2001 Sonata 2.4L Timing Belt Issue

Good afternoon everyone,

115,750 Miles - I purchased the car used. Timing belt looks good...definately replaced not to long ago...Car was running fine.

Tuesday - Car running fine (warm day....78 degrees)

Wednesday - Start car (cold day....40 degrees) ....barely running.....sounds like a loose rocker arm.

Thursday - Start car as I try to diagnose the problem. Boom...before the car turns over to start the engine kicks back. (This is where the sick feeling forms in the pit of the stomach.)

Start taking things apart. Get timing belt covers off...in the bottom...laying on the belt (headed into the crankshaft pulley) are pieces of plastic. These fell onto the belt, causing it to jump a few teeth...I've looked (what feels like) everywhere. Timing belt covers both completely intact. I swear a few of these pieces are squared off (ie. a corner).....so I don't think they were pulley covers. maybe they are?

Questions:

  1. Any ideas on the plastic parts? (They are definitely not from the timing belt covers.)
  2. There are green (paint?) marks on the camshaft and oil pump pulleys. Are these timing marks? I though the little divots were for timing. (I really appreciate hmaservice.com, but does anyone know of a good aftermarket manual with actual pictures instead of diagrams? online or other) - (any ideas where these green marks came from? Sorry about the quality, but here is a picture.
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    - )3. I was planning on resetting the timing and measuring the compression as I turn the engine by hand...make sense? Any ideas? Thanks in advance, Jared

P.S. Sorry if this post wasn't put together in the best fashion. I am really tired...it has been a long few days.

Reply to
Jared
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Your picture didn't come up for me. I'll try again on a different computer. Right now, I've got no idea what the plastic pieces would be unless they're part of the crank sensor. If the sensor plate were hitting the sensor, that would explain the noise you heard.

You won't be able to check compression very well when turning by hand. I'd turn the crankshaft two revolutions to be sure everything clears and then do a compression test using the starter motor.

Reply to
hyundaitech

Okay. Picture came up this time.

On the upper left sprocket (rear balance shaft), the white paint mark is over a depression in the sprocket. This should be aligned with the cut-out in the oil pump casing to the left of the sprocket.

On the crankshaft, look at the cutout in the plate. This aligns with a pointer on the oil pump case. I cannot see the pointer in your picture.

On the lower right sprocket (oil pump/front balance shaft), the dimple in the outer circumference aligns with the pointer on the oil pump case at about 10:30. This sprocket, however doesn't turn an integral number of turns with one turn of the crankshaft, so special procedures are necessary to time it correctly. If it's 1/3 of a turn off in either direction, it's probably timed correctly. To time it, turn it a little away from the pointer. If it tends to return, it's timed correctly. If it tends to keep turning, you'll need to rotate it one revolution to time it correctly.

I don't see the plastic pieces in your picture, so still no ideas there.

Reply to
hyundaitech

hyundaitech...thanks for your time and answers

One more question for right now.... (I haven't been outside recently to work on the car...it has been way to cold (I have no garage to work in.)

What should be done in a timing belt change...(if it were your car @ 116,000 miles): Timing Belt Balance Shaft Belt Water Pump

what else? Timing Belt Tensioner? etc?

I would just like to have everything on hand (while it is torn all apart and) in case there isn't any damage.

Thanks in advance, Jared

P.S. unofficially...who makes hyundai belts?

Reply to
Jared

Updated:

hyundaitech...thanks for your time and answers

One more question for right now.... (I haven't been outside recently to work on the car...it has been way to cold (I have no garage to work in.)

What should be done in a timing belt change...(if it were your car @

116,000 miles): Timing Belt Balance Shaft Belt Water Pump

what else? Timing Belt Tensioner? etc?

I would just like to have everything on hand (while it is torn all apart and) in case there isn't any damage.

Thanks in advance, Jared

P.S. unofficially...who makes hyundai belts?

P.S.S. In the daylight I was able to take a few pictures of the broken pieces. There is gasket in the piece of plastic, so maybe it is from the cover.

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Again, thank you for all your help.

Jared

Reply to
Jared

I'd replace the timing belt hydraulic tensioner and be prepared to replace the pulleys. They aren't a frequent failure point (and they make noise to warn you when there is an issue), so I wouldn't recommend you replace them without verifying there's a problem. You'll be interested in three pulleys, one for the balance belt and two for the timing belt.

Reply to
hyundaitech

I'll need to check the first picture elsewhere, but the second definitely looks like it could be a part of the lower cover. There's not a whole lot of room to get the cover in, and there is on piece on the lower cover that sticks out. In this case, it looks like that may be what's broken off. Look at the inside of the lower timing cover and see if it appears that something has broken off.

I believe Hyundai timing belts are currently made by Gates. But if I recall correctly, this has changed a few times since I began working on Hyundais.

Reply to
hyundaitech

Looking at the first picture, it looks like the front portion of the top of the lower cover is missing.

Reply to
hyundaitech

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