If this isn't allowed, please inform me and I apologize in advance. The only reason that i come here to ask is because you guys are the smartest group of fellows around and I've had olds experience here in the past.

I've got a 1994 dodge 360 that I decided to replace the timing chain on since I was replacing the timing cover gasket. I lined the timing marks up at 12 and 12 with the engine on #1 cylinder TDC and replaced the chain and both gears. Reassembled everything and start the engine and everything was fine it idled normal.

I take it for a test drive and immediately notice the engine shaking upon light throttle so turn around.

I check valves with #1 and #6 on TDC and they both measure the same height and rotor points at #1plug wire when harmonic balancer shows TDC on timing mark. What could I have done wrong?

Additionally it was a cloyes true roller set

 

Did you make sure you lined up the correct marks on the Cloyes gears. It is very to mistake the correct mark with the ones for the advance or retard marks. Or you might just have a bad vacuum leak.

 

I couldve swore I did. It slid right on without much issue. I didnt set it at the advance or retard marks just the factory setting. Im at a loss here.

It ran perfect beforehand so what could have manifested itself during this project?

 

Assuming the gears are lined up correctly, shaking like this sounds like a vacuum leak. What hoses might have been inadvertently disconnected or incorrectly connected?

 

There we no vacuum lines or sensors disconnected during the process. Ive looked long and hard for vacuum leaks and can find none. I do suspect a plenum gasket leak but doubt it would have this much of a dramatic affect on the engine considering it ran fine before.

It shakes in such a manner that an inexperienced person might think a tire was out of round. However, it increases with rpm and will stop while coasting if the gas is let up on.

Ive considered the harmonic balancer might be wrong as it is new with the chain and was ordered online. But id like to perform all adequate tests I can before performing unnecessary work and potentially causing myself more problems.

Ive tried adjusting timing via the distributor against my own judgement as suggested by others to no avail. It gets worse either advancing or retarding the timing.

 

I'm sure you didn't INTENTIONALLY disconnect anything...

Put a vacuum gauge on the engine at idle and see what it reads.

 

Does the shaking go away on heavy accel. If so disconnect the egr valve vacuum line and see if it goes away on light accel. Also double check your plug wire routing and connections. Look for any arcing around the spark plug boots. You can do this with a squirt bottle of water, squirt water onto the plug boots and see if it arcs or misfires. You can also do this with a screw driver and a jumper wire. Use a screw driver with a good handle. Connect the ground wire to the block and the screw driver shank then probe around the plug boots looking for arcing. Kind of a poor mans scope. Getting back to the egr. If the shaking goes away you may have a problem with egr flow. Im not a doge expert but when i worked at Ford some of the engines had egr orafices in the lower intake runners that would plug up and force all the egr flow to one cylinder. This would cause a lean misfire at cruise and light accel when the egr operates. I dont know if that is how this engine is set up but its worth a look. I dont know how far you had this thing apart but sometimes when you tear into older engines you upset the delicate balance of decay and other problems crop up.

 

I will test egr and get back with you.

Spark plug wires are new from Napa as well as new spark plugs prior to timing chain replacement.

IAC valve has a high pitched whistle that changes when I put presser on the sensor so im going to change that out today with little hope for success.

I will throw a vac gauge on there and get back with the numbers and may run a compression check as well to verify valves are opening and closing properly which I believe would rule out timing

 

Check to see if your engine uses an internal or extrenal balanced damper and see what you replaced the original with. Just a few minutes of checking could go a long way. Also check for proper firing order and Ohm out the plug wires.

 

Shouldn't the timing marks be at 6 o'clock and 12 o'clock."?

 

A quick search online leads me to believe ive got the wrong balancer. My engine was made 05/93 and i thought I would need parts for that year. However, it looks like rock auto lists a different balancer for 93/94 and I believe the 94 is the balancer I need.

It just threw me off because the only balancer I can find for 94 on rock auto shows the balancer and pulley being a single unit and mine is separate like it lists for 93. At autozone they list a separated balancer and pulley for 94 that differs from the rock auto part.

Boy what have I gotten myself into...

Will update after ive done the swap and rechecked all that you guys have mentioned. Thanks a million

 

It was the wrong harmonic balancer guys! She runs perfect now under all conditions! Thank you all so much for your help!

Heres a picture as a reward

A few months ago while it was still nice out

 

You are welcome.