Topic: 351c 4v running problem

[bfsniff]

   Its completely rebuilt iv ran it for probably a total of 1 hour.  We have the timing right on TDC,  firing order 13726548.  new plugs and wires twice.  It runs and idels but is ,missing on 2 or 3 cylinders.  You pull the plugs off on those and the engine smooths out,  very weird A? Iv been working on this for about a week and having a machanic help me.  Need some more ideas!

 

[Soaring]

Just make sure you have the wires hooked up to the distributor correctly.  #1 cylinder is about 1:00 o'clock on the distributor cap.  Then go counter-clockwise from there to #3 then left again to #7 etc. etc....Then set your timing to between 6 and 8 degrees BTDC.

[bfsniff]

i have checked that many times

[bfsniff]

should i try another firiing order? it seems like its  the FO problem. the 302 360 FO.

[66GTKFB]

Are you sure it's a 351 Cleveland? It's almost as if you had a Windsor cam installed. I don't know if the two different timed cams can be interchanged but who knows.
Jim

[Soaring]

The 289/302 FO is 15426378, so that is so far removed from the 351 FO that if you have it running, you must have a 351, and the FO is not your problem.  On the plugs that are not firing, have you removed the wire and grounded it to the block while the engine is running?  Did you get a blue spark when you did?  Just make sure you are getting spark from those suspected wires.  If not, then replace the wires.  If so, then take out the spark plug and see if you are getting an arc across the tip.  If not, then the plug itself is suspicious. 

[bfsniff]

im getting great spark from all plugs, and i have a RV cam for a cleveland in it.

[bfsniff]

its # 2 and 7 cylinders that are dead when you pull the plugs the engine runs better.  we were working on it tonight and think it might be a bad cam  we checked everything else. good compresion, spark, gas.   Do you guys think a cam could cause that?
I would suspicion the distributor before I would think about the cam.  Do you have an MSD or Pertronix?  Since it is a fresh overhaul. have you checked your tappets (rockers) to make sure they are adjusted correctly?  They may not be allowing enough gas into the firing chamber.  That would be the intake valve.  Do you know how to adjust your tappets/rockers/valves?  See if the tip of the spark plug is wet or dry on the #2 and #7.  If it is wet, then you are getting gas in there, but if dry and still not firing, you may need some adjustment on the valves. 

[Soaring]

Adjust your valves.  You may not be getting sufficient fuel to #2 and 7 to fire. 

[bfsniff]

they are non ajustable rockers.  i just found out that number 8 cylinder has 0 compession the rest have good compression. the head gasket isnt leaking either,  has to be that the cam is opening the vaulve at the wrong time or the timing chain slipped right?

[Soaring]

That would be my guess now that you have narrowed it down to either the cam or the slipped chain, however, if the chain slipped, you would have a rough running engine on all cylinders.

[jethat]

Sounds like the cam didnt make it through the break in. Thats happining more these days because of the changes in oil. the removed the zddp that the cams really liked.

[Soaring]

What is Zddp Jethat? 

[jethat]

Zinc dithiophosphates
http://en.wikipedia.org/wiki/ZDDP

[Soaring]

Yeah, I knew they removed the zinc, but I didn't know the full name.
Thanks.