73 F engine tuneup, timing and compression. (1 Viewer)

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I've spent a couple hours searching for an answer to my question. I hate to ask (because I'm sure it's already been answered), but I can't find the answer, so here goes.

#1. I'm attempting to set the timing on my '73 F engine. My flywheel has the metal ball, but no other timing marks. I understand that the timing needs to be set to 7 degrees BTDC, at 630rpm.
Here's my question.
Does the metal ball represent TDC, or does it represent 7 degrees BTDC?
I'm assuming that IF it represents TDC, I need to adjust my timing light to 7 degrees advanced, and then rotate the distributer until the flywheel ball lines up to the timing pointer.
Yes?

#2. The cylinder compression numbers are: 140, 150, 140, 150, 165, 127 .
Once I get the timing set, I'll move on to adjusting the valves. The exhaust is currently pretty black, and it definitely smells strong. The motor also feels like it extremely week. The spark plugs look black. They're not oily, but seem to have a lot of carbon buildup fouling? I originally thought it might be bad rings, but the compression numbers look pretty good. Do you think lifters/valves could cause these issues?
Thoughts?
Thank you for your help.

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So with your timing light strobing at 0, you can turn your dissy until it strobes on the bb. Even though your light reads 0°, you are now actually at 7° Btdc.

If you want to try FJ40Jim’s recommendation to cap the 73 retarding dissy vac lines and go with 10°. Toggle your light to 3° advance and once again find your bb. Now you’ll be at 7+3=10°.
 
I remember a time when a 79 fj40 would back fire I still own. I tried resetting the timing and changed the plugs. Verified the firing order and checked the spark lug wires and still could not figure out why. Carb had issues but still did not think that would cause this issue. I changed the oil and the backfiring disappeared. I inspected the used oil and sure enough it had a faint smell of gas.

All I can add is the flywheel has to rotate twice to get one cycle of opening and closing all the intake/exhaust valves. And the answer is yes if all is working correctly, no vacuum leaks and all spark plugs are firing.
Inspect the rod that goes down to the lifter on the one that has low compression. Or maybe will improve when you adjust the valves. After adjusting the valves and the compression does not improve squirt oil through the spark plug hole and retest for compression.
Clean your spark plugs with a wire brush and verify the gap.
I recommend getting a factory manual if you have not already done.
After you are done tweaking the engine and it still feels weak, try disconnecting a spark plug wire and see if the engine starts shaking if it does, turn off engine and reconnect it move on to the next one. Sometimes the plug can be loose or mismatched. And sometimes just reseating them helps. Try both ends.
Also check your points. Or better yet replace them. Make sure it's not shorting out or that the points have a good connection. It's a fact, the electronic ignition system has a stonger spark.
Once you get these engine running correctly they are very dependable and easy to start.
 
The bb is 7° btdc. The line after it is tdc. The OEM 73 dissy is a vacuum retarding type. I’ve read it’s best to cap the vac line to it and set timing to 10° btdc.

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@thebigredrocker and @fjwagon
Thanks for the great information. In your picture, above, is your timing pin showing approximately 10 degrees BTDC? That's approximately where I set mine. It's still lacking a lot of of power. It feels WEAK. I've installed a Trollhole carb, and electronic dizzy, replaced the spark plugs . . .. I'll grab a set of wires, just to rule out the possibility that they're contributing to the issues. I'm hopping the valve adjustment will help with the lack of power, and strong exhaust/black exhaust.
 
That picture was taken merely to show the TDC line and the bb. The flywheel is rotating clockwise, so the bb(7°) comes first and then the line(0° TDC) In theory if I set the dissy to fire as pictured it would be 3°-4° before TDC.

BB in bottom of window or past the pin would be about 10°.

I’d recommend taking vacuum readings during this process. Engine needs to be well warmed up. Keep an eye on what happens to vac when you change a variable.
 
I know this may be a stupid question but I am still cutting my teeth on alot of this stuff. I am trying to check the timing on my FJ40 as she is running a little hot.

Question is how do I rotate the flywheel to get the bb in the window?
 
Krondor and Steamer, thank you. I'm going to get to work on this when I get home.

Steamer, as an aside, I appreciate all the posts you have done on overheating issues on different threads. I have learned many things from those posts. I would be completely lost without the help.
 
Steamer, as an aside, I appreciate all the posts you have done on overheating issues on different threads. I have learned many things from those posts. I would be completely lost without the help.

You’re welcome. Glad it helped. My 40 experience & knowledge is limited and I’m mostly learning from others here. I did get quite good at flushing though because of the unusual abuse my rig suffered from the PO and also form my mistakes. Flushing is the best thing I do. lol.
 
Super simple way is put rig is 4th gear, remove dissy cap and roll the rig until flywheel mark appears and rotor button is where the #1 spark plug wire resides on the cap.

Another way is use a remote starter and just bump it until you reach TDC. Multiple bumps are sometimes needed. Screw driver works if you don’t have a remote trigger.
 
MadMace,

I used a remote starter (best $20 I ever spent), removed the coil so it wouldn't start and bumped the trigger until I saw the timing mark and BB. Then, I turned the fan while pressing on the belt (so it didn't slip) to get the BB aligned to the other mark. After that, I put a spot of white paint on the BB so when I timed it, it was really easy to see.

I'm also in San Antonio and just purchased my first rust bucket (1972) a few months ago. What part of town you in? I'm on the NW side. Are you in the Alamo City Land Cruiser Club? I follow them on the Facebook group but haven't yet met up with that group.

Good luck!

https://www.amazon.com/gp/product/B000EVU8MK/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
 
I used the 4th gear, rocking it back-and-forth trick. Just like thebigredrocker said above, super easy.

So I think my timing is off and, if that is correct, is likely causing Marion to run too hot. Please see the pictures below and tell me if my assumption is correct.

The first picture shows the timing ball aligned with the pointer. Second picture shows the dizzy with the cap on to show where the point for "1" is. In the 3rd picture, I edited in a line to show where the rotor would need to be to be on the "1" point. You can see the rotor is rotated clockwise from point "1" when the timing ball is aligned with the pointer. The final picture shows where I am on the flywheel when the rotor is on the point of "1". This position is clockwise (or to the right) of the BB.

Am I correct that my timing is off? I am thinking that the ignition timing is too far advanced.

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DMully,

I am in NE SA. North of the 281 at TPC Parkway. I'd love to get together and admire your rig. I am sure we can be a great resource to each other.

Shoot me a PM and we'll swap info and start talking about a time to get together.

No, I am not a member of the Alamo City Land Cruiser Club--I need to be though.
 
View attachment 1718270
Am I understanding correctly, #1 is getting spark when the bb is out of view?

Yes, #1 is getting spark when the bb is out of view. I put a red circle around the yellow dot where I suspect the BB is when #1 is getting spark (I am assuming that spark happens when the rotor passes over the point). It is possible that it is even farther than indicated, but not by much.

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Am I correct that my timing is off? I am thinking that the ignition timing is too far advanced.

Looks like it. Can you rotate the dizzy clockwise to retard it without the engine dying?
 

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