66 FJ40 Ignition Timing

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1966 FJ40 Stock 6cylinder engine (basically) with stock large window 1 barrel carb.
Modification:
200 amp GM alternate
Distributor of unknown brand no markings, condenser mounted external to frame

After reading several posy I have tow questions:
1. Is the BB on the flywheel at TDC , or at 7 deg or something else
2. What is the best timing, I have read 14 degrees or set it on the BB.

My FJ has been run like crap ever since I rescued it and got it running, but I think I have solved the problem.
Problem: It would not run half way decent unless I had the choke half way out. it would barely idol with choke pushed all the way in.
Troubleshooting:
This sound like a vacuum leak but several time tracing, wiggling and spraying every hose and pipe no vacuum leaks found
Vacuum at intake manifold was 14" and steady
Vacuum at Vacuum Advance on distributor was 0 at idle and 5" at 1700 rpm and 2000 rpm
(not sure why I only have 5" at VA instead of 14? I did have a problem trying to Tee into the very small line leading to the VA)
Points set to .018 with feeler gauge ( had two broke dwell meter)
With timing set at 7 deg (+ 7 of BB) , Vacuum at VA was 0" and Manifold vacuum was at 14",idle was missing a little
Set RPM to 1700, timing moved to 15 (+7 ?) degree and engine was bucking and snorting, Vacuum at VA was 5" and Manifold vacuum was at 14"

Pulled choke half way out
RPM went to 2200, timing went to 21 (+7?) , engine smooth out with very little missing. Vacuum at VA was 5" and Manifold vacuum was at 14"
During the time the choke was half way out the timing mark remained stead at the flywheel pointer.
Although I do not know what the vacuum advance curve is, it appeared the advance was working and the distributor, although of unknow manufacture, was working properly.
So at this point I decided to focus my attention on my carburetor but before that I decided to remove my spark plugs and see what they would tell me.
They told me a lot, they were way the wrong plugs, very short threads about half the length of what they should be.

Looking at the thread in the cylinder head the were carboned up about half wat.
Cleaned threads and vacuumed head and installed new correct plugs
At this point I had about as much fun as I could handled so I just started the engine (which was a little cold) revved it a couple times and it sounded good (choke all the way end).
Tomorrow I will go back and check every thing, such as timing, remove test vacuum lines and take it for a drive.
 

Pighead

Stop calling it an FJ
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That's a lot to read. I gotta go back and do it again.
In the meantime. May we have pictures please?
 

65swb45

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1. Forget about checking the vac on the advancer port.
2. Relash the valves and retest vacuum at 14 degrees of base timing.
3. Close the point gap to .012 and retest vacuum at 14 degrees of base timing.
4. Report back.

Why? Because I have four decades of good hunches.😊
 
Joined
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1. Forget about checking the vac on the advancer port.
2. Relash the valves and retest vacuum at 14 degrees of base timing.
3. Close the point gap to .012 and retest vacuum at 14 degrees of base timing.
4. Report back.

Why? Because I have four decades of good hunches.😊
I am on my way to the shop, will do and report back this PM.
 

Pighead

Stop calling it an FJ
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After reading several posy I have tow questions:
1. Is the BB on the flywheel at TDC , or at 7 deg or something else
2. What is the best timing, I have read 14 degrees or set it on the BB.
Ok, let's knock off the easy questions first.
1. The BB is 7 degrees before top dead center.
There is a line at top dead center
B. The best timing is different for every LandCruiser. Start at the BB and advance timing to where yours runs best. Some go by ear, some by nose, some the vacuum gauge. Some advance to where it pings under load and then retard until it doesn't. I consult the entrails of a freshly slaughtered hog.
 
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Thank you, I have it right now at 7 degrees past the BB, and it seem to be running fie. Maybe it could be better but that is for another day
 

65swb45

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Translation: you haven’t adjusted your valves, and you don’t own a vacuum guage.
 
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IMG_20220318_110325 - Copy - Copy (2).jpg
IMG_20220318_110513.jpg
IMG_20220318_110513.jpg
 
Joined
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Photos, sorry for the fuzzies, of my un-branded distributor. There are no marking on it. I just ordered a set of points for it from O'Rilleys, there parts catalog showed a picture of the point and it looked the same as what is in my distributor. Will know tomorrow if they work.
Two items on this distributor that look non-standard
Condensor mounted on outside
Vacuum advance does not look stock and appears to be adjustable
Any ideas what it is.?
 

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