I can't drive 55 (1 Viewer)

[MatthewMcD]

They are designed to spin, it makes sure everything wears evenly on a flat tappet engine. Hopefully this picture illustrates WHY they spin:
View attachment 3744519
Note: This is exaggerated, you usually cannot see or feel the slight angle they put Into the camshaft.

Thank you, I love this forum! I have learned more about the science of cars here than anywhere else.

 

[fyton2v]

This is an interesting thread.

The motor sounds pretty darn good. I skimmed the thread but I've didn't get a sense of the responsiveness of your motor when you smash the accelerator at 2K+ RPMs. If you're having trouble gaining speed (50+ MPH) on any minor incline, that carburetor may be starving your engine. Even if your truck is stuck in 4H, it should still be capable of gaining speed until it explodes, which happens at 80mph I believe. My compression numbers are similar, and on 33s it's quite easy to get to 65+. I'm running the stock Aisan carburetor with 4.11 gears.

If I recall correctly, Cityracer sells a reproduction of the stock 2F carb for a reasonable price that people seem to like. You can likely search on that to find more info.

 

[Green Bean]

Side question, because today was the first time I've had the valve cover off. We noticed that when the engine is running the push rods spin. Some of them spin pretty fast. Is this normal? What causes the spin?

BTW: In addition to what others have said, I've seen where some folks will, for diagnostic purposes, apply a vertical mark on each push rod with a paint pen. Then start the motor to watch to make sure that each rod is rotating as it should. I believe if there is no rotation, it could indicate a problem lifter or worn cam lobe.

 

[MatthewMcD]

I'm not sure when they added catalytic converters to FJ40s but if its an original exhaust system (I highly doubt that it is) then it could be plugged up.

From the video it sounds like the timing could be a bit late/lazy sounding. Set the points and then loosen the bottom bolt on the dizzy and try and turning it clockwise (I believe) to advance the timing a bit. I like to use a timing gun but if you know an old guy they should be able to set the timing by ear/feel.
Edit: if you can take the vacuum line off for the dizzy and suck on the end of the line the engine should rev up a bit at idle.

No catalytic converter, just a single muffler.

The timing is currently at 7*, I'll get in and recheck the points and timing again now that I know the valves are right.

Pulling a vacuum on the line to the distributor does advance the timing a bit. I am questioning the manual advance. When I turn the rotor by hand it does not move that far. Like maybe from 1-2 on a clock, not a quarter turn. How far should it turn by hand?

 

[charliemeyer007]

In the warm weather I can crank up the timing where it just goes out of the window. I have a straight mechanical delco dizzy.

Did you verify 4.1 something gears.

 

[pb4ugo]

No catalytic converter, just a single muffler.

The timing is currently at 7*, I'll get in and recheck the points and timing again now that I know the valves are right.

Pulling a vacuum on the line to the distributor does advance the timing a bit. I am questioning the manual advance. When I turn the rotor by hand it does not move that far. Like maybe from 1-2 on a clock, not a quarter turn. How far should it turn by hand?

Your mechanical advance descripton sounds correct.

 

[MatthewMcD]

In the warm weather I can crank up the timing where it just goes out of the window. I have a straight mechanical delco dizzy.

Did you verify 4.1 something gears.

I think I did. With one rear tire off the ground I got 2 1/8 turns of the drive shaft for one rotation of the wheel.

 

[RevISK]

Was there a Mandela effect in post #89?

Probably a Mandala effect

 

[Grayscale]

Slipping clutch?

 

[Pighead]

Slipping clutch?

Would probably be evident in other gears too?

 

[45Dougal]

I think you already set the points?
Dizzy shaft bearings aren't so worn as to compromise the gap?
Is the Condenser known to be good? - can have a big impact.
Tried removing your air filter, or partly restricting it?
Tried opening the fuel cap?
Try getting to max speed, and then dip the clutch and let it idle for a few seconds to allow the float bowl to fill up, and then resume driving?
Even though the brakes feel free, it's easy to check if they're hot when you stop - including the handbrake.
The coil isn't having a meltdown is it?

 

[Pighead]

I’m at 11* with my stupid Weber and it’s as close to a racetruck as I care to get.

Why? What happens at 12*? I thought you wanted to go faster...
Lots of people say that 17* is a good spot to start. I'm running 30* right now.
The old-school way of timing was to advance until it pinged under load. Still works.

 

[Skreddy]

How fresh is your gas? I’ve had 6 month old gas severely rib performance.

I’m with others that the carb is probably the choke point.

 

[MatthewMcD]

Slipping clutch?

I don't think so. It feels very solid. Lots of torque when I "hold it" on a hill (like my driveway).

 

[MatthewMcD]

How fresh is your gas? I’ve had 6 month old gas severely rib performance.

I’m with others that the carb is probably the choke point.

I put in 1/2 a tank last Thursday. I have used a lot of it now that I am driving it more. I'll probably top it up in the next day or so.

It's not running rough, like I have felt with other bad gas situations, it actually runs great, just no top end power.

 

[MatthewMcD]

Why? What happens at 12*? I thought you wanted to go faster...
Lots of people say that 17* is a good spot to start. I'm running 30* right now.
The old-school way of timing was to advance until it pinged under load. Still works.

30* !

 

[MatthewMcD]

I think you already set the points?
Dizzy shaft bearings aren't so worn as to compromise the gap?
Is the Condenser known to be good? - can have a big impact.
Tried removing your air filter, or partly restricting it?
Tried opening the fuel cap?
Try getting to max speed, and then dip the clutch and let it idle for a few seconds to allow the float bowl to fill up, and then resume driving?
Even though the brakes feel free, it's easy to check if they're hot when you stop - including the handbrake.
The coil isn't having a meltdown is it?

Not sure about the shaft bearings.
Condenser is brand new.
Haven't tried anything with the air filter.
Gas cap? No.

I'll check the brakes next.

Coil is new as is the resistor. Do you mean hot to the touch?

I'll try the "dip test" next time I am out.

 

[Pighead]

30* !

Yes, but. That's after a fair amount of engine work, you're probably not ready for that much advance yet, but it is possible. For years, before I got the fancy timing light, I timed by manifold vacuum (still do, sorta) and when I finally did get the digital timing light I found I was ar 22*.

 

[zerotreedelta]

Side thread - what's your total advance running that much base?

Yes, but. That's after a fair amount of engine work, you're probably not ready for that much advance yet, but it is possible. For years, before I got the fancy timing light, I timed by manifold vacuum (still do, sorta) and when I finally did get the digital timing light I found I was ar 22*.

 

[Pighead]

Side thread - what's your total advance running that much base?

I don't know. I was running the Big Cap dizzy for a long time, but I had switched springs and the advance mechanism. I just put in this small cap points dizzy with the pertronix.
So, it might take a few days to dial in this dizzy and I don't know exactly how to measure total advance...