The Stovebolt Site Forums The Shop Area General Truck Talk Help! 235 Engine running trouble

Please help. I swapped out my 216 for a rebuilt 235 for my 1953 Chevy 3100. I may have mixed up the carbs as the 235 is running so rich that it is fouling and blowing black smoke. I checked the main jets and the one in the carb online is a #57 the one on my bench is a #52....Otherwise the carbs look the same. I assumed tht the 235 would have the larger jet so thought the right one was put in. Not even sure if this is the problem or something else (Also are there other diferences in the 2 carbs forthese engines...? They look the same other than the main jet........Any suggestions would be greatly appreciated!!...Thanks, Sammy

I'd be inclined to look for a float level problem.
Float hanging up on something.
Float leaking.
Bad needle/seat.

Sammy,
I think the Rottenchester has a powervalve. Maybe it's stuck open!


Stuart.

Did you put the spacer back between the carb and manifold? The vacuum passage that runs the powervalve goes through the base and needs a notch to uncover it so the power valve works.

on mine the base of the carb is slightly largere on the 235 216 carb wouldn't fit over the studs. found out by buying NOS 216 carb $125 wasted after my misguided modifications

Hi; As i understand it, the power valve is open until vacuum closes it. When the throttle plate opens during acceleration, the vacuum drops and the valve opens. So when the throttle is closed (at idle) the vacuum holds the valve closed. Therefore, a vacuum leak might cause the problem. Don't know, just a thought.
Rich

Had a similar problem and it was the vacume intake at the base of the carb. Make sure the gasket and heat spacer do not block or restrick the intake hole.

My 216 had a Carter YF carb on it that was all jacked up.. I just yanked the Carter WB carb off the 235 in my 2 ton and slapped it on and it ran fine.. it was a direct bolt on swap with no adjustment required.

I'd double check that the carb is seated properly, and make sure your timing is on and that the vac advance is working properly.

I've got a question, and it's a little off this topic. I have a 1965 GMC Panel with a 305E V6. It had been sitting in the brush for a few years now and I'm trying to get it running. I've already done a lot of work to it and only one thing stands in my way now. The starter. It was rebuilt along with the soliniod but whenever I try to turn the truck over, it makes a grinding noise. I'm pretty sure it's caused by the ringear grinding against the flywheel. I was told that you can just take a large wrench and manually turn the engine over (if I found the thing to "wrench"). Doing that might make the gears line up. There are two bolts holding the starter in place and the lower one is completly sinched down but the upper one is little more than hand tightened. Anyway, if anyone has any suggestions that can assist me, I'd appperciate it.

-Julian

Julian C,


I don't think I would waste time on the ring gear which is actually mechanically attached TO the flywheel...focus on the starter. I would think something wasn't done properly in its repair. The flywheel is dumb, it just waits for the smart starter drive gear to come out and do it's thing. The solenoid is what makes this happen.


Stuart.

Julian,

Can you grab ahold of the fan and turn the engine over by hand?

One thing I learned with my last engine "wake up" experience is that just because a motor isnt absolutley stuck, it dosen't mean that it isn't slightly stuck.

I'd take the starter off all together, and hook it to a battery and see if she spins. If the starter spins free and fast, then the starter is probably fine.

Pull all the plugs and dump some penetrating oil down the cylinders and let it soak for a couple days. I usually just spray WD40 down there, but I hear that PB Blaster or Kerosene works even faster.

With the plugs out, and the transmission in neutral, you outta be able to turn the engine over by the fan with great ease.. don't even bother trying to start the engine till you get to that point.

Julian - Also make sure you have excellent quality power and ground connections to the solenoid and a good battery with clean connections and solid cables.

Sammy,

Your thread was hijacked..take it back! Are you up and running? :o


Stuart.

The 52 is too lean for a 235. They generally have about a 55 but the 57 would not cause any problem. Check the float level & make shure the float does not have gas in it. Check the power valve it should go up & down & unseat the ball in the power jet. Check make shure there is a pasage for vacuum to get to the hole in the bottom of the carb.