L18 which one do I have

[racerx]

Okay I've installed an L18 into my 71 Datsun. The engine was purchased from Ebay, Fliteline Engines, and they don't know what year. So I am scratching my head cuz their are 2 different timing and firing orders (1973 - 1974). I am assuming one is dual point. One timing is 12 BTDC and one is 5 BTDC. I am going to try 5 BTDC, any comments. I've pasted the link below regarding firing order and timing.

 

http://www.autozone.com/az/cds/en_us/0900823d/80/17/a3/1a/0900823d8017a31a/repairInfoPages.htm

[hang_510]

the firing order is always the same. position of #1 plug moved.

 

id say the 12* is a better start.

5* may be w/an auto in D or w/the lights on???

[datzenmike]

L18s were used on '74 710s, '73 610 and '73.5-'74 620s. The '73 620 timing was 5 degrees BTDC manual and automatic. The '74 620 was 12 BTDC manual and automatic. The '73 had dual points man and auto and the '74 had single points man and auto.

[J.C_620]

what is the best timing for a L20B with closed chambered A87 head? right now i am running at 12 degrees btdc but sometimes i move it to 15-20 depending if i am running highway or rual roads

[racerx]

On all of my cars I always try to max timing till it pings. Like my 75 Celica I think timing is like 8 but I am at about 12, I backed off a little bit since it pinged some. You don't want your car to ping cuz it will cause some damage in the long run. Just maximize it...before it pings.

[racerx]

BTw when you guys look at the picture from autozone, the website, under my orig. post. Do you guys see the 2 marks on the circle, does this mean this is how the rotor is supposed to line up.

 

 

RacerX

[hang_510]

id guess those marks are the clips to secure the cap.

the rotor would be @/on #1 for timing purposes.

[racerx]

Yep that's what I figure and just want to make sure cuz the rotor also lines up that way..I am now certain that my firing order is okay, just got o mess with my timing chain so its tight, where do you guys hold on to the timing chain, when you turn the crankshaft. On the video he said that some cams came with a "boss". I don't want to damage my cam....

 

I remember Hainz video and he said that the timing chain should be kept snug while making adjustment to TDC and maybe that's why mine is not exactly at 11.28 or 11.25 (ol book says 11.25). Although the timing mark is pointing at the biggest indentation of the pulley, which means O but I can also be a teeth off or something. I will look into this this weekend.

 

Thanks...

[datzenmike]

Once at TDC the chain is locked and the crank must not be turned or the tensioner will fall out. The cam can be turned for adjustment once the chain and sprocket is removed.

[banzai510(hainz)]

heres the boss with the 2 knob block looking things right in the center

 

most L16 cams DID NOT have these. and I jam a big screw driver threw the cam sprocket. Some loosen before removed from car

or lock the flywheel ect(to break the cam,crank bolt)

[banzai510(hainz)]

RacerX

when I talk about keep the chain tite when dialing it up to ZERO(clock wise) on crank is more on intial set up to make sure your cam is timmed up ans see where your dizzy spindal is.

One should do this to any motor esp if a used not running so you can tell right off the bat if the cam is off a tooth or the oil pump drive was installed wrong(uasually a previous owner)

If you go past zero ant turn it back to zero counter clock wise you just put the slack on the tight side of the chain guide.

 

 

If you do a head swap you diffenitely dont want to move anything once the head is OFF!!!!!!!!!!

 

 

If removing the head and front cover just get the crank.cam bolt loose and dial it up to zero and its not big deal if it moves a little and remove the head

[racerx]

Okay I made sure it's on TDC or 0 since the pointer is pointing at the bigger notch on my L16 pulley that I installed unto my L18, which should not make a difference. And like I said when I put a toilet paper inside the spark plug #1 and as I got closer to TDC (compression) the toilet paper pop out so I know for sure that it was TDC cuz one can set at the 0 mark but can be 180 degrees oposite, right? So now that I am at TDC, my spindle on distributor does not look like you picture it's a little off. So how should I make it look like 11.28 or 11.25 beacuse this is for sure. Now as if you are standing in front of the engine, the first cam lobe looks like 2 ocklock and the second one at 10 oclock but then again my slotted, where the distributor rest, looks different than your picture which you posted earlier. So when i take off the distributor cap and try to index it, it looks like the metal part of rotor will barely make contact with #1 of distributor. The rotor actually looks like it's between #1 and #3.

[banzai510(hainz)]

I look at the second lobe when look thru the oil cap hole.

when lobe nears 9 oclock I know the intake is closing on comp stroke.

then I dial it up to 0 on the crank. This is top dead center.

No toilet paper needed!!!!!!!

 

now ck the oil pump drive /dizzy spindal. it has to be in that photo exactly.

Look closeley if i had a long scew driver it would extend to the right of the top hole and left of the bottom. This is a timmed oil pump drive.

If not line up the dimple as per the vid. reinstall(with oil) till its correct as it slight will move or catch the worm gear wrong and can be off a tooth.

 

install dizz till it locks down and thats #1.

It should be very near a plug wire(1) and have enough adj with the timming plate to dial it in and start the vehicle.

 

If it pointing inbetween 1&3 then you have the wrong pedastal or oil pump is still wrong. if sure the oil pump is good and still points between 1&3 you have the wrong set up and only way to make the rotor point to #1 plug wire better is to drop the oil pump and move the spindal toward #1 plug wire.

[racerx]

hainz,

 

You the man...yeh that's why I was asking about the second lobe and the reason why I was using the toilet paper is cuz, I did not have any help. If I had help I can have someone stick like a wire or screw driver to number one spark plug and if piston comes up then I know that I am getting closer to TDC or compression.

 

I have a feeling it's the right pedastal, wait......would it make a difference if now I am installing into an L18? I am assuming it will be okay but now I have an L18 with an L16 dizzy?

 

Maybe this is the reason why the car would not fire up, it would crank but not start. oh well back to the drawing board.

[racerx]

Got it running thanks to all, specially to Heinz. Set my timing at 8 and sounds good. A little bit more power than my tired L16. I realized why the oil pump shaft has to be at 11.25 and once I got this to line up, evrything else went easy, timing, etc.