74 FJ40 2f RUNS FOR SHORT TIME PERIODS

[AlexMoore91]

Hey All! I'm new to the Forum and this is my first post, so please be nice Let me preface this post letting you know that I'm new to working on an old vehicle although I've learned a lot from working on my 2010 FJ Cruiser.

Just picked up an old 1974 FJ40 a couple weeks ago that had a 2F installed by previous owner, and has the weber carb setup. Brand new Distributer cap/cables/spark plugs and several other things.

Anywho, the Fj40 will crank up great, runs and sounds good (timing seems good) to the point where I can drive it even up to 45mph pretty easily (Didn't try and go faster). After about 15-20 minutes of pretty easy driving, the engine will die. Before I fixed the timing, it would "Chug" to a stop with a lot of backfiring. After fixing the timing, the engine just died while accelerating with no backfire. At that point, it's much more difficult to start the engine, and usually requires an electrical jump if I try to restart too many times. After the engine cools and I recharge, I can go through this whole process again. Weird!

I'm trying to check everything that I can before spending a lot of money. Initial thought is FUEL DELIVERY, so I'm going to change the fuel filter since that's an easy fix. Wondering if maybe I have junk in the tank clogging up and that only kicks in after driving? Any advice on what I can check or if anybody else has experienced this?

Attached is a few pics so you can see what I have to work with!

Thanks!

 

[1911]

Sure sounds like fuel delivery to me. Change the fuel filter, replace the fuel pump, drain and clean the tank, in that order - see if one will fix it.

If it were mine, I'd s***can the Weber, but that's just me.

And welcome to Mud (< official newbie salute).

 

[JohnnyC]

You have a vacuum retard dizzy ... disconnect it ... plug the vac line... run centrifugal advance only

Set timing a few degrees higher

 

[thebigredrocker]

^what Johnny said. I've read that FJ40Jim also recommends to cap the retard dizzy and set timing to 10deg.

That is not a weber pictured. That is OEM Aisan.

 

[shawnfj40]

It has a Webber air filter is all.

 

[thebigredrocker]

Could that just be the origional 74 engine with a 2F valve cover? FYI, That cork valve cover gasket is not for a 2F cover. Perhaps it works just fine. The 2F cover uses a narrow rubber seal that fits in a channel built into the cover.

 

[AlexMoore91]

^what Johnny said. I've read that FJ40Jim also recommend to cap the retard dizzy and set timing to 10deg.

That is not a weber pictured. That is OEM Aisan.

Thanks for the clarification on the carb! That helps a ton! Wasn't 100% sure on that.

Could that just be the origional 74 engine with a 2F valve cover? FYI, That cork valve cover gasket is not for a 2F cover. Perhaps it works just fine. The 2F cover uses a narrow rubber seal that fits in a channel built into the cover.

I got the cork valve cover at a local shop, i didn't realize the original was the rubber seal until i got it all apart. I probably would go with the OEM if I did it again but it seems to be working fine. Pretty sure it's the 2f, I have the receipt from it's purchase (it was installed after the regular F engine blew up apparently).

After talking with another friend...Do you guys think it would really be a timing issue if everything is running GREAT for 15 - 20 minutes? Makes me lean towards the fuel issue, but what do I know! Thanks for all the help guys.

 

[73FJ40]

I believe the recommendations on the timing were in general, when using a vacuum retard distributor, for better all-round performance.

Fuel delivery is the most likely issue for the stall out. You should be checking the carb float bowl level through the glass window on the front of the carb. When you start up and run fine, is the fuel level in the middle of the glass, where it belongs? When it dies, is the level out of sight?

The steps identified by @1911, taken one at a time (filter, pump, tank) are (easy and cheap, a little harder and $, and more challenging and $)

 

[Spike Strip]

It looks like it has a 61031 head, which would indicate an early 2F.

Also, that's the OE Fed-spec carb, which means it has a vac advance port already. A new vac advance distributor would really add responsiveness, if that indeed is a vac retard dissy.

 

[73FJ40]

A new vac advance distributor would really add responsiveness, if that indeed is a vac retard dissy.

You can tell straight vacuum retard from straight vacuum advance by the position of the vacuum diaphragm housing . Since the rotor turns clockwise, if the housing is to the right and vacuum pulls the diaphragm 'upstream', it's advance. If the housing is to the left, it pulls the diaphragm 'downstream', it's retard.

The OP distributor picture shows the diaphragm housing to the left, ergo, 'downstream', so the vacuum will pull the 'breaker' plate clockwise, retarding timing.

I mentioned 'straight' advance or retard, because I seem to recall some diaphragm housings with two vacuum ports, one pulling the diaphragm to the retard, the other to the advance.

 

[Solace in Solitude]

Sure sounds like fuel delivery to me. Change the fuel filter, replace the fuel pump, drain and clean the tank, in that order - see if one will fix it.

If it were mine, I'd s***can the Weber, but that's just me.

And welcome to Mud (< official newbie salute).

^^X3^^ what Lee said^^

But, while you are at it, I would also disconnect both ends of the hard fuel line(s) and blow them out with compressed air, then shoot carb cleaner into the line(s) and blow them out again.

The hard lines run by the passenger frame rail and are the lowest point on the fuel delivery system... They accumulate water and crud.

Changing the fuel filter first, to a clear filter, will probably prove eye opening... You'll likely see crud in the new filter fairly quickly.

I believe the recommendations on the timing were in general, when using a vacuum retard distributor, for better all-round performance.

Fuel delivery is the most likely issue for the stall out. You should be checking the carb float bowl level through the glass window on the front of the carb. When you start up and run fine, is the fuel level in the middle of the glass, where it belongs? When it dies, is the level out of sight?

The steps identified by @1911, taken one at a time (filter, pump, tank) are (easy and cheap, a little harder and $, and more challenging and $)

To clarify... When it dies, immediately turn the key off, coast to a safe place and check the sight glass... That will leave the fuel level exactly as it was when it died.

 

[fj40cruisin]

I had the same problem when I bought my Fj40 way back when. Its a 1969 with a 1975 engine. I replaced the gas tank and it fixed the problem right off the bat. I think it was probably a combination of sitting with bad gas and junk in the tank. Good luck man!

 

[AlexMoore91]

I had the same problem when I bought my Fj40 way back when. Its a 1969 with a 1975 engine. I replaced the gas tank and it fixed the problem right off the bat. I think it was probably a combination of sitting with bad gas and junk in the tank. Good luck man!

I think you are right! Just emptied out the in-line fuel filter to find a bunch of junk! Pic attached.

 

[AlexMoore91]

I believe the recommendations on the timing were in general, when using a vacuum retard distributor, for better all-round performance.

Fuel delivery is the most likely issue for the stall out. You should be checking the carb float bowl level through the glass window on the front of the carb. When you start up and run fine, is the fuel level in the middle of the glass, where it belongs? When it dies, is the level out of sight?

The steps identified by @1911, taken one at a time (filter, pump, tank) are (easy and cheap, a little harder and $, and more challenging and $)

My battery was running pretty low so I just changed it out and it wants to start but it won't now....However, I don't think I'm getting fuel into my carb now after changing my fuel filter also....maybe a line is clogged? (didn't see fuel in window) I think the timing should be good enough to at least start it...but maybe not...

Here is a quick video I shot of it trying to start, maybe it will help:

 

[thebigredrocker]

If you had a bunch of crap in your fuel filter(there's likely more to come) so you may need to have a peek inside your fuel tank. Pull the sender and use an iPhone camera to snap some pics. Probably not what you are wanting to hear. You may need to pull your tank, clean it and seal it. Blow the lines out good. Also may need to clean the carb out.

 

[AlexMoore91]

If you had a bunch of crap in your fuel filter(there's likely more to come) so you may need to have a peek inside your fuel tank. Pull the sender and use an iPhone camera to snap some pics. Probably not what you are wanting to hear. You may need to pull your tank, clean it and seal it. Blow the lines out good. Also may need to clean the carb out.

Thanks for the tip...I guess I'm putting off the inevitable. I actually changed out the fuel filter and blew some air in the lines (per recommendation of pngunme) and it started up and it's running pretty good for now. Ran it for about 30 minutes last night with no problems, and it cranked right up this morning first try. I guess i'll prob need to clean the tank if I find that this new Fuel filter has a bunch of junk in it after some time.

Thanks for all the help guys! I have a few routes to go to make it run better...Adjust advanced timing, clean the carb, and clean the tank seems like the next few steps to preventing the same problem in the future.