Mercury Cougar Owners banner

1 - 11 of 11 Posts

·
Registered
Joined
·
74 Posts
Discussion Starter #1
Hi again all!

My 71 with the 351-C, 2V, has recently started doing something that I would like to get your diagnosis on, or at least your best guess! :)

If I am coasting down a hill, or just barely accelerating, the car feels like it is struggling to run (chugging exhaust note, vibration, etc). If I am going uphill or just getting on the gas a little bit harder it clears up and runs fine. I should also mention that when the car is running rough the tach is jumping up and down.

Last time it acted similiar to this, it turned out to be the fuel pump. That is going to be my first place to start, but thought I would see if you all had any other ideas just in case the pump doesn't turn out to be the culprit.

Thanks in advance!

Dale
 

·
Registered
Joined
·
11,950 Posts
eh, could be many things....check your oil quick to make sure it doesn't smell like gas and isn't way overfilled. Otherwise it sounds like maybe it's a carb or vac related problem of some kind maybe....
 

·
Registered
Joined
·
1,399 Posts
Vac is usually a catchall with the older engines. Don't overlook electrical. At low rpm the alternator is turning slower thus can produce weak spark. Then there are worn points if you are running a mechanical distributer. Typically a fuel pump problem manifests at higher ram because it cent keep up. Coasting there should be enough in the carb to let the car idle regardless of pump pressure.
List if things to check
1. Battery. 12v ish car off. 13.8v to 15v car running (due to charging from alternator)
2. Choke position. Not enough air = chugging. Make sure it flows open closed and not sticking.
3. Fuel pressure. Rent or barrow fuel pressure gage from the auto part store. They should have the specs too.
4. Timing and points.
5. Vac. Again, rent the gage. Also can use carb cleaner to look for leaks but be careful. Flammable = no eyebrows.

This should be a good start. Let us know the results.
 

·
Registered
Joined
·
74 Posts
Discussion Starter #8
Re: Fuel pump? Your advice please...UPDATED

Hi all,

Thanks for all your advice. Looks like it was a point problem. Got that rectified and now all is well!!

Thanks again!! :)

Dale
 

·
Registered
Joined
·
42 Posts
Hey Dale, throw out those points and get a petronix ignitor (just replaces old points) from yer local shop. Takes 10 minutes to install and you never needs to worry about points again. I just did this on my 351C - 2V (4 brrl carb) setup and it works awesome! Costs about $100.00
 

·
Premium Member
Joined
·
268 Posts
Hey Dale, throw out those points and get a petronix ignitor (just replaces old points) from yer local shop. Takes 10 minutes to install and you never needs to worry about points again. I just did this on my 351C - 2V (4 brrl carb) setup and it works awesome! Costs about $100.00
$100 well spent!
 
1 - 11 of 11 Posts
Top