'69 FJ40 won't start (1 Viewer)

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Hi all,

I'm a long-time lurker, formerly owned a couple 62's and found my dream 40 this spring. Been meaning to intro here for a while, and will soon!

I've driven her a few hundred miles so far without issues, but now she won't start. Got gas, cranks, and will fire up real weak with full choke and pumping the gas. If i take my foot off it dies.

Of course I don't know much about doin stuff and probably shouldn't have bought her but am determined to learn! What is a possible culprit- fuel filter? Dirty tank?

Here's a sneak peek- more to come!

IMG_6995.JPG
 
So it WILL start, it just won’t run. Could be a clogged fuel filter. It would be cheap and easy to change and see if it helps. Or could be carb or timing issue. Both of which I have no expertise.

Nice looking 40. Need to see more!
 
If it has the 2 barrel aisan carb, there's a couple of quick things to try. Unscrew the idle/fuelcut solenoid and blow out where it screws in and clean the end of the solenoid.
And make sure it's working [ clicking when powered.]
Another thing to try is unscrew the 14mm lug just below and to the left of the sight glass and probe a air nozzle inside the hole and blow out the primary jet.

Sometimes you can get lucky and find a quick fix.
Good luck.
 
Not sure for a 69 but ballast resistor, when bad, will allow a start but will not run.

Another possible is the fuel pump is not pumping sufficient fuel.

Sitting for a long time, it usually is clogged filter or lines.
 
So it WILL start, it just won’t run. Could be a clogged fuel filter. It would be cheap and easy to change and see if it helps. Or could be carb or timing issue. Both of which I have no expertise.

Nice looking 40. Need to see more!
Right, it won't run. I checked out the filter yesterday and it seemed fuel was dripping from the tank side of the filter, so maybe it is clogged. I'll start with that, and just pinch off the lines on either side of the filter?

Thanks!
 
Ascertain the age of the fuel in the tank, as it may be bad. If so, you can drain it through the plug in the tank's bottom, but if you do that, put a new gasket on the plug. Check the inside condition of the tank from the top by pulling out the gauge and use strong light - be careful not to lose/drop any of the small gauge screws. If tank is toast, you can still buy a new one or check out a radiator shop that specializes in cleaning/resealing gas tanks.

It couldn't hurt to check out the soft fuel lines for condition. I found a number of mine were original and rotted. Marine fuel lines are high quality. Off the top of my head, I think stock is 5/16 ID and that's what I used to replace the old lines. Once they are in, disconnect the fuel filter and blow compressed air through the hard/soft lines from the tank to see if they are all clear. If you are unable to be able to hear the compressed air coming out by the end that was attached to the fuel filter, you can put a piece of paper towel in the hose end to see if it gets blown out - that's what I had to do. I'd change the fuel filter anyway, and lay in a supply of spare fuel filters.

You can check the condition of the fuel pump by pulling the top/cover to view the rubber diaphram/gasket as well as the check valves under the diaphram for condition/crud. Before removing the fuel pump cover, make lining up mark to make reassembly easier. There are partitions molded under the cover that must be properly aligned when reassembling (don't ask).

If all the aforementioned checks out, see if the carb view window shows gas at the midline after cranking, then you know you're getting a proper fuel supply. Definitely follow the other posters advice on the idle solenoid. You can query on my prior post in another thread on getting my '40 running again re cleaning out the idle solenoid, the idle mixture screw hole, and the two vents in the carb top with carb cleaner and compressed air-a number of times til all was clear. Good luck
 
Right, it won't run. I checked out the filter yesterday and it seemed fuel was dripping from the tank side of the filter, so maybe it is clogged. I'll start with that, and just pinch off the lines on either side of the filter?

Thanks!
I would think you would get more of a stream of fuel instead of a drip. It’s a lot of work (but doable) to go through the whole fuel delivery system from gas cap to carb. Crap in the tank, old lines or even a gas cap that doesn’t vent could be your problem. I was forced to do this when I got my truck due to a leaking gas tank.
 
All good advice, I will add go one step at a time and reevaluate. If you get too many parts pulled apart at one time it makes it much harder and more expensive to resolve.
 
From your other thread, I saw you have one of those chinese aftermarket carbs. I would bet that is part of the problem. Once you confirm tank is clean and fuel pump is pumping to the carb, I would start looking more closely at that carb and connections. Do you still have the original carb? if so, I would rebuild it and swap it back on.
 
Make sure that the fuel-cut-solenoid wire provides voltage when the ignition is on.

Full choke is usually only for starter-cranking, unless the carb has a choke-breaker, which your's, and mine, do not. It will need to idle with about 3/4 choke.

Have you looked at the spark plugs? What about cap and rotor? Fix the fuel leak first.
 
I’d file the points before spending $ on anything. Way too many folks these days don’t understand the basics of an old ignition system and mis-diagnose electrical problems as fuel problems.
 
So she is still running rough- this fall it was running too rich and wouldn't start, and now super lean and lugging to the point that it won't drive. I limped it to the mechanic who replaced cap/rotor, plugs/wires, compression test, etc. He's convinced it's the City Racer carb that is at fault, and thinks I should source either a Weber or OEM.

I know this is an age-old question but I need to get him a replacement carb or he'll kick me out! Anybody got any leads on either? I'd love to go rebuilt OEM as that seems like the solution. I'll keep digging on MUD but thanks in advance for any beta.
 
So she is still running rough- this fall it was running too rich and wouldn't start, and now super lean and lugging to the point that it won't drive. I limped it to the mechanic who replaced cap/rotor, plugs/wires, compression test, etc. He's convinced it's the City Racer carb that is at fault, and thinks I should source either a Weber or OEM.

I know this is an age-old question but I need to get him a replacement carb or he'll kick me out! Anybody got any leads on either? I'd love to go rebuilt OEM as that seems like the solution. I'll keep digging on MUD but thanks in advance for any beta.
I think sequence of parts changing needs to be baselined. Did it start running rough AFTER you installed the City Racer carb? Did it run OK with the City Racer carb for a period of time after installing? If it ran fine after installing the CR carb and is now running poorly, I'd be leaning towards something in the fuel delivery system. As always, follow the advice of Mark A above first, he has forgot more than most of us will ever hope to learn about these old trucks.
 
I'm pretty sure that you have a vac-retard distributor, which isn't a good fit for that carb/vac set-up. I'd cap the line if it is.

I agree. Where does that vac line attach on carb? Probably not where it's supposed to, which will make it run really bad.
 
Thanks all for the help- I talked to the mechanic today and asked him about the run from the tank to the carb, and he said it's all looking good.

I think a rebuilt OEM carb is next up given everything I've read and his desire to get the rig out of his shop! The engine is a '73 (F540328) so what year carb am I looking for? Same as an earlier F? I'll check with Mark's Offroad, but if there's anywhere else to look please let me know!
 
You cannot go wrong with Mark's OffRoad. Check those points.
 
You cannot go wrong with Mark's OffRoad. Check those points.
what's the best way to reach him? No email on his site, lots of warnings about how busy he is! Keep calling?

...I guess I could look earlier in the thread :)
 
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The only way to reach Mark is by calling him. I think I read somewhere that he was going to be out of the office until after Thanksgiving. (but I may be wrong on that.) Be patient. A conversation with Mark is worth the wait.
 
The only way to reach Mark is by calling him. I think I read somewhere that he was going to be out of the office until after Thanksgiving. (but I may be wrong on that.) Be patient. A conversation with Mark is worth the wait.
Thanks. Well I just spoke with a mentor and he convinced me to dig deeper before replacing a new City Racer carb, which is probably not the culprit. He's suggested an intake manifold leak, confirm the accelerator pump is working, and check the tank to make sure it's not full of crap. So that's the plan!
 

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