Help! Theres a Knocking at my door! Options

[deadjester67]

took the car to the shop a few weeks back had the distributor replaced. then two weeks later my timing belt snaps and i get that taken care of. Two weeks after that my car wont start. that was due to the belts being to tight and a tensioner pully being replaced fixed the problem. but i know have a knock in the motor. any ideas or should i go ahead and get the motor rebuilt?


Heres a link to the video

Celica "Knock"

[Smaay]

a knock typically means a bearing has been eaten up, there is metal debris in your engine, it needs to be pulled cleaned thoroughly, the rod with the spun bearing needs to be replaced, and the crank needs a polish at a minimum. if it tore the crank up too much, i would just replace it.

[Special_Edy]

The first thing I noticed was how rough it is idling. Are you certain the knock isnt being caused by incorrect timing or another misfire issue?
You want to take care of an engine knock asap, the sooner you correct the issue, the less damage and cost of repair you will incur. Drain the oil first and see if there is metal in the oil, a sure sign of bearing failure. It may consist of either chunks of metal in the bottom of the drain pan or more likely a metallic sheen to the oil itself. Next you can remove the oil pan and check the bearing one by one. Id suggest looking at the rod bearings first, they are subjected to greater stress and are more likely to fail. You may be able to wiggle the rod if the clearance is excessive, but otherwise you will need to remove the bearing caps and check visually inspect for damaged bearings or (recommended) use plastigauge. Plastigauge is available at the autoparts store, you need to lay a small piece across the bearing, reinstall the bearing and torque it back to spec, then remove the bearing cap again and check the thickness the pastigauge was compressed to against the chart on the package.
You should also check the main bearings, as long as you remove and install them one at a time the crankshaft will remain in place. Make sure when removing/installing all bearings and caps you remember the order and direction. Usually they are marked 1-5 (mains) 1-4 (rods) with either a stamped number or a corresponding number of dots with a punch. They also have an arrow which should point towards the front of the engine (cylinder 1).

Heres a video of the disassembly of my spun rod bearing.
https://www.youtube.com/watch?v=d7Nyb3_Zy10

This post has been edited by Special_Edy: May 31, 2014 - 9:33 PM