The Stovebolt Site Forums The Shop Area Engine Shop Still having trouble with our 216

We've been trying for 6 years to get our restored 1953 3100 216 straightened out. Last weekend, we put a new correct cylinder head and rocker arm assembly on and got it running, however it seems to be misfiring. Here's more:


-Newer carb, all settings have been double checked. Gas filter is new as well.
-Fuel pump is pumping lots of gas to carb
-All points and rotor button are clean and gapped correctly.
-All rocker arm/valve clearances are to spec.
-Timing is correct.
-Coil is working and all wire connections are solid.
-Plugs are good and gapped correctly.
-Plug wires all have good connections
-Full compression on all 6 cylinders


What else is there? Our truck fires right up, but then gets to spitting and sputtering, no power on accell, only idles on 1/2 choke, and is running rich.

We've thrown up our hands because everything we know to do has been checked over and replaced/rechecked 20 times over.


Bad camshaft?
Timing marks wrong?

Also, we were getting gas (a lot; over 6 quarts of gas last oil change!) in our oil pan. I figured it was the seal between the fuel pump and the block, so I put a new gasket on and reattached the pump to the block. Guess what...still getting gas in the oil.
Is there any other way that gas could enter the crankcase?

First, double-check your firing order. Make sure you don't have a couple crossed.
Mine did that for a while, too. Rebuilt the carb, checked everything, found a bent pushrod and fixed that, still didn't run well. I'm embarrassed to say, I found the fuel shut-off valve close under the cab. Did it myself during a previous job and forgot to open it. A small trickle of fuel was getting through, enough to start and run, but no power.
Sometimes it's the silly little things...

You need a new fuel pump. The gas bypasses the gasket which is designed to keep the oil in the engine. Once the diaphragm on the pump is broken there is nothing to keep the gas out of the engine.

Ok, looks like a fuel pump is on order..



Where is the fuel shutoff valve? I didnt know our trucks had them. Also, we just installed new pushrods and were VERY careful not to overtighten and bend them again.

On my 53 there was a shut-off valve under the cab where the fuel line comes out. If original it may be stuck in whatever position it is in.

What did you mean by a "newer carb"? You should be using a carb meant for a 216.

Did some of your pushrods bend before? That doesn't happen from over tightening them

It was running rough when we discovered we had a cracked cylinder head a while back. Tore it down, and also found bent pushrods. We ordered the correct ones brand new and dropped them in last weekend.

"Newer" carb....meaning a Rochester that was remanufactured and ordered from Jim Carter about 5 years ago. Doesnt have many miles on it. It's newly remanuf and it's the correct 1 barrel for our motor.

I received a tip on the needle in the carburator may be sticking since it has been sitting for 3 years. I'm going to pull the top of the carb off and see if the needle is stuck or if it's turning freely.

Also, we've never really been able to locate our timing mark on the flywheel. I think I"m going to pull the sparkplugs, turn the motor by hand until I find my mark, and clean it up until I can see it with the timing light.

Did you check that the vacuum advance was working? Do you have a good vacuum reading?

Sometimes it is easier to take the clutch inspection plate off and find the timing mark that way. Good luck.

Once you find it paint the timing mark (pointer and little ball) with a little artist paint brush and some white paint.

It will make it impossible to miss when timing the engine.

I know this may sound stupid but many years ago my wife took her car in for a quick tuneup. Everything was running fine but we were planning a trip. I got a phone call saying the mechanic told her we needed a valve job really bad and that the car was running really bad. It was blowing gas out the tail pipe and as they continued to troubleshootthey found gas in the oil.

They change several things including EGR valve and fuel pump. When I got there I asked them to pull the plugs they had installed and install another set. When they pulled the plugs i found the gap was too close and they gap the plugs and everything worked fine.

I know it's a simple thing but just sounded like the same thing that happen to me and its pretty easy to make simple mistakes.

Good luick....

2 Things
1. Turn motor by hand and make sure bell housing pointer is pointing at steel ball on flywheel (it will appear after the triangle mark) at that point make sure the distributor rotor is pointed at #1 AND the #1 valves are closed (up all the way). Make sure the points are just barely open and on top of lobe of distributor.
2. Make sure vacuum hose from manifold to wipers is intact

good luck

Vacuum hose from manifold to wipers is fine, we checked it really well. I will double check spark plug gaps when I can. (truck is 70 miles away). Also, we checked with feeler gauge, distances between the rotor button and contact and the gap on the points.

Also, I suspect the spark advance....but this shouldnt cause a rough idle/misfire/running rich should it??

I had a car do this once. As long as you are absolutely sure the timing is correct, the slightest bid of crud in needle/seat will cause all kinds of hate and discontent. I changed carb and it is fine. If there was no filter inline, its almost a guarantee there is crud in there.

We have an inline filter sitting right by the carb, but it is newer and appears clean.
Our truck has been sitting for 3 years...hopefully the needle is stuck and we'll be finished chasing problems...for now.

I had a new fuel system form the tank to the filter and still found crud in the needle valve one day after the first long ride in a while

I would check it anyway. It only takes a few minutes.
Rich

I'll stick a new filter on there when we take the carb apart just for safe measure.

Also...can anyone tell me what the signs are of a worn camshaft and crankshaft?