The Stovebolt Site Forums The Shop Area Engine Shop Where's the fire?

I've got an "It ran BEFORE I took it apart" dilema. For some reason, I've got no fire on #1 and possibly #2 cyl. I've got a 235 low pres. oiler, before I tore it down I went through the carb., put in new plugs, wires, points, cond., cap, rotor, fuel pump, and the thing ran so smooth and idled so nice, it was unbelievable.

Now after tearing down, cleaning, honing, re-ringing, checking bearing clearences, painting, re-gasketing, and re-assembling, it runs rougher than a cob, and won't idle. It seems as though there is no difference when I remove #1 and #2 plug wires while it's running. I've re-re-re-checked valve lash, switched plugs and wires around to different cylinders, re-gapped points, re-checked dist. placement on TDC, and still no change. It is a little better at a higher RPM, but still not good. I'd like to reassemble the front clip, but not until all motor work is done.

Any ideas? Thanks 'Bolters!

HOT DANG!!! In my morning caffine induced brainstorm, I got to thinking, "What else could make a motor run so rough?" How about a vacuum leak. Followed all lines from carb., no leaks. Next, "What do #1 & #2 cyl. have in common?" AH HA, they receive their fuel from the same intake port, as do #3/#4, and #5/#6. Upon further inspection, I could see a very small gap between the intake/exhaust gasket and the head at the #1/#2 intake port. It looks as though the intake manifold had been welded at some point at that port. I loosened the manifold bolts, and persuaded it with a dead blow mallet and began tightening the bolts back and forth. Hammer, tighten, hammer, tighten until there were no gaps any where. FIRED RIGHT UP! Evidently the manifold had warped from the heat and just needed help to get the alignment sleeve to seat in the head. I'll let the motor get warm, and then I'll re-tighten bolts again, and hopefully all will be well with the world.

Glad you got it figured out. Thanks for posting the solution. Making sure those rings are in place should be on the check-list for reassembly.

Keith,
Thank you for letting us know what was going on. I've been relying on a lot of these threads to build myself a troubleshooting guide.

(Peggy - they would make a great book . . .)
- K

Pakrat47 - wow - good thinkin'... that is something good to know.

My dad has a '53 with a '57 235...

-W

if it isnt a vacuum leak check the head gasket between #1-#2 cylinders.i have had them to pop the gasket and when they do niether cylinder will fire correctly.

I had a bad miss at idle and found an intake manifold gasket leak by accident. I was spraying carb cleaner at the carb base gasket and missed it. When it hit the manifold the engine miss disappeared and the engine sped up. I repeated it several times, then pulled the manifold, replaced the gasket, and all was fine.

If you do end up pulling the manifold, it's a good idea to run it down to your friendly local machine shop and have it resurfaced. For a couple bucks, you get a nice, fresh surface for that gasket to bolt up to-- plus, if it is a little warped, you've taken care of that, too; and hopefully, prevented a possible recurrence.

ya but if you do that grind your alinment rings down to so the arent to wide