I recently completed my 3.4 build-up! I installed a new cam with new timing gears. Now presuming I installed it correctly by matching up the timing marks at the #1 piston at TDC. With timing and cam installed correctly, I bolted and assembled the engine... And now its sitting in the car and it won't start. I checked the timing by setting the engine at TDC with the marks on the harmonic balancer near or at zero with the timing plate case (engine front case) and what seems to be the #!1 pistons at the top. I pulled the plugs to make sure I was getting fuel and the plugs were wet/fuel present. I checked to see if there was spark by pulling the spark plug and cranking it over and there was spark. My question is, what can I do now? My engine still won't start.

Guess the first thing to try is check the plug wires are in the right order and possible flip the dist. 180* to see what happens.
I'll be at the same place in about two weeks with my 3.4 hope I have luck.

Make sure your not 180 degrees out on the distributor... take out the #1 plug and have someone put their thumb over the hole and crank the engine over by hand or tap it over with a starter button. When you feel compression pushing the finger/thumb off the spark plug hole... your on the compression stroke, continue turning slowly until your timing mark is pointing at correct timing. Pull the distributor cap up and look to see which spark tower the rotor is pointing at. You'll probably find it is point away from #1... if so, re index the distributor so that it's pointing at the #1 plug wire tower in the cap. Might want to install a fresh set of dry plugs and try starting it again.

Can I assume you did remark the damper with a new mark for TDC or used a 2.8 damper?

I am not sure but i heard if u had an 88 you can use the stock 2.8 damper so I think I am ok there…but I think ill try the 180 and the finger in the hole to make sure I am on the up stroke thanks guys

When my 3.4 wouldn't start after the build, it was the oil pressure sender. People had a big debate about it and wiring diagrams were brought out, but in the end, fixing that connection solved the no start issue. People disagreed on whether or not the ECM turns off the fuel if it gets no signal from the oil pressure sender. On my car, it does apparently.

Just a side note after you flip the distributor around 180 and get the engine started, remember to ground the a&b terminals in the aldl connector while your timing it...

Ok I am sure I got the timing right cus it turns over smoothly and no back firing =) thanks for that one guys. The bad thing is it still does not fire up and suggestions, I know I am getting fuel and spark hmmmm

Are you sure your getting fuel and spark. If you are getting those two and air it should fire. You have to be missing something. Is there good spark to all the plugs.

Did you try starter fluid down the t.b.yet? If it kicks in for a couple seconds, then look towards the fuel system malfunction. Is your coil ok.

I know its funny that I have the 3 things it take to fire it up…but still nothing I checked for spark with an inline spark plug tester and it glows but I only checked it on the #1 piston…to be for sure I guess ill do all 6 of them…and I tried the starting starter fluid and nothing, it didn’t fire up…which leads me to think that maybe I am not getting spark in all cylinders…I think my coil is good cus when I pulled it off and cranked it over it heard it spark…I am not sure about much anymore…but ill willing to keep trying anyone’s advise

Have you removed your oil fill cap and watched as it's cranked to see if the lifters are moving. Did the valve lash get set correctly. IE are you valves moving.
Did you prefill your lifters before you put them in and adjusted lash?
You could also pull the air duct and feel if the engine is pulling any air when cranked.

[This message has been edited by Dodgerunner (edited 10-29-2006).]

Do you hear the F.P. relay click and the fuel pump kick on for 3-5 seconds.. Like dodgerunner is saying on the air---maybe have someone hold their hand over the t.b. while your cranking the engine. Ignition modual check out ok?

Ok so first thing I should do is have some one crank over the engine and see if it is pulling in air and have the oil cap open to see movement of the rockers? Then if it is not sucking in air or I cant see the movement then that means I have to adjust the valve lash? Is there any way of taking off the valve covers with out taking off the middle manifold? I have the lifters soaking in oil for a few days before I installed them and set it…I am just not to sure if I adjusted it right… the book says to turn it tight to where u cant turn the push rods and then back it up a half of a turn right? This is the first engine I ever assembled so I had a lot of uncertainties.

no, you don;t loosen it 1/2 turn, you tighten it!!!!

to set lash on a dry motor, tigten the rocker down till the pushrod won;t pin, or you start to feel the drag on it. if the intake is off, watch for when it just starts to move the cup off the retaining spring. then, if using stock studs and lifters you turn it in 1 and a half more turns to compress the lifter and set it to it's middle of travel. called preload. if you are using the sbc studs with the course thread, then turn it in 1/2 turn.

if you loosened it 1/2 turn after it touched, then your valves are probably barely opening, if at all!

now I think if you have a 1/4" drive with a felxshaft you might be able to get the rear valve cover off, you will have to remove the dogbone bracket. I don;t know if the front is possible or not.

I swapped in a 3.4 from a 95 firebird a few years ago into a T-Top'd Formula I had from college. I had the exact same problem you're having and it was very frustrating. I focused mostly on timing until something clued me into the fact that I was getting too much fuel. Let me ask you -- you say your plugs are wet.. are they too wet? One of the injectors that came with the 3.4 was stuck open which flooded the engine. Pull your dipstick and check to see if it reeks of fuel. When I drained my oil, a quart of fuel was mixed in.

They need 3 things to run....

1. Suitable compression.
2. A suitably strong spark delivered at the correct time
3. The correct mixture of fuel and air.

Everything else is fluff.

Let's start with the basics and approach this methodicallly;

A. How many pounds of fuel pressure do you have at the schrader valve? Shoot for between 35-45. If it's any less or more, we have an issue there. I see so many threads where somebody says "I push the valve stem on the rail and fuel comes out". That's nice....but how many pounds of pressure? 10 lbs will cause fuel to run out....but it won't start the car.

B. What are your compression readings for each cylinder? This is critical on any engine...but on a fresh rebuild, it raises an eyebrow for me because so many things can go wrong.....cylinders not honed correctly, stuck valves and lifters, misadjusted valves, timing chain and or gears off, etc. Low or uneven compression readings tell us a lot. Now is the time to run the test.

C. Let's check that ignition timing one more time. Assuming you have good compression and the valve timing is correct, the next thing to check is if it's getting fire. Index the distributor so that the timing is correct....ie....TDC for cylinder #1, rotor pointing at #1. That's good enough to start it...we can adjust once it's running. Also....let's reexamine that spark. You mentioned the plugs are wet....as in fouled? As in fuel dumping into the cylinders? How strong is the spark....nice and blue hot....or weak and pale yellow?

Do those three things....and tell us what the results are and we'll go from there. If you satisfy the three requirements I set forth above....it WILL run. It has to....laws of physics.

As a side note....the oil pressure switch has....listen carefully everyone...ABSOLUTELY NOTHING to do with the fuel pump running or the engine starting if the fuel pump relay is working. It only comes into play as a backup if the fuel pump relay fails. It doesn't factor into your equation...so disregard it completely. This issue has been beat to death on every GM forum I've ever seen...yet there is still bad info out there and people claiming the car won't start until 4 psi is reached. Hogwash. Only if the relay has failed....which our old friend the fuel pressure gauge can tell us. If the engine has sufficient fuel pressure it will start and run with ZERO oil pressure....at least until it locks up.

Happy wrenching....keep us posted.

Yeh, what Frizlefrak said! I went through the same thing last December. The first issue was the distributor timing was too far off. After I got it to start, then I found that it was missing and had almost zero compression in one cylinder. I had set the valves about like you did; I tightened them until the push rod didn't spin and then another turn for good measure. So I had to pull the intake and valve covers. I too questioned myself if I had indexed the cam and crank correctly. After all, the one mark was barely visible, the lighting was poor, and I was in a hurry. Good luck and keep us posted.

Tom

I got home today and I was only able to try the suction on the TB it didn’tt feel that strong so I am thinking that I should reset the valve lash...now that I am sure of the proper way to adjust it...I also checked the oil if gas leaked in, and the oil was good (no smell of gas in it)...it’s a good thing that members of this forum provide strong support to people like me that aren’t so sure...ill fallow the steps that Frizlefrak said and ill check in as soon as I’ve tried those things

The biggest thing on setting the lash is the feel of when the rod reaches zero lash. You want to just "feel" the resistance it will never get so tight you can turn it. I like what one person said, he moved the rod back and forth and felt for the clicking to stop. You just have to develop a feel for the zero point.

Your probally not going to like this news--but you`ll need to remove the intakes/plentum to get the vavle covers off, they have the middle one, angled just right so you can`t get a socket on a couple of the vavle cover bolts. Maybe we should see if Rodney would invent something that would work on those things..It`s so close.....

You never indicated you turned the distributor 180 degrees, you said that you had spark and no backfire so you know you are okay there. I have made that mistake before and I didn't get any backfire while attempting to start the engine.

Also on the spark, I always check mine with a spark plug and look for a blueish color spark, if it's orange/yellow in color it's not strong enough and will not ignite the mixture.

I would have performed a fuel pressure test and a compression test by this time.

I reiterate....tell me how many pounds of fuel pressure you have before you touch anything else. If it's between 35-45, and holds pressure for a reasonable amount of time when you turn the key off, we can eliminate a fuel system issue and move on.

Then run the compression test before pulling your (intake and) valve covers. If you have solid compression across the board, you shouldn't have a rocker arm adjustment issue.

Fuel pressure test = extremely simple
compression test = simple
Pulling intake to get to valve covers = difficult (particularly if you didn't need to).

I am a HUGE believer in running tests. The "spray and pray" method may evenually unearth the problem, but for those of us short on time (not to mention money), it's not practical nor fun. Use a methodical process of elimination. Start with the fuel system, move on to compression, then go to ignition. The problem lurks within one of the three components.

It would be a major bummer to do all this work and then discover that a weak fuel pump or dead regulator is causing all this grief. Conversely, if you have a cylinder or 2 with 0 compression, you know EXACTLY where to start looking. If fuel pressure if good and doesn't leak down, and compression is solid across all 6 cylinders, we know we have an ignition system issue. Then it's just a matter of eliminating ignition timing / weak spark as a factor.

1. suitable compression
2. Suitably strong spark delivered at the correct time
3. Correct fuel air mixture.

Which one of the three is deficient or missing?

Just to contribute my 2 cents here. I just recently finished doing a rebuild on my engine, and had a -very- similar problem. What was discovered was the new piston rings hadn't sealed/seated yet and thus weren't holding compression. To get the engine to give its initial start, we needed to retard the timing about 15 degreese. This was necessary so that the vapors could be ignitied before they were lost through the fresh rings and valves. After a couple minutes we slid the timing back towards 'normal' and all was well. It starts on the first hit. I dont fully understand all the physics that apply to starting a freshly rebuilt engine, but as I understand and have experienced it, this is the easiest way to do it.

Ok so, I tested the fuel pump with a gauge and it held at 40 psi I check it twice. The first time with the key in the on position and the second time in the off position. I had the gauge on the hole time I was removing the spark plugs and it held constant I then ran the compression test and that didn’t look to well the # 1and 5 were about 140-150 pis and #3 was about 130-140...on the other side didn’t look to well the #2and 4 was low around 85-90 psi and the #6 was high at 160-170 does that sound or look right??

quote Originally posted by Carenath: Just to contribute my 2 cents here. I just recently finished doing a rebuild on my engine, and had a -very- similar problem. What was discovered was the new piston rings hadn't sealed/seated yet and thus weren't holding compression. To get the engine to give its initial start, we needed to retard the timing about 15 degreese. This was necessary so that the vapors could be ignitied before they were lost through the fresh rings and valves. After a couple minutes we slid the timing back towards 'normal' and all was well. It starts on the first hit. I dont fully understand all the physics that apply to starting a freshly rebuilt engine, but as I understand and have experienced it, this is the easiest way to do it.

VERY GOOD POINT
Had that scare a couple of weeks ago during a compression test on the 3500 I'm preparing for my swap after forgetting it's an interference engine and turning the crank by hand and bumping a valve. Cylinder #1. 90 cylinder #2. 244 almost three times higher, the engine only has 7000 miles on it and someone mentioned that the rings had not fully seated yet. Each succeeding test resulted in #1 pressure going higher and higher with a final reading of 170 and I expect all of them to even out once it is actually started.

I think your compression is good enough to at least let it run on most cylinders(mine had worse than that before I replaced it). As yours is not running on any cylinders, I'd go back through the ignition timing issues one more time. Here goes: pull the #1 plug(the one closest to the dog-bone) and place thumb/finger over the opening(not in it); have someone "click" the engine over a bit at a time until you feel that whoosh of compressed air past your finger; use a wrench on the crankshaft pulley bolt to move the timing mark(which should be very close) back to TDC(I painted a mark 180 degrees from the timing mark so that I could tell when I was close to TDC while laying under the car); check the distributor and make sure the rotor is pointing to the terminal that will feed the plug wire going to the #1 cylinder(closest to dog bone- you may pick any terminal at this point); then, make sure that the remaining terminals(in a clockwise manner match the firing order(is it 1-2-3-4-5-6?). Another thought. You might pull the plug off of the cold start injector if you decide to pull the distributor as it's easy to get to at this point (don't lay it on the crossover pipe-don't ask). This may eleminate some of the "wet plugs" symptoms you are getting.

Happy Halloween!

Thanks for all the advice and suggestions which was very useful! I made really good progress today… I checked all the spark plug wires to see how much spark they threw out. Also bought new AC Delco R-42TS spark plugs. I think the spark plug gap is .040. Does the gap really matter? I’ve read on the forum that most people run .045. As far as the spark, I’m not sure what the blue spark everyone keeps talking about. Hmmmm. If anyone has a pic of how it should look like or any methods to test if the spark is strong enough, that would be greatly appreciated!

After installing the new spark plugs and testing the spark wires, I had about 9-12 OHMS of resistance in all of the plugs. I fired it up and sound much better this time! Like it was actually going to start! What else do you think I should do guys?

..

I make a living as a mechanic and someone has already given you the answer. Your valve lash is wrong. Your plugs are gas fouled because the valves are opening enough to let gas dribble through. You have good spark, and even at 180 degrees off it will run but backfire. Fuel pressure is correct and the compression check is ok. The compression is ok because your valves are pretty well closed. The one thing you lack is AIR! Fuel will not detonate in your combustion chamber unless you are at least around 10:1. You are at about 3:1. Adjust your valves to zero lash and then 1/2 turn MORE. Turn the key and fire it up. Keep us posted....

------------------
carpe diem

quote Originally posted by frankenfiero1: I make a living as a mechanic and someone has already given you the answer. Your valve lash is wrong.

And I'm betting the issue is on cylinders 2 & 4.


Low compression is caused by only a few things.

1. Blow by on compression rings due to wear, new rings not seating, improper honing on cylinders, or broken rings.
2, Blown head gasket, cracked head, or block.
3. Leaking or misadjusted valves.

I'm voting for #3 on your engine. Set the lash as Frankenfiero laid out. I would readjust all 12. Set the engine on TDC on cylinder 1 (both valves closed), move pushrod between thumb and forefinger and tighten nut until resistance is felt, and then another half turn. Rotate the engine 120 degrees ( 1/3 revolution) and do the next cylinder in the firing order. Rotate another 1/3 and do the next, and so on, until you've done all 12 valves (2 complete revolutions). NOTE: This would be every 90 degrees on a V-8, or 180 degrees on a 4 cylinder.

I highly suspect you'll find no preload on the lifters on cylinders 2 & 4. Reset your valve lash, and run your compression test again. I bet all 6 cylinders are now very close.

One quick test is to squirt some oil down the plug holes of the cylinders with low compression. If compression suddenly comes up....you have a ring or cylinder wall problem. If not, it's either a valve train issue or leaking gasket / head / block.

You're getting there....keep plugging at it. At least now you've eliminated the fuel delivery system. Let's get past this little compression glitch, and I'll bet it fires. If not, the only thing left is an ignition / ECM issue. And we'll test until we figure that out too.

thanks guys for the advise ill do so this weekend

Or you can set #1 TDC on the firing position like you have before by feeling the spark plug air.
You can then set:
Exhaust on 1, 2, 3
Intake on 1, 5, 6

Turn engine one time around back to TDC and do:
Exhaust 4,5,6
Intake 2,3,4
Just remember the Exhaust valves have the extra metal shield on them.

Oddly enough that 120 degrees or 1/3 revolution happens to line up with the 3 grooves on your dampner, if you start the # 1 as TDC with the widest groove, I did a write up on this a couple years back, I painted all 3 marks different colors, as I had the heads off and could see when all the pistons where at top dead center , I did this and wrote it down somewhere, that way I wouldn`t have to guess at it--it was so easy that it got over complicated on the thread and people had a tough time trying to understand it, I will try to look it up for you, try vavle lash or my user name or both. If you have any questions about that method post away or pm me..

Dodge runner's method is the easiest. one rotation and all the valves are set.

Just remember one thing, if you have all stock components, when you reach 0 lash you turn in 1.5 more turns. this is due to the fine thread on the stock studs. if you have other studs in there,(ie sbc studs with aftermarket rockers) they are usually a course thread, and then you only do 1/2 turn in.

Since your intake will still be on, I'll mention how I find 0 lash without being able to see the cup of the lifter, I posted this once before:
grab the pushrod with the rocker slightly loose. hold the rod UP into the rocker arm. wiggle it side to side, and you should feel it tick against the sides of the cup in the lifter. slowly tighten the rocker , you will feel the side to side play lessen as it moves into the cup. when you feel it gone altogether, try to spin it, you should feel slight drag . recheck for wiggle, if still gone, then you can set the lash in by tightening as above the porper number of turns for your studs.

it sounds long, but after you do one and get the feel, you can do the rest fairly quickly.

tjm4fun I used your method when I did my 3.4 and liked the feel that gave. After checking the position/travel of the lifter "pistion" I decided to only go 3/4 of a turn in. Will see how that works out in a couple weeks when I fire up the 3.4.

Heres the old thread --I only copied out the method I used as not to get things to confused. Another note is you can switch the colors as I did after this and changed the widest groove to white, for timing reasons--non the less--you can change the colors before you start or after for timing reasons, just make sure that you change all 3 colors in a clock wise rotation and write then down for later reference..

I did find out something interesting while I was doing this, and that is you can mark your dampner with 3 colors to take out the guess work while lashing vavles. There are 3 grooves on dampner, the widest one is your timing groove, heres what I did allthough I can see when # 1 is TDC.

* . Find TDC for # 1 by hand cranking --look for # 1 lifters to stay motionless , then you`ll see # 6 lifters/pushrods just start to move up a little, look at dampner and you`ll see the widest groove is very close to --0--.On the timing tab, Mark that widest groove with Black, turn clockwise and mark next groove white, then next groove red. Then make a full 720 rotation to get back to # 1 TDC starting point.

1. Adjust # 1 with dampner at 0 and Black mark showing.

2. Move black to white ==adjust # 2

3. move white to red=====adjust # 3

4. move red to black=====adjust # 4

5. move black to white ===adjust # 5

6. move white to red=====adjust # 6

Move red back to black and your at TDC for #1 which was the first one you adjusted *Your Done*

You can also put your fingers in the open plug holes , once the air has blown *Past* your finger, your at TDC for that cylinder so you can adjust accordingly. Another way is if the dampner is off the engine "measure it" or this will work if you know what size dampner is too. Take that measurement of dampner --divide it by 3.14, ie. 8 X 3.14 this will give you a measurement of about 90 degrees in which you would want to rotate to find TDC for each cylinder.

quote Originally posted by Dodgerunner: tjm4fun I used your method when I did my 3.4 and liked the feel that gave. After checking the position/travel of the lifter "pistion" I decided to only go 3/4 of a turn in. Will see how that works out in a couple weeks when I fire up the 3.4.

I was really at odds with myself on that 1.5 turn thing. I always set my lifters light, and that was bothering me. I did settle on the 1.5 only because I assembled the motor the first week of january in an unheated garage at around 40 degrees or less, with new lifters.
a dial indicator said that the lifter preload was correct at 1.5, but it still seemed too tight, but the motor does run perfectly and sows no sign of valve float at 6000 rpm.
next time I have the covers off, I plan on machining in a removable center plate so I can adjust them after the fact, as I am planning on putting in 1.6 lifters when I find some extra $$.

quote Originally posted by tjm4fun: Next time I have the covers off, I plan on machining in a removable center plate so I can adjust them after the fact, as I am planning on putting in 1.6 lifters when I find some extra $$.

That would be really nice if you where messing with them much. Would beat taking everything off to do them.

Any updates? We're all waiting to hear "I adjusted my valve lash and it fired right up...WOOHOOO" or something like that.