Valves bent???

[TRUEeagle]

Hey guys. Quick question. For the second time my timing belt went on my 94 talon. This time i was at a standstill. Was just wondering if my valves are bent since i wasnt moving. I don't think they were. Thanks

 

[XiKeiyaZI]

Moving has nothing to do with Crank/valve movement. If your car was running, it's entirely possible. The best thing you can do is pull your head to verify. The ONLY way that you may not have is if your cam dowels were at the 12:00 position. The same may be true for 6:00. This would mean that your valves were closed and you -may- have gotten lucky as I did with my first Eclipse.

However - play it safe. Pull your head and check.

 

[BogusSVO]

Pull the VC and see if any followers were kicked off... if they were, pull the head.

 

[JusMX141]

I've seen intake valves bend from a timing jump while cranking the engine on two different occasions.

Highly likely.

 

[Calan]

Just inject some air into each cylinder while it (that cylinder) is at TDC and see if you have valve leakage...aka a leak-down test.

 

[nfernotalon]

I barely cranked on mine and didn't even start and bent a couple valves so most likely you did unless you're extremely lucky. Set the timing right and start it, if it runs and sounds lIke crap you need to replace some valves.

 

[XiKeiyaZI]

Just inject some air into each cylinder while it's at TDC and see if you have valve leakage...aka a leak-down test.

^ Or be smart and do it like this... but who really wants to be smart these days?

I barely cranked on mine and didn't even start and bent a couple valves so most likely you did unless you're extremely lucky. Set the timing right and start it, if it runs and sounds lIke crap you need to replace some valves.

^ Or... do this and potentially waste an hour or so of your life.

 

[nfernotalon]

^ Or be smart and do it like this... but who really wants to be smart these days?



^ Or... do this and potentially waste an hour or so of your life.

An hour to set timing? You're kidding right?? 15 min tops and if the valves aren't bent he's set and ready to go.

 

[Calan]

An hour to set timing? You're kidding right?? 15 min tops and if the valves aren't bent he's set and ready to go.

I think he was referring to cranking the motor over with potentially bent valves. This is never a good idea, as it can lead to more damage and there are safer ways to check for bent valves.

 

[XiKeiyaZI]

Indeed. besides pulling the timing covers, belts, pulleys, and motor mount to lower the engine, along the either removing the tire or squeezing under the tire. Aligning, setting the timing belt, bolting everything back together, assembling the pulleys and cover (I refuse to start a vehicle without the WP functioning), and ultimately starting.. I for one fail to see this being done in a matter of 15 minutes and I have dozens of timing jobs under my belt.

Overall, this is a poor way to check for bent valves as not only can it lead to further damage, it is a waste of time where other tests which would be the proper way to go about checking for bent valves could be applied. It can lead to further damage, frustration, and ultimate destruction of an engine with such methods. I, for one, do not have the virtue of patience and in an instant where I put a timing assembly back together just to find out that I had to remove it due to bent valves and remove the head anyway I would likely quit on the car for quite a while opposed to doing it right the first time and not being concerned with it.

Get my drift?

Note : there is always a 15 minute usage of time after the belt is done. Rotate - Wait. It's a basic for the tensioner to be given 15 minutes after assembly. So you will have more than 15 minutes in a timing belt job either way due to that rule alone.

 

[Boostinsideways]

This :

Pull the VC and see if any followers were kicked off... if they were, pull the head.

Then this:

Just inject some air into each cylinder while it (that cylinder) is at TDC and see if you have valve leakage...aka a leak-down test.

Really the only ways to check for valve bending with the head on the block.

 

[rlacasse1]

You will have to go ahead and time the engine to do a leakdown test in the first place. So that being said:

1: Pull the VC and look for damage

2: Time the motor.

3: Do a leak down test.

 

[Calan]

You will have to go ahead and time the engine to do a leakdown test in the first place.

He doesn't really need to re-time anything for a leak-down test; he just needs to make sure the valves for the cylinder under test are closed. It would be easier to verify with the VC off though.

 

[rlacasse1]

He doesn't really need to re-time anything for a leak-down test; he just needs to make sure the valves for the cylinder under test are closed. It would be easier to verify with the VC off though.

It just makes it that much easier in the long run.

 

[rommel rojasgsx]

Just wondering , what belt were you using and how many miles. i had a gates timing belt fail with less than 2k miles. Pull vc and most rocker arms came off. Mine happened on i95 so there was no question they were bent

 

[BogusSVO]

I will say the OP has a 95% chance of having bent valves....

So installing a Tbelt could end up a waste of time.

so If no followers are kicked off.

I would pull the cams out and the spark plugs, then do a leak down test, this way the leak down test can be done quickly, no need to move anything on the engine, since with the cams out, all the valves should be closed, if not closed, they will be bent open.

No time may be wasted installing or wating on a time belt to arrive to be installed.

It is also quicker to R&R cams than install a time belt.

 

[rlacasse1]

Agreed, more than likely there will be vent valves.

But either way, bent or not, he is going to have to end up tearing apart the timing side of the engine. So the extra 2 minutes to throw a belt on really won't be a waste of time.

If he doesn't do that he will either have to yank the cams out, or sit there and turn the crank and the cams individually to make sure the valves are closed at TDC of each piston, which would be a total b!tch.

So, it really goes either way.

 

[Calan]

I would pull the cams out and the spark plugs, then do a leak down test, this way the leak down test can be done quickly, no need to move anything on the engine

Or just pop the rockers off if necessary...even faster.

 

[nfernotalon]

It's the wheel, motor mount and the what 2 or 3 pulleys and the cover that's it . It's just another option. I've changed my timing belt in a lot before. If the op has the tools to do a leakdown test then yes best option.

Whether or not the leakdown test shows he has or doesn't have bent valves it has to come apart anyway. Might as well be halfway done. IMO.

 

[XiKeiyaZI]

This sucks man iv pulled 2 heads not a big deal
Grab a hanes manual and a couple
Friends and a case of beer:] best way
To pay your friends back good luck

Best Advice Ever.



Beer makes the world go round. Remember to report back with your results!

 

[1Gina2G]

if the engine was put back together timing wise, with bent valves, and you tried to start the motor up, would it continue to run or would you hear horrible metal on metal sound's?

 

[XiKeiyaZI]

It may or may not run. It may or may not make metal impact noises. It may or may not destroy your pistons and/or head.

It all depends on how bad it is. If the timing is WAY out and the valves are bent badly, it won't run. If the valves have already impacted and created their 'grooves' in the pistons as far as they can reach, you won't hear metal slapping noises. If they valves have not damaged anything yet or have not finished cutting into the pistons, the additional heat and impact from running the engine could destroy your pistons, crack guides, damage the head, damage cams, and multiple other things.

 

[BogusSVO]

The heads of the valves can and will snap off, getting lodged in the pistons, causing more damage.

Before you turn the key, you need to know if you have bent valves or not.

It has been laid out in front of you above.

You are not the first DSM'er to have this question or issue.

At this point, the valve bend may not be all that bad, and you man not have cracked the guides, like you would have if you were rollin down the interstate at 70.

http://www.dsmtuners.com/forums/newbie-forum/341218-how-change-valve-guides-4g63t-head.html

This shows in the first pic what bent valves look like

 

[TRUEeagle]

Well luckily for me my car did not have any bent valves. But i think the reason why my belt went was the tensioner. Cause my belt was new, probably only 1000 miles on it. It probably wasnt tight enough. The only thing off now is the timing. I have to fix that cause i definitely have a loss of power right now