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Timing Belt and Ignition Timing?

johfraser

Member
Joined
Sep 25, 2008
Location
San Francisco
Bought my ?81 240 DL B21F and a full set of green manuals in 1986 . Been doing all the maintenance and repairs myself so I?m not a newbie. However, It has been a few years since doing a timing belt replacement and now I?m confused about setting the timing.

I lined up all the timing marks and belt strips and the distributor rotor is pointing at the notch on the edge of the distributor. I have not moved the distributor. So, the engine started right up but the idle is very low and the timing light shows the spark way retarded. What have I missed?

The car had been running fine, smooth and torquey, with its AW70 and a recent California smog pass.
 
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Yours is retarded if you did not move the distributor.

However I'm assuming a block mounted dist and possibly a previous mechanic that moved stuff.

Rotate the dist to the advanced direction and see if you can bring the timing into spec.
Otherwise you will need to loosen the belt enough to slip the aux shaft pulley one notch sooner.

I would also advise to not operate the car until this is straightened out to prevent any damage from incorrect timing.

The aux shaft does not need to be timed, as long as the distributor can be moved into the needed position for correct spark timing.
You could also just pull the distributor up enough to slip the gear one tooth, but that is a lot bigger move than one tooth on the belt.
 
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B21F Redblock with block mounted variable reluctance distributor (4 metal fingers). No points, no computer.

Yes, I was coming to the same conclusion. I just don't understand why if the marks are lined up and the distributor was not moved. I must have gotten the marks wrong the last time. The car has run beautifully and always passed smog except once to replace the cat. Thanks for confirming.
 
Did you turn the engine over with the cap off? If so one of the clips for the cap may have caught on one of the 4 metal fingers and now it's out of phase. Can you post a pic of the distributor with the cap off @ TDC?

Here's a thread that may explain it better.

https://forums.turbobricks.com/showthread.php?t=307311

If the timing is off by just a little it could just be your old belt was stretched and the distributor was rotated to adjust it to spec.
 
It looks like the reluctor (thingie with 4 metal fingers) spun slightly on it's hub. Compare it to this pic. The locating notch should be aligned with one of the fingers.

http://hiperformanceautoservice.com/images/Reluctor1276617.JPG
Reluctor1276617.JPG


http://hiperformanceautoservice.com/images/johnfraserdistributor.jpg
johnfraserdistributor.jpg
 
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It certainly does look like that. That creates a problem with the spark having to jump quite a ways from the rotor tip to the terminal inside the cap.
 
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