Does anyone the ignition timing for my Ford F250 4x4 with one barrel YF4 carb 300-6 engine? I have a (worthless) chilton book and it says "see underhood sticker", Yeh, right. I looked at the codes and tuneup page and couldnt find what I needed. I have it set at 10 degrees but she pings like crazy when it gets hot and pulling a hill. I will be hauling a boat on lots of hills soon and it will be hot, I'm sure. Thanks in advance, no pun intended.

Jeff

 

This is from my site.

For 1978 trucks.


First get your calibration code then scroll to the bottom > match the code and get the specs.

http://www.clubfte.com/users/mil1ion...e-upSpecs.html

 

Thanks, Dennis. I looked under 7-78-R10 as the chart says for my 77 F250 manual, non calif., it says 10 degrees btdc. I have it adjusted for 10 and it pings when warmed up. I disconnected the distributer vac hose and plug it when I do the adjustment, just like the book says. Any ideas? Does this thing just need a higher octane fuel? Or should I just set it for 6 degrees?

Jeff

 

Jeff, there's several things you can try. First, like you said, drop the initial timing down to about 6-8*, and see how it runs. You can also reduce the sensitivity of the vacuum advance. Use a 1/8" allen wrench and turn the adjustment screw in a couple turns. (Remove the vacuum hose to the cannister, and insert the allen wrench in the port.)

Installing heavier distributor advance springs will bring the total advance in at a higher rpm, and reduce pinging.

If none of this works, you can go up a couple sizes on the carb main jet(s). This will enrichen the mixture, hopefully enough to prevent the pinging. You can get jets from 'holleypartsforsale.com'.

 

You may have a worn distributor also. Get a rebuilt distributor installed. If you still have a part throttle ping you may have to adjust your vacuum advance. This most offen occurs due to a defective or missing EGR valve.

 

Hi Guys,
Well, I adjusted the timing to 6 degrees, It seems to run hotter and diesels when I turn it off. Also, it has a sound from the exhaust that sounds like a leak. When I play with the timing and retard it a lot, it makes that sould, not sure why. I don't think the distributer is worn because it seems to hold the setting. Loneranger, where is this canister? I dont think I have one. Just a vac line from distributer to carb. Any way to still adjust sensitivity? By the way, where is the egr valve, may not have one of those either! Thanks again,

Jeff

 

Jeff, the cannister I referred to is the vacuum advance itself. Just remove the hose, and insert the 1/8" allen (hex) wrench into the hole where the hose was. You should be able to feel when it indexes into the screw. Then turn the screw to adjust. I'm not absolutely sure yours is adjustable, but I have yet to see a Ford vacuum advance that wasn't......