Timing Belt Problems!!! Exhaust Coming Out Intake!!!

[FlamingWeasel]

Okay, here's my problem . I just finished installing my timing belt today and when I went to start it it wouldn't start. There's what seems like exhaust/smoke coming directly out of the intake. The smoke smells like fuel. I know there's obviously no combustion taking place in the engine. I made timing marks on the cams before i took the belt off and they're still aligned right now. The thing is, I rotated the crank to TDC like the instructions stated and left my timing marks as is. Therefore, my timing marks were aligned as they were when I took off the belt and i rotated the crankshaft to TDC. I don't know what's going on here. Do any of you think that I may have bent my valves by doing this? Can valves bend without the motor actually starting? What could possibly be the problem? I'm thinking about towing it into the dealership tomorrow and having them deal with it. But I don't know yet.... I need help, and BAD. If anyone can help me, please respond. Thankyou.

 

[i'm boosted]

It's very likely you did bend the valves. Check compression

 

[BUCK]

Originally posted by i'm boosted It's very likely you did bend the valves. Check compression

I thought it was a non-interfence motor & you seldom do that with an N/T?

 

[FlamingWeasel]

aww man bent valves... would the engine crank over with bent valves?

 

[babell2]

With bent valves it will spin over faster than a top. No compression to slow it down. I hope you didn't make new timing marks on the cam gears, there are factory ones to time to already. Last but not least with a 4G63 if you turn the engine over with the timing belt off (even by hand) you have bent valves.

 

[dwchesbro]

You can bend the valves without it actually starting. I bought my car off someone who did what you did, incorrectly installed the timing belt. I dunno if all n/t's are interference engines, but it sounds like you bent the valves. Also if you had instructions why did you make your own timing marks on the cam, theyre already there? If you did bend the vavles, the head will have to be rebuilt.

 

[psychlow]

Originally posted by babell2
Last but not least with a 4G63 if you turn the engine over with the timing belt off (even by hand) you have bent valves.

Correct me if I'm wrong, but I believe he has a 420A.

 

[Defiant]

http://members.shaw.ca/costall/1000Q/answers-maintenance.htm#whyarebeltsimportant

Did you notice any resistance when turning the engine over? Did you have the spark plugs out?

 

[BUCK]

FlamingWeasel Car: 97 Eclipse N/T
From: Salinas, CA Registered: Aug 2002
Previous thread: 420A Timing Belt Questions

http://www.dsmtuners.com/forums/showthread.php?postid=700859#post700859

I thought you'd have to drop a keeper or something to have a valve hit a piston in one of these - don't you reckon he just has a timing problem?
Hell - EVERYBODY needs to do that ONCE in their life...

BTW - you CAN lose a Timing Belt on a 4g63 and NOT bend a valve - I did it - The belt wrung teeth at the crank - the piston had dings in it from a PREVIOUS valve bending episode (long before me) & I swear there were no bent valves - barely knocked a little teeny bit of the brown carbon off of 2 valves but they were NOT bent.

 

[FlamingWeasel]

Resistance when turning the engine over? Umm, no i don't think so. It turned over like it would normally. It sounded like it was going to start but then just didn't and exhaust came out of the intake. I guess it's because i left the cam gears as they were when I took off the belt and rotated the crankshaft to TDC. When i took off the belt, however, the crankshaft was pointed straight down from TDC. Doesn't taht mean that the valves aren't in the way of the piston moving up and down? I don't know, I think i'm getting word back from the dealership today.

 

[FlamingWeasel]

And no, I didn't have the spark plugs out.

 

[BUCK]

My guess is it will be fine - no bent valves - just a timing prob - at least you had the guts to try it - too bad you didn't have some better on-site help...

 

[me612]

Originally posted by FlamingWeasel
I guess it's because i left the cam gears as they were when I took off the belt and rotated the crankshaft to TDC. When i took off the belt, however, the crankshaft was pointed straight down from TDC.

ok if im reading this right, it sounds like you are saying that u left the cam gears in the exact spot they were at when u started working, and u say the #1 piston was all the way down instead of all the up(so piston #2 would be at TDC). So u then turned the crank to bring piston #1 to TDC, but did not touch the cam gears. And then u reinstalled the t-belt. If that's the case then your timing is 180 off in all cylinders because u left your cams the way they would be with the #2 piston at TDC, but u then put piston #1 at TDC, so during the intake stroke your exhaust valves would be open, and during your exhaust stroke your intake valves would be open. that's what i get from reading this. please correct me if im wrong

 

[FlamingWeasel]

Yeah, that's what I did. I thought I was supposed to make my own timing marks. I didn't know that there were any marks on the cam gears themselves to begin with. So when I took off the belt the, the crankshaft was at bottom dead center, and I rotated it up to top dead center... So, like you said, the exhaust valve is probably opening during the intake stroke and the intake valve opening on the exhaust stroke. If this is true, would I have bent any valves? I asked one of my friend's mechanics and he said that when I would try to start it, if I was bending valves, I would hear a horrible noise, kind of a metal on metal noise. However, I don't remember hearing such a noise. It just sounded like my car was trying to start but never did and then exhaust fumes came out the intake. The dealership still hasn't gotten back to me on the situation so I don't know what's going on yet.

 

[me612]

actually now that i think about it a little longer, if your cams were 180 off... ok 4 strokes are Intake, Compression, Combustion, Exhaust. So if your cams were 180 out, then id think that the valves would open during the stroke that is there opposite. Meaning id think the intake valves would open during the combustion stroke, and the exhaust valves would open during the compression stroke. am i right or no? if that is the case, then ur exhaust valves would have been giving your pistons a high five.

 

[FlamingWeasel]

Ok, the dealership still hasn't called me back yet and frankly I'm getting pretty pissed. I've been doing some research and I found this : http://auto.howstuffworks.com/engine1.htm. I know this drawing might not be the most acurate but it's the only thing I could find. So anyways, according to the diagram, when exhaust valves open to expel exhaust gas the piston is on its way up, and when the intake valve opens to draw in air the piston is on its way down. So if I rotated the crankshaft 180 degrees, wouldn't that mean that my piston is on its way down during the exhaust stroke and on its way up during the intake stroke? Because from how that picture illustartes it, the intake valve appears to open shortly after the exhaust valve opens. Wouldn't it just mean that the piston is directly opposite of where it should be? I don't know, I'm just trying to make sense of all of this. Sorry.

 

[babell2]

To make it simple.
1. You tried to make your engine breath backwards.
2. The timing is off and will need to be corrected.
3. If it is an interference engine by turning the crank 180 deg you could have bent at least one valve. (4 cyl 8 valve engine) more if 16 valve

Wrong = Wrong

 

[Defiant]

Originally posted by FlamingWeasel
Resistance when turning the engine over? Umm, no i don't think so. It turned over like it would normally. It sounded like it was going to start but then just didn't and exhaust came out of the intake.

Sorry, I meant when you were turning it over by hand, when committing your wizardry.... er, working on the motor.

And _which_ motor IS it, anyway?

 

[FlamingWeasel]

It's a 420A engine and I didn't feel any hard resistance when turning it.

 

[FlamingWeasel]

Ok, I just got my car back from the dealership today. Luckily, I didn't have any bent valves. The technician says that my timing was just really off (obviously) but luckily no damage was done to the valves or the pistons. They just put on the timing belt and reset the timing and everything's fine now. Thanks to everyone who put in their thoughts on this problem. The past few days have been really stressful for me. The next time I do a timing belt, I'll be sure to do it right... haha Again, thanks everyone.

 

[BUCK]

I give you credit for having the guts to try - & furthermore you had the perfect forgiving engine for a Newbie like a lot of us did - unlike a whole lot of poor newbies with Turbos & Interference motors on these boards... God have mercy on them.