351C Issues

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

shaheenk

Well-known member
Joined
Mar 19, 2016
Messages
105
Reaction score
19
Location
South Africa
My Car
73 Mustang Grande Coupe
Hello Mustang Family , I need some advice or assistance. 

I have a 73 Mustang with 351C 2V motor , the motor has just gone through a complete rebuild with new balancer and inside bits. I used a ebay ready to run distributor and set the static timing , we started the car in December and it was running perfectly fine, first turn start and no issues. The car went off to a V8 "specialist" they removed the distributor to change what I dont know but since then the car has had 2 issues. 1. It burnt the center pin on the distributor cap , I have never seen this before and cannot understand why . Before they pulled the Distro they sent a vid of the car and it was running beautifully. 2. Since the new cap is on she will not fire clean and backfires through the intake. I am suspecting timing but setting her on TDC or 10Deg BTDC does the same. Really not sure what could be the issue  , perhaps the pickup in the distro has gone and its not doing something it should. 

 
What kind of ignition? Points, electronic? I wonder if something got damage with the ignition? Did you ask or did they tell you why they removed the distributor?

Sent from my SAMSUNG-SM-G930A using Tapatalk

 
HI Tony , this is the electronic ready to run distributor set up , no points or condenser. I have added the link below from the ebay purchase. 

The story was they were not seeing any oil pressure (bullshit as the light went off) , so they dropped the sump to confirm the oil pickup was connected, then removed the Dizzy to drive the pump to build up pressure. 

https://www.ebay.com/itm/FORD-351C-400-429-460-BLACK-Female-Small-HEI-Distributor-45K-Coil-PLUG-WIRES/190989360791?_trksid=p2485497.m4902.l9144

I am going to head out there again on Thursday and redo the timing manually (stick in plug hole to confirm TDC) as this is how I assembled it the first time 

 
Why did you send it to the "specialist" to begin with?

+1 on checking TDC and timing. Also make sure the firing order is correct, (counterclockwise rotor rotation) when they pulled the distributor they probably pulled some wires off the cap. Also make sure #1 is TDC on the compression stroke. 

Arcing can burn off the center electrode, either from the rotor not making contact or the button being loose or installed wrong.

 
I built the car complete and had a gearbox leak , this was my first "american muscle car" build , I usually do Jap cars and Euro cars so wanted someone to cast an eye over it . When we started the motor in December she was running great , the only issue was the leak from the gearbox front seal. Since I dont have a lift and was not in the mood to pull the box again (did it 3 times) i sent it to them to assist with that and some other small bits. 

They changed my cap from a female to male , changed the boots on my new plug leads to accommodate and now I have the backfire. Its such a pain in the ass 

 
Firing order...

The specialist likely installed the spark plug wires in the wrong sequence, either clockwise, or wrong firing order, or both.

The distributor rotor rotates counterclockwise and the firing order is 1-3-7-2-6-5-4-8. The passenger side cylinder numbering is 1-2-3-4 and the driver side numbering is 5-6-7-8 on left-hand drive vehicles.

 
Last edited by a moderator:
Here is a stupid question , what is the possibility the distro is damaged because they connected the wires to the coil incorrectly  ? Would this also cause the cap to burn out and the distro to be damaged? 

 
No question is stupid, it's only stupid to not ask.

Connecting the module to the wrong terminals shouldn't damage the module if it is designed properly, it should have built in protection. It shouldn't function at all, if connected wrong, so couldn't damage the cap.

Is the spring contact on the rotor also burned/pitted?

 
Well, I'm far from being the best guy to answer this question, but I see a few red flags and that starts with a "whatever it is" distributor. I can only make suggestions based on my own experiences trying to get my 71 4V to run right. Again I emphasize this is on my 71 M code. First off if it were me, I'd buy a DuraSpark set up from someone like Performance Distributors. Not cheap but  a damn good set up..... and it's FORD! Failing that, you could get a Motorcraft reman from Cardone or other remanufacturer. Cardone have a quite good remake of the Motorcraft/Autolite, but it's made in China and has metric screws. I have one as a back up and is curved for 20 deg on the crank (10L slot, .410 wide) with an initial of 14 deg for a total of 34 mechanical all in between 2800 and 3000 rpm. This is what the Motorcraft in the car is set at as well. The sparks come from a Pertronix Ignitor II (red one) with matching coil, 8mm spiral wound wire set and Autolite 25 plugs, but in your engine Autolite 24's might be better suited. Gap (for the Pertronix) is set at .045". The curve is crucial. Most remans  and maybe repops are made to the original specs with a 30 deg crank 15L slot,  plus only 6 deg initial for a total of 36  deg. mechanical. Vacuum was about 6 -10 degrees I believe. I only run 4 deg vacuum approx.

Anyway, hope this helps a bit, good luck and please let us know what you find out when you get it running great.

Geoff.

PS, if you decide to change distributors and want to go back to a more stock style, I have pictures of what I did for mine. Just ask.

 
Last edited by a moderator:
If the rotor isn't also burned it is likely the carbon button either broke apart or fell out.

Do you still have the stock points distributor? If so I would put it back in until you get the car running right, work on one issue at a time, don't compound them.

I agree with Stanglover, if you want an electronic distributor convert to a Duraspark.  Buying a no-name from an unknown vendor is a crap shoot, at best.

 
Don't know who your specialist are but my questions is why did they change the cap over.  Old saying if it isn't broke don't fix it applies big time here.  As Don and Stanglover have mentioned sounds like something in the timing / firing order or could be the dizzy.   You can't go wrong going with a Duraspark. I would also maybe ohms out the plugs wires since they put on new ends.  There are several different way to check but to keep it simple measure a couple of the wires length in inches.  Take the ohm reading and divide by the length you measured  in inches and this will give you ohms per inch.   Ex - 14 inch wire with reading of 4000 = 285 ohms per inch.  You can then use the per inch reading and multiply by the length of the wires and see if it close to the reading you are getting.   Check all of the wires just to make sure they all are good and you don't have a bad one.     

 
Last edited by a moderator:
Thanks everyone for the replies, I have a GMstyle HEI laying about as well which i purchased before going the route of ready to run but it was too big for my airfilter to fit over. 

I am going to take some time and see whats going on . all replies will be checked and replied to .

 
Shaheenk, as I stated before, I'm not the best qualified to answer this, but I honestly don't know why people insist on trying to use GM style anything on our Fords. For starters, it's likely a Chinese knock-off. Do they work, maybe. Are they good, not likely. Do they look ugly, absolutely. That's just MY opinion, but to each his own I guess. In a situation like you're in, after all other tests check out, yes you could try it as it may prove the other dizzy is a problem. However as Don C mentioned, if you have the original Ford dist. with points, try that first. If need be, throw a new set of points and condenser in and set it up correctly. You likely would need to back off the initial timing to below 10 deg (6-8), but it should run way better. It's a matter of elimination to find the real problem. Take your time and yes, it's frustrating as hell and that I AM qualified to answer.

Good luck moving forward.

 
hey Stanglover , support is what I needed and you guys have provided it. I dont have the original Disto that would be first prize. Being out in South Africa also means anything costs double what it would in the US once shipping is plugged in. 

I have taken the day off work to go fiddle with it , I am no pro, but I understand the basics. 

Pretty sure I will find the issue.

Thanks

 
hey Stanglover , support is what I needed and you guys have provided it. I dont have the original Disto that would be first prize. Being out in South Africa also means anything costs double what it would in the US once shipping is plugged in. 

I have taken the day off work to go fiddle with it , I am no pro, but I understand the basics. 

Pretty sure I will find the issue.

Thanks
 Yes, it must be much harder for people living outside the US and Canada, (it's expensive enough here sometimes with very high dollar exchange rates) to get the stuff needed. We have several members in the UK going through the same issues. So, you do what you have to do and in the end, you'll prevail. Just a thought, perhaps one of us has working usable Motorcraft dist. for sale or better yet, donate. That way you may get a less expensive option. Try a WTB ad in the classified section or on F/B. If I had another spare fully working curved distributor, I'd donate it, but alas I don't unfortunately.

There is one item nobody has mentioned on aftermarket distributors and that is the cam gear. It is critical they mesh correctly within very small tolerances. Not only that, but personally,  I don't trust the material they're made from, not even the Cardone Select Chinese remake I have despite Cardone claiming the material is to original spec. and that's why it's in my "if I have to use it" box.

Anyway I really hope you get it running soon, let us know eh!

PS, I just thought of something that happened to me this year. It was running rough and after going through all the possibilities I could think of, it turned out to be a hair line crack in an almost new brass terminal cap, Another new cap fixed the issue. Even a new cap could be cracked. Worth a double check.

 
Last edited by a moderator:
Firing order...

The specialist likely installed the spark plug wires in the wrong sequence, either clockwise, or wrong firing order, or both.

The distributor rotor rotates counterclockwise and the firing order is 1-3-7-2-6-5-4-8. The passenger side cylinder numbering is 1-2-3-4 and the driver side numbering is 5-6-7-8 on left-hand drive vehicles.
My first thought is the firing order as well. I know SA got their version of the Australian Falcons with the Clevelands, but if the 'specialist' is more familiar with Chevy stuff then he might have used the 351 Windsor firing order. 

The other thing is the GM style module in your distributor. I have a GM 4.3 Safari van (1990 with TBI) that I have had to sort out 30 years of neglect after buying it last year. It uses the same style module as the V8s. I was having issues and put in a brand new replacement. Chased my tail awhile before realising the brand new module was bad. There has been lots of discussion about bad ignition components for GMs coming out of China. I would suspect that given the price of that complete set up that they are using some cheaper components. I'm not knocking China, there has been some really good stuff coming out of there, but there is still alot of cheap ready to fail stuff too.

 
Back
Top