Mechanics - please help!

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Here's the whole story start to finish - can you help?!?


day 1 - 1981 olds Delta 88 .... 307 V8 ran rough but ran. I changed plugs, wires, distributor cap, and changed oil. Cranked it up, ran GREAT...... until I put in reverse or drive (it would die).

day 2 - got a mechanic to come out and look at it - he moved wires around thinking the firing order was off for over an hour until giving up (I replaced plug for plug, wire for wire) Either way it would not and will not start now.

day 3 - new mechanic comes out and plays with firing order - again no start. He cleaned all spark plugs (which where nasty by the way) but no start. Oil was seen spitting out of carb :/

day 4 - myself and a friend came out - spark plugs are creating spark. We believe that firing order is correct - 1,8,4,3,6,5,7,2 - and we believe that we found the proper "1" location from the rotor. Still no start.


Other facts - I changed oil and it was about a quart to much - also added 2 quarts to bone dry tranny fluid that I checked in day one.





ANY IDEAS AGIANS?!?!??! IM STUCK AFTER 3 SEMI PRO MECHANICS!
 
GM Products, some one may have had the ditributor out of the car and installed with #1 in another spot on the distributor cap. Remove #1 spark plug bring the engine to compression stroke on #1 cly, algin the Ign timming mark on the balancer to TDC. Remove the distrubutor cap and check where the rotor is pointed at in relationship to #1 plug wire.
Retime if needed. It is possible the timming chain has jumpped.
 
GM Products, some one may have had the ditributor out of the car and installed with #1 in another spot on the distributor cap. Remove #1 spark plug bring the engine to compression stroke on #1 cly, algin the Ign timming mark on the balancer to TDC. Remove the distrubutor cap and check where the rotor is pointed at in relationship to #1 plug wire.
Retime if needed. It is possible the timming chain has jumpped.

A bit confused - We put the belt to 0 and saw the rotor pointing to "1" - is this what you meant?!?!? We did the butt test 2 times in a row to confirm this.
 
If you see that you have a good hot spark but it will not turn over you should check to see that it is getting fuel. If not you may have a bad fuel pump. If it is getting fuel you may have a large vacuum leak. The EGR valve could be stuck wide open if it is a EFI engine. If you are getting fuel and no major vacuum leaks then it could be a broken timing belt.

Good luck.

-Sparty
 
If you see that you have a good hot spark but it will not turn over you should check to see that it is getting fuel. If not you may have a bad fuel pump. If it is getting fuel you may have a large vacuum leak. The EGR valve could be stuck wide open if it is a EFI engine. If you are getting fuel and no major vacuum leaks then it could be a broken timing belt.

Good luck.

-Sparty

Ok cool - definitely getting fuel! - large vacuum leak could be an issue... but would that keep it from starting?!?!?! EFI ENGINE? What is that exactly?
 
Ok cool - definitely getting fuel! - large vacuum leak could be an issue... but would that keep it from starting?!?!?! EFI ENGINE? What is that exactly?

EFI - Electronic Fuel injection, basically a modern engine that a computer controls the air:fuel ratio, non carb

Really if you've played with the firing and timing, im guessing its not there, kinda hard to say when you cant see or hear the engine.

I gather its cranking and just not starting

Im not a fan of throwing parts at car, but new plugs wont hurt her. If there was too much oil in the car that could've "soiled" a few things but its hard to say, find a good mechanic.

best of luck to you!
 
I've never seen a fuel injected carberator...I've seen fuel injected throttle bodies.

He did say carberator in his post. Make sure it's a carb you're looking at (I think it is) and not a throttle body Anthony. That will make all the difference in the world in getting proper advice. I've never seen a 307 from that year have a fuel injection system. I'm not saying they may not exist, I'm saying I've never seen one.
 
1981 v8 carburetor no computer,

If gases are blowing out from the car, A spark plug wire is crossed or the timing chain has jumped. I suggest removing spark plugs and check compression with carb held wide open.

That model also wears lobes off the camshaft.
EPA took the zinic out of the oil, which increased camshaft lobe wear.
 
Yeah guys, this is old school. A 1981 307 should have a Quadrajet carburetor, HEI distributor, & a timing chain (not a timing belt). There should never be anything spitting back from the carb. Whatever the liquid was, it shouldn't have been doing that. Usually, what causes that situation is the spark plug firing out of time (while the intake valve is still open). So I can see why your other mechanics were looking at the firing order. Next, the new spark plugs should not have been dirty. Especially if you were suspecting a large vacuum leak which would create a lean condition. Lean=dry & golden brown. Rich=wet & black. It sounds like you started the car cold after the tune-up. You put it in gear & it died. Probably because either it was too rich or too lean. The chances that it chose to jump time right then are extremely remote. I believe we eliminated the lean condition with the 'dirty' plugs. So, maybe this is just an extreme case of flooding. Try this. Take the air cleaner off the carb so you can watch the choke flap. Push the accelerator to the floor & hold. Crank the engine over & keep cranking for a while. If it starts to hit on some cylinders, you know it was flooded. You're trying to get as much air as possible thru the engine to dry the plugs out. If you try this & get nothing, you can go the opposite direction & try a squirt of starting fluid while cranking. All of this information is assuming you don't have a spark or timing problem but this is where I would start. Good luck!
 
Hey Anthony,

Happy Thanksgiving! :props:

Here is the correct firing order for your engine.

Firing Order: 1-8-4-3-6-5-7-2

Olds.jpg


The car did run before the tuneup and oil change....so that's good. It appears to be running rough and the reason for this are many; ignition system, ignition timing, fuel-air mixture, vacuum leaks, moisture, carburetor, valves, cylinder compression etc.

To me it sounds a lot like valve timing which means the distributor could be out of position. Each car has a spec for timed ignition firing but as engines age and parts wear these might not work. Typically I'd attach my timing light to the #1 wire to check the timing on an engine while it's running. Normally, the timing marks should line up nicely for the engine to run well but as I said, older engines with a lot of miles may need additional advance for this to happen.

To determine what's going on will be a process of elimination..

First - those mechanics should have determined the correct firing order in their books or on the internet then checked to see if yours was correct...

  • Use the diagram above to check off the firing order question.
  • Enure wires are fully inserted in the distributor cap sockets and the moisture boots are seated around the posts. I typically spray some silicone on the tops to make these easier to seat.
  • Do the same for the spark plugs.
  • You didn't mention it but did you touch the distributor timing?
  • Is the distributor cap fully seated against the distributor face?
  • Clean up an old spark plug and insert it in the end of each wire and ground it. Now crank over the engine and check for spark. If all 8 exhibit the same amount of spark check off the wires, cap, rotor, and coil from the list of possibilities.
  • Be sure all the vacuum lines are plugged in, even the one coming from the distributor. These old distributors relied on vacuum to either advance or retard the spark timing in order to keep the engine running smoothly at different rpm's.
  • Try using starter fluid. Most starting fluids contain ether which is very flammable hence the reason we used to use them.
  • If the engine is popping back through the carburetor it's an indication of incorrect timing or a valve that temporarily hung up. If the engine pops back through the carburetor and flames then this is an indication of the spark plug firing while the intake valve is still open...again, timing.
  • A bad distributor might also be the cause.
I would go through a full check to ensure the distributor is set on cylinder 1 while it's on the compression stroke at top dead center. This will ensure that the basic distributor and camshaft timing it set correctly. I really suspect it is since the car ran smoothly after you tuned it up.


Check for vacuum leaks as this could be the main culprit here.
 
Lets see if we can troubleshoot from the beginning...


day 1 - 1981 olds Delta 88 ....

307 V8 ran rough but ran. -> Here's where you start -> it ran


I changed plugs, wires, distributor cap, and changed oil. Cranked it up, ran GREAT......

--> Sounds like you did everything right and fixed the original problem.


until I put in reverse or drive (it would die).

Here's where you start troubleshooting, everything was normal until now.


The first thing that comes to my mind is either,

Timing is way off and no power
You can have a traditional V8 and have it run good but have no power if the timing is way off.

Electrical
When you were messing around in the engine compartment something was "touched" that might have to do with power, ignition and shifting.

The electrical issue sounds pretty far fetched but I've seen some wacky electrical problems. Keep in mind you said it ran great until you moved the shifter... (doesn't matter the direction), this is where you start to troubleshoot.

What changed?


If it ran bad before you tuned it up but would continue running after you put it in either forward or reverse gear this is a baseline, the car was operational.

You tuned it up and then it ran great but stopped running great when you put it into gear.

What changed?


Nothing you do during a tune-up should affect the running of the engine when you shift the shifter. That's common sense.

But still, something changed and now the engine dies when you move the shifter.

So it's either related to the shifter and possibly something electrical.

Or

When you put a load on the engine, (Going from neutral to placing the transmission into a gear is putting a load on the engine), now the engine dies.

The demand for power is greater than the engine running system can supply so it dies.


Electrical - Something isn't making a good connection or any connection.

Mechanical - Timing belt could have jumped a tooth, if this is the case you need to replace the timing chain you cannot "time" the bad running condition out of the engine by adjusting the timing.

Fuel - Starving for fuel. This is where anyone that messed with the fuel system after you tuned it up may have caused the problem.


day 2 - got a mechanic to come out and look at it - he moved wires around thinking the firing order was off for over an hour until giving up (I replaced plug for plug, wire for wire) Either way it would not and will not start now.

But it ran great before, after you did the initial tune-up.


day 3 - new mechanic comes out and plays with firing order - again no start. He cleaned all spark plugs (which where nasty by the way) but no start. Oil was seen spitting out of carb :/

But it ran great before, after you did the initial tune-up.

day 4 - myself and a friend came out - spark plugs are creating spark.

That's the first thing to check. :xyxthumbs:

We believe that firing order is correct - 1,8,4,3,6,5,7,2 - and we believe that we found the proper "1" location from the rotor. Still no start.

That's the correct firing order but it's possible to have a distributor 180 degrees out.

There's a couple of ways to put #1 piston at top dead center during the firing phase, one is by placing your finger on the spark plug hole and then bumping the engine over till you feel the air being pushed out while looking at the harmonic dampener and watching for the timing mark to rotate just in front of or behind the 0 mark on the timing tab indicator.

Another way is to remove the valve cover and watch the rocker assembly open and close the valves as you rotate the engine over. After you see the intake valve close, watch to see the timing mark approach the timing tab and when you reach the mark on the harmonic dampener reach the 0 degrees you'll be at top dead center during the firing cycle.

Now look to see where the rotor is pointing, remember that and place the cap on the distributor and whichever terminal on the cap it was pointing to place #1 Spark Plug Wire on this terminal and the other end on the spark plug and then continue installing wires in the correct order.

After this you'll want to check the timing with the vacuum disconnected if you have a vacuum on the distributor.


I've worked mostly on BBC but this style is all pretty much the same and very simple to work on. This is my daily driver, a 454 BBC, I assembled it and installed it all myself...

JimmysNewTop03.jpg



I actually wrote a how-to manual called,

How to Adjust the Chevrolet Valve Train using the E.O.I.C. Method


:)
 
WOW EVERYONE! I LOVE AG! Thank you all for responding and helping - that rocks! I am reading while cleaning for Turkey Day so I don't have time to individually thank you all for your help - but I am soaking in all the info and it really helps guys! What am I thankful for on this Thanksgiving Day - AUTOGEEK AND ITS MEMBERS!
 
Cranked it up, ran GREAT...... until I put in reverse or drive (it would die).

Sounds like the choke pull-off (vacuum diaphram) on the Quadrajet is bad. The pull-off allows the chokes butterfly to stay closed during engine warmup then allows the butterfly to open during acceleration to keep the engine from loading up (flooding). This is a common problem with Q-Jets. The choke pull-off can be checked with a vacuum pump or even sucking air through the vac line to see if it holds vacuum.

Double check your timing order with #1 @TDC ( finger in #1 plug hole until compression pushes it out). Place a large screw driver in the carb holding the choke's butterfly open so it can't close and load up the plugs again... then crank.
 
A lot of great information here!


Basics: Motors have 4 cycles. Intake, compression, power, and exhaust...


Checking rotor position...



  1. Clean the harmonic balancer to ensure the timing line is clearly viable.
  2. Clean the timing marker on the block to ensure the timing line it too is clearly viable.
  3. Rotate the crankshaft until the two line are lined up.
  4. Remove the distributor cap and check the rotor contact position is pointed directly at the number #1 terminal. If it is then you're good to go, if not then it needs to be repositioned.
  5. If for some reason it's pointed in the opposite direction don't panic. The cause is more then likely you're on the exhaust stroke and not the compression stroke. If this is the case, rotate the crankshaft 360 degrees more clockwise looking at the front of the motor until the timing marks are once again lined up..
  6. The rotor position should now be pointed at the #1 terminal on the distributor cap.

GM motors have gears on the base of the distributor and they can be a little tricky to line up correctly with the camshaft gear but for the most part can be 1 or 2 teeth off. If this happens then simply pull it out and reposition it until the rotor is lined up on the #1 position.


Chrysler distributors had a key instead of a gear so it's either in or 180 degrees out...


Let's talk about removing the distributor.


For some reason in the 80's, GM motors with the distributors in the rear tend to seize up in the intake manifold therefore are a bear to remove or even turn for that matter. Soak the area in penetrating oil and tap the distributor with a mallet while twisting. A rubber band wrench will also help if it's stuck.

Now look at the carburetor and vacuum lines, modules, and connections...
 
  1. Rotate the crankshaft until the two line are lined up.
  2. Remove the distributor cap and check the rotor contact position is pointed directly at the number #1 terminal. If it is then you're good to go, if not then it needs to be repositioned.
  3. If for some reason it's pointed in the opposite direction don't panic. The cause is more then likely you're on the exhaust stroke and not the compression stroke. If this is the case, rotate the crankshaft 360 degrees more clockwise looking at the front of the motor until the timing marks are once again lined up..
  4. YOU should now point the distributor at the #1 terminal on the distributor cap

Fixed ^^^

I agree Bobby but It's actually better to physically point the rotor at the #1 cylinder on that bank, then correlate the wires to the cap 18436572 (counter clockwise Olds)



The only way to have a baseline (in order to not be chasing your tail in circles) is to verify #1 is @ TDC by either finger in the #1 cyl, bump starter until compression pushes finger out OR like Mike posted, observe the intake valve fully opening then fully closing then bring balancers timing mark to TDC. (I do the latter on builds where the engine is on the stand)


You need to verify this because their maybe other issues keeping the engine from starting. I do agree that if someone thinks they have rotation 180 out... that this might bring it to spec. But when it still refuses to start... you think "did I have it right the first time before I 180'd it "
 
Fixed ^^^

I agree Bobby but It's actually better to physically point the rotor at the #1 cylinder on that bank, then correlate the wires to the cap 18436572 (counter clockwise Olds)



The only way to have a baseline (in order to not be chasing your tail in circles) is to verify #1 is @ TDC by either finger in the #1 cyl, bump starter until compression pushes finger out OR like Mike posted, observe the intake valve fully opening then fully closing then bring balancers timing mark to TDC. (I do the latter on builds where the engine is on the stand)


You need to verify this because their maybe other issues keeping the engine from starting. I do agree that if someone thinks they have rotation 180 out... that this might bring it to spec. But when it still refuses to start... you think "did I have it right the first time before I 180'd it "

I agree! :props:

Now, there used to be a little gizmo that screwed into the spark plug hole that had an indicator that popped up telling you when you're on the compression stroke. I haven't seen one of these in years but if you have short fat fingers or the hole is extra deep they did come on handy.

Oh yea, having the valve cover off makes it so darn easy to determine just watching the valves....:props:
 
Anthony, I'm curious to hear any update you might have.... :props:
 
What am I thankful for on this Thanksgiving Day - AUTOGEEK AND ITS MEMBERS!

This is just one of many things I'm thankful for, but...

I have to agree with you. So many people on this forum have been a huge help to me, including you Anthony. :xyxthumbs:
 
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