Valve puff?

[JCD]

My Ford 650 with 172 eng. has a distinct puff occasionally in the exhaust. It sounds like putt,putt, puff. repeat etc. It runs good overall, and has had a recent tune up and valve adjustment. Any thoughts?

 

[daman]

floating?Was valve spring pressures checked? valve

 

[daman]

Why is the darn edit not working?

anyway i meant..

Was valve spring pressures checked? valve floating?

 

[Ed H.-OH]

Hi! My old 35 Ferguson done that for 25 years, I put in electronic ign. and it stopped 90% of it.
Purrs like a kitten now, idles clear down to 400 rpm. I'm not sure but i think it was the points.
Shaft wear makes point gap change,and bad point condition causes inconsistant spark, I assume this is a gas tractor,If not I'm sorry.-ed

 

[Dave Warden]

I also put in electronic ignition and lost a few little quirks. Restoring now. With reworked head and new rings, and 40,000 volt coil can,t wait to feel the differance.

 

[Brian Allen]

JCD
I would guess that you have one valve set a little too tight.
Very easy to do.
Brian

 

[JCD]

Thanks for the replies. No, I don"t know about valves floating or being burned etc. The puff has been there before I adjusted them. The adjustment did quiet a tick I had from a #1 intake at .025. The tractor is in great shape, and since it is a worker, the 12 volt alternator with EI sounds appealing. Worth the money?

 

[Dave in MS]

Worth the money? Imho, Absolutely. Especially so if you are having any charging issues.

 

[Hobo,NC]

.A lean miss at idle that will sound like Pop corn pop’in in the exhaust.

A rich mix will have a pour laboring pup-pup-pup idle in rhythm.

if Adjustments are applying the choke help its probably a carb mix issue.
One reason EI helps eliminate a rich issue is it has a longer available burn time so the spark stays with ya till the fuel is burnt... EI will help recharge the coil faster for the next spark event if all the available energy were used up. EI is just a more efficient switch,,, you may not need it if all the stars in the universe line up just right,,, but if you do it does a better job of turning the coil on and off.... That's not to say EI will not run into a wall and B over weemed by a rich condition. Its just better at recharging the coil and can help burn off the fuel in a slite over-rich condition....

 

[Ed H.-OH]

Hobo, Thanks for the tip, That makes good sense.And i beleave it's correct as a chain saw will do as you described when you are setting the idle mixture to get it to set and idle without loading up.I will check the idle mixture on both tractors in the spring.
I went to EI as good points are getting hard to find. My 2000 ford Quit on me 2 times plowing in a snow storm,I had to pull the cap and drag paper through the points to get it running,and the last time I dropped the litle clip under the rotor in the snow and almost froze before i found it.Needless to say i was not happy. I couldn't find good points local,so i bought the EI and solve the problem. I only put 1 set of points in my ferguson in 25 years, but back then points were common and the stores stocked good ones.Thanks for the wake up-ed