The other night I was cruising on my way home from work and noticed the ALT light flashed and the car turned off. I tried cranking the engine but it sounded "too fast" and I thought - no compression.

I instantly looked at the timing belt and cam gears and could see the gears were not lined up. Turns out my timing belt lost several teeth so I had it towed.

I removed the valve cover to begin to determine how much damage has been caused and noticed the cylinder head has an oil "tint" and would like to know if this is normal or should it be shiny clean. I am **** with maintenance as this is my daily but the car does burn more oil tan it should but I constantly monitor it and have an oil pressure gauge on the A pillar.

I can spin the crank easily and the camshafts too (albeit a litttle harder than the crank of course) so I think I can eliminate the possibility that binding caused the timing belt failure. A friend mechanic told me maybe some road debris got into the belt since I don't have the upper cover installed. I do this so I can see the cam gears which are adjustable.

My plan is to replace the belt, start the car and check compression. If there are no bent valves, I'll call it a day. If I have to replace the valves, I'll refresh the head and replace the wáter pump and tensioner.

What are the common causes of timing belt failure? Thanks for your inputs.

 

The color is normal. Its just oil varnish or some crap. You should see an engine with 200k+ miles on it. Smells rank.

Do you have aftermarket valve springs? How old was the belt? What brand? You probably bent the valves. Reset timing and crank it. Itll be obvious pretty quick

 

Yes, the head is built but the most it sees is 8500 occasionally since it only has Type R cams. Brand is Skunk2 Tuners. The belt is probably 10 years old so I gues I was pushing it ;-)

 

More than likely

I have seen the coloring on the cam caps and what not before, but wouldn't call it "normal". Just means the oil wasn't changed very frequently (forgot about).

This is my motor with 140,xxx miles on it.

Should stay like this past 200k miles if it is cared for

 

And you made this post so we could tell you what exactly? That yes you should have changed it and now you potentially have to rebuild your motor cause even though you are "**** with maintenance" you somehow kept driving on a 10 year old timing belt and revving out to 8.5k. We're here for you...

 

>> And you made this post so we could tell you what exactly?

Basically, if the oil "tint" on the cylinder head is normal.

I know I pushed it but the failure happened during normal driving - not while revving it to 8.5k which I only did maybe once a week to put a smile on my face. Not looking for hugs or pity - I will use this "event" to rebuild the head if necessary on my own sans the tasks only a machine shop can perform.

Live and learn ;-)

 

Dude 10 years is double the service life of a timing belt. Regardless of milage they must be charged after 5-6 years.

Live and learn I guess. Bet after the hundereds and hundereds youll end up spending fixing it you wont let a 50-100 dollar timing belt get used past its recommended life span

 

I feel the pain..my t-belt was also missing about 20 teeth two weeks ago.. it's just about done.. Mine did have 8 exh. valves bent and 1 intake valve bent (ferrea valves)..all the rest of the valvetrain was intact and good.. I also have the valve cover bare...There are ways to figure out if the valves are bent without actually trying to turn the car over and risking more damage than there might already be.

 

Yes, by testing for compression leaks right?

 

You can also check the valve clearance, if any are way loose they are likely bent or not seated properly. There is more clearance on the intake side of the pistons so odds are you would have exhaust valve issues more than intake.

 

Thanks for the tips PSI and Tamparican. This is the type of information I was hoping would be posted so I can attack this issue using what we call in IT "Best Practices"!

 

I also had that oil tint when i pulled my valve cover. I just cleaned it up in the parts washer at my shop, but if you wanna be **** you could try Purple Power degreaser to clean it up a bit if you don't have access to a parts washer.

 

If I haven't bent any valves and I don't have to pull the head I'll just leave it alone. If I have to pull the head then I'll follow your suggestion - thanks!

 

Ok, so I was preparing to replace the timing belt and wanted to make sure the water pump, tensioner and camshafts weren't binding and I think I have an issue with the exhaust cam.

The intake cams rotates freely 4 times but the exhaust seems to bind on the 4th turn. Could this be the reason my timing belt was damaged or am I being too critical? I'm thinking maybe I should adjust the valves first?

I shot a quick video - please comment...

 

And just so you know, if you didnt **** up the engine by destroying the belt, you probably did now. You should NEVER rotate the cams without the timing belt. Unless you made sure every piston was rotated to the halfway down point, the valves are gonna crunch Into the pistons.

 

Yes they were all level

 

Good lol, i kid you not ive read people spinning the cam till it binds from p2v contact and mess up the valves.

Anyways, theres a chance the valve is bent. Try checking the rocker clearence and see if any are way big like someone mentioned earlier if you havent yet.

Another thing you can do is put a belt on and do a leakdown test.

 

If the valves are bent, is replacement feasible with a good DIY write-up (have never done it myself) or should I just take it to a machine shop? I'm thinking the replacement valves won't seal properly out of the box and need to be lapped against the valve seats...

 

I bent every valve in my head and swapped used valves out of another and it ran fine. I dont recommend it because the valves were probably loose in the guides, but it ran fine.


Theres also the chance your guides are damaged too. Honestly I would bring it to a reputable machine shop to have them inspect it and see what their opinion is

 

Ok, thanks m4x!

 

For those interested in knowing the outcome of this thread, I replaced the timing belt and adjusted the valves. Some were slightly loose and others way tight (I think this added to the belt failure).

I purchased the following tools and followed standard procedures found in the Acura service manual. The engine started right up and idled perfectly. After warming up I took her out for a spin and put a smile on my face again ;-)

 

Good stuff man.