Hello all, My name is Matt, I have recently aquired a 1994 f-150 with a 4.9l inline 6. The engine has 150,008 miles on the odometer and refuses to start. Here is what I have found and done so far.

The Truck was involved in a police chase and impounded. the impound yard got the title and Now the truck is mine. Originally the truck must have run when it was impounded and now, I can barely get the engine to fire at all. I began by doing the usual checks, Fuel, power, and spark. everything looked good, so i went to check the timing, I found that the distributor was sloppy loose. and also the harmonic balance had seperated from the crankshaft pully. the balancer managed to slide back into the timing cover and pushed the cover back into the timing gears, the gears appeared ok, with a bit of scuffing on the front of them, but the teeth were not at all damaged. I replaced all the damaged parts (except the gears) and reassembled the front end. Still having the same problems. I keep moving the distributor and keep getting a few hits, and then nothing. Sometimes the engine acts like it is pre-igniting and really lugs when the starter is turning. The parts I am using are off of a core engine from a salvage yard, so I tried swapping the IAC and the Distributor, both yielding the same results. I am running out of ideas, the Check engine light cycles like it should when the ignition is first turned on, the fuel pumps are pumping, and everything is connected. I have moved the wires, checked the spark plug gaps, and verified the firing order. Is there something I am missing, Is there a special way to install the distributor? what tells the fuel injectors when to fire? It seems like everything is happening, but not at the correct time. Cap and rotor button are new looking, and I have a core engine I can pull parts from, please help.

 

make sure you set the dist right. with number one cylinder at tdc the dist rotor should be pointing at the number one plug wire.

 

If the dist apears right, it might be 360 degrees off, the spark plugs are firing on the exhoust stroke instead of the compression. You could check this a couple ways. You could take off the valve cover and make sure both valves are closed with #1 cylinder at tdc that is most accurate. You could also take out the number one plug and blast a little air in there and see if it holds (if you have a leakdown tester)
Or the easiest way, is to remve the dist. and turn engine 360 degrees.
Other then that the things you need for and engine to work are fuel (combination of gas and air), ignition (spark), Compression, and this all has to happen at certain times.
So if you have spark, Fuel, and it is timed right, then check your compression.

 

take coil wire off, so engine can't start.take out #1 plug, and stick your finger over the hole. have some one keep bumping the key, until air pressure pops your finger off the hole.stick a soda straw in the spark plug hole, and put a big socket on the damper bolt, turn back and forth until piston is at the top. watch the straw. this is top dead center[tdc]. make sure dist is pointing at #1. make sure that fireing order is correct. put plug back in, and start. remove the spout, and set timeing at 10 before tdc

 

Pretty sure I have it correct, but as I am asking for advice, I will go back in the morning and recheck that Everything is correct.
FYI about me. I am a diesel mechanic and I work on engines daily, So most common terminology I understand. I will re-check that I am on TDC Comp. in the morning, Run a compression test and if all else fails I will pull and check that the injectors are firing. I am working with hand tools only as I have no air compressor at my house, also no diagnostic equipment other that a DVOM. Thanks again and please continue to throw out any ideas.

 

You might want to check for water in the gas. One time one of my trucks sat for a while and I couldn't get it to fire up. Turned out to be the water that settled to the bottom of the tank needed to be cleared out of the system. I had to change the filter to get it to fire up. This happens to the truck every time I don't run it for a while (months, not weeks.)

Good luck.

 

might be bad gas, gas that sits too long goes bad. pull the cap and smell it if it stinks, pump it out, and put in some fresh.

 

ok, began some re-checks this morning. First I wanted to verify there was not a problem with the diverter valve, so I went to check it.... Cant find any diverter valve or any fuel pumps that are not inside the tanks??? Did the 94 trucks not have a fuel diverter valve? Rechecked the timing with the straw method, and my timing marks do not line up where they should. The piston is already on its way back down before the marks allign. So, now I am wondering if the gears could possibly been out of time or it my junkyard balancer is no good. Everything on the balancer looked good, And when checked against the broken one the marks were not in the same places. If anyone has a known good balancer, can you check and see where the deep groove on the balancer is in relation to the key way. Mine was 180deg opposite the key way. Any other ideas. Also, how is the best way to remove, and replace the timing gears? TIA

 

Did you pull the codes on it yet
on the heater fan or close to it on pass sid ia a little black box 2-3im im sizs it has lines that run to the motor and a plug try shakeing that or get on from the junk yard
mine did the same think when I got it codes pulled BP?MAP put the one I had in the shop fire up and still going

 

Pulling the codes is worthless if he can't set the timing right.

It sounds like your timing is off. You will need a timing gear puller, they rent them at parts stores and they are cheap if you want to keep them. I think I have one in my garage for that one time in 20 years when I need one.

If you look at the gears, there are two dots on them. The dots have to be right next to each other, and I believe the cam and crank are keyed so the gears only go on one way. You will have to re-align these marks. If the gears are AT ALL suspect you should replace them with steel gears.

Once the timing marks are lined up you find TDC as per the method above, and then it should fire up.

 

ok, I did pull the codes and they are listed below. As far as the gear timing, I have a set of good condition gears on my core engine, But I am not sure that the gears are my issue, unless there is a way that the ring gear section can seperate from the rest of the assembly, The timing marks were worn off when the timing cover got pushed back by the pully, but the is the extent of the damage I can see to the gears. I did use the gears on the donor to be check that they alligned. With the keyway on the crankshaft pully facing straight up the thrust plat holes were alligned, just the same as the donor engine with the timing marks alligned. We are short on cash around here, so I cannot go buying parts till I can confirm a diagnosis, or be very certain of the problem. Steel gears are definatly a consideration, I will call the parts store and see about renting the tools to change the gears over. Here are the codes, I am a little concerned about the 556 code, maybe a big part of the problem.

mem codes
116 ECT out of self test range
636 TOT sensor voltage out of self test range
114 ACT out of self test range

Continuous Memory codes
556 Fuel pump circuit Failure (but I can hear the fuel pump working, it cycled twice when I was checking the codes, just before the CEL started to flash)

 

92 93 94 95 96 Ford Econoline Crank/Harmonic Balancer:eBay Motors (item 350279723155 end time Dec-15-09 15:13:54 PST)

this is what my balancers timing marks look like. so I guess I am swapping the gears for now. Cant seem to find the Gear installers anywhere.

 

The first three codes are because the engine isn't warmed up, so don't worry about those. The 556 code would concern me too, but if you are hearing the pumps run then I wouldn't put a lot of faith in that code.

I didn't mean to say that the gears themselves are the problem. What I didn't say very clearly was that from your OP the gears might be damaged or skipped, and if you were worried about them/thinking about replacing them anyway then the steel gears are a nice upgrade option. The plastic gear set does break/shear from time to time, but these engines also regularly run 500,000 miles without a rebuild so it's not like it's a major concern either.

If they don't look too damaged I would re-use them without worrying about it. Also remember that vehicles that were involved in polices chases recently were usually not driven conservatively right before you get them.

 

I know it is kinda scary the history it may have!!!!!!!!

 

Yeah, not sure how true it is, but that was the story I was told. The interior is in really good shape, so at least I know the truck wasn't treated like total *****. Still trying to find the right tool to pull the cam gear and the tools to reinstall both gears. So far I am only pulling parts from the donor engine till I get all the right tools to go from start to finish with the job. Do you think it is possible to change out the gears without having to pull the radiator again. I have pulled that damn thing out about 3 times already. Tired of doing it over and over. Worst case I will pull it again, I just dont like standing and laying in all that water.


Oh, does anyone know if these engines are interference engines? I may have to adjust the gears to allign the marks.