l20 timing problem

[Just Joel]

Ok, I have rebuilt this motor from the bottom up being vary carful to follow both the advice of this forum and the FSM as I go. Last night I attempted to install the matchbox distributor when I noticed something odd. While the motor is at TDC the distributor rotor points between 1 and 3 not at the number one cylinder as it should (at least I think)

 

 

 

The cam is at 10 and 2 as it should be and the distributor drive is at 11:28 with the small side forward at TDC

 

 

 

I need help interpreting this data and solving my problem if there is one.

 

Thanks

Joel

[josh_t]

dumb question, but it does happen, do you have the 1st cylinder on its compression stroke?

[datzenmike]

All you need to get it running, is the rotor pointing to any plug wire on the cap. So drop the oil pump and it's drive spindle. Turn the drive spindle a couple of teeth clockwise as seen from above so that instead of 11:28 it will now be, say, 11:35. Install everything loosely and see if the dizzy now points near a plug wire on the cap above it. If not try again, this is not an exact science. When you do get the rotor pointing at any plug wire on the cap THIS now becomes your #1 plug wire. Move the #1 wire to it and move all the others around (1,3,4,2) firing order. Now tighten the oil pump in place properly, set the timing.

[josh_t]

All you need to get it running, is the rotor pointing to any plug wire on the cap. So drop the oil pump and it's drive spindle. Turn the drive spindle a couple of teeth clockwise as seen from above so that instead of 11:28 it will now be, say, 11:35. Install everything loosely and see if the dizzy now points near a plug wire on the cap above it. If not try again, this is not an exact science. When you do get the rotor pointing at any plug wire on the cap THIS now becomes your #1 plug wire. Move the #1 wire to it and move all the others around (1,3,4,2) firing order. Now tighten the oil pump in place properly, set the timing.

i never thought of that. it makes perfect sense. why didnt you tell me that when i was diagnosing my misfire?

[DanielC]

Is this the distributer that came with the engine from the factory?

On this page of my thread, I detailed how I timed a matchbox distributer on a L-16 engine.

http://community.ratsun.net/topic/30606-my-ratsun-datsun-521/page__st__20

[Just Joel]

All you need to get it running, is the rotor pointing to any plug wire on the cap. So drop the oil pump and it's drive spindle. Turn the drive spindle a couple of teeth clockwise as seen from above so that instead of 11:28 it will now be, say, 11:35. Install everything loosely and see if the dizzy now points near a plug wire on the cap above it. If not try again, this is not an exact science. When you do get the rotor pointing at any plug wire on the cap THIS now becomes your #1 plug wire. Move the #1 wire to it and move all the others around (1,3,4,2) firing order. Now tighten the oil pump in place properly, set the timing.

Really? I’ve read the instructions and it always seems that if the distributor drive is at 11:28 your set. What could have thrown it off? I would rather start with a proper setup than compensate for past owners jerry rigging.

 

Thanks

Joel

[Just Joel]

Is this the distributer that came with the engine from the factory?

On this page of my thread, I detailed how I timed a matchbox distributer on a L-16 engine.

http://community.ratsun.net/topic/30606-my-ratsun-datsun-521/page__st__20

 

As far as I know, yes... This is an l20b from a 79 620 and I believe those cam equip with the matchbox dizzy.

 

Thanks

Joel

[DanielC]

The "11:28" standard works with the distributer that came with the engine. If you, or a previous owner puts an different distributer, you may have to deviate from the 11:28 position to get the distributer to line up properly with the rotor under a tower on the distributer cap, with the engine ready to fire.

Having a different distributer mount or pedestal can also change the "clocking" of the distributer.

You can try to find all the proper parts to make everything line up, with the drive spindle at 11:28, or you can just drop the oil pump, and with the engine at the proper position to fire, turn the spindle until the distributer lines up.

[Just Joel]

Well shit, I guess I'll be ordering another gasket on monday and dropping the pump (again). So where do I want to set up the first cylinder? TDC or at twelve degrees where it's timed?

 

Thanks

Joel

[DanielC]

I would set it up at about 12 degrees BTDC. This is to get it started. When it is running recheck the timing with a timing light.

The first time you drive it listen carefully for detonation, or "pinging" If it does, you must retard the timing a little.

[datzenmike]

I'd set the motor at TDC compression on the #1 cylinder, reset the spindle so that the rotor is under ANY plug wire on the cap. Make sure the distributor adjustment range is in the middle and NOT maxed out in one direction. I put my oil pump bolts in finger tight in case I had to drop it again and move the spindle a second or third time. (ended up more like eight times) I was excited and in a hurry and did it in the wrecking yard parking lot and the spindle fell out when trying to fit a matchbox dizzy. After five tries I just sat down and remembered Hainz's video. Another three tries to get the spindle right and fired right up and drove home.

 

Once you get the rotor set right don't forget to tighten the oil pump bolts.Now make the timing adjustment and enjoy. No one is going to see the dizzy isn't at 11:28.

[Just Joel]

How noticeable is the detonation sound? I've never experienced this...

 

Thanks

Joel

[Just Joel]

Also, after installing the pump for the last time (or so I thought) I regretted not making a priming rod out of an old distributor drive and priming the motor. Given the opportunity, should I consider this now or just rely on priming only the pump? This is the first start on a new motor. Also, should I be using break in oil or just standard oil for the first change?

 

Thanks

Joel

[josh_t]

How noticeable is the detonation sound? I've never experienced this...

 

Thanks

Joel

 

depends on how far you advance it into detonation. it will be pretty noticeable. i have seen it described as it sounding like someone is hitting metal with a ball peen hammer. and it does.

[datzenmike]

depends on how far you advance it into detonation. it will be pretty noticeable. i have seen it described as it sounding like someone is hitting metal with a ball peen hammer. and it does.

 

Half fill the oil filter, hold the throttle full open with the plugs out and the coil wire off so it won't try to start and crank the motor over. When the ignition is in the on position the low oil pressure light will be on. The oil light is turned on by a sensor set to less than 5-8 PSI. Crank for 10 seconds and let the key back to the on position immediately. If the light comes on right away give it 10 more seconds. If the light is out but comes back on in 3-5 seconds the oil system is primed. If you have the valve cover off you can see oil dripping off the cam lobes.

 

Do not ever us a 'break in' oil or any oil additives. You can however use a cheap bargain oil by the gallon for start-up and the first 20 miles or so and dump out and replace with your favorite brand and a new filter.

[Cameron.]

^ another way you can do it is by a drill down to the oilpump drive. a lot easier and dont have to worry about dry spinning your engine

[Just Joel]

Do not ever us a 'break in' oil or any oil additives. You can however use a cheap bargain oil by the gallon for start-up and the first 20 miles or so and dump out and replace with your favorite brand and a new filter.

 

Thanks, I bought a couple cases of chevron oil when it was on sale at costco the other day for all the changes up to five hundred miles so it sounds like I should be good to go. After that I plan to switch to synthetic.

 

Thanks

Joel

[Just Joel]

^ another way you can do it is by a drill down to the oilpump drive. a lot easier and dont have to worry about dry spinning your engine

 

This was what I was thinking...

 

Thanks

Hotel

[datzenmike]

If it was rebuilt it will have assembly lube on everything and a little oil goes a long way. I've pulled motors that haven't run in years and they still have a layer of oil on the rods and mains. Cranking isn't that hard on it compared to running with a load on it. Still it creeps me out to have little to no oil pressure on start-ups.

[DanielC]

"^ another way you can do it is by a drill down to the oilpump drive. a lot easier and dont have to worry about dry spinning your engine"

 

Cameron, you cannot drive the oil pump on an L series engine by putting a drill down to the oil pump drive. You can on most American V-8 engines.

 

On an L series engine, the gear that drives the oil pump and distributer is on the oil pump drive spindle. The gear does not come out with the distributer. To drive the oil pump, you have to take an old drive spindle, remove a roll pin, and press the gear off it. You them install the oil pump with the gear less spindle, and you can drive that with a drill.

[datzenmike]

Or remove the spindle and install the pump. Use a long screwdriver, (a cheap one with the handle removed ) or some round stock flattened at the end and drive with an electric drill. HRH did this I think.

[banzai510(hainz)]

Just Joel everything is CORRECT!!!!

 

The rotor pointed inbetween 1 and 3 is Cause you have a matchbox dizzy with the WRONG pedastal mount.

There were 2 mounts for the matchbox. Now you either didnt get a matching set. or you grab a dizzy by itself and put the wrong mount on.

 

if you have the other Matchbox dizzy mount you dont need to drop the oil pump. PS make sure the timming plate is center. so you have full movement.

 

the 11.28 is pretty much standard on putting a L motor together and if you put another matching dizzy with mount it should point right on a plug wire(sometime off 180 depending where you want you vac adv ,just move the plug wires and your done.

 

 

For priming the pump? lets not make this hard. Put oil in it and then maybe get a line and pour oil towards the front cover where the oil filter goes on. youll see the hole going towards the front.

 

My vid on olddatsun.com says this in the first part when Im looking at the spindal/dizzy set up.

[Just Joel]

Thanks hainz, the previous owner must have mated the mismatched mount and compensated for it as described in this thread.

 

I guess if I want it right, I need to find a mount. Anyone have an extra?

 

Thanks

Joel