351 Ford Motorsport Engine Dies

cobrabuilderI · #1 (**permalink**) 11-19-2004, 07:34 PM

Problem for your consideration if you could help me out friends:
Was running the snake along the West Coast of the Gulf of Mexico this Friday afternoon (Clearwater beach) and had run it for 30 min. or so. It konked out. I mean it was running fine, then the engine died. Sputtered for a bit then died. Pulled it into the parking lot of a rather seedy motel along the beach (had several lookers at the beast- "Wow you're lucky to have that!" was one) and checked the electrical which I knew wasn't it because all was running fine. water below 200f and oil p @70 so I knew engine was ok. Called a friend said it had to be no fuel. Turned fuel pump on manually engaged the carb so I could see fuel coming out and VARROOM. It cranked and ran. Was running back home, and it did the same thing as before after running 20 min. or so. Did the same thing as before. Turned fuel pump on, cranked carb till fuel, VAROOM tried to get home- 20 min later SAME THING. Almost got home and it did it again. Was able to get it home. Before I made it home where I stopped there were some guys that helped me out said I didn't need elec. fuel pump- they would run it without. Do you think that might be the problem or the fact that I put regular gas 87 oct. vs. 92 which is all it has known? It is a Ford Motorsport Engine straight from factory. Any insight my friends?

cobrabuilderI · #2 (**permalink**) 11-19-2004, 07:38 PM

Engine is brand new. Less than 500 miles. By the way, what mileage should I retorque heads? Ford says after breakin period but when is that?

Dennis Kelley · #3 (**permalink**) 11-19-2004, 07:39 PM

sounds like a fuel pump thats getting weak. Ditch the electric and put a manual carter or ebrock high volume. I have had no luck with electric pumps of any kink. Just my opinion.

cobrabuilderI · #4 (**permalink**) 11-19-2004, 07:45 PM

You mean this Holley Elec. will get weak after 500 miles? Wow.

Tommy · #5 (**permalink**) 11-19-2004, 08:47 PM

Although this sounds like a fuel delivery problem, I wouldn't jump to the conclusion that the problem is just the fuel pump. Here's a few other things to check.
1. Is the fue pump near the tank and lower than the tank? Electric pumps are better at pushing fuel than pulling it.
2. Does your fuel line run near enough to the exhaust to cause vapor lock (boiled fuel)?
3. Are your float levels set correctly? If the primary float is set too low, you could temporarily exhaust the fuel supply.
4. Is there a fuel filter between the tank and the fuel pump? This can sometimes make it difficult for the pump to draw fuel.

Good luck solving the problem.

Dennis Kelley · #6 (**permalink**) 11-19-2004, 09:06 PM

Cobrabuilder1

I didn't know that your initial post said that the fuel pump only had 500 miles. Sorry for posting my opinion. Take it with a grain of salt. Didn't see you additional post for some reason.

CowtownCobra · #7 (**permalink**) 11-19-2004, 09:16 PM

Hmmm... nothing like a good mystery.

Could be a clogged filter. If the car only has 500 miles on it too, it could be the tank has spit out a bunch of plastic left over from manufacturing. My Lone Star did that when it was new. It has 2 filters, one right outside the tank, and another up near the engine. I would change both, not much of an investment for peace of mind. If it has an MSD 6 in it, you might also have a bad unit, I've seen a lot of MSD's do what you are describing.

Let us know what you find.

cobrabuilderI · #8 (**permalink**) 11-20-2004, 04:49 AM

After sleeping on it last night, and looking at your posts, which are great, I do have a filter right outside the tank, But would that have caused this situation? It seems hard to beleive. But the boiling fuel is interesting.... humm. It seems that after the car cools for just a bit, it would start pumping. Reason being that this is the longest trip I've taken it on. And it did it like 35 min. 20-15-10 min. the fuel line comes up the drivers side frame, up to a 90 degree fuel fuel regulator (Holley supplied) that has not been messed with the setting, closest it gets is to the heads maybe 4" then over the vacuum collar of the distributor then makes the turn to the carb.. Like mystery huh? I prefer Action myself. HA>

NeedAntiVenom · #9 (**permalink**) 11-20-2004, 05:14 AM

CobraBuilder,

When it stops pop the air filter and work the throttle - are the squirters tossing fuel in the the venturii? If not it is fuel delivery problem, otherwise it is ignition.

For fuel delivery:
Pump to close to something hot (header, exhaust, etc.) causing it to overheat. This is not likely a clog as it would show up very quickly not after minutes. It could be boiling in the fuel line if it runs near the headers.

For ignition:
Is the MSD inside the engine compartment? If so mount it under the glove box - heat can kill them - many posts to that effect. If you shield it with some insulation in the side facing the engine and it runs longer - that might be it.
The pickup in the distributor may be acting up with heat.

Try to rule things out one by one.

Ron61 · #10 (**permalink**) 11-20-2004, 05:22 AM

BB1,

I have ran a Holly Blue Pump for over 6 years with no poblem at all after the first 100 miles. I had sort of what you have and called the Holly Tech line. First thing they asked me was if I had a filter between the pump and tank. I told him yes, the one they sent. He toldme to take it out and throw it away and not put a filter there, the pump has a screen in the inlet that will catch anything the filter would. I took the filter out, checked to be sure the screen was in there and have never had a problem since. After removing the filter I did have to readjust my pressure regulator as it immediately went to 14 pounds at the carb and they want 6 to 9 pounds normally. I do take the line from the tank off occasionally and check the screen to see if it has anything and only once I found a small piece of dirt.

Ron

cobrabuilderI · #11 (**permalink**) 11-20-2004, 05:57 AM

Ron- I have the same deal... The filter is between the fuel tank and the pump which is mounted a hair below the tank. My fuel line though goes over the top of the axile where I have the filter mounted on the top. I'll take the filter off this afternoon. Holley also sent me the pressure regulator that is installed near the frame where it makes the 90 turn up to carb in front of engine- This regulator has been set and I haven't messed with it. if I chose to mess with it (IF IT AIN'T BROKE DON'T MESS WITH IT) how do I check the pressure on the fuel delivery. I firmly beleive this is a fuel delivery problem.

cobrabuilderI · #12 (**permalink**) 11-20-2004, 06:02 AM

Gents-
How does your fuel line run on the rear end- mine is from tank up over axile to fuel fiter then back down to fuel pump. Has anyone put it below axile- logically it doesn't sound good in my opinion as stuff could hit the line but stuff could hit the line under the car- any thoughts?

CowtownCobra · #13 (**permalink**) 11-20-2004, 06:27 AM

cobrabuilderI :

My fuel line stays low as it runs from the bottom of the tank to the Holley blue fuel pump which is mount to the frame rail.

What was the fuel level in the tank when this happened? If it was less than a quarter tank then this might be interesting.

You should probably invest in a fuel pressure guage, put it right at the fuel regulator, gauge on one side, ouput to the carb on the other. Most carb's want about 5 lbs of pressure.

relaxinrob · #14 (**permalink**) 11-20-2004, 06:39 AM

We had the same thing happening on my dad's Cobra......thought it was a fuel pump or carb, but it ended up being a bad coil that broke down when it got hot in the engine compartment.

trularin · #15 (**permalink**) 11-20-2004, 07:28 AM

I ran my line over the axel.

Sounds like you might have a filter/pump problem. A temporary fuel pressure guage may help with determining what is wrong.

Connect it and monitor the pressure as you drive. When it dies, see what the pressure is at the carb.

Just a thought

Ron61 · #16 (**permalink**) 11-20-2004, 08:57 AM

CB1,

My fuel pump is mounted just in front of the tank on a frame rail that goes across there. My pickup is through the top of the tank and my line to the engine goes along the left side frame rain and is protected all the way. As for the regulator, Imounted it in the engine bay at the front of the engine and got a pressure gauge that goes in it. When I have the car running and the hood open, I can adjust my pressure from zero to the full 14 pounds, but Holly said to run 6 to 9 pounds. Then I have a clear inline filter between the regulator and carb. I can give you the number of the regulator that I have and the gauge that screws into it. The gauge stays in all the time by the way.

Ron

Curt C. · #17 (**permalink**) 11-20-2004, 10:43 AM

Vaporlock? Fuel getting too hot and boiling. This will cause the motor to stop from lack of fuel. get the motor real hot again, turn it off and then observe the carb. You can generally see vapaor/gas being spit out of the squirters from the boil. A half inch phoenelic spacer will begin to help solve if this is in fact the problem.

CCX33911 · #18 (**permalink**) 11-20-2004, 10:56 AM

I assume the carb has sight glasses in the bowls. Check level in carb just after it dies. Also check squirters (as recommended before). If the levels are good and squirters are good it is not a pump problem. I guess it still could be vapor lock though. I would also guess that the coil is breaking down while hot. Does it restart right away or do you have to sit a while?

Ibr8k4vetts · #19 (**permalink**) 11-20-2004, 12:58 PM

My vote is vaporlock!.
Mike

cobrabuilderI · #20 (**permalink**) 11-26-2004, 04:29 AM

Replaced with a Holley Red - if this one goes bad after running I'll goto mechanical. Everything is OK. THANKS>