I got the intake leak all fixed up, got all of the valves adjusted, made darn sure that when #1 was on top that the rotor pointed to #1 wire, I rolled the motor over with the coil wire off to circulate the new oil to flush some contaminates, the coil arced from the post to the intake so I?m sure that I had spark (then I pulled the coil input wires). Once I changed the oil and put the coil wires on, it sounded like it coughed up through the intake maybe once. I can hear the fuel pump coming on, but does it take some time to fill the fuel rail again? Everything looks right but no fire, any suggestions from you guys who have done these 2.8s before?
No, I made sure that all pushrods and rockers went back exactly where thay came from. Do I need to build fuel pressure before it will start. I have been cranking it and it sounds like fuel and air gurgling into the fuel rail. I actually got a small putt out of it so far.
usually all you need to do is turn the key on for a few seconds, turn the key off and let it sit for a few seconds and then cycle the key again. this usually primes it well enough. You can also un-plug the distributor and crank for a few. If you have been cranking on it for a while I would suspect you have primed the system and something else is wrong. I know you said you made darn sure that when number one was on top the rotor was pointing to number one, but you could be 180 off. It needs to be top of the compression stroke (both valves closed). Distributors can be kind of tricky. Several times I have been quite sure I was doing it right and still some how managed to be wrong. And just for future knowledge, the reason I asked about the push rods was because the intake and exhaust rods are different lengths. if you mix them up it will bend valves. The only GM engines that I know of that are like this are the 60 degree V6s. 2.8, 3.1 and the late model 3400. There may be more, but I'm not sure.
Gorilla, you have apoint there, maybe I am 180 degrees off. Unfortunately these 2.8s are a pain and you can?t remove the valve covers to look at the valves once the intake and fuel rail is back on. I have rolled this motor over and nothing hits, I hope that it means that everything is OK. I knew about the different push rod lengths and I made sure to remove/install everything exactly where it came from. However, my son put the last of them in and I told him how important that it was, I assume that they are all correct. I did pull #4 pushrods and compare them at one time, they looked the same to me unless they are real close in length that you wouldn?t notice it. What is a good way to be sure that I?m on the right stroke at this stage?
It's easy really. Just pull the #1 plug and blip it around (short taps of the starter as you don't want to go too fast) and when the pressure pushes your finger out of the hole (oh yeah, put your finger in the hole while you do this) your one the compression stroke. Now line up the timing mark, and get the distributer in the right position and it should be good.
> > > > > > > > > > You didn't get the pushrods mixed > up did you? > > > >
Gorilla, I got disgusted and pulled the whole top off of the motor again. After verifying everything, cylinder #1 was on the compression stroke and the distributor is pointing to #1 as it was supposed to be. I called a friend of my fathers who used to be a Chevy mechanic. He told me that the info that I got from the manual on tightening the valves may be incorrect. They say spin the pushrod and tighten the rocker until it quits spinning, then add 1 1/2 turns. I know that this gives me an adjustment that is tighter than it was when I removed it. I counted the turns just in case and every rocker nut was 12.5 - 13 turns in. He thinks that the valves are too tight and they aren?t closing causing it not to fire. What do you think about the tightening proceedure?
> > > > >> > > > > > You didn't get the pushrods mixed> > up did you?
I thought you said they were the crank down rockers ? We said before if you needed to know how to adjust them just ask. The procedure is simple if they are adjustable... It should be about 1 turn but it has to be checked at the right time. You want approx. .100" preload on the lifters. If you need the order to adjust I can look it up and post it.
> > > > >> > > > > > You didn't get the pushrods mixed> > up did you?
I thought we determined the 89s did not require adjusting? Maybe I am wrong, but I thought it was a torque spec. If I am wrong and they do require adjusting then it is possible that they are too tight. This would cause it to not run, and pop out the intake, and the exhaust for that matter. I know all of the early nineties and up are just torqued down to, if I remember right, 26 pound feet. Sometimes I find that when getting frustrated with a car that wont start I forget to look at the basics. My suggestion is this: Forget what you have done so far. Including the intake, for now. You need 3 things for the engine to run. You need fuel/air, compression and spark. Find out what you don't have. If you have spent any time cranking this thing over you could probably pull a plug and at least smell fuel if the injectors are firing. remember that is just a quick check. what I like to do for checking spark is to disconnect AT the plug and stick an old plug in the wire and open up the gap another .030 inch or so. take a jumper wire and ground it on the hook looking electrode. have a helper crank the engine over as you hold it by the wire, not the plug, you don't want to get zapped. Also make extra double sure there is no standing fuel around from checking fuel pressure or disconnecting lines. With if fairly dark you should see spark jump the gap. The reason for opening up the gap is that spark may jump the specified gap and still be weak. If it can't jump .060 or .080 then you don't have enough spark. If you are going to do much of your own engine work you really need to get a compression tester. I would at least get one from SEARS, a junk one from an auto parts store would work maybe once. In my experience at least. If your valves are too tight you should notice too little psi on the gauge or not holding any pressure. I guess a massive vaccum leak would cause a no-start. Let me know what you find after this.
> > > > > >>> > > > > > You didn't get the pushrods mixed>> > up did you?
Don't forget..... fuel/air, compression, spark..... including timing.... spark is no good at the wrong time. If it's 180 out it'll pop and sputter... to be repetative make sure it is up on the compression stroke at TDC and pointing towards #1 ... Also double check the plug wires are on correctly.. (in right order)..
> >> > > > > > > >> > > > > > You didn't > get the pushrods mixed > >> > up did you? > >> > > > > > >> > > > > No, I made sure > that all pushrods and > >> > rockers went back > >> > > > exactly where > >> > > > > thay came from. > Do I need to build fuel > >> > pressure before it > >> > > > will start. > >> > > > > I have been > cranking it and it sounds like > >> > fuel and air > >> > > > gurgling into > >> > > > > the fuel rail. I > actually got a small putt > >> > out of it so far. > >> > > > > >> > > > > >> > > > usually all you need to do > is turn the key on for a > >> > few > >> > > > seconds, turn the > >> > > > key off and let it sit for a > few seconds and then > >> > cycle the > >> > > > key again. this > >> > > > usually primes it well > enough. You can also > >> > un-plug the > >> > > > distributor and > >> > > > crank for a few. If you > have been cranking on it > >> > for a while > >> > > > I would > >> > > > suspect you have primed the > system and something > >> > else is > >> > > > wrong. > >> > > > I know you said you made > darn sure that when number > >> > one was on > >> > > > top the rotor > >> > > > was pointing to number one, > but you could be 180 > >> > off. It > >> > > > needs to be top of > >> > > > the compression stroke (both > valves closed). > >> > Distributors can > >> > > > be kind of > >> > > > tricky. Several times I > have been quite sure I was > >> > doing it > >> > > > right and still > >> > > > some how managed to be > wrong. And just for future > >> > knowledge, > >> > > > the reason I > >> > > > asked about the push rods > was because the intake > >> > and exhaust > >> > > > rods are > >> > > > different lengths. if you > mix them up it will bend > >> > valves. > >> > > > The only GM > >> > > > engines that I know of that > are like this are the > >> > 60 degree > >> > > > V6s. 2.8, 3.1 > >> > > > and the late model 3400. > There may be more, but > >> > I'm not sure. > >> > >
When I pulled it apart for the second time I found that the fuel rail was full, so I have fuel. I rolled the motor to the compression stroke of #1, plug wires were right. I have spark because it will jump from the coil to the intake with no coil wire. The rockers are adjustable, and believe me I have adjusted them 100 times already. I set it on #1 and follow the correct order-Exhaust 1,2,3 - intake 1,5,6..then roll it to #4 and do the rest. The manual said tighten the rocker until the push rod will not spin, then add 1.5 turns. I have been told by two mechanics that this is too tight and the valves are not closing. Unfortunately with a 2.8, you cannot remove the valve covers without removing the intake plenum and fuel rail to adjust them with the motor running. Today I was told to adjust out the lash and add 3/4 to 1 turn. I don?t know anything at this point excapt that I?m really beginning to dislike 2.8?s LOL!
> >> > > > > >> > >> > > > > > You didn't> > get the pushrods mixed> > >> > up did you?> > >> > > > >> > >> > > > > No, I made sure> > that all pushrods and> > >> > rockers went back> > >> > > > exactly where> > >> > > > > thay came from.> > Do I need to build fuel> > >> > pressure before it> > >> > > > will start.> > >> > > > > I have been> > cranking it and it sounds like> > >> > fuel and air> > >> > > > gurgling into> > >> > > > > the fuel rail. I> > actually got a small putt> > >> > out of it so far.> > >> > > >> > >> > > >> > >> > > > usually all you need to do> > is turn the key on for a> > >> > few> > >> > > > seconds, turn the> > >> > > > key off and let it sit for a> > few seconds and then> > >> > cycle the> > >> > > > key again. this> > >> > > > usually primes it well> > enough. You can also> > >> > un-plug the> > >> > > > distributor and> > >> > > > crank for a few. If you> > have been cranking on it> > >> > for a while> > >> > > > I would> > >> > > > suspect you have primed the> > system and something> > >> > else is> > >> > > > wrong.> > >> > > > I know you said you made> > darn sure that when number> > >> > one was on> > >> > > > top the rotor> > >> > > > was pointing to number one,> > but you could be 180> > >> > off. It> > >> > > > needs to be top of> > >> > > > the compression stroke (both> > valves closed).
Well at this point with out being there to see it for myself I don't know what else to tell you. I guess I would try the 3/4 to 1 turn thing. Lots of luck. Let me know what you find out in the end.
> > >> > > > > >>> > >> > > > > > You didn't>> > get the pushrods mixed>> > >> > up did you?>> > >> > > > >>> > >> > > > > No, I made sure>> > that all pushrods and>> > >> > rockers went back>> > >> > > > exactly where>> > >> > > > > thay came from.>> > Do I need to build fuel>> > >> > pressure before it>> > >> > > > will start.>> > >> > > > > I have been>> > cranking it and it sounds like>> > >> > fuel and air>> > >> > > > gurgling into>> > >> > > > > the fuel rail. I>> > actually got a small putt>> > >> > out of it so far.>> > >> > > >>> > >> > > >>> > >> > > > usually all you need to do>> > is turn the key on for a>> > >> > few>> > >> > > > seconds, turn the>> > >> > > > key off and let it sit for a>> > few seconds and then>> > >> > cycle the>> > >> > > > key again. this>> > >> > > > usually primes it well>> > enough. You can also>> > >> > un-plug the>> > >> > > > distributor and>> > >> > > > crank for a few. If you>> > have been cranking on it>> > >> > for a while>> > >> > > > I would>> > >> > > > suspect you have primed the>> > system and something>> > >> > else is>> > >> > > > wrong.>> > >> > > > I know you said you made>> > darn sure that when number>> > >> > one was on>> > >> > > > top the rotor>> > >> > > > was pointing to number one,>> > but you could be 180>> > >> > off. It>> > >> > > > needs to be top of>> > >> > > > the compression stroke (both>> > valves closed).>> > >> > Distributors can>> > >> > > > be kind of>> > >> > > > tricky. Several times I>> > have been quite sure I was>> > >> > doing it>> > >> > > > right and still>> > >> > > > some how managed to be>> > wrong. And just for future>> > >> > knowledge,>> > >> > > > the reason I>> > >> > > > asked about the push rods>> > was because the intake>> > >> > and exhaust>> > >> > > > rods are>> > >> > > > different lengths. if you>> > mix them up it will bend>> > >> > valves.>> > >> > > > The only GM>> > >> > > > engines that I know of that>> > are like this are the>> > >> > 60 degree>> > >> > > > V6s. 2.8, 3.1>> > >> > > > and the late model 3400.>> > There may be more, but>> > >> > I'm not sure.>> > >> > >>> > >> > > Gorilla, you have apoint there, maybe I am>> > 180 degrees off.>> > >> > > Unfortunately these 2.8s are a pain and you>> > can't remove the>> > >> > valve>> > >> > > covers to look at the valves once the>> > intake and fuel rail>> > >> > is back on.>> > >> > > I have rolled this motor over and nothing>> > hits, I hope that>> > >> > it means>> > >> > > that everything is OK. I knew about the>> > different push rod>> > >> > lengths and>> > >> > > I made sure to remove/install everything>> > exactly where it>> > >> > came from.>> > >> > > However, my son put the last of them in and>> > I told him how
Hopefully you didn't bend any valves. By having the 12-13 turns after touching you would have put over 1" of preload which would probably open the valve up to 1.5" with ratio of the rocker calculated in (once they pump up,
1 turn give approx. .100" preload). If you have a compression gauge I would use it and see if any of the cylinders have real low compression. As far as the 1 turn we replied a few times with that info... P.S. I think, the aluminum head uses the crank down cast heads use adjustable.
> >> > >> > > > > > > > >> > >> > > > > > > You didn't > >> > get the pushrods mixed > >> > >> > up did you? > >> > >> > > > > > > >> > >> > > > > > No, I made sure > >> > that all pushrods and > >> > >> > rockers went back > >> > >> > > > > exactly where > >> > >> > > > > > thay came from. > >> > Do I need to build fuel > >> > >> > pressure before it > >> > >> > > > > will start. > >> > >> > > > > > I have been > >> > cranking it and it sounds like > >> > >> > fuel and air > >> > >> > > > > gurgling into > >> > >> > > > > > the fuel rail. I > >> > actually got a small putt > >> > >> > out of it so far. > >> > >> > > > > >> > >> > > > > >> > >> > > > > usually all you need to do > >> > is turn the key on for a > >> > >> > few > >> > >> > > > > seconds, turn the > >> > >> > > > > key off and let it sit for a > >> > few seconds and then > >> > >> > cycle the > >> > >> > > > > key again. this > >> > >> > > > > usually primes it well > >> > enough. You can also > >> > >> > un-plug the > >> > >> > > > > distributor and > >> > >> > > > > crank for a few. If you > >> > have been cranking on it > >> > >> > for a while > >> > >> > > > I > would > >> > >> > > > > suspect you have primed the > >> > system and something > >> > >> > else is > >> > >> > > > > wrong. > >> > >> > > > I > know you said you made > >> > darn sure that when number > >> > >> > one was on > >> > >> > > > > top the rotor > >> > >> > > > > was pointing to number one, > >> > but you could be 180 > >> > >> > off. It > >> > >> > > > > needs to be top of > >> > >> > > > > the compression stroke (both > >> > valves closed). > >> > >> > Distributors can > >> > >> > > > be > kind of > >> > >> > > > > tricky. Several times I > >> > have been quite sure I was > >> > >> > doing it > >> > >> > > > > right and still > >> > >> > > > > some how managed to be > >> > wrong. And just for future > >> > >> > knowledge, > >> > >> > > > > the reason I > >> > >> > > > > asked about the push rods > >> > was because the intake > >> > >> > and exhaust > >> > >> > > > > rods are > >> > >> > > > > different lengths. if you > >> > mix them up it will bend > >> > >> > valves. > >> > >> > > > > The only GM > >> > >> > > > > engines that I know of that > >> > are like this are the > >> > >> > 60 degree > >> > >> > > > > V6s. 2.8, 3.1 > >> > >> > > > > and the late model 3400. > >> > There may be more, but > >> > >> > I'm not sure. > >> > >> > > > >> > >> > > Gorilla, you > have apoint there, maybe I am > >> > 180 degrees off. > >> > >> > > Unfortunately > these 2.8s are a pain and you > >> > can't remove the > >> > >> > valve > >> > >> > > covers to look > at the valves once the > >> > intake and fuel rail > >> > >> > is back on. > >> > >> > > I have rolled > this motor over and nothing > >> > hits, I hope that > >> > >> > it means > >> > >> > > that > everything is OK. I knew about the > >> > different push rod > >> > >> > lengths and > >> > >> > > I made sure to > remove/install everything > >> > exactly where it > >> > >> > came from. > >> > >> > > However, my > son put the last of them in and > >> > I told him how > >> > >> > important > >> > >> > > that it was, I > assume that they are all > >> > correct. I did pull > >> > >> > #4 > >> > >> > > pushrods and > compare them at one time, they > >> > looked the same > >> > >> > to me > >> > >> > > unless they > are real close in length that > >> > you wouldn't > >> > >> > notice it. What > >> > >> > > is a good way > to be sure that I'm on the > >> > right stroke at > >> > >> > this stage? > >> > >> > It's easy really. > Just pull the #1 plug and > >> > blip it around > >> > >> > (short taps > >> > >> > of the starter as > you don't want to go too > >> > fast) and when the > >> > >> > pressure > >> > >> > pushes your finger > out of the hole (oh yeah, > >> > put your finger > >> > >> > in the hole > >> > >> > while you do this) > your one the compression > >> > stroke. Now line > >> > >> > up the > >> > >> > timing mark, and > get the distributer in the > >> > right position and > >> > >> > it should > >> > >> > be good. > >> > >> > >> > >> Gorilla, I got disgusted and > pulled the whole top off > >> > of the motor > >> > >> again. After verifying > everything, cylinder #1 was on > >> > the compression > >> > >> stroke and the distributor is > pointing to #1 as it > >> > was supposed to be. > >> > >> I called a friend of my > fathers who used to be a > >> > Chevy mechanic. He > >> > >> told me that the info that I > got from the manual on > >> > tightening the > >> > >> valves may be incorrect. They > say spin the pushrod > >> > and tighten the > >> > >> rocker until it quits > spinning, then add 1 1/2 turns. > >> > I know that this > >> > >> gives me an adjustment that is > tighter than it was > >> > when I removed it. > >> > >> I counted the turns just in > case and every rocker nut > >> > was 12.5 - 13 > >> > >> turns in. He thinks that the > valves are too tight and > >> > they aren't > >> > >> closing causing it not to > fire. What do you think > >> > about the tightening > >> > >> proceedure? > >> > >
69CameroSS, I would like to see what you show as a proceedure, All I have found so far is take out the lash and add 1.5 turns.
Before I ever cranked the motor, I rolled it over with a socket and nothing hit, so hopefully I don?t have any bent valves. A couple of times while adjusting the second set of valves I rolled the motor with a socket and felt a tight spot which obviously was a valve. Fortunately I never hit the key. It seems like the adjustment is very critical, just the slightest bit overtightening and that valves will hit.
These are cast heads, I guess thats why they are adjustable. When I said 12-13 turns, that was all of the way to the end of the stud. In other words, I counted from the factory adjustment until the nut fell off the stud. The lock nut doesn?t even begin to lock on the shaft until turn #6.
You cant remove the valve covers on these 2.8s without removing the intake plenum and the fuel rail, thats why I want to be sure that these things are adjusted correctly before I button it up for the third time. I thinking of adjusting out the lash and giving it 1/2 to
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