Violent Shaking

[matthud]

I was driving my 69 427 yesterday. When I was driving around at about 1500-2000 in 2nd gear the car started to violently shudder back and forth. It happened at a constant speed, the car would slow down then jump forward. It was doing this over and over, it seemed to get worse as the car got warm. Then I had someone else drive it to see if they new what was causing it. Anyone know what this was caused by? Clutch? Misfire? Hesitation?

 

[wishuwerehere82]

Sounds like your carb is still not quite right. Loose mounting bolts or floats not adjusted level. Did you put the baffle back in?

 

[matthud]

You think this is a gas issue? The strang this is, if I took the engine past about 2000, is seemed to go away. I dont have the baffle in just yet, I am afraid to undo my gas line because I just got it to stop leaking, I'm sure when I take it off again to get he baffle back under, the gas will start dripping again. Could it be something else like maybe the clutch slipping?

 

[JohnZ]

If you're talking about the stainless steel baffle in the other thread, don't drive the car until you re-install it (and plug the "hot-slot" holes first); with no baffle, you have hot exhaust gases directly against the bottom of the pot-metal carb castings, and you're boiling the fuel in the float bowl, and the soft-plugs in the bottom of the float bowl can fail from the heat, then you have a fire.

 

[wishuwerehere82]

John's correct as usual. You probably are boiling fuel in the float bowl without the baffle in. Loosen the fuel line with a rag under it to catch the spill. Loosen the gas cap first to relieve pressure in the tank.

 

[matthud]

I checked my timing tonight, seemed way too advanced, so I brought it down a little bit. Also put the baffle back on. Still need to take it back on the road to see if it made any differences. Also found that the clutch spring was missing, so I got a spring on there, to see if the clutch was slipping.