3100 sfi not starting!!

[anthonyanthony]

ok just wanted to say hello to everyone i just joined and i need some help...im not sure if this is where to post my prob...ok so i have a 2001 malibu with a 3100 sfi engine...dad was driving it and it died on him...i took the top end apart found blown head gaskets...got the heads done at a machine stretched timing chain i replaced that and im not sure if i set the timing right...

someone told me that when the timing marks are lined up crank gear at 12 o'clock and cam gear at 12 o'clock #1 piston should be at TDC...im thinking the #1 piston is the one that if ur looking at the pulleys its the first one on the right? i might be wrong...well that one is never at TDC when the gears are lined up the one that is at TDC is the one next to it #3 piston...

i checked the fuel pressure and compression i had the coil packs module tested at autozone and they tested good...i checked for spark and i have spark but its weak and im not sure if its cause of the timing being off? the timing chains on the older cars i have done were easier to do

so if anyone has a diagram or video on how to set the timing on the 3100 that would really help me out...thanks for any one who can help me

oh yeah almost forgot to mention it cranks fine no sputtering or anything it just turns over

[Azrael]

Cam gear timing mark should be at 6 o'clock, pointing straight at the crank timing mark. I think cyl 4 should be starting it's power stroke and cyl 1 on it's intake.

[CNCguy]

As said, timing marks pointing at each other (12 & 6 o'clock). Cylinder 1 is the passenger side rear head. The numbers on the intake can be confusing. The numbers are on the intake runners not at the cylinder head. Be careful to properly torque the cam bolt and install the pushrods in the correct spot as they are two different lengths. Long ones go to the exhaust valves.

[anthonyanthony]

oh yeah thats what i meant crank gear pointing at 12 o'clock and cam gear at 6 o'clock...ok so the #1 piston is the first one passenger side of the rear head? i always thought it was on the first cylinder on the passenger side of the front cylinder...when i took the pushrods out i stuck them in a piece of cardboard and numbered them and put them in the same way i took them out...

so if the #1 piston is the first one on the rear head of the passenger side the #4 piston would be up too? so i had it set on #4 so im 180 off? i'll have to take the timing cover off again and set the gears again...so would the timing being off cause the weak spark to the plug wires?

so if i had my finger in the hole and have someone crank it would it be at TDC when it pushed my finger out? or is there a different way to check if #1 is at TDC? thought id add some pictures

[Azrael]

Since both gears can only go on one way, as long as the timing marks were pointing to each other then your timing is fine.

Check sparkplug gaps (0.045"), wire resistance and that the engine grounds are clean.

[anthonyanthony]

ok itook the timing cover off again and when the #1 piston is at TDC they are lined up and when it goes back at TDC the cam gear is pointing at 12 o'clock so i dont know if im 180 off...the wires and grounds are good and in my haynes repair manual it says to set gap to .060 but i got my plugs new from napa and they always come gapped...should i try turning my cam gear 180 and see what that does? do i need to put the balancer back on to see if it starts or can i leave it off? so would the timing being off cause a weak spark in the plug wires?

[CNCguy]

Your cam timing is where it should be. The cam turns 1/2 the speed of the crank since it's gear is twice the size of the crank gear. Turning the crank one revolution will only turn the cam 1/2 turn. Spin the crank one more turn and the marks will line back up.

The ignition is triggered by the crank and there is no way to get the ignition timing out by 180. This is only relevant for engines that use a distributor.

Your initial post said that it died when running. Was it overheating? Did it have water in the oil? Was it missing before it died? Perhaps there was another issue that caused it to die and the head gaskets were not a contributing factor.

With the battery properly charged you should have good fire while cranking. Check to verify your plug wires are going to the right cylinders since the numbers on the intake are confusing. If the wires are right, you have spark and it still won't start, try a shot of starting fluid in the throttle body to see if it to fire up. This will help narrow it down to an ignition or fuel problem. Have you checked the compression?

[anthonyanthony]

thanks for the reply...i asked my dad and he said it was over heating we got it towed home and the dip stick looked fine but when i took the oil pan bolt off water did come out and the bottom of the oil pan had alot of sludge...im not sure if it was missing my dad said he didnt hear anything but my mom said she heard some kinda noise then it died
i think i put the sparkplug wires on wrong since i thought the #2 cylinder was #1 i'll fix that tomorrow...i do have spark but its kinda weak...im not sure how much spark its supposed to have...i did check the compression i forgot what it was though...i had the heads checked and resurfaced and they did a valve job too...

i have a question when the #1 piston is @TDC how should the valves be and which valve is exhaust and which is intake and does it fire on intake or exhaust?

[Azrael]

In a 4-stroke cycle a piston will be at TDC twice with 1 of 2 valve configurations. At the start the intake valve will be open for the intake stroke. Both valves are closed for the compression stroke at the end of which the piston will be at TDC again. Powerstroke is next, valves stay closed. Exhaust valve will open and the piston will go up for the exhaust stroke and the process starts over. Go here if you want a visual reference on what the valves are doing for each stroke: http://en.wikipedia.org/wiki/Otto_cycle#The_Otto_cycle

My manual says that with the timing marks lined up that #4 will be at firing position so both valves should be closed. This means that #1 should be starting the intake stroke so the intake valve will be open with the exhaust valve starting to close.

[60dgrzbelow0]

Here are some handy images to warehouse in a folder about your engine...that cover cylinder positions and proper firing order in relation to the coil connections on the ICM on the 60* GM Engines...

[ShadeTreeJack]

Any updates? I have a '98 3100 that quit running. I have spark, fuel, noid light ok, compression weak, replaced timing chain and sprockets, cam sensor and 24x crank sensor.... nothing.... can I replace a 98 malibu 3100 with a '94 Grans Am 3100? I can't see a rear - 7x crank sensor on the'94 so I am figuring no..but I may not be looking in the right spot.

[Azrael]

Any updates? I have a '98 3100 that quit running. I have spark, fuel, noid light ok, compression weak, replaced timing chain and sprockets, cam sensor and 24x crank sensor.... nothing.... can I replace a 98 malibu 3100 with a '94 Grans Am 3100? I can't see a rear - 7x crank sensor on the'94 so I am figuring no..but I may not be looking in the right spot.

Not much changed on the old 3100 during it's production so there should be a rear crank sensor. It's hard to find with the exhaust manifold right above it and the transmission below.

The one thing you will have to do to use the 94 3100 is swap the upper intakes as the EGR valve changed in 96.

[anthonyanthony]

Any updates? I have a '98 3100 that quit running. I have spark, fuel, noid light ok, compression weak, replaced timing chain and sprockets, cam sensor and 24x crank sensor.... nothing.... can I replace a 98 malibu 3100 with a '94 Grans Am 3100? I can't see a rear - 7x crank sensor on the'94 so I am figuring no..but I may not be looking in the right spot.

ok i finally got my car going...the timing chain jumped put the new timing chain on and everything was lined up the reason i couldnt get it started was cause what i thought was the #1 cylinder was actually #2 so i switched the spark plug wires around and it started up...

its running fine cept for now the rpm gauge doesnt work and i dont know what id have to do to fix it?

on my 3100 there are 2 crank position sensors one is behind the balancer pulley and the other is on the side of the block closest to the firewall..it has a metal clip and a bolt in the clip...i used a 10mm socket to take it off

[fastback4]

Maybe your engines to Orange? Painting an engine increases the engines temperature by 10%

[anthonyanthony]

i need some more help!! i got a code saying p0336 and now my tach gauge doesnt work...it runs fine and starts up fine and i have another prob

i installed a new serpentine belt about a month ago and i heard something break when i checked under the hood and the end of the belt was broken...so my question is what would cause a new belt to break?