FJ40 45 2F very weak

[efjayfourty]

Hi guys, first of all I wanna introduce myself, cause I didn't do a lot postings yet on this forum...
I am from Germany, proud owner of 3 Cruisers (FJ40, FJ45 PU, HJ45 camper)
I did a lot of travels with my 40 since 2010, across europe, Nothern Africa, the middle east and scandinavia. Actually this car I got from my father, who bought it new in 1978
From time to time, I do restaurations of 40 series and always look for new projects... Got the cruiser virus since I was a little boy!
My next travel rig's gonna be the HJ, which i'd like to convert into a FJ45 with a 3FE, but that's another story...
My question, and to come to the point is, if anyone of you guys has the mysteric issue about the missing power of the 2F ?
I need to say, that I have already checked out every, really erverything that might be causing trouble or tanking power in any way and what could be recognized with -I guess- more than just a little knowlegde of how this simple machine should be working properly...
compression, Carb (complete overhauled with love and patience), ignition, sparkplugs, distributor...
Everything is working great and the Engine runs like a swissmade stiching machine, You know what I mean...
All Compatments in the drivetrain are original and also the tires have the same size as factory build (7.50-16) I know from many people, who had 2F experiences in former times, that they were running like hell and pulling as a bull. I mean, the touque stll isn't too bad at all, but the performace is missing estimated 30 HP, maybe more!
And nowadys, I'm not the only one with this issue... But here in Kraut-country, people aren't very used to the lovely petrol Engines and that's why I don't find any decent information about this. Most of the owners here, they just drive to meetings with their FJ, about twice a year and they don't mind, if there are 30 HP more or less... But I want to find out the reason for this, whatever it may take DD
So if there's anyone of you who has or had the same problem, I'm very thankful for every idea or comment...
Additionally I need to mention that my FJ45 has just about 60tkm and it's like new, never used under hard conditions... the 40 has worked quite a lot in it's life, but both feel exactly the same about the performance, as well as a 40 of a friend of mine, who did a complete rebuild of the entire Engine...
All in all it seems like a real mistery...
And of course, I tried the question function here on this site, but couldn't find what i'm looing for...
Thanks to all, best regards, Felix

 

[Solace in Solitude]

Welcome Felix!!

Does your 40 have vacuum hoses ? For instance, from the carb to a vacuum advance module on your distributor?

Are there any open vacuum ports?

A vacuum leak robs your engine of horsepower.

I spent quite a bit of time trying to find a vacuum leak on my ‘78. Finally realized the distributor vacuum advance was leaking.

Since the vacuum advance module is no longer available, my choices were: 1. Replace the module with a used module; 2. Try to seal it and worry about it failing again; 3. Replace the distributor, with a new distributor that has a new vacuum advance module.

I went with #3 and installed a Davis Unified Ignition (DUI), specific to the FJ40. The DUI replaced the distributor, the coil, the igniter and negated the need for the Yazuki resistor wire that us spliced into the fat black-yellow wire.

If the vacuum advance is your problem, there are other options... like trollhole (MUDmember @Trollhole) distributors.

If your problem isn’t the vacuum advance leaking, I would still bet you have a vacuum leak somewhere... look for open vacuum ports, cracked vacuum hoses, leaking brake booster, leaking around the intake manifold, leaking under the carb, etc.

Once I replaced my distributor, I found I had more horsepower than ever!!

Good luck!!

Edit: Vacuum 101 - Land Cruiser Tech from IH8MUD.com

 

[efjayfourty]

@Solace in Solitude

Thanks for your comment! Yes I checked also if there's any leaking spot, and replaced the only vacuum hose my 40 has got, already 2 times, but that's obviously not the issue... Also I sprayed brake cleaner on top of the intake and all round the carb, while the engine was idling. No reaction... so it's fine. the vacuum advance module is holding up (I checked it with my mouth and a hose for about 20 seconds)

Also the coil (also replaced by new) gets enough voltage. That was my latest idea, but I double checked it as well as all the other things that could have a logical reason...

I mean, I didn't try a new distributor yet, but the one in my 45 is as good as new and as I said, this car has exactly the same problem...

Also the secondary diaphragm isn't leaking anyhow, I took many closer looks to it and tried several ones, that I had in stock...

I didn't mention, that I even bought one of these chinese made aftermarket carbs, of wich I didn't have much expectations, but it wasn't too bad I have to say... anyway, it dind't help at all, the performance was even less

I also checked the fuel tubes, they're all free.

And I tried 2 different NEW fuelpumps... no difference!

Compression: every cylinder higher than 10 bars!

What more can I tell you...

Thanks again for any ideas and suggestions !

 

[S4Cruiser]

Brakes dragging??

 

[efjayfourty]

@ S4Cruiser:

not at all...

 

[Solace in Solitude]

1. Plugs clean and properly gapped? @FJ40Jim recommended: Denso W14EXR-U spark plugs. They are hot plugs and coax the best performance out of the 2F engine. IIRC Jim suggested gapping the Plugs at .031”... with my dissy change to DUI, I now gap them at .055”.
2. Idle set to 650 rpm?
3. Timing set to 7 degrees BTDC?
4. Valves adjusted properly? .008” intake and .014” exhaust.
5. Fuel-air mixture set properly. Good info here —> Carb Works Great!
6. When were your carburetors last rebuilt? They may need rebuilding and tuning. @Pin_Head has great videos on YouTube, if you want to rebuild them yourself. If not, @FJ40Jim and @65swb45 are the rebuild experts on MUD.
   
7. Do you still run leaded fuel in GE? Or, unleaded now? What octane?
8. Did either of these two trucks run good before, or always poorly? What changed?
9. My dissy vacuum module was still working... like you tested your’s... that’s why it took so long to figure out that my vacuum loss was the dissy vac advance module. I’d check very carefully to be sure yours doesn’t have a vac leak.

The 2F engine will run forever... but, everything has to be properly adjusted in order to get the best possible performance.

Good luck!!

 

[Michael B]

Hi Felix ,
Welcome to the forum! I have a suggestion, try not driving your Porsche for a week and see if the both LC's will develop more power.

 

[Solace in Solitude]

Hi Felix ,
Welcome to the forum! I have a suggestion, try not driving your Porsche for a week and see if the both LC's will develop more power.

I hadn’t thought of that!!

Stay off the autobahn... you will feel you are going faster.

 

[65swb45]

It would be interesting to know if the linkage from the gas pedal to the carb is even giving you full throttle?

 

[efjayfourty]

@ pngunme:
It seems, that I really need to take another look at the vacuum hose these days...

Of course we have unfortunately just unleaded fuel remainig in germany... octane: 95

I fixed the carb already about 8 years ago, but the truck behaves exactly the same, ever since... before rebuilding it, the perfomance was just the same... And there were very old ignition cables and cheap Bosch-sparkplugs and the vacuum hose to the distributor was missing, the timing wasn't set on 7 deg, and so on, but it was NOT REALLY running worse than after renewing all of that crab

I carefully adjusted everything as shown in the manual, as well as you wrote it here. Beside this, I want to mention, that I even heard peolpe telling from former times, that it wasn't an issue at all how the 2F was tuned up. It always had power, just if the tuning was not good, the truck got less milage, but that's it... However, this isn't a reliable statement, but I heard it not only from one driver...

And about your point 8 : Yes, my 40 was definitly running much faster in its first life... because it is a heritage of my father, who bought it new, we have a very good comparison. He can tell, that this truck was running about 95 mph, maybe more! Now I can barely "torture" it up to 80mph, not more... But I have to say that it doesn't matter if this is with or without load (about 0.7 tons difference!) and in the second gear I even get it up to 40 mph, even going uphill with load insinde... It's just that it doesn't have the full range of performance that you can measure by the max speed and the acceleration is not what it should be.

@Michael B: Good idea, but the fastest car I have ,is a volvo 240 estate

@65swb45 : It gets full thottle. I checked that on both FJs...

One thing I forgot to say is that the carb develops air bubbles in the float chamber, when the engine is running high rpm (over 3000) And the float level goes down for a second when the throttle gets opened quickly... Tested in parked position but I guess under weight it could be worse, what would mean that the carb doesn't get enough fuel. But as I said before, I tried 2 new fuelpumps and 3 carbs (1 aftermarket, 2 originals) all the same...
I don't know if the bubbles are normal, but usually they shouldn't appear, I think !?!

Thanks again, CU

 

[Solace in Solitude]

Felix...

I have read of MUDders who drive 80mph... but never of those who drive these old trucks at 95mph.

At first, I thought you misspoke and that you meant 80kph and 95kph. But, you were explicit and 95kph would equate to about 60mph anyway.

I would never drive my 40 at 80mph... it’s just too hard on it at that speed. The rpms would be over 3600 and it would really “torture” it.

But, from my memories of the autobahn, I would hate to try to drive a 4x series, with all the high performance vehicles flying by!!

Plus, it’s a moving “box”... with poor aerodynamics, it could easily move from a “box” to a “coffin” at that speed.

If you can “torture” it to 80mph, I would be very happy!!

If you really want to try to bring them back to the 95mph you remember... start with dry and wet compression tests.

BE SURE you test with the throttle plate wide open and record all the results. These instructions explain the procedure —> Engine Compression Test Instructions - You Fix Cars.com - YouFixCars.com.

If the compression tests indicate problems, consider doing a leak down test, to more specifically determine the cause of low compression.

I have a ‘78 FJ40 too... it’s 40 years old... I couldn’t run nearly as fast and far, at 40 years of age, as I could when I was “new”... and I never ran on the autobahn.

I suspect the obvious... it’s an old truck and is tired, from running at high speed for so many years.

My 2F engine was rebuilt about three years ago and I drive it for enjoyment, not for speed... rarely at 70mph... mainly at 60mph. Not because it won’t go faster, but because I just feel anything over 3200rpm is too hard on the old girl.

I would compression test your’s, to see if there are issues that should be addressed... address them, as needed, and enjoy driving slower.

 

[Michael Hanson]

Hi, 85mph ,with high rpms will kill this motor pretty quick. My 2 cents. Mike

 

[snaggletto]

My '76 had a catalytic converter installed in the exhaust system. This got clogged and really choked everything down. Check for free flowing exhaust also.

 

[efjayfourty]

... okokok... OF COURSE I would never drive it so fast ! it's just for a test. And to give a picture of what is missing... Because if I just tell you that the acceleration isn't good any more, this wouldn't be represenable at all... But if I can give numbers, it's easy to understand - I think we don't need to discuss the way of treating an old machine...
And you guys can calm down, I'm mostly (like 9 of 10 times) riding it about 55mph are you satisfied now?

@Solace in Solitude:
Thanks for the compression link, I already had that on my to do list for a long time, but since I got the 45 wich runs even a bit smoother than my 40, I didn't di it because I'd bet my head on it, that it's absolutely fine, but of course I'll try to be sure and because there aren't much more things to check any more.

All in all I don't want a racing Cruiser, that's for sure, but 40 years or not, it's just a mystery that an engine looses such an amount of power without any reason (like it seems until now) I don't exaggerate, when I say that nowadays many 2Fs feel like driving a BJ42... To give another picture of what I'm talking about... It's the same with nearly all of them, and I did many comparisons on meetings or with cars from some friends. The thing is, they don't use their FJs like I do. I'm more or less the only "freak" in germany who travels around the world with a 2F engine. maybe you don't know, but about 90 percent of german cruiser enthusiasts prefer the Diesel engines... especeally when it comes to the old series...
So here's not a huge amount of experience and knowledge about the 2F or F existing... sad to say but it's true. And those who own one, they drive it extremly rare and of course, that's why they are fine with what it is. But I really use and love my FJs since I ve got a driving licence and I just want to enjoy it as much as it can be...
Once I drove an FJ40 that had the power that I am dreaming of, it was all original, the tuning was NOT the best, but that rig was just rocking! The only thing is, nobody knew, wich diffs it had got, but I guess it must have been the long ones (3,7) because it was in Iran and there they just have FJ series, so it should be all the same... And also one FJ75 (original 3F carb version) was really impressing me and that should be possible with the 2F as well...

Thanks to all again

 

[thebigredrocker]

I’ve read a number of posts where an object blocks the fuel pickup in the tank. If you pull the sender, an iPhone can get some good pictures of the tank.

Have you replaced your fuel hard lines and soft lines? Could a section of fuel line have just enough restriction on fuel flow.

Also, wonder if your tank venting is blocked?

Would be interesting to set up a small camera on the sight glass while you drive it.

 

[efjayfourty]

@thebigredrocker
...I also managed to put the feeding fuelhose into a 2liter fuel filled water bottle beside the engine, to let it pump from there instead of the tank. To avoid the issues, that you mentioned. And I did a testride with this installation, no effect... so also the tank venting is working fine.

I think I will again concentrate on the comprehensive compresion test and the vac. advance mod. and hope, I'll find anything, I didn't recognize so far... and yes, additionally i need to mount a little camera for checking the float level...

thanks