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Oct 2, 2013 - I recently had new fan belts installed after hearing a high-pitched, ... Do you hear the noise when the engine is running and the vehicle ... Just replaced water pump (and timing belt) yesterday and squeal ... When driving it make a noise but change out and caught speed the noise is coming from driver side.Missing: 1999 plymouth breeze
The water pump can also make the chirping noise. You can place a very long screwdriver or metal rod against the pump & place your ear to the end of it to localize the sound. A stethoscope is very helpful, if possible.
A KNOCKING SOUND IN THE ENGINE IS MOST LIKELY CAUSED BY ONE OF THE FOLLOWING
1. PISTON SLAP: Makes a sharp metallic noise. Idle engine and short out each cylinder plug. The noise will disappear when plug with bad piston is shorted. Noise will also disappear at acceleration. This can be caused by worn or out of round cylinder, or broken piston ring. Correct problem by re-boring cylinder and/or replacing piston.
2. VALVE NOISE: Makes clicking or rattle noise. Caused by excessive wear on valve stem or lifter, out of adjustment, or stuck valve. Correct by adjusting valve clearance, replace worn valve or lifter, regrind cam, replace valve guide and /or valve. A stuck valve can sometimes be loosened by passing oil through the carburetor while engine is running.
3. ROD BEARING KNOCK: Makes sharp metallic noise similar to a piston slap. Detection is opposite of piston slap. Rod knock is not heard at idle. Knock becomes louder as engine speed is increased. Caused by excessive rod bearing clearance. Correct by adjusting rod bearing clearance to .0015 inches by removing shims. May require re-pouring rod bearing.
4. REAR MAIN BEARING KNOCK: Makes dull knocking or thud noise. Detected at speeds between 20 and 50 MPH. Knock will normally decrease or disappear while pulling or decelerating. Noise will be detected the loudest at normal driving speed, when not pulling or decelerating. Correct by adjusting bearing clearance to .001 to .0015 inches. If knock is excessive, crank should be checked for out of roundness. May need to re-pour all main bearings to correct.
5. TIMING GEAR KNOCK: usually the most difficult to diagnose. If gear is loose or badly worn it will knock in all ranges. Run engine slightly above idle speed. Slowly open and close throttle. Knock will continue to be present, but just as engine slows down knock will become a slight rattle. Remove timing pin and reinsert into timing hole on timing gear cover. Press timing pin tightly against timing gear and accelerate slightly above idle. Knock will significantly be reduced or disappear. Correct by replacing both timing gear and crank gear as a matched set. The two gears should have a backlash clearance of .003 to .004. If more than .009 inch backlash, an oversize (.005) timing gear should be installed.
6. WRIST PIN SLAP: This can not be detected by shorting out the cylinder plugs. Rapidly accelerate and decelerate the engine speed. The engine will pass through a certain speed range when the wrist pin will rattle at about the same pitch as a valve tappet noise. This can be corrected by installing a new wrist pin bushing in the rod or new wrist pin f badly worn. Wrist pin should fit the piston and connecting rod with a tight metal to metal fit. The pin can be pushed into the piston and rod with a slight pressure of the hand. Pin to rod clearance is .0003 to .0005 inches.
Could be cam chain rattle. Famous for sloppy chains and inferior tensioners. Starts about 100k and downhill from there. Could try an engine flush as tensioners may be sludged. I have a 4.0L with a rattle at start up but stops after 5 seconds. Chain is shot.
To me, I think I am hearing a dry bearing. However, an old worn out belt can make the same sound! You could take off the belt and try spinning the pulleys to hear which is noisy, or you could use a mechanic's stethoscope to find out. A mechanic's stethoscope is a really long screwdriver or metal rod about 2 or 3 feet long that they put on different parts (put the handle end to your ear) to hear the noise each part is making. If your belt is good, try the alternator bearings. There is also an idler pulley or maybe 2 that could be noisy. Be blessed.
Bearings in Alternator, water pump, power steering pump or even a squeal from Vacuum line, EGR diaphram or similar. Check power steering fluid level.
Now when you replaced the tensioner, did you notice more pulleys that were just "there" and not connected to anything? These are idler pulleys and are helpful in routing the belt. They have bearings too!
The timing chain area also takes in the alternator and water pump. To isolate the source of the noise, use the old mechanics trick.
Place a 3 foot 1/4 inch brass rod against the flap at the opening of your ear and push until it closes. Place the other end of the rod against various engine components and listen. The noisy problem will conduct the noise up the rod to your ear and you can hear quite precisely where the problem is. Much safer than laying your ear all over a running engine.
You can also loosen the fan belt and run the engine without alternator or water pump (briefly) to see how that affects the problem. Chatter on start makes me think of starter and Bendix gear problems. Sounds like a 2 person diagnostic team to me; one to start the car and one to listen and probe.
Don't know if Subaru Forrester has an engine that has valve interference at piston Top Dead Center. If it is and the timing chain breaks, you are looking at major $$ to recover.
this is a guess but the inner tie rod and tie rod end (you have one of each on each side of the truck), wear out and make a loud clunk, mostly when changing direction, but also on starting & stopping. ABout a $200 repair including a front end alignment.
Call at least 3 shops for an estimate including your Ford dealer.