If this thing was a horse, it wouldve been shot months ago! I got my 89 motor put in my 86 302 and everything is hooked up & ready to go. But now I cant seem to get it timed. I used a clothes hanger to see it rise/fall (#1 cyl) and made sure the rotor was at the #1 post. But it still wont fire up. Can anyone walk me through it? Or do you have any other ideas? Im thinking maybe new plug wires too. I just dont know.... Anyone want a bronco for parts?!?!?!?!

 

are you sure that you are on the compression stroke and not the exhaust?

 

i was under the impression that the compression stroke "pushed your finger off the hole" so thats the premise I've been operating under. Is this wrong? please advise.

 

Lets make sure the motor is setup properly. First take off your right bank valve cover (passenger side) pull #1 plug, crank motor till the #1 piston (very front piston on passenger side) is coming up on compression stroke, you will know this by watching your valves, as the piston is going down the intake valve (the big one)will start to open, and then start to close as the piston starts to get to the top again. Once the piston reaches top dead center this is the compression stroke, and the rotor button should be pointing to the #1 plug wire in the distributor. ( the second plug wire to the right of the hold down clamp of the distributor.If you look at it like a clock when facing it, it will be @ the 12:00 position roughly) If it is pointing to the second hole past the other hold down clamp (roughly 6:00 position) that is plug #6 and you are 180* out of timing.
Make sure your plug wires are sequenced properly. The firing order for 89 302 is as follows 1-5-4-2-6-3-7-8 in a counterclockwise rotation.

Once you get that established as correct, you have to make sure you are getting fuel to the plugs. Pull a couple of different plugs and see if there is fuel on the tips of plugs. As many times as you have tried to start this thing, there should be plenty of fuel on the tips by now. Which leads me to the next scenerio, If you have been repeadetly trying to start this thing you may have fouled out the plugs by flooding the motor, escpecially if they are champion spark plugs.

If everything checks out to be ok after all this and it still won't fire it could be possible you have a different motor in there than you think it is. 1985-90 302 HO with roller lifters use a different firing order it is 1-3-7-2-6-5-4-8.

Then my last question would be did you personally hear the motor run that came out of the donor car? If not, whos to say its a good motor and maybe there is something wrong with it to begin with. Just a thought.

 

well, heres the latest finding:
from my best judgement, id say its definitely a regular 302 because by the valve action, everything seems to be normal. the intake closes just before the rotor hits the #1 post. sooo....
my second finding: when i removed my upper intake (necessary for removal of my right valve cover), I climbed up into the motor area to check the connections to the fuel lines I made. While there, I noticed inside that I could see the tip of one of the injectors. odd. but I thought, "ok". So, just for kicks i fired her up to see if it was shooting fuel inside. no taco! I thought that since my vacuum line to the pressure reg. wasnt on, maybe that was it. no cerveza! and all this culminated with the thought that, "you know....those plugs sure are bright and shiny!" I think the one or two backfires I had while my dist. was 180* out was coincidence from something else. I know there's fuel in the rail b/c it spurts out when i push the release valve. but its not going inside the intake i dont think. any more ideas?

 

Couple of things I would look at, first when you turn the key can you hear the fuel pump in the tank engage, it will be a buzzing sound for about 10-15 seconds. If not than your not getting fuel to the rail. Second, are all the electrical connections to the fuel injectors connected. If yes to all of the above then we need to look at fuel pressure.

The main components of most EFI systems includes fuel injectors, an engine control module (ECM), an electric fuel pump, a fuel pressure regulator, and several sensors. The typical EFI fuel system uses 40psi fuel pressure across the injectors. The reason I say across the injectors is because it uses a pressure regulator to maintain 40psi pressure difference between the fuel pressure in the fuel rail and the air pressure at the injector tip. This is done by connecting a vacuum line between the air side of the regulator diaphragm and the intake manifold. When the manifold is in a vacuum, the fuel pressure in the rail (what you would measure on a gauge) will be 40psi plus manifold gauge pressure. For instance, if you have 20 inches of Mercury vacuum in the manifold (approximately negative 10psig) you will have 40psig -10psig = 30psig fuel pressure in the fuel rail. If the intake manifold has boost, say 6psig, you will have 40psig + 6psig = 46psig fuel rail pressure. The reason for this is to have a constant pressure across the injector so the flow rates will be stable for a given injector pulse width.

In the back of the fuel rail is a fitting that looks simular to a valve on a tire, connect a gauge to this and turn the key in the on position and allow the fuel rail to "pump up" and take a reading and see how much pressure you have. If its low, your fuel pump could be bad or the pressure regulator could be bad.

 

that particular valve is at the front of my rail on the left (driver) side. but thats neglegable.
when i turn the key on, actually, now i have the fuel pump on a switch under the dash (the original wiring developed a short the first time i pulled the motor out) so when i turn it on, i hear the buzzing/humming. however, it stays on constantly or at least until i turn the switch off a few minutes later. is that a sign of a problem? and that release valve shoots fuel out when i depress it so I know theres fuel in the rail. next, what kind of gauge do i use on that release valve to check the pressure? Im guessing that a regular tire gauge is incorrect... as a side note, i did notice one time that the vacuum end of that pressure reg. had a lot of junk in it that I had to pull out. Im not sure if it was there before or if it gathered it while sitting out. maybe i should replace it regardless... ur thoughts?

 

Thats a good question, never had a pump run constantly. Once it builds up the 40psi it should shut off. I believe it takes a special gauge to check the psi. Check your local parts store. But if your getting fuel in the rail and its not spurting out of the injectors, something is going on with the injectors them selfs.

 

Another thing to consider is the PCM may not be working. Or you maybe you damaged the wiring to the injectors from the computor while installing the motor, or maybe it got disconnected from the computor some how.
A fuel injector is nothing more than a high-speed valve for gasoline. An engine computer or controller is used to control the fuel injector. Contrary to popular belief, this is NOT done by sending power to the injector. Fuel injectors are normally fed power whenever the ignition key is on. The computer controls the negative, or ground side, of the circuit. When the computer provides the injector with a ground, the circuit is completed and current is allowed to flow through the injector. This energizes an electromagnetic coil inside the injector, which pulls a sealing mechanism (pintle, ball, or disc) away from its seat. This makes it possible for fuel to flow through the injector and into the engine. When the computer removes the electrical ground to the injector, the electromagnetic coil becomes demagnetized and a spring forces the pintle, ball, or disc shut to cut off fuel flow.

 

I noticed that my #1 injector was leaking the other day. Leaking where the top of the injector plugs into the rail. But I replaced it with one from another intake. When the rail is screwed down at the mounts as it should be, it leaks still; however, when I loosen both screws on that side, it seems to fit correctly without leaking. I chalked it up to being banged around once too many...despite my best efforts to be careful with it. So, anyway, now it doesnt leak. Is there anything special in the configuration that would prevent the vacuum from occuring and allowing the injector to squirt? (ie upper intake removed, etc.) It just doesnt make sense that it was all working fine when the OE motor blew & now it doesnt. Also, clarify what the PCM is, please. Thanks.
John

 

Question #2: does the 86 have an Electronic Pressure Control unit?
Question #3: could the TPS have anything to do with it?
Question #4: when the engine blew (OE), could it have screwed the ECU?

Main Focus @ this point: getting fuel into cyl's for combustion.

 

At this point it is all speculation and a guessing game. The PCM is your computor, (powertrain control module) it tells the injector when to fire like I posted in the previous post.

Vacuum has nothing to do with the injector actually firing fuel into the intake. You do need at least 35-45psi across the rail for them to work properly. The connections to the injectors must be good. Take a ohm meter and test each injector to see if they are good. Your Chiltons manual should tell you what the Ohms reading should be for that vehicle. Test your injector connectors to make sure they have continuity. Make sure your ground from engine to frame is a tight and clean one. Trace your injector harness from the injectors all the way to the computor (PCM) to make the wiring wasn't damaged while installing the motor.
On question #2 I'm not sure, I don't know a hole lot about the 87's. I will check my shop manual and see.
On question#3, the Throttle Positioning Sensor only tells the computor how much fuel is being asked for.
On question#4, highly unlikely, what did the motor actually do when it quit, throw a rod or something?

 

cool. I've got a guy coming by at 9 this morning to help out....hopefully. I'll check the harness and see. Im pretty sure the wiring is just as brittle as the rest of everything else. Nice, huh?!

When the OE engine "left the building", a lifter collapsed and summarily threw the rod from #4 down through the bottom of the block and the oil pan. It looked like someone shot a .30 cal. bullet through it. Needless to say that it shatter that end of the cam, disintegrated #4 & 8 pistons/connecting rods and marred up the cylinder walls. Directly before this happened, I noticed that all four rods on both pistons were extremely loose and was actually on my way to a place to fix them when it all happened.

 

The more I think about this, it seems that PCM is at fault here. If the fuel pump is running constantly when you turn the key on, the PCM is not telling the fuel pump relay o turn off the fuel pump when it gets the proper amount of fuel pressure in the fuel rail. Do you have the PCM from the donor car? It wouldn't hurt to try that one and see if the injectors will fire.

The Ohms reading on the injectors should be 14.7 if they are good. But I doubt all the injectors would go bad all at once. If there is fuel in the rail, the only thing stopping the injector from firing is a lack of the PCM sending the ground signal to the injector, either a bad PCM or no connection to the PCM. I would start there first.

 

One other thing you may want to check is the ground at the battery. There is usually a couple of small wires that hook to the neg battery clamp that go to different places. Check these to make sure they are connected good and not broken.