cam shaft swap help

[pocket-rocket]

but i dont get it because i put the new cam in the same way the old one was..so..im lost

It would be easy to get the timing chain off a tooth or two if you had multiple people helping. I watch over anyone that helps me like a hawk unless I know for 100% fact they know what they are doing. My one friend knows he has to anticipate my next step and grab tools before I do if he wants to have a chance at doing anything in my garage when he's over- just because I know I know what I'm doing when I put something together. I'm not saying he doesn't know what he's doing, it's just the way I work when I'm doing something out there. About the only thing I have people help me with is extra helping hands for pulling/installing engines (which most of the time I do alone), or showing a friends son how to do something to pass on knowledge.

[ForcedFirebird]

Take your valve covers back off and rotate the engine by hand. Make sure all the rockers are moving, and check for bent pushrods. The issue with it idling up sounds like a vacuum leak.

EDIT: "a tick or two" on a cam gear is a significant amount, and WILL bend pushrods depending on if you advanced or retarded the cam timing one said tooth.

[Rootie524]

well. try not to cringe too hard when i explain this. and keep in mind this is the first time im trying stuff like this and it takes mistakes to learn and it takes doing it to learn as well. i didnt expect to get it right the first time.

anyway...i took all my pulleys and stuff off and got to the cam sprocket. i took it off and what do i find..my cam is spun 180..how the f*ck did that happen? i put it in the right way..was the bolt not tight enough or something? after seeing that i thought..ok something has to be messed up so i took the rest of the engine off. the pushrods are fine believe it or not, the valve springs look good, the visible intake valves dont look bent. the only casualty i had was ONE broken rocker. it broke at the bearing. that would explain all the ticks. because the rod was still there..so everything the rod pushed up, im guessing that was causing the noises. plus the fact that i had my cam spun 180. i have no idea how it even ran like that.

so..ill be off to the junk yard tomorrow to get a rocker arm quick and hopefully get this back together right. Before i thought i had it in TDC when i put it back together. because i had the dot on the crankshaft sprocket line up with the line on the chain guide. im assuming if that's lined up that cylinder 1 is in TDC..correct me if im wrong.

so how the hell do i do this right. im going to put the cam shaft back in so the pin is pointing to the right..which will make the cam sprocket hole point down in a line..and ill have the crank sprocket marks point up..and then that should be good right? i swore thats what i did but somewhere along the line it got messed up. i have a new coyles timing chain. there are less teeth in the sprockets then with the stock ones..is it possible that threw off timing (idk why it would though)

just please someone help me. idk where im going wrong. but i got lucky im only out one rocker arm at the moment.

[ForcedFirebird]

You have to keep the matching sprockets/gears. You only changed one gear, knowing they didn't match up?

[CNCguy]

Rootie
The cam gear is twice the size of the crank gear so the engine turns two full revolutions for each turn of the camshaft. If it looked like the timing was off 180 degrees, it may have been okay since turning the crank one turn would have moved the cam 180 degrees. That would put the cam mark at the bottom and the crank mark back to the top. If you haven't already removed the timing set, turn the engine one revolution and recheck your marks.

Pushrods and valves usually bend before the rocker arm breaks. Perhaps your rocker arm was already fatigued and simply broke from the additional load of the new springs.

[IsaacHayes]

STOP

Before anything else happens.

See CNCguy's post.


Next, what year is your engine, what year timing set did you get? (94-99 had larger chain and different sprockets, 2000+ went to thinner stuff) Verify this is correct for both.. if it matches then:

I would put back on the OEM sprockets, with the new chain. I had a Cloyes set and at 180,000 miles my stock sprockets looked better quality and the new chain was tighter with the old OEM sprockets than with the new sprockets! So I just changed the chain and dampener(guide). If you have not put a new guide/dampener in, do so now.

The cloyes is not the best as far as durability. For max durability, going with OEM (dealership) sprockets, chain and dampener from 94-99 3100/3400 is the best. Especially with a cam/stiffer springs.

After you have verified the push rods are not bent, you might want to pull the lifters, or at least the one where the rocker broke and inspect it. Make sure it's not damaged or seized up or anything.

Next after you have placed the timing set back on, torqued the cam sprocket to 103ft/lbs and installed the rockers/etc. Before putting the cover back on, turn the engine by hand to verify that it's not binding on anything and looks/sounds ok. Then once you have the timing cover back on, do a compression check on all the cylinders to verify that no valves are bent and leaking. (you could do this before you put the cover on if you have an air compressor and do a leak down test instead). If that passes you've lucked out and should be good to go.

[Rootie524]

no i changed both the sprockets. i didnt just change one to the new one with less teeth and leave the other one factory. i changed both of them. i got the timing chain from a guy that was selling it on another forum..and he didnt specify what year. i thought they were all the same. but now that i think about it he had a 1999 malibu i believe..and i have a 2002..so my chain and sprockets should be the thinner kind which may be why things got screwed up. The cam is out and looks find, the springs look fine, we checked the pushrod on the valve with the broken rocker and it looked fine but im going to double and triple check though..im guessing its possible that accounted for the timing problem. having the wrong sprockets on with less teeth then what it's used to. but we did notice that when the cam and lifters were still in, some of the lifters could easily be pushed down on with our fingers..but some were stiff. so did some lifter springs break from the extra force? or is that based on the position of the cam lobes?

ill take some pictures of the timing chain sprockets if it helps or what ever else may help. but im getting the new rocker today and im going to move very very slowly. so since the cam was possibly in right, then what was the problem? the timing chain?

[SappySE107]

If the chain was 99 and the gears are 00, then that is a big problem. With the pushrods out, you should be able to press on the lifter hydraulics a little and get them to move. If not, that is probably ok anyway due to the checkball position. You could tear them apart to be sure but I doubt you broke an internal lifter spring unless the pushrods were in the wrong order.

[60dgrzbelow0]

Rootie...

Please check the mating of the broken segnents of the rocker arm... if they do not match up perfectly...then get a decent telescoping magnet that will not come apart easily and get stuck down inside the engine and fish around down inside the head adjacent the rocker post that broke, just to see if the magnet picks up any stray pieces of metal that might be laying in wait to cause trouble after your re-assemble things.

I have to say... That judging from the fact that the way you tell your story is so marvellously free of the ravages of deception and ego... that some of the best "Advisors" you could ever ask for have responded to help you and they seem to have taken you under their collective wings... I suspect...almost as soon as they were able "un-drop" their jaws after looking at your video. If this is true... then you are a very fortunate man and those of us who do not work on these kinds of engines are nonetheless reading carefully as things develop... and we are all pulling for you to make things right...

[Rootie524]

haha i appreciate all the help! its a great community.

and to answer speculation about my new timing chain/sprocket set..i believe its for a 99 3100sfi. BUT i replaced everything. the sprockets that went with it and the chain. i didnt just replace one sprocket or the sprockets with the stock chain. it's all replaced. i just assume it might be causing a problem because it has less teeth on it. but if i replace everything and it has the chain associated with those sprockets..should it be fine?

because if it could be fine then i honestly have no idea what went wrong or how to fix it. because if someone told me my cam being 180 might be normal based on where my cranks at and that the timing gears are fine..then idk what else could have gone wrong..i mean it broke a rocker!! somethings up. im pretty sure its timing..it has to be. and is everyone positive i dont need to do valves adjustments. i just put on new springs and the vavles went back to the same place after tightening the rocker arms so im guessing a valve adjustment isnt in order. so here i am back at timing. it has to be off and one tooth off on the new sprocket is the equivalent of 2-3 teeth off on the old one.

so right now (this is important that i get confirmed) i have the crankshaft sprocket on and the dont on the gear is facing up like it should be. does this determine that it is in TDC for the first cylinder? right now the cam is out and the valves are up so the crank can be turned as much as it needs to be. i guess its in TDC but it may need to be tunred a few times to get it in TDC for the first cylinder...and even when i get it in TDC for the first cylinder can i just put the cam in the correct way and put the lifters and all that back in and will my valves be lifted accordingly so that it wont hit my pistons. in simpler words..all i need to do is get the crank in TDC for 1st cyl and put my cam in with pin facing right and it will all line itself up in perfect timing sync?!

[bszopi]

If you originally had the pins lined up, then its not a timing issue. Once you get the cam back in, turn it over 360 degrees (via the crank) and look at the pins. They will be 180 degrees out. Turn it over another 360, and they will be lined up again.

As far as the rocker goes, it could have been anything really. As long as nothing looks damaged, put it back together (except for the timing cover [see above] and rocker covers) and turn it over a couple times and watch all the valves, rockers, etc. If everything looks good, button it up, cross your fingers, and start it up.

[WrathOfSocrus]

If the chain was 99 and the gears are 00, then that is a big problem. With the pushrods out, you should be able to press on the lifter hydraulics a little and get them to move. If not, that is probably ok anyway due to the checkball position. You could tear them apart to be sure but I doubt you broke an internal lifter spring unless the pushrods were in the wrong order.

With the pushrods out, check to see if the plunger comes up against the retaining clip on the lifters. If any of them don't, then it is likely sludged up. It costs nothing but time to tear open the lifters, clean them up, and oil the piston so it slides nice and smooth. The springs aren't massively strong and with enough sludge they will have little to no movement. The few engines I have torn into lately ALL had more than half of the lifters jammed below the retaining clip with no plunger movement. WOT-Tech has a tutorial of the lifters being disassembled for the LS lifter springs http://wot-tech.com/shop/all/tce-ls-.../prod_231.html

I doubt that the lifters have anything to do with the engine trouble but it wouldn't hurt to have them clean while that far in the engine. I drilled a hole in a block of wood and screwed it to another block so I could have something hold the lifter upright and keep it from rolling away while cleaning up its internal components. Also, the piston has a slight amount of clearance to the bore in the lifter and can wedge at an angle when it is part way out. Simply pulling harder doesn't work well, applying even force pulling out while trying to wiggle it back and forth a bit works much better.

all i need to do is get the crank in TDC for 1st cyl and put my cam in with pin facing right and it will all line itself up in perfect timing sync?!

Correct. The crankshaft should be at TDC on the #1 cylinder. The crank doesn't differentiate from compression stroke or exhaust stroke. That is a function of the camshaft. As Brad said, if you installed the cam dot down to the crank dot up it should be fine and the cam dot would be on top after rotating the crank 1 full turn with the chain on. I would also take his advice of turning or cranking the engine BEFORE attempting to start up

[Rootie524]

well if thats the case the timing was right. i installed the cam just like the old cam..but this isnt the old cam..so someone told me i may need to have the timing marks off for the timing to be right. he said i may need to degree the cam to account for the bigger lift that it is giving. thats the only thing i can think of. because everything else was right.

at any rate..im pretty sure one of my valves is bent (the one that had the broken rocker) so the heads are coming off now. And while they are off im going to see if someone in the area can port them a bit. and does WOT sell exhaust manifold bolts, because a lot of them are breaking.

at any rate. how should i degree the cam that it will work. because the car did idle..so its close to being in correct timing. but something somewhere is off and im very confused right now haha. ill get the specs for the cam if it will help. it has to work though because the spec sheet says its for a 3100/3400 gm engine..so idk wtf..

[95Grand-Am]

Since you used a matching timing set that should be fine, alot of people use the older style like you used as it is a little stronger. When you line up the timing marks use a straight edge, the straight edge should go through the center line of the crank and cam and the marks should line right up with the straight edge. Were you able to recover all of the roller bearing from the rocker?

[Rootie524]

ok..so the timing chain and sprockets arent the issue..i had everything lined up just like its supposed to be and i had timing issues. so the degree of my cam needs to be changed. that is the only thing i can think of. the only thing.

if this helps..specs for cam:
valve lift intake: .487
exhaust: .502

duration at .006 tappet lift (intake) 263 (exhaust) 275
valve timing at .050:
Open: Int: 5- BTDC Exh: BBDC
Closed: Int: 37 ABDC Exh: ATDC

thats all pretty much off the comp cam spec sheet that cam with..looks like the grind was originally for WOT-Tech (says so on the sheet)