Extreme Engine Vibration 2.4L

So a new (pulled from wrecked car) engine was put into the car due to a radiator hose blowing and my daughter continuing to drive and overheated the original engine.

Due to the fact that the dual mass flywheel was $600 alone we opted to put a solid flywheel conversion kit designed for the car along with a brand new clutch pack.

The work was all done by a mechanic in my home town.

There is an extreme vibration between just above idle and about 2000 RPM. It is very loud inside and shakes the entire dash, like a very loud HUMMMM.

The mechanic checked the motor mounts and they appear fine. He checked the harmonic balancer which seems fine as well. What else could be causing this problem. I can understand that the dual mass flywheel is designed to smooth out the engine but this vibration is extreme.



Hope these work and hope they help!!!

I feel like the classic “long time listener… first time caller”

Thanks in advance!

I take it that this is an externally balanced engine? There didn’t happen to be a trilling template included with the flywheel, was there?

The reason I ask is that the flywheel may fit both internally and externally balanced engines (half the part numbers). When the engine is internally balanced the installer leaves the flywheel unchanged. If the engine is externally balanced the installer needs to have material removed (in the form of drilled holes to a given depth) at certain points.

This engine has a balance shaft driven by the timing belt. It the timing belt was recently replaced on the engine and the balance shaft was off a tooth or two, it will cause an engine vibration.

I have that car with the dual mass flywheel. They are meant to smooth out drive-line vibrations, but I didn’t think the vibrations from a solid flywheel were as severe as you’re seeing.

Geeaea raises some interesting questions, that you should understand.

I contacted the place I got the flywheel and clutch pack from and asked about the possibility of needing to drill the flywheel and they said that it could possibly be if the flywheel was not torqued down properly or in the correct pattern. I do not believe that the timing belt was messed with at all before this engine was put it.

I have not been able to figure out through my research online if this engine is internally or externally balanced.
Thanks for the help thus far… any additional help would be greatly appreciated.

The word “new” should never be used when discussing a “used” engine and maybe this vibration is not flywheel induced at all.

The first thing I would have done before installing this “new” engine would be to run a compression test on it BEFORE the installation.
If this engine has a cylinder down then nothing in the world short of major engine repair will solve this problem.

Weird things can happen to cars and their engines when they get into wrecks…Shock waves…if that engine has a balance shaft, it should run smooth as butter. I think you are looking in the wrong place with the flywheel…What’s wrong with the flywheel on your old engine??

I’m betting, for whatever reason, the balance shaft is NOT correctly indexed…

Four cylinder engines are inherently perfectly balanced. Two pistons moving up while two are moving down…But when you try for 2.4L out of a four cylinder engine, the reciprocating mass gets so large they start to buzz pretty good hence the balance shaft. If that shaft is “out of phase” the engine will REALLY buzz…

Point taken!

I just thought that since I explained it was pulled from a wrecked car readers would understand that it is a new to the car or new to me engine.

Like I said point taken.

The point you speak of with this compression test is exactly what should have happened. The mechanic got the engine in the car then it wouldn’t start. Ended up doing a compression test and no compression. The valves we somehow messed up, so then the place he got the engine from got a hold of the car and did work on the head from what I know. Now the car is running but has this terrible vibration. It has been a complete nightmare dealing with this car.

Kia doesn’t offer long blocks only short blocks that are about 1200 alone. then you get heads that are about 800 and it has no valves or cam shafts. it is ridiculous. Several junkyards don’t even bother reselling these engines because they get them back too often with no compression problems. Ever heard of these kinds of problems.

The old flywheel was very worn. so it needed to be replaced.

No compression and the valves comment points towards a broken timing belt or an engine in which the valve timing is seriously off. This leads to bent valves and nicked pistons.

The hidden issue is that if the engine has suffered a broken timing belt, etc. and suffered bent valves what can happen is that a connecting rod (or more than one) may bend from the valve/piston impact. This can cause an engine vibration and there is no cure short of a complete, and very expensive, overhaul.

What I would do is this.
Run a compression test again.
Use a dial indicator and probe and measure piston travel in each cylinder. (Should have been done while the head was off) The travel should be the same in all cylinders. If not, a rod(s) is bent.

At this point I would think the vibration is either a compression issue or a bent rod issue; both are major headaches.

The issue I have heard of multiple times with these engines is if they sit lets say in a junked car things go bad valves end up getting stuck which would result in no compression to my understanding. I have never heard of this happening before the issues with this car. Does that make any sense of have yall heard of anything like that before.

Can the measurement of piston travel be done with the head on … like through the spark plug hole?

Again I really appreciate all the help on this issue. This has been an ongoing battle since mid March.