I have a 2005 Honda Odyssey EX-L 3.5L V6 SOHC 24V with an interference engine.

My timing belt broke while driving about 20 miles per hour. As soon as it broke, the car turned off and I drifted about 10 yards to the side of the road. I tried to start the car again (not knowing that it was the timing belt), but no go. I had the car towed back to my home and hasn't move a muscle. I took two bolts off the timing belt cover to look inside to see that it was the timing belt that broke. The mechanic had replaced the timing belt one year prior, but I don't think he replaced the water pump...my guess as to the reason for the belt breaking.

I have watched many videos that say if your timing belt breaks while driving with an interference engine, you most likely have bent valves. Another video suggests to replace the timing belt, start the engine and if all sounds find, you are lucky. I am not sure what to do. I have taken the top two timing belt covers off and I noticed the front cam ironically is aligned TDC, but the top back cam is 180 degrees away from its TDC. The crankshaft is close to TDC.

I don't have the money to take the car in to pay thousands of dollars to have this done...a luxury I cannot afford right now. Any advice?

Should I pull the entire head off to have it resurface, plus the valves?

My biggest question is, if I try the simple method of replacing the timing belt, water pump, tensioner, etc. how on earth do I get the two cams and the crank all timed and aligned, since the timing belt broke while driving? If I move the crankshaft clockwise will the two cams move with it as well, even though the timing belt is broken?

I understand all the work that is required to replace the timing belt, but I am stuck whether I should remove the head or just replace the timing belt and see if the car runs smoothly. Also, I am not sure how to put it back in timing. I understand about TDC, but since the timing belt broke while driving, does that mean I have to adjust the cam and crank separately? If so, how do I do that adjustment?

 

I'm by no means a pro mechanic - so take this advice with a grain of salt.
If it were me, I'd replace the belt and try the engine.
I might also remove the valve covers and visually inspect the top-end to see if anything jumps out at you.
You will need to study-up on the cam-crank alignment procedures to be successful. I have no idea if special tools might be required.
You might also call around for a real estimate and then compare that to your DIY parts and tools estimate and then adding in your further costs if something additional breaks when you test-start the engine after the belt replacement. You'd then be making an informed financial decision about how much you're gambling.
Good luck.

 

I hae to say this....but I've never heard of a timing belt breaking and there were not bent valves from the situation. Hit up a junkyard and get a used head replacement, then do the timing belt. On this site alone, just search for timing belt broken, follow the chain of posts, and you will see....there are valves bent. every. time.

 

If you have the tools, and the time, you can get the heads off with a lot of time, but relative ease. I would suspect that you probably damaged some valves, but figuring that out with the belt broken is going to be tough without removing the heads. You really need the timing belt in place to be able to spin the cam sprockets from the crank pulley bolt and spin the 2 top cams at the same time (while keeping it all in time) to check via a leakdown test.

Don't move the cams on the heads until you get the heads off the block, as moving them can hit the pistons that look to be at TDC, then you can take a wrench and move the cams forward (clockwise) as needed. To line the back one up, you'll need a little more finesse because it will want to slam into the next stroke.

Buy an AISIN timing belt kit on rockauto, an oem head gasket, and 16 oem head bolts, you'll also find gaskets like the waterpipe gaskets that you want to replace along the way, so place the order after the car is taken apart. I like honda automotive parts.com for these parts.

Expect to spend about 15-20 hours changing the timing belt, removing the heads and putting new heads back on, it's a time consuming job, it's not hard work, but very tedious.

Take the heads off, take them to the machine shop and have them test and see if the valves are bent, they can do this with a pressure test. I paid $60/head to have them machined at my local machine shop. A honda dealer would charge 15 hours plus parts for this job.

 

deep tech GO! 360° of crank rotation, 6 pistons/crank throws, one piston is at TDC every 60° of crank rotation. (mark the crank if it helps every 60° starting at the TDC #1 mark) move the crank the the nearest midpoint between TDC of one cylinder and the next. someone check my work.

now you're safe to check current damage without creating more.

I would not go to all the trouble of installing a new belt (kit) and reassembling everything just to check for bent valves. also, it may idle and drive smoothly at first (if the damage is minimal) then throw a random misfire or lack power at any given time or condition. there is another way to check for valve leakage (bent, burnt, miss-adjusted or just missing...).

for the test, you'll want to get the rocker assemblies which will close all valves. this will allow their sealing to be checked. intake manifold plenum, and valve covers come off first. remove the spark plugs as well. carefully set the rocker assemblies aside keeping track of which goes where (or do one side, reinstall then do the other). use a long blow nozzle and air compressor (turn the regulator down so you don't over do it) to blow some air into the spark plug hole/tube. have an assistant listen and feel for air flow from the exhaust or the lower intake runners. good valves or bad a little air will probably get past the rings so ignore any crank case sounds.

this gives an idea of the severity and extent of the damage. if no noise or airflow after you check all six, then i would try installing a belt and giving it a try to see how it runs.

 

Do you recall which brand of belt your mechanic used on your Pilot?

 

If you intend on doing this yourself you may consider getting a service manual. You can rotate the cams with the head still in place you just have to back off all the valve lash Adjusters. Also you should check the valve lash before you do anything if you see one that's got really excessive valve lash, that's a bent valve

 

If you intend on doing this yourself you may consider getting a service manual. You can rotate the cams with the head still in place you just have to back off all the valve lash Adjusters. Also you should check the valve lash before you do anything if you see one that's got really excessive valve lash, that's a bent valve

 

I have changed four broken timing belts without bent valves. So it can happen. Those may not have been interference engines though because they were older cars. My daughters 06 eclipse broke one and we weren’t so lucky with that one. You can tell if the valves are bent by pulling the valve cover and the rocker shafts off. With the ticket shafts off there’s no pressure on the valves so If the valves are all the same height then you’re all set. If not, the lower ones are bent. Keep in mind the exhaust side might not be the same as the intake side.