Timing mark

[Ed-datsun521]

Need help I can't find one can anyone help me find it I have a 1971 521 l16 motor

I need the small arrow that bolts up can anyone help me ?

[datzenmike]

This is General discussion you want the classifieds at top of page... http://community.ratsun.net/classifieds/category/4-engine/?sort_key=date_added&sort_order=desc

[DanielC]

Here is a picture of the 521 L-16 timing pointer.

It is just a piece of metal, with a hole to bolt it to the timing chain cover, and a pointer.

Make one.

[tr8er]

Can of Pepsi, kitchen scissors, hole punch.

[Ed-datsun521]

I think I need the saw looking timing mark thing does anyone have a picture of this or dimensions ?

[HRH]

Go to any wrecking yard for just about any L motor, you'll find one.  Or, pull out the number one spark plug and put in a small screwdriver then turn the crank with a socket.  Hold the screwdriver so it doesn't jam in the hole.  When it reaches the top (TDC) you are at the 0 degree mark for either the intake or exhaust stroke.  If the crank keyway is pointing up, that's the correct way to find TDC without a point.  Then you can make any pointer you want off the reference mark in the crank pulley.

[datzenmike]

Z20/22 and Z24s have the saw tooth timing scale also and the 'same' as for the L20B side near the alternator.

 

Actually there is a slight difference in the scale but if you look the zero is in the same place on all. Just clockwise of the mounting bolt.

 

L20B ('79)

 

 

 

Z24

 

( lol Went out and took these pictures 5 min ago. L20B in driveway, Z24 in back yard and L20B timing cover in the stash pile. -9C / 16F friggin cold not used to it. Big Dog called me a pussy!!!)

[Ed-datsun521]

Mike that looks perfect I could work it out from there I'm trying to set the timing on my truck after I just changed the head gasket I lines up the engine at tdc and the head also just trying to get the timing set perfect with out the marks is hard and I know I need this saw scale because my crankshaft pulley only has one mark and also my l16 has a w53 head so it's kinda been peiced together from different motors?!?

[datzenmike]

Earlier motors had a single pointer with several notches on the pulley. The first notch t line up would be 20 BTDC and is confusing (not the best way to do it IMHO)

Later motors had a single notch on the pulley and a legible scale to read the numbers.

[Ed-datsun521]

i seen to have the one with the single notch on the pulley and im going to try to make this"saw " timing mark thing ,

the truck starts up fine and idles fine i took it for a test drive ysterday after i was done and when i got up to speed it just bogged out pressed the gas and i would not or accelerate any longer it also felt kinda "slow " from take off could this be because of the timing or because somehow i clogged up the carburator

[Ed-datsun521]

does anyone have any idea what could cause this ?

[datzenmike]

It could be. Just retard the timing slightly by turning the dizzy counter clockwise. Leave the adjustment screw snug enough to allow you to twist the dizzy. Drive it and see if improved. If worse try advancing clockwise.

If there is a pinging sound under load you should retard just enough to get rid of it.

[banzai510(hainz)]

the sawtooth timming plate should match the mark on the pulley. Just to let you know there are left hand and right side sawtooth timming plates.

 

as mike suggested try turing the dizzy retard or adv.  key is if you installed the oil pump correctly. if you changed just the head and didnt drop the pump then just move the dizzy.

 

at TDC just get a ink pen mark on front cover so when you put the light on there the notch as it lights up with the timming gun should be left of your ink pen mark and this will indicat BTDC when it fires.

[Ed-datsun521]

I think I'm going to turn the engine to tdc mark it on the block and go off that for now I hope that work well enough. Yesterday is when I took the truck out for a drive I'm going to try today after I adjusted the truck a little bit

[banzai510(hainz)]

the crank notch will be to the left of the inkpen mark as the light if firing. just to be clear.

 

hope you had the cam set up(timmed) correctly but a tooth off isnt going to be too noticeable I think.

[Ed-datsun521]

yeah i had everything lined up just like on the vids on you tube  triple checked before i took off the cam gear

i hope its just a timing a lil off on the distribuitor

[ggzilla]

Once you determine 10° BTDC, actually check the spark (don't just rely on distributor markings).

 

With engine turned to the correct timing mark:

1. pull coil wire from cap. Lay atop the engine or strut tower, with the metal lead 1/4 inch from bare metal

2. turn Key to IGN (do not start engine)

3. Loosen the distributor hold down bolt slightly. Be careful not to rotate the distributor.

4. Rotate housing clockwise slightly until points appear closed

5. Rotate housing anti-clockwise -- slowly -- until a spark appears at the coil wire

6. Tighten distributor hold-down bolt

7. Replace cap (ensure rotor still points to #1 or #4)

[Ed-datsun521]

Should I set my truck to zero or 10 btdc ? I don't think I am running the smog anymore I don't see it hooked up

[ggzilla]

Smog has nothing to do with it. Zero is too little advance, lowers power, and makes engine run hotter.

 

Set the timing to stock spec is safe. Then you can time it by ear for more advance. but in no case should you let it ping. Too much advance will also reduce high rpm power. Set it to the most advance that works. Better yet if you have an advance timing light you can use that to set total advance at 5000 rpm which is more accurate than setting initial advance.

 

Datsun distributors have a 4° tolerance, so an initial advance that works on one engine may destroy another one.

[ggzilla]

To be clear, the pointer should read Zero at TDC (when the pulley marks line up).

 

Then when you set ignition timing, it should be set to spec to start with. It'll run good there.

[Ed-datsun521]

So I set it to zero or ten btdc

[Ed-datsun521]

Ok so I checked the light and it lines up with zero at 33. Degrees so I need to adjust the distributior 43* degrees ? Sorry new to timing

[ggzilla]

Zero or 10? Zero at 33? I don't know what you are saying.

 

43° is way too much in any case.

[Ed-datsun521]

Ok so in put the timing light on and turn on. The truck and now that. Is at idle I adjusted the timing light so that the mark lines up with 0degrees my ligth says it took 33 degrees advance to get it there so do I need to adjust my distributor 23 degrees to get it to 10 degrees btdc ?

[Ed-datsun521]

Did I screw up my distributor when I put it back on ?