaner, open the throttle and see if the accelerator pump gives a squirt of fuel. If it does then start checking ignition system.
Forest
-------------- Original message from boyd casey <boyd411 at gmail.com>: -------------- 


> I have been having a recurring problem with my car. It is a 73 L that is 
> not completely stock, Edelbrock intake, holley 650 w/ manual choke , 
> MSD 6AL, MSD low profile distributor, MSD "blaster "coil, All the MSD stuff 
> is new including wires and new plugs. I have recently added a" Fram "racing 
> fuel filter, a small " inline" gas filter ( so I can actually see the gas), 
> a fuel pressure gauge. The problem is the car will start and run and seem 
> okay. If I only drive it around the block I never have a problem. If I drive 
> it a few miles I don't seem to have a problem ( Unless I turn it off) when I 
> turn it off it won't re start. I thought I had a fuel tank debris problem. I 
> have removed the fuel gauge sending unit, fuel out let twice 
> and completely drained and vacuumed the tank to pick up any debris. I didn't 
> find any evidence of any particulate mater and the brass screen at the end 
> of the fuel pick up is intact and did not show any signs of blockage. I have 
> noticed that when my engine won't start my fuel pressure gauge stays showing 
> 4.5 lbs of pressure( even though the engine is not running) that made me 
> think I had picked up some debris and that it was blocking the fuel inlet 
> and that the debris was being held in place by the vacuum created by the 
> fuel pump. I installed a vent line using a "T " connection from mu fuel 
> line between my fuel filter and the intake to the carb and another "t" 
> connection in the vent line. I put a small ball cock valve in this line so I 
> could release the vacuum and "drop" any debris being held by the vacuum. 
> This works but not immediately. The pressure on the fuel gauge drops to zero 
> but the car still won't start. usually after around 45 minutes the car will 
> start. It occurred to me today that perhaps the problem is not a clogged 
> fuel line but a blocked Vent line. If the gas tank is not vented won't that 
> create a problem as more and more gas is sucked out of the tank and the 
> vacuum build and since no air is entering the tank it becomes increasingly 
> difficult and eventually impossible for the stock mechanical fuel pump to 
> suck up any gas. Does this make sense? If this is the case is the remedy in 
> the gas cap or the vapor separator assembly Aside from the vent line that 
> terminates there the other connection on top of the gas tank? Also Since I 
> don't have the original air cleaner or any of the vacuum operated emissions 
> devices do I still need to keep the charcoal canister? The return from the 
> canister to the air cleaner no longer exists. My concern was that if the car 
> were to have the misfortune of winding up in an inverted position would the 
> vent line to the canister prevent fuel spillage. If not is there any reason 
> not to have the vent line open to the air instead of the cannister( which I 
> would like to remove it if is not serving a useful function.) If this is an 
> issue that can be remedy with a new gas cap do I have to buy a "pantera "gas 
> cap ,or is there a "normal " vented gas cap I can use?Thanks, 
> Boyd 
> _______________________________________________ 
> 
> Detomaso Forum Managed by POCA 
> 
> Archive Search Engine Now Available at http://www.realbig.com/detomaso/ 
> 
> DeTomaso mailing list 
> DeTomaso at list.realbig.com 
> http://list.realbig.com/mailman/listinfo/detomaso 



More information about the DeTomaso mailing list