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Wyatt

New member
Joined
Oct 10, 2017
Messages
4
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0
Location
Atlanta
My Car
1971 Mach 1 351 Cleveland 2v
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     First off this is my first post to this forum, My car is a 1971 Mach 1 with a 351 Cleveland 2v and a fmx transmission. I bought this car in 2012 when i was 12 for $2300 (with the help of my dad) when we got it, it was a all numbers matching car. My dad and i rebuilt the motor and bought a rebuilt AOD transmission we put the motor in the car and got it ready to start. We tried starting it but it just clicked so we checked the battery ground but still nothing. so at this point we thought it was a bad starter so we bought a brand new summit high torque starter, with this new starter the motor turned over but very slowly. We were stumped so we checked the compression and sure enough 0 compression across all 8 cylinders, fed up with the motor we racked it and we bought another 351 cleveland 2v that was rebuilt for $1000. Thinking that this was the solution to our problem we attached the transmission and dropped it into the car. We cranked it over and it fired right up but then came the problem of it not idling, the only thing we did to the motor since we bought it was put the intake on which we thought was the problem. So we pulled it off and made sure it sealed right which we did successfully(not easy) and tried to fire it up again. It still would not idle and we knew it wasnt the carb because it was a brand new summit carb but to make sure we put on a holly that we knew worked and still nothing. That leads to the problem we currently still have is it not idling. We have tried about everything electricaly so i dont think it is that. The thing that confuses us is that the timing is set at 40 degrees advanced for it to actually run until around 2000 rpms where it will die, if we try to retard it to around 15 it will not start. So we are currently stumped if anyone knows what the problem could be I would appreciate it alot to hopefully get it back out on the road. 

      To the rest of the car it was origianly silver (it will be repainted eventually the same color) with standard black interior. It came with a tach and dash pack.

 
Welcome from Western Australia

Looks like you got a good deal on your vehicle despite the problems and if I could buy these mustangs here at those prices I would have several of them

Your original starter problem sounds odd in the sense that if you had zero compression it would turn over very quickly just like removing spark plugs when doing compression tests

Perhaps that engine was overheated in the past and was nearly seized or had timing issues?

Your newer engine sounds like you need to check the basics especially timing but also check for vacuum leaks elsewhere. I would first check for top dead centre by removing number 1 spark plug then turning it over by hand while inserting a screwdriver down the plug hole. the piston when at the top should show TDC on the balancer timing mark - if way out you may have timing chain issues where it could be out a tooth or two. If pretty much spot on then check the static timing on the distributor by grounding the spark plug wire, ignition on then turn crank by hand until you get a spark, should be around 8-12 degrees initial timing. Other than that it still could be a carby issue but seeing as you tried 2 carbs would still be looking at timing/vacuum leaks or depending on what ignition setup maybe look there also.

Good luck with it and hope you get to finally drive it, can't wait to drive mine but a long way to go yet.

Perhaps some more experienced member will chime in with some better ideas

 
Welcome to the forum from the Seattle area. Sorry to hear you are having engine issues. I will let other folks weigh in who can better guide you through the troubleshooting process. Ask questions here as they come up, and you will get all the guidance you will need. This is a great community that know these cars inside and out.

Scott

 
I agree with the earlier comment about checking TDC, to make sure the cam timing is correct, and then make sure that the distributor is in correctly by making sure the rotor is pointing at the wire for #1 cylinder when the engine is at TDC. Have you run a compression check on the new engine to make sure you don't have a bent push rod, or bad rings? How sure are you the engine was rebuilt and do you know why it was pulled or not installed? I once knew a guy that changed his oil and then advertised the engine as rebuilt.

Steve

 
Welcome from Virginia. Sounds like great deal. I'm glad to see a teenager taking interest in the old Mustangs! It does sound like a timing issue. Also, if your are running the original style Points in the distributor you may want to change over to a Petronix electronic ignition.

 
Hi From Phoenix. It's great that you are getting into older mustangs. Don't get discouraged!

I assume the engine picture is not 'as running' since the fuel line is not connected.

The firing order looks correct.

I see you have an aftermaket coil. I can't trace from the picture how it is connected. One thing to know is that originally your mustang came with an 'external resistor' coil. The positive wire was special and added resistence providing just a few volts at the coil. There is another type of coil known as an 'internal resistor' coil. An internal resistor coil is expecting close to 12 volts. Verify if your new coil is 'internal resitor'. If it is, with the ignition in the on position, even with the car not running, test the voltage at the coil and see if it is just a couple of volts or not. If a portion of the original wire was used you may have low voltage at your coil. In this situation the engine will tend to run at lower RPMs (the coil still has saturation time) but falter at higher RPM's. Check this first. (It does appear to me in the picture the original wire is laying on the valve cover and not in use)

In the picture almost no vacuum is connected. You want to check for vacuum leaks. Put a cheap vacuum gauge on it and see what kind of vacuum you are getting.

As mentioned above, re-verify that the rotor is pointing towards your #1 plug wire on the compression stroke at TDC. Are you getting any backfire? That will often indicatea 180 degree off timing. Remember, the crank will rotate twice for each spin of the rotor.

When you say the timing is set to 40, is that initial timing? When you increase the RPM's do you see an increase in timing? Can you describe how you are getting your timing values? What kind of timing light and such.

In the above picture I see an electronic choke but it doesn't appear to be connected. During your test runs connect positive power to the choke. This will warm up the bimetal strip inside and 'turn the choke off'. But don't leave it connected all of the time as it will drain the battery over a long period of time. (So it's okay to leave on while you are working on it but not over night or for days)

 
Last edited by a moderator:
Welcome to the forum from North Carolina.

Looks like the guys have you pointed in the right direction. Do the basics with the timing and checks and it will start right up. Fuel, compression and spark at the right time will do it every time. BTW a new anything does not make it right. Carbs can be bad out of the box.

 
Firing order looks good. Is the shot of the rotor exposed where it is pointing at TDC?

Looks like you went back to the Edelbrock. I don't see any obvious unplugged vacuum ports but I do wonder about the clear hose coming off the back of the carb. What's that hooked into?

What Vacuum are you getting at different RPMs? Is it steady or jumping?

What plug gap?

Finally, how did you wire the coil?

 
We finally got it to idle! First we got the motor to TDC then set our timing to static 8 degrees advanced then the thing that solved the idle problem was that the coil wasnt getting enough voltage at low rpms so what i found out by reading online was that i needed to run a wire from the battery to the coil and it fixed out problem. All i need to do now is get a relay so i can shut the car off.



 
We finally got it to idle! First we got the motor to TDC then set our timing to static 8 degrees advanced then the thing that solved the idle problem was that the coil wasnt getting enough voltage at low rpms so what i found out by reading online was that i needed to run a wire from the battery to the coil and it fixed out problem. All i need to do now is get a relay so i can shut the car off. Thanks for all the help you guys gave me!

 
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