cam shaft swap help

[SappySE107]

Stock timing is fine. There is no reason to degree that cam.

[Rootie524]

then can someone please explain what is happening. if it doesn't need degreeing, and the timing marks were lined up..what went wrong? i have never been more confused in my life. same with the people helping me. we are stumped.

the only thing i can think of is (which i dont think i got an answer for yet)..can you acheive TDC on another cylinder besides the 1st. like can you reach TDC (with the crankshaft timing sprocket in the correct position) on any other cylinder besides one..or will it only have the timing marks line up when in TDC on the 1st cylinder. because if i had it the timing marks lined up before but was at TDC on say the 3rd cylinder and then i put it all back together..that may have been the problem.

so i dont need to degree and there is 100% no need for a valve adjustment..but put the cam and lifters in the right position and tighten down the rockers accordingly and it will be in sync?

[SappySE107]

The crank position via the crank gear will tell you #1 TDC position. So far it sounds like a rocker arm gave out for no reason. Exhaust pushrod on an intake valve, or coilbind are the only 2 reasons I can think of for this to happen, and those springs won't coilbind. If the pushrods are in the right order, the rocker failed on its own.

[ForcedFirebird]

Broken rocker and bent valve, but not a bent pushrod? Odd.

[Rootie524]

well i feel like such a dumb ass. after i told everyone here there is no way it was a pushrod..guess what..it ended up being a pushrod. i though we were careful when taking the old ones out and putting the new ones in. i did the box thing that is tell you to do in the haynes to keep track of them. and i think two fell through and i told my helper to quick put them back in the right spots. apparently he didnt know the right spots. so thats my fault for not checking his work. im pissed at the same time im happy because apparently the timing was spot on and everything else was installed correctly..so ive seriously been thinking about what is wrong with this car non stop for the last few days. and now i finally know what the issue is so im relieved. we had the exhaust pushrod on the intake valve. so it lifted to much, bent the valves, broke the rocker and it explains all the ticking noise because it had the shorter rod on the exhaust valve so that wasnt getting enough lift. so it explains the sudden accelerations, the bogeyness (if thats a word), and all the clicking sounds.

so i replaced the bent valve with one from another 3100 at a junkyard and the piston has no damage to it. and the pushrod is not bent and the rocker is replaced. so i'd say i lucked out. it sucks that the entire engine had to get ripped apart because of one tiny mistake. this could have been done 4 days ago if it weren't for this. but hey..im learning..its a great learning experience and at this point i know almost all aspects of the 3100 engine and where everything is and how to take it apart. so its not the worst thing ever. knowledge is key.

try not to make fun of me too bad for this. haha. im sure you all were confused as i was explaining what went wrong and insisting it wasnt a rod...oh well...haha

[1988GTU]

I'd suspect in the not so distance future that one of your valves will probably break or not seal properly.

[Rootie524]

and why is that?

[1988GTU]

The motor is interference designed.

[Rootie524]

translate to n00b talk

[Superdave]

did you lap the new valve in?

[1988GTU]

http://www.answerbag.com/q_view/7386

Off timing is a simulation of a broken timing chain/belt to a lesser extreme.

[Rootie524]

im new to this stuff..lap? lol. call me dumb but this is allll new to me. never had the engine apart more than the UIM before. so im not too familiar with different valve train things. lap the valve? the old one slid right out and the new one slid right in..what is there to "lap"?

[Rootie524]

http://www.answerbag.com/q_view/7386

Off timing is a simulation of a broken timing chain/belt to a lesser extreme.

oh ok..that makes sense..but the damage has already been done..it turns out the timing wasnt off..just the rods were swapped. so only the one valve was bent and it has been replaced..and it has a new chain on

so am i missing something why you mentioned this? because please tell me..i dont want this to get screwed up.

[1988GTU]

I didnt read the whole post . Thought you just replaced the rocker and rod and left the valve in.

Now you know.

[Superdave]

im new to this stuff..lap? lol. call me dumb but this is allll new to me. never had the engine apart more than the UIM before. so im not too familiar with different valve train things. lap the valve? the old one slid right out and the new one slid right in..what is there to "lap"?

To get a proper valve seal you need to do what's called lapping the valve.

http://www.v6z24.com/howto/valvelapping

Without doing that there is a good chance that intake valve is going to leak, basically causing a loss of compression on the 1cyl and that's never good.