39 deluxe not running right
 

I have a completely rebuilt stock engine, rebuilt carb.,new points, plugs, condenser, in line fuel filter and plug wires. It ran good for 100 miles after rebuild but now it backfires upon rapid acceleration. Any suggestions on what to do would be appreciated. My next move will be to check points setting and timing. HELP!!! Jon Laing

Re: 39 deluxe not running right
 

change condenser first

Re: 39 deluxe not running right
 

Or coil

Re: 39 deluxe not running right
 

AS I understand it the car would not run at all if the coil was bad and the condenser is new. Am I missing something? I will next check the point settings and tightness of the condenser wire. Anyone have any other thoughts? Jon L.

Re: 39 deluxe not running right
 

If it backfires through the Carb. it is a sign one or more of the intake valves is not closed properly. Have you considered using some MMO in the motor oil, or the fuel. The Holley 94 Carb is very sensitive to backfire that can rupture the power valve. This will cause very hard re-starting due to flooding, excessive crank time before cold starts, rough idle, poor acceleration.

Re: 39 deluxe not running right
 

The backfire is out the exhaust. It starts very good with little turn over. The carb. was just completely rebuilt. Jon Laing

Re: 39 deluxe not running right
 

That is not true, the car can start and run fine with a bad coil. Then it will start to act up as the coil gets hot. Once the coil sits for a while and cools down it will appear to be fine again. The same thing can happen with the condenser, fine when cool, not fine when hot. If you read some of the past postings, even a lot of new condensers can cause a problem.

Re: 39 deluxe not running right
 

@jon laing
JSEERY is just like E F Hutton, "When he speaks, people listen!"

Re: 39 deluxe not running right
 

That's just conveying info from the experts, like Bubbas, Charlie, etc!

Re: 39 deluxe not running right
 

And just to, I guess add credence to JSEERY which doesn't have to be done, Especially new condensers, doesn't necessarily mean they are good and as JSEERY said, we have experienced the "Coil Phenomena" many times throughout the years (and condenser too) to the point of "baldness". Even after repair and the car sitting for two months, condensers can go bad.

Re: 39 deluxe not running right
 

In my "travel kit" I keep a known good condenser with 16" leads with alligator clips on the ends so if on the road it starts to act up like that I can temporarily clip this on the distributor to get home. If you had one like this you could eliminate the condenser as the problem if it didn't help and would point the finger at the coil. It will run fine with both bad and good condensers hooked up, the bad one won't prevent the good one from doing its job.

Re: 39 deluxe not running right
 

Thanks for the advice. I will double check the coil and condenser and let you know the results. Jon L.

Re: 39 deluxe not running right
 

All she needed was adjustment of the distributor vacuum brake. Jon Laing

Re: 39 deluxe not running right
 

Glad you got it figured out

Re: 39 deluxe not running right
 

Picked up the 39 yesterday. Mechanic adjusted the distributor vacuum brake adjuster and it solved the backfire problem when accelerating; however it still misses when I accelerate. Perhaps I should replace the vacuum brake plunger, spring and adjuster. Anyone have any suggestions on what to do next? HELP & THANKS. Jon L.

Re: 39 deluxe not running right
 

Hi there, Your distributer contacts could have closed up in that 100 miles. Recheck the contacts. They must meet up nice and square to each other. Do some bending with a pair of sidecutters if need be. Many of the current crop of new contact sets are badly made and don't fit like the originals. Contact faces nice and clean shiny metal. Set contacts (both) at .015" and a little smear of high temp bearing grease on the cam. You need to be very fussy on how well you do this job. If you now know that the contacts are correct then you can move on to other things if the trouble is still there. To test condensers you really need a good automotive condenser tester that tests capacity, leakage and series resistance. I have had brand new condensers that were faulty and old ones that were faulty. Correct capacity for early Ford V8 condensers is .36 mfd. As a starting point on the vacuum brake adjustment leave 3 threads showing between the lock nut and the underside of the adjuster bolt head. Regards, Kevin.