[Gerancos]

Hey friends,

My old 65 mustang (V8 289 with a new holley carb) is in trouble.

It was driving great for a year or so. A few days ago it had trouble starting. When it did start, it had a very rough and uneven idle, and very low power when driving - like it wasn't running on all 8 cylinders, felt like.

When i revved it in idle, it backfired and a lot of black gunk shot out of the exhaust (picture of the gunk on my driveway included).

It then idled OK, but there was A LOT of think white smoke and a strong gas smell - I might have flooded it with all the starting attempts, though.

I pulled a spark plug and it's very black, and oily (picture of the spark plug included).

I took an oil sample, you can see new oil in the shot glass on the left, and my dark-looking oil on the right.

Anyone have any advice on:
1) what could be the cause/problem of this?
2) how to proceed? How to i fix it?

Thanks so much to you all in advance!

 

[Gerancos]

First of all, thanks to all of you for the many and interesting replies! You're great0

I'll answer your questions as best i can:

• as far as I know, the egnine was never rebuilt
• the odometer says 25.000 miles, seller said 125.000 miles. No knowing how many times it really rolled around, though.
• the carb was changed about 1.5 years ago from the original autolite 2100 to a holley 500 cfm street avenger
• I had driven the car quite recenttly, most recently was a week before the issue. 3-hour drive and it drove like a charm
• the oil is abouit a year old. I've driven about 1000 miles since the oil change.
• i don't think the oil smells like gasoline, but i'm terrible at smelling things so not 100 sire

I'm pulling the rest of the spark plugs today to see how they all look individually. New ones have been ordered and are in the mail. I've also got a new set of spark plug wires sitring around, so I will take this opportunity to switch them out as well.

Once the plugs/wires have been replaced, I'm gonna try to start it, just to see what happens.

Basically next actions:

• pull/inspect all plugs
• put in new plugs
• put in new wires
• check float level (there's a little glass window on the side of the holley carb
• If all the spark plugs look equally black/oily, was thinking about making the mixture a bot leaner too

After this i'll try to start her up, see what happens.

I'll post back here with the results, any further advice is greatly appreciated - keep it simple i'm a bit of a hobbyist/noob