Timing Belt Oops. Won't start.

[envisionelec]

2004 MDX Timing Belt replacement.

First mistake:

I did NOT check TDC because I didn't know how. (durrr) Of course, the front cam had moved, but I had paint marked them and the belt before removing it: I put the belt on the bench and very carefully paint marked the new belt (correct side facing up, tooth by tooth). I installed the belt after having a helper push the cams back into position with all marks lined up.

The car does not start...clearly struggling against some compression (re-re-regaahh). I tried that ONCE. It didn't jam up, so I think I'm clear...

I need to know the steps to getting the cams and the crank set to their correct TDC positions. As I understand it's 2:1 Crank:Cam. But I need to know what I need to move "first" so I don't clatter a valve into a piston.

Thank you!

[TexasHonda]

Before doing anything else, I would suggest purchasing a download manual from automanualsource.com (OEM manual). This will show how to align crankshaft and camshafts w/ illustrations. Hopefully you are not too far off and can recover by aligning camshafts and turning crankshaft slightly.

If alignment is very far off, you have likely already damaged some valves and will have to pull the head/s for valve repairs

I managed to realign a 5-cylinder Acura TL engine that had lost timing (crankshaft pulley came off, don't ask how, it's a long sad story). I removed spark plugs, aligned camshaft, and turned crankshaft towards alignment slowly. Whenever I felt resistance of valves, I turned camshaft slightly to relieve resistance and proceeded. I got it realigned, but of course damage was already done during loss of timing and head had to be repaired. I'm not optimistic for your case.

good luck

good luck

[envisionelec]

Originally Posted by TexasHonda

Before doing anything else, I would suggest purchasing a download manual from automanualsource.com (OEM manual). This will show how to align crankshaft and camshafts w/ illustrations. Hopefully you are not too far off and can recover by aligning camshafts and turning crankshaft slightly.

If alignment is very far off, you have likely already damaged some valves and will have to pull the head/s for valve repairs

I managed to realign a 5-cylinder Acura TL engine that had lost timing (crankshaft pulley came off, don't ask how, it's a long sad story). I removed spark plugs, aligned camshaft, and turned crankshaft towards alignment slowly. Whenever I felt resistance of valves, I turned camshaft slightly to relieve resistance and proceeded. I got it realigned, but of course damage was already done during loss of timing and head had to be repaired. I'm not optimistic for your case.

good luck

good luck

Nice. My wife is going to kill me. I learned I could have had it done for $350. I was quoted $1100 at the dealer. Now I'm really upset.

I have the FSM...can't find it...went ahead and bought the online version. Gotta wait a couple hours to DL it? WTF!

I don't understand how all my marks could line up and it won't start. Could just being off ONE TOOTH cause a no-start condition?

[lion9mdx]

$350 is unusually low. Normally the prices discussed around here might start in the $600 or $700 range.

[envisionelec]

It's what I read about a local Honda/Acura only repair shop. Who knows...

I'm not a mechanic...just a second had owner of an MDX. I am about 95% on success of repairs, even more difficult ones. I remain hopeful but willing to accept that I might have screwed it up.

I'll be looking at it tonight. How can I tell if I bent a valve? It should run, but maybe sound like crap?

[TWOxMDX]

See the PDF file in the second post of this thread, it shows the proper timing alignment:

Camshaft Found Misaligned during Timing Belt Change

From experience; don't grab the camshaft pulleys with your hands, it will jump and potentially cut your hands (don't ask how I know!).

[envisionelec]

I went back to the car tonight and performed the following.

1. Rotate crank (with belt installed) through 360 degrees with a standard 3/8" ratchet. I was met with a couple "springy" points, but if I backed off them I was able to push through with little resistance. At that point, I knew I had no damage.

2. Continue to rotate crank another 360 degrees to its mark. I knew I hadn't moved anything more than 10 degrees so logically the cams would not be 180 degrees off.

3. Remove the timing belt from the cams. The front cam did not move, but the rear cam (exhaust?) was springy and jumped CW about 60 degrees. From what I'd read on some threads, this was correct.

4. Locate front cam back to its timing mark. I actually pushed it further in both directions to feel that hard stop - it's a much different feel than the spring which has a progressively harder push to its apex then a quick release. Hitting the valve feels like hitting a wall...you'll know it.

5. Locate and hold rear cam to its timing mark. It was a little more touchy to center as it was at the top of a spring load. But there was a broader apex than the front cam so it was easier to hold in place.

6. Reinstall the timing belt according to the directions.

7. I was three teeth off on the front cam and 5 teeth off on the rear, both CW of TDC.

I'm now an expert having fully assembled and disassembled the components three times in as many days. I found two galled bolts in the engine mount which I chased down with a tap. I suspect an earlier repair/dealer did that. The bolts are Grade 10, M10x40 1.25mm pitch.

Note that the AutoManualSource download password didn't show up in time for me to reference it. I also couldn't find my FSM. So I winged it. And frankly it was a piece of cake by "feel". Sometimes book knowledge can hold you back.

The truck started normally and ran fine, sounding exactly as it did before.

[phins2rt]

Good news!! I removed my spark plugs (and maybe you did too) to lessen the resistance when turning the crank 360 degrees. And I was replacing them anyway. Glad to hear everything is a ok!!

[envisionelec]

Originally Posted by phins2rt

Good news!! I removed my spark plugs (and maybe you did too) to lessen the resistance when turning the crank 360 degrees. And I was replacing them anyway. Glad to hear everything is a ok!!

Des Moines, Iowa - I was born and raised there. Still get back there every year. I lived in the Drake neighborhood most of my life. Moved to the Dayton, Ohio area about 10 years ago.

Yes, I am happy and most importantly, my wife is also happy.

[TexasHonda]

Glad it worked out.

Wives don't ever forget episodes like this, and any future problems usually bring accusing questions about whether repairs were correct.

regarding automanualsource, they've always been pretty quick to send download instructions in past. How slow were they? On one occasion, I lost my manual when my PC crashed. I asked for a backup and they enabled me to download again for no charge. I now backup everything.

good luck

[phins2rt]

Originally Posted by envisionelec

Des Moines, Iowa - I was born and raised there. Still get back there every year. I lived in the Drake neighborhood most of my life. Moved to the Dayton, Ohio area about 10 years ago.

Yes, I am happy and most importantly, my wife is also happy.

hello from a fellow Iowegian!

[envisionelec]

Originally Posted by TexasHonda

Glad it worked out.

Wives don't ever forget episodes like this, and any future problems usually bring accusing questions about whether repairs were correct.

regarding automanualsource, they've always been pretty quick to send download instructions in past. How slow were they? On one occasion, I lost my manual when my PC crashed. I asked for a backup and they enabled me to download again for no charge. I now backup everything.

good luck

Five and a half hours.

My wife was sure I'd fix it even when I'm unsure. She says "You always say you can't and then you do..."

She's my biggest cheerleader (and was one in highschool...haha).

[MDXROCH]

Little too late for you but I experienced this when I did mine. I posted it in the forum awhile back about it.

7. Check & Correct Crank, front and rear Camshafts are at (TDC). Repeat the entire Install process. My back cam came off alignment while installing the belt. It can come off easily due to cam tension. Check and Check…………

[TexasHonda]

There's a very good video (2-part) on Honda/Acura 3.5 V6 Timing Belt work by realfixesrealfast. He has some tips to avoid TB jumping while installing.

MDX Timing belt, replacement - YouTube

MDX Timing belt, replacement - YouTube

good luck

[mowashear]

wow i thought this vehicle was trashed...

good to hear