Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









67 mercury cougar 390 hard to start


Search for (search options)
 



dave 1967
Novice

Mar 8, 2009, 11:37 AM

Post #1 of 14 (2497 views)
67 mercury cougar 390 hard to start Sign In

          my 67 cougar has a 390 with a holly 750 and it was running fine until halfway through last year when it just seamed really hard to start almost like it was fludding itself. when i got it to start by use of jumper cables it would run fine then i would drive it for about a mile to work shut it off then try to start it but it would crank over very hard like it had a dead battery but still had 13 volts. now i try changing the carb to a edelbrock but same thing happened I also changed the fuel pump,points distributer,coil,altenator,voltage regulator. the stupid thing is i had the mufflers change to bottles and thats when it started happening it can't be from lack of back pressure can it? . maybe the starter has to much resistence or the cable going to it?


Loren Champlain Sr
Veteran / Moderator
Loren Champlain Sr profile image

Mar 8, 2009, 6:42 PM

Post #2 of 14 (2491 views)
Re: 67 mercury cougar 390 hard to start Sign In

Dave; Does this present itself when the engine is cold? Or, just when hot? This doesn't sound like a carburetion problem and definitely not an exhaust problem. If it does it mainly when hot, then I'd look at a few things:
1) Ignition timing. If over-advanced, will cause a starting issue. Disconnect the coil wire and see how it cranks.
2) Have the battery load tested. Check the cables; The one going from the solenoid to the battery, solenoid to the starter, and the ground cable to the engine block.
The 390 takes a lot of amperage to turn that baby over. If all the above is okay, then have the starter draw tested (in the vehicle). Another consideration; If you are running headers, it's possible that you are getting too much heat transfer from the headers to the starter. You can buy heat sheilds for that purpose.
Loren
SW Washington


dave 1967
Novice

Mar 8, 2009, 7:04 PM

Post #3 of 14 (2490 views)
Re: 67 mercury cougar 390 hard to start Sign In

Thanks for all the good tips will try them,but might be a bit slow no heat in the old garage lol. The car most of the time will start when cold but if you even touch the gas seems like it just floods, it has electronic choke so can't see that being an issue. it'll just fire once then keep crankin till the battery drains, tried three different batterys. When it's hot yes it does seem to be the worst crankin reallllly slow then stops, crank to much and the fn solinoid starts to smoke. Can't remember how to test the cables from the battery, probably the best bet seeing how they put the battery in the trunk!. The timing i did to spec when i change the distributer, then again when i purchased the car i was told it had 428 gt heads from a gt grand torino and the matching 4 speed toploader. think the ignition timing might be different? To draw test the battery how does that work again I do have a multimeter and a extra pair of hands. ps no headers hard enough changeing plugs.


(This post was edited by dave 1967 on Mar 8, 2009, 7:16 PM)


Loren Champlain Sr
Veteran / Moderator
Loren Champlain Sr profile image

Mar 8, 2009, 7:37 PM

Post #4 of 14 (2481 views)
Re: 67 mercury cougar 390 hard to start Sign In

Even though it's an electric choke, it could be adjusted too rich. Also, the choke pull-off, which is vacuum operated, may not be working. The choke should open about an 1/8" as soon as the engine starts. With the engine cold, check the tension on the choke butterfly. It should be just enough to hold it closed. If not, loosen the three screws on the black cover and rotate it accordingly.
The timing will have to be done, really, hit or miss. You can start at specs, which is probably around 6 degrees BTDC. You can advance the timing a degree or two at a time until it pings under a light load, then back off a degree or two until the ping is gone and your starting problem is gone. But, you can tell if it is timing by disconnecting the coil wire when it acts up. If it cranks over okay with the coil wire disconnected, then it is over advanced. Retard the timing until it will start okay. By retarding the timing, you will lose some performance, but overall, it's worth it.
If it is timing that is causing your problem, that is caused by pre-ignition. You want to do whatever you can to lower the combustion temperature. Highest octane fuel available will help. (the higher the octane, the cooler it burns..sounds backwards, huh?) Make sure the point dwell is correct. Every two degrees of dwell will change the timing one degree. Over advanced timing will just add to the problem. Cooling system is critical. You are running a big block in a very tight space. Keep that sucker cool.
Another heat getter is a lean condition. Make sure that the air/fuel mixture is correct. A lean condition can cause heat which adds to the pre-ignition problem. Takes more spark to fire a lean mix.
Loren
SW Washington


dave 1967
Novice

Mar 8, 2009, 9:22 PM

Post #5 of 14 (2477 views)
Re: 67 mercury cougar 390 hard to start Sign In

Thanks Very good tips and I will check all of them, it just doesn't make sense that one day out the 60 i drove it that year it decided to do this without changing anything


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Mar 9, 2009, 2:07 AM

Post #6 of 14 (2473 views)
Re: 67 mercury cougar 390 hard to start Sign In

Just a side note:

Battery cables probably have been replaced over the ions with this. Now that copper is so expensive they sell a lot of junk out there that doesn't carry the amps well. Even back then we were upping the gauge (or lowering the #) to #1 gauge fine strand for high compression monster motors like that.

"Solenoid smoking" !! There's another item that might have been replaced for junk sold now. Orig would have been better metals. NAPA is pretty good at getting OE rated stuff or try marine duty stuff for things like that.

Neat old car and remember them pretty well. More engine than the body could handle!

T



dave 1967
Novice

Mar 9, 2009, 4:21 AM

Post #7 of 14 (2469 views)
Re: 67 mercury cougar 390 hard to start Sign In

good point thank you , my old 5.0L Ranger whent through a solenoid every time after sitting through a winter, I'll have find a heavy duty one regardles. Probably should get the battery back in front will take some messing with then buy new cables


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Mar 9, 2009, 5:03 AM

Post #8 of 14 (2467 views)
Re: 67 mercury cougar 390 hard to start Sign In

"Battery back to the front"

Where did you put it? I know you don't need to take space or have the extra weight up front but the length of cable matters as well and gauge matters all the more.

Also note: The batteries made for closed quarters should have vents to outside air - some that came that way (not this car) had tubes to hook up and the battery case was made for that. Dunno if gel cells use any venting or need any if you go that way??

T



dave 1967
Novice

Mar 9, 2009, 3:31 PM

Post #9 of 14 (2460 views)
Re: 67 mercury cougar 390 hard to start Sign In

I agree with you the battery should be in the front which is the safest (not sitting by the gas tank or leaking fumes in the inside of the car) The battery was in the trunk when i bought it. The only reason I can see why, is they mounted a mallory ignition coil in the spot where the battery was which is not working Or the battery tray was rotted out.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Mar 9, 2009, 6:49 PM

Post #10 of 14 (2453 views)
Re: 67 mercury cougar 390 hard to start Sign In

Somewhat off the topic:

May I suggest you just get the OE distributor + points right on target and forget ign beef up junk. Granted - these suckers were newer when I was driving them - a 1967 as yours and the 68 427 "R" code GTE (fastest anything I've ever been in) with plain points that would tear the a$$ off of anything! Faster from zero to choke on your own tongue from the "G" force of acceleration than should have been street legal from the factory!

Side note: That 68 Cougar XR7-GTE 427 auto (factory trick C-6) no less lied right on factory chromed air cleaner boasting 390HP - found later that Ford purposely lied and it was more like 540 BHP!! Now I know why my eyes are still stuck to the back of my head!

Owned a 69 Lincoln - first high compression 460 and prior owner went nuts with ignition garbage to improve fuel economy with funky crap all over the place. Threw all that junk out and it was fine for the 14 or more years I owned it - same MPGs and ran better!

These can do just fine with points as they aren't trying to do motorcycle RPMs but rather stump pulling torque. The only improvement prior to common use of electronic ignitions was the dual point job which only really tricked the spark to increase duration - aftermarket for many sold by Accel. Mopar made some OE back when I think.

The problem was so few had the patience to just set the points right and check periodically - they worked fine,

T

Ps: I think Ford made the first electronic ignition as an option and called it "Perma Tune" in the mid 1960s......



dave 1967
Novice

Mar 10, 2009, 4:38 AM

Post #11 of 14 (2445 views)
Re: 67 mercury cougar 390 hard to start Sign In

I didn't think i would run in to a ford fan, finally. The distributer I Had bought was a remanufactured with points. My knowledge with the muscle car era sucks. As a (young) licensed auto body technician I love the lines on this cougar, different than the mustang which is still everywhere up here.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Mar 10, 2009, 4:59 AM

Post #12 of 14 (2443 views)
Re: 67 mercury cougar 390 hard to start Sign In

Excellent on the dist! A good reman should be all set to go and perfect - just set timing.

Know that when new this high compression big block required premium fuel. The regular of the day was better than what's sold as premium today and low octane works against the starter some if there's the slightest tendency to fire early.

You can get an idea of what better cables and high amp battery would behave like using quality jumper cables now. Only original cable left would be from solenoid to starter then.

Just notes: Copper is the best conductor of electricity. The finer the strands the more contact it will make at the crimped on ends even if factory done. Fine strands don't tend to break inside as much either and there is some constant motion between solenoid and starter on this type. Bat to ground moves some too. It's kinds like the rating of household cord for a vacuum cleaner is super fine strand vs that for a lamp - really!

Copper got pricey and lead got hit for use in the cable ends. It was better but required some periodic maint too. Replacements might have used a different metal for everything in the cable that just might not have the ability.

The starter is happy with a good strong source to it. It actually get VERY hot when low amps are delivered and can hurt it. Hence almost everything uses a spring loaded solenoid to "flutter" when inadequate to prevent that. The better the battery and cable the better. This and all starter can be taken apart and brushes to contacts cleaned up. Older than this you could put them in a lathe! Ok - nuff on old :-)

To add to high compression issues then was lead in fuel. Now the high fuel use of even unleaded can make compression even higher with carbon build up making even more work for the starter and sometimes near unstoppable ping/knock when under some load. Usually a good hard run would clear that out.

Just fun from the good ole days,

T



dave 1967
Novice

Mar 10, 2009, 3:42 PM

Post #13 of 14 (2437 views)
Re: 67 mercury cougar 390 hard to start Sign In

good to know thanks I did double check point gap with a feeler guage and it said it was good. Maybe you can help me choose an after market clutch and posi is there any you can recomend. My clutch is shot and the pinion bearing is worn out, I can wiggle the shaft like 3mm sorry 1/8 don't Know if you do metric. P.S. sorry just read Way2old's message on asking Questions but it took me awhile to find a good site.


(This post was edited by dave 1967 on Mar 10, 2009, 3:52 PM)


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Mar 10, 2009, 3:58 PM

Post #14 of 14 (2432 views)
Re: 67 mercury cougar 390 hard to start Sign In

TMK - Cougar didn't offer a standard trans! Anything is possible but bet it's to a Mustang set up.

No matter - I'd suggest new stuff - see what available and for t-out bearing try to get US or Canadian made bearing.

What's with the pinion? I simply don't know what rear differential this would have so you'll have to look. If it's what's called the removable carrier type there's two pinion shaft bearings in there and a "crush" washer that I just saw ONE of in my collection of crap the other day! No joke!

If you would - please make the pinion bearing thing a separate thread. If you dunno what type rear end it is try taking a pic and I should be able to look it up. Either that or just look for a tag on it if still there,

T







 
 
 






Search for (options) Privacy Sitemap