2 part question

Hello it has been almost a week since I posted a question so I have two for the Guru's. Anyone had an issue with having a harmonic balancer without a timing mark on it? What is the best way to set the timing with this problem? 2nd question: The old 258 with the Carter yf hates to start in the cold. I rebuilt the carb, and set everything to spec and replaced the choke spring. I set the spring to one rich (factory spec) but when I step on the gas the choke has like an 1/8 to 1/4 inch opening when cold. Is this correct or is the choke still to far open? What else could be the reason it does not like cold weather? Aside from a choke adjustment, and high speed idle screw, is there another cold starting adjustment. Thanks for the time guys and gals.

 

I don't know about the 258, but usually timing marks are stamped into the damper/pulley. Could yours just be painted over and hard to see? To get the damper marks close to the pointer (you do have a pointer?) pull #1 sparkplug and distributor cap. Turn engine by hand until the #1 piston is at top dead center and the rotor is pointing to the #1 sparkplug wire location. Most distributors have a mark indicating #1 location. That should be 0 deg. TDC You can use a pencil stuck in the sparkplug hole to see when the piston is at the top of it's stroke.

 

Stone cold your choke butterfly should be completely closed. Just check to make sure that it opens all the way when at operating temp.

 

Re the YF, when cold, the choke flap should open some at WOT (wide open throttle). Usually you need a pump shot (pump the pedal onece or twice) in addition to the choke in order to get the engine started.

You can adjust the float level, float drop, metering rod, initial choke valve clearance, fast idle setting, choke plate, idle speed, and idle mixture. All of these are covered in your TSM. If it won't stay running when cold, I'd first bump up the fast idle some. Then I'd richen the idle mixture a little.

 

I made all the adjustments when I rebuilt it. I also measured all the clearances and everything was right on the money. I thought that maybe I would bend the fast idle linkage a little bit and maybe I could get the choke plate to close some more. I think I was having an issue, and I have to confirm this, that setting the choke to rich was inhibiting the fast idle from kicking down. So I am in a quandry. I set it lean enough that it kicks down, it does not start in the cold weather. Rich enough so that it starts and it does not kick down. Any other ideas??

 

You have an EGR valve? it's supposed to be fully closed at cold idle. If there's a lot of crud (carbon) on the pintle, it can hold the valve open and leak exhaust into the intake when it should be closed. This can cause a rough idle, and I'd expect that the problem would be a lot worse when cold.

 

To tell you the truth the idle is not all that rough at any point high or curb. It never stalls and the idle is pretty smooth. My main issue is starting and getting it to go from high idle to curb idle. When it kicks down finally to curb idle it is very smooth at 600 RPM's.

 

I think I may have an ignition problem which is inducing the hard starting. I am looking into this this weekend.

Has anyone dealt with the lack of a timing mark on the pully? I have never seen a pully without a timing mark. How do I se the timing??

 

It sounds like you need to richen the choke slightly and possibly lower your fast idle a bit. Make the adjustments while it is cold.

I recommend richening it just to where the choke flap closes. Ensure there is very little tension on the choke spring when fully closed. This will restrict the air at startup and then immediately after startup the choke pull-off kicks in and pulls the flap open to an adjustable 1/8 - 1/4".