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. http://i13.tinypic.com/2j46pet - )
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.

 

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.

 

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.

 

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?

 

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.

http://i18.tinypic.com/40b34ea.jpg
http://i17.tinypic.com/48whufl.jpg

Again, thank you for all your help.

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.

 

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.

 

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