[dukefame]

an alternator went out on my 2005 MDX with 240k last week on the highway. I fixed it and when doing so noticed the belt was stretched out and had a very slight tear on one part. Today the belt broke. Replaced. Now no start. cranks. Has spark. I was not driving when it died but the wife said it just suddenly died.

It is not even acting like its turning over - just a smooth silent kind of crank. I've not experienced anything like this before. Just a "whirl" no sound whatsoever. Everything is moving fine.

I did replace the timing belt just a few thousand miles ago. It's been running great since that time and it was perfectly timed.

I can't hear the fuel pump but it's pretty windy at the moment. I do smell fuel. I cranked it while spraying starting fluid in it and nothing.

Relays? could the breaking belt have hit something? I don't see anything obvious but it seems strange that the belt snapped and now this. How can it be unrelated?

Thoughts?

 

[edmmdx]

Smooth silent kind of cranking is a bad sign; remove timing belt cover and make sure timing belt is still on and has tension.

 

[2002acura]

What did you do to fix the Alternator? Did you put new alternator or used or just cleaned/rebuild it?
If not new, replace the alternator. You can try using hammer/long rod etc to knock on the alternator and see if allows you to crank/start. When alternator goes out, it make no sound/very slight sound. Good luck.

 

[habbyguy]

2002acura, I think you're conflating the starter and the alternator (smacking an alternator with a rod / hammer isn't going to do anything other than provide some exercise. ;-)

My bet is that the broken serpentine belt took out the timing belt. If you're LUCKY, it just caused it to slip a little - enough to cause a no-start, but not enough for the pistons and valves to get in a fist-fight. You need to rotate the crank to top dead center and then check through both peep holes to see if the cam timing is off (or not). My bet, that's what you'll find. There are a lot of online resources to explain how to do this (it's really simple, but much easier to learn via photos / videos than long-winded explanations).

 

[dukefame]

What did you do to fix the Alternator? Did you put new alternator or used or just cleaned/rebuild it?
If not new, replace the alternator. You can try using hammer/long rod etc to knock on the alternator and see if allows you to crank/start. When alternator goes out, it make no sound/very slight sound. Good luck.

New alternator.

 

[dukefame]

2002acura, I think you're conflating the starter and the alternator (smacking an alternator with a rod / hammer isn't going to do anything other than provide some exercise. ;-)

My bet is that the broken serpentine belt took out the timing belt. If you're LUCKY, it just caused it to slip a little - enough to cause a no-start, but not enough for the pistons and valves to get in a fist-fight. You need to rotate the crank to top dead center and then check through both peep holes to see if the cam timing is off (or not). My bet, that's what you'll find. There are a lot of online resources to explain how to do this (it's really simple, but much easier to learn via photos / videos than long-winded explanations).

I'll check for belt slippage but I'm not thinking that's the case. I just replaced the timing belt 2 K ago with all new components. It rotates smoothly so that does not indicate valve breakage etc. After further inspection I have spark, but I cannot hear the whine of the fuel pump engaging. I bought a relay and replaced it to no avail. Fuses all good. I will open the fuel line to check for pressure (not sure where to locate the pressure gauge. How can the repair manual suck this bad?)

I cannot smell any fuel when the motor cranks. I think this is a fuel issue and the sudden stoppage of the motor led to the breaking of the already damaged serpentine. This is my hope.

 

[habbyguy]

Have you checked the timing? Fuel problems won't change the sound of the engine turning over like you describe. The quick, easy way to determine if it's a fuel issue is to squirt a little starting fluid into the air cleaner and see if it fires for a few seconds. If not, cross fuel issues off the list.

 

[dukefame]

I was finally able to address this issue today. After checking both cams timing - they were perfectly aligned with one another but it seemed a bit off of the mark of the harmonic balancer. I went ahead and spent the requisite 20 minutes breaking it open. What I found inside was horrifying. When the serpentine belt went it wrapped into the harmonic balancer and disappeared. A portion of the belt was shredded and behind (and under the teeth) of the crankshaft. SO now I get to do another timing belt. Thank god they only slipped 3 teeth. No obvious knocking or bad sounds. Let this be a warning to anyone who notices a mediocre serpentine belt and doesn't immediately fix it. 20 bucks and 20 minutes could have saved me 100 and 5 hours.

 

[habbyguy]

That's pretty much exactly what I suspected (and happily, you seem to have dodged a BIG problem if that timing belt had jumped a couple more teeth).

And I couldn't agree more about replacing the serpentine belt ANY time you have to take it off (unless it's got almost no miles on it since last replacement). The one thing I'd add is that it doesn't take 20 minutes - it takes zero minutes (since you have the belt off - at last partially - anyway). Really the only extra time is weaving the new belt around all the pulleys, which should take almost no time on an MDX.

 

[dukefame]

Ya, It was literally the day after my alternator blew. I had already ordered a new belt. The good news is I'm well practiced at doing timing belts! Yay.

 

[habbyguy]

LOL. Isn't it kind of sad to get really good at doing something you really don't want to have to do? ;-)