engine will not run... (1 Viewer)

[apeterson]

Okay looking for some advise.... here is the situation, truck is new to me, dont know when it last ran but... my engine will not start, here is what I know...


Did a compression test on all 6 cylinders, all tested out above 125 psi, most around 140. Which is plenty of compresion to pull the fuel through (I think). We pulled the top of the carb off and it was just full of varnish, gave it the jiffy clean up with paper towels and carb spray. Drain the fuel, which was junk and poured 5 gallons of fresh stuff in. It still doesn't want to start? It has spark, and it huffs and back fires out of the carb like it is out of time, if you pour gas down the carb., but just doesn't want to go.

The PO tryed to time it with a timing light... he says they got it back in time... I dont know how to do this, so I can not explain what he did, but I think he knew what he was doing.. He only used a light to time it... is there more that needs to be done...

Thanks for your replys in advance..

A.P.

 

[FJ40 MNTCRZR]

Sounds out of time to me, could also be crossed plug wire, check all wires,firing order and set the timing, also that carb may need rebuild.


Good luck ..

 

[Mr. Toad]

The list of potential reasons for the failure to start is long, and two or more reasons are likely working in combination.

1. That said, you'll want to make sure the entire fuel system, from tank to carb, is clean. This includes the filter that's probably clogged with varnished fuel.(Not necessarily the first step, but you'll do it eventually )

2. Next, make sure the fuel pump is delivering fuel to the carb when the engine is cranking.

3. Concerning the timing: If the engine is timed right (and your coil is good, you have spark, and the ignition system is otherwise functional), it should start briefly when you pour gas into the intake. Because yours doesn't, check the engine timing (as opposed to ignition timing, which the PO checked with a light). Make sure that #1 cylinder is at Top Dead Center when the pointer in the timing window is pointing at the TDC timing line (the TDC timing line comes around just after the BB in the timing inspection window). Keep in mind that the TDC timing line comes around twice for each ignition cycle. Every other time it comes around, both the intake and exhaust valves for #1 cylinder will be closed -- this is the one you want. When you get it there, leave your engine in this position while you do the next step.

4. Next, check that the wires are going from the distributor cap to the spark plugs in the correct clockwise order: 153624 (count the cylinders/spark plugs from 1 to 6 from the radiator to the firewall). Then make sure that the rotor inside the distributor is pointing at the terminal inside the cap that sends fire to the #1 spark plug. If it's not, then rotate the entire distributor assembly (there's a nut/bolt underneath that can be loosened to enable rotation) so that it is.

5. This gets you somewhat close in both engine and electrical timing. At least close enough to make it fire when you throw some gas down the carb.

6. Assuming these steps net you a very rough running engine, then at least you know it'll eventually work well. Now you have the fun task of rebuilding your varnished carb, chasing vacuum leaks, adjusting the valves, fine tuning the timing, etc.

Good luck. Keep us posted on progress.

 

[apeterson]

Toad thank you so much for taking the time to write that up.... it is very helpful!

concerning the timing.... is there a write up on that somewhere... I dont know what a timing window is??? where do I find that... and how do I know if the cylinder #1 is at TDC?

Sorry if these are dumb questions.... I am really really new to this!

Thanks again!

 

[fjwagon]

Timing window in located above the starter, driver side. Loosen the bolt and you should be able to see a pointer. The marking is on the flywheel and they need to match when doing the timing TDC. Marking them white or yellow is a good idea, I have these colors so that's what I use.

In the past I have bypassed the gas tank and used an gas can as the source of gas. The way I don't have worry if I emptied out all the gas or if there are other problems in the fuel sys.

 

[petescoffee]

What I have done when the distributor has been out is what was stated above and then Static Timed it.

First make sure firing order is correct as metioned above.

To static Time do as mentioned above to line up Timing mark and #1 cylinder. Then remove spark plug wire from Spark plug. Put screw driver in spark plug wire so that it is in contact with metal inside boot. Turn key to On position so that the system is energized. While holding the screw driver (hold handle with your hand do not hold metal portion of screw driver as you will get shocked) metal shaft, close but not touching the engine block, Turn the distributor slowly until you see a spark. The spark will be hard to see. Tighten distributor where it sparks.
Turn off key reinstall spark plug wire on spark plug and try to start.

Hope this helps

 

[Mr. Toad]

Timing window in located above the starter, driver side.

As described, but all that stuff's on the passenger side on my 2F jalopy. It's a rectangular hole about 1" X 1/2", and it has a long metal pointer in the middle.

. . . and how do I know if the cylinder #1 is at TDC?

You can almost assume #1 is at TDC when the timing line is on the pointer in the timing window. But remember, this happens TWICE for each ignition cycle.

The best way to determine if you're at the right place for timing the engine is to remove the valve cover and look at the valves, tappets and push-rods for that cylinder. They should be ALL be RELAXED (i.e. pushrods DOWN, valvestems UP -- meaning the valves are closed tight). (The engine will run without the valve cover)

If you happen to be "180 degrees out", then the TDC timing line will still line up in the window, but the valves for #1 cylinder will not be closed. They may appear closed, but slight rotation of the crank will start to move them. If you're here, go around again.

Helpful stuff: It's easier to rotate the crank with the spark plugs out. With plugs out, you can usually rotate the engine by moving the alternator belt. With the plugs in, you can rotate -- or "bump" -- the engine by putting the truck in 3rd gear and pushing it a little. Not very precise, though. Some use a remote starter switch. I'm not that savvy.

 

[apeterson]

Wow!!! thank you all for the info... I am printing this off and going to try it tonight!! I will let you know what happens later this evening...

Thanks again!

 

[Pin_Head]

We pulled the top of the carb off and it was just full of varnish, gave it the jiffy clean up with paper towels and carb spray.

It is best to just let sleeping varnish lie. Pushing the varnish that you can see around with a paper towel may push it into somewhere that it can do damage.

If you pour gas down the carb and it won't run for at least a few seconds, then chances are it is an ignition problem. Check for spark and if you have a spark, set the timing statically by rotating the distributor so that it sparks when the engine is set at TDC for #1 on the compression stroke. The easy way to find it is to remove the #1 plug and put your finger over the hole and then bump the starter (coil wire removed) until you feel the pressure blow your finger off the hole.

 

[apeterson]

ok I worked on this for like 3 hours.... does the timing line look like a square cut out, so I lined that up with the needle, Then I adjusted the dist. so that #1 was about touching the router, made sure the plug wires were in the correct postion, and I got nothing... I am going to try again tomarrow.... thank you all for spending the time to post... and I would really be lost without your advise..... so thanks again... I am having trouble figuring out if the valves and rods are up or down.... seems they look the same to me.. I have to keep hiting the starter because I can not move the engine even with the plugs out..

I am not giving up yet...

 

[Rocky_LC]

You might want to get a big socket on the nut at the end of the Harmonic Balancer (The main pulley that comes out of the front of the engine - this drives the fan belt). This should allow you to turn overr the engine with the plugs out.

Rocky

 

[Pin_Head]

.... does the timing line look like a square cut out, so I lined that up with the needle, ..

That might explain why it won't run.

The timing mark you want looks like a BB pressed into the flywheel and it is at 7 degrees BTDC. There is a line on the flywheel CCW to the BB that indicates TDC.

 

[apeterson]

well guys... I got it started this morning!!!!!!!!!! I was so pumped.... it does not stay running so I know I have a carb problem but at least I got it to start and run for a few seconds......

Thanks so much for all your help!!!!

 

[petescoffee]

Cool. Always a good feeling.
Now take your carb off and mail it to either Jim C. or Mark A. HAve them rebuild it and clean it for you.

Do a search and you will find the contact information for them.