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Truck not getting spark after head job/bottom end job


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So I Have everything in order when I try to crank the engine it chokes/wont crank proper ( crank stop crank stop )


But if switched # 1 and 3 it would crank fine.


anyone have any idea's ?

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Guest DatsuNoob
So I Have everything in order when I try to crank the engine it chokes/wont crank proper ( crank stop crank stop )


But if switched # 1 and 3 it would crank fine.


anyone have any idea's ?


Could be that the 1 wire isn't on the metal contact part of the rotor. put the 1 wire on the correct end of the rotor and place the rest of them as you would in the 1-3-4-2 counter clockwise.

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We dont have pics of the wires all the way to the spark plugs, but it kinda looks like the firing order is going in the 1342 pattern ,but its clockwise. And i agree with Datzenmike that you need to turn the dizzy a little more to make it line up with the number one plug wire.

The pics look like wires 1 and 3 go to the front of the motor, 2 and 4 appear to go towards the rear of the motor. I could be worng as the pics dont show all of it.

The firing order is Counter-clockwise.



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I had thought that aswell so i got a screw driver and expanded all the metal so it would have propper connection still same thing -_- . I feel like a retard for being able to work on a rotary and yet not the simple l18's

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going by the 2 distributor photos ABOVE looks like the dizzy could be turned more Counter clockwise.(i would hope that #1plug wire to the left of the cap locating clip!!!!!!!!!!!!!!!!!!!


looks like its kinda in btween the 2 plug wires more rotor points more to the left SO I ASSUME that #1 plug wire.


and when Points are open thats when the coil will fire


everything is on here



to me that vaccum adv seems like its in the wrong spot. Im not positive but mine is elsewhere.Esp a point dizzy?


just make sure the rotor is on a plug wire. You will assign this #1 and go 1 3 4 2 CCW fire order.


everything is in the above link.

if gas squirts in the carb

valves close good(valve lash)

and you have correct timming spark

its going to fire!!!!!!!!!!


to answer your PM


Did you watch my video?? or read the620.com tech section

Now get everything back to TDC.

You can leave the Valve cover on. just look thru the oil cap hole and when the lobe nears 9.30 position then look at the crank and dial it up to Zero.Lobe should now be close to 10oclock(intake)

now the oil spindal should be in the 11.28 position like you pitured


now put the dizzy back IN.

Now where it locks down that will be 1 plug wire.


Now adjust the dizzy so the rotor is RIGHT on a plug wire. Not in between. Thats #1 now go 1 3 4 2 Counter clock wise fire order.


Now if it doesnt go any father cause if the timming plate take the 10mm bolt out of the timming plate and adjust dizzy so #1 plug wire till its right on. Have some body start the car and it should start up.

This means somebody has a wrong timming plate/ dizzy mount mismatched where you could not zero up to #1 . Or orginally they moved the oil/dizzy spindal to dial up to #1.(points will be open)



also on back side of the dizzy is a 8mm bolt that holds the timming plat to the dizzy this can be loosen also to make the timming plate move more adv/retard also.

here is a photo of mine. notice where the vacuum adv is.


Can somebody confirm if they have a vacuum adv in that location towards the front like that.

here is a photo of mine. notice where the vacuum adv is. just ck yours they might be slight variations

L20 dist with vacuum  adv down TDC_thumb.jpg

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We've watched the video prolly twice and read the tech section on the620.com a few times aswell everything is checking out...


So tonight if I have time I will adjust the distributor counter clock wise to the max and try from there after that I will check in back of the distributor...


I apreciate all the replies...

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So I Have everything in order when I try to crank the engine it chokes/wont crank proper ( crank stop crank stop )


But if switched # 1 and 3 it would crank fine.


anyone have any idea's ?


Crank stop, crank stop.... is a sign of too advanced ignition. The cylinder is firing too early against the starter and stalling it. Perhaps the distributor needs to be turned clockwise to retard it some. I assumed the wire in the 5 o'clock location was #1, perhaps it's the 7 o'clock wire instead, in which case it's too advanced. If so, the distributor should be turned counter clockwise to bring it just over the rotor. This would agree with hainz's picture more. Hainz?

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OMFG It's alive , the whole time it was somethign that was so simple we over looked it.


I just now have to research on how to ajust the idle on the carb and figure out how to make the flaps close all the way. the previous owner's son had played with the truck and screwed the shit out of it . so now my engine uns just reving the crap out of itself... freakin weber 32/36


when I bought the truck the carb flaps seems to bee open all the time. not sure if it suppose to be... but yea thanks much for all the help...


the issue was the distributor being slightly off from #1

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Guest DatsuNoob

Glad to hear you got it going. "IT'S ALIVE! IT'S ALIIIIVE!!!!!" :lol: ...sorry, couldn't resist. So, is your mixture not right, choke adjustment? If it's a mixture issue, I would turn the screw in until it runs like shit, then back it out until it runs like shit, eyeball the threads and pick the middle. Always better to run a little too rich than a little too lean so things dont get too hot. I'm pretty sure only the primary stays open all the time, then after the choke heats up the secondary slowly opens up then they both stay open. I haven't had to screw with mine since I installed it, so my memory is a little hazy. There are a few carb related threads on here and I'm sure you'll figure it out. Well done :)


P.s. I'm sure a few of us are wondering what was the thing that was overlooked, what was it?

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lol FUK! lost a bolt for the water pump so now its leaking!... I'm fresh to carb systems so I'm looking through manuals for now .. going to home depo to see if i can find sa bolt that fits there. .. gots to tear the fan apart again tomorrow... but man i sounds like a v8 for the few seconds i had it on..


sorry to answer your question the thing that was over looked was the itmming part on the distributor. from what you guys had said above...


Again really apreciate all the help you guys have givin me.

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Its hard being a PIMP!!!!!!!!!


its a metric water pump bolt.


go to the junk yard and scam extra bolts.


be honest lossing one bolt should not make the water pump area leak.


use a good gasket and antiseaze the bolt to keep it from rusting also.

remeber not to tite on these it doesnt take much on Jap motors. read the book and see how little torq is needed.


time motor using a light.


the choke fLAP ON MANUAL WEBER DGVS. will be open untill you pull the choke wire. If its a eleltric and its wire is not hooked up it will start up cold fine but have proplems when warmed up.

Take photos.

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Hey guys sorry for delay been busy with work and my rx7 and side job.

Got the truck running im just no good at tunning the carburated engines so I dont want to screw anything up


Well I'm putting the truck up forsell. I find im no good at carburated engines.

truck has 4 new pistons reading 180 170 170 170 valve lash needs to be redone again to get 180 all around, we did a quick job to get the engine running


head has been hot tanked and machined

Block has been honed.


has all new gaskets timing chain cover, oil pan, valve cover, and head gasket

Comes with extra gaskets and stock carb

New alternator

all new fuse's

new ignition switch

Truck currently has a 32/36 webber on it

seat has big tear on stock bench


all in all body is clean. bought it off original owner looking for a way out of smog ( 74 is smog exempt )


asking 1500$

Locals only please

locasted in Nortern California , San jose


pictures will be posted tomorrow

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Yes after all that work, I'm going to have to stick with Fuel Inject engines.. I love the Truck tho really would like to keep it but i have to many vehices,


2007 r6

1993 rx7

1996 civic

and the

1974 620


My yard and garage is field with car bumpers engines , and misc engine parts from customers and myself...the trucks been in the garage for a while now and well it's done and I really dont want to deal with it any more after the broken bolts the pain of getting the timing chain cover on and all the other bs...


1500 obo , really im just looking for 1100 ( pay for what i paid for the truck and parts... just posted high cus i know people will low ball


408 833 0637

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