L20b cured! (thanks guys!)

[banzai510(hainz)]

Well I always thought this truck was running since you been on here.

 

motor is at TDC on this vid 11.28 on the spindal

[herculesinwyoming]

i have had it running, just never have been able to get it to run well. always too rich and wouldn't idle down. yesterday when i adjusted the valves they were all tighter than my .006 feeler guage. Compression came up a good 30 pounds per cylinder after the valves adjusted. Always had to be at full advance on the distributor to get it to run.

this is the first time i really have gotten serious about finding the true issues.

I do Have Mr raiders truck and his engine runs perfect. I think its a good thing for me to figure out my engine so i can be a better datsun care taker.

[herculesinwyoming]

got this far, and then worked called, how much play is acceptable on the distributor shaft, mine moves just a little bit.

i will have more time tomorrow to spend on this.

[banzai510(hainz)]

the spindal is correct!!!!!!!!

Now loosen(just loosen) the timming plate on the dist side(under neath) the little 8mm bolt.

Then put the dizzy on till the rorotr locks down

hopefullits pointing close to the #1 plug wire.

then adjust the timming plate so the timming plate will be in the middle of its movment on the main hold down bolt(10mm). Once in center then you can lock the 8mm bolt. From there you should have enought adjustment to get to 10-15 deg with the light.

 

you coul take anothe rphoto with the rotor where it poits too and then with the cap on to see wherew the #1 plug wire is at. But I think you get the jest with the vid and should start up and run better.

 

Or you coul have done what Datsunaholic said just loose both locking bolts and just urn the dizzy till it ran better. The you could tell how far you were off.(kinda like Chevy dist) you and turn them all the way around

[herculesinwyoming]

i will do that when i get off work

[herculesinwyoming]

Ok today i put in brand new condensor, new points, waiting on a new cap and rotor, but the ones i have are pretty new.

heres how things look right now .

[herculesinwyoming]

now i have to find the darn lock down bolt for the distributor. I cant find it.

[banzai510(hainz)]

put C LAMP ON IT.

a oil pan bolt is the same.

 

dont you have a whole spare ruck to scam parts?

[Eagle_Adam]

dont you have a whole spare ruck to scam parts?

 

THIS

[herculesinwyoming]

i found it, it fell below the truck. Its darn cold out today so i am coming in often to warm up.

I have things about ready, fresh plugs are going in next and i think thats about it. Fuel is flowing well and the fuel filter looks darn clean.

about time to fire it up?

[Silvester]

Fire it up! Curious to see what you come up with. I will be tackling my ticking l20 this Sunday.

[banzai510(hainz)]

Dont you just hate this.

So close to finding out if this will run and then they dissapear.

 

totally this was about a 15 min job to figure out TDC and center the dizzy

 

IZ got to know if this RUNS!!!!!!!

[moparvwfreak]

dont feel bad, when i first got my first 73, it ran but crappy. i spent hours learning.when i threw my L20 in the beater, i had to use the video to figure a bunch out. now its 2nd nature. i am resealing another L20 with a new timing set. i hope i can fire it right off the bat.

[herculesinwyoming]

sorry, i work for the railroad, crazy hours,

She fired right up, and runs like crap, something is off in the carb, it is dummping fuel like crazy, i appreciate all the help. timing just needed minor adjustment to be correct.

the fuel is way above the mark on the sight glass now, float must have failed and sunk lol. i have a good carb on the raiders truck.

 

Mine has good compression but its burning oil. too

[banzai510(hainz)]

Damn! I though I had it.

Carb must have been bad already

[herculesinwyoming]

i rebuilt it a while back, but i guess something is wrong with it for sure.

being that the raiders truck was a reliable driver, i may just swap the engines and rebuild and save my old l20 as a spare. I will have to get his truck stripped down and sent to scrap before long. city doesnt like wrecks sitting in driveways. His old 78 runs perfect.

[banzai510(hainz)]

i THINK IT WOULD BE EZER TO SWAP A CARB.

I know they harder to swap on a emission filled L motor but still ezer than swpping out a motor.

 

be nice to know you rebuild it. Most people dont rebuild them right. I gave up doing stock carbs. I just swap a stack of webers I have just for trouble shooting.

[herculesinwyoming]

Good point, maybe i will just try the other carb. if that fixes it maybe i should swap in the distributor from the 78.

[herculesinwyoming]

I will follow Hainz advice, and swap carbs when i get home from my railroad trip.

I am starting to dislike the hitachi carb.

if the carb swap works, i will post video results.

[herculesinwyoming]

have some time to work on the truck today, pulled a fuel line getting ready to swap carbs, decided to crank it over real quick to check fuel flow. Pump Put out nothning. I double checked by putting some air to the fuel lines and they are all clear. Pulled the pump and it was leaking gas where the cam arm is.

Im going to swap in a new pump before i go pulling carbs.

[izzo]

Check your oil, too.... gas in there isn't good

[herculesinwyoming]

Will do! Also there isnt any issue on running the bigger 1978 fuel pump on my 76 is there?

Now that i have decent pressure my carb is leaking from every gasket.

[izzo]

theres two styles. the brass smaller one and the larger one. they both pump the same IIRC, about 3lbs. The larger one is superior and usually lasts longer, and i hear rebuild kits pop up for them sometimes.

[herculesinwyoming]

i have mr raiders crashed truck for parts , i put that pump on mine, just didnt know if they flowed more, my old one is oem style too.

i checked fuel lines and return lines, everything has been gone over, just the carb left, heading out to pull it now.

[datsunaholic]

'78 fuel pump is the same as the '76 fuel pump. There were only really 3 types of factory 620 pumps: '72-74, which was small and designed for no return line (lower lock pressure and lower volume) and the '75-79 version which was larger and usually requires a return line as it can force the float valve open on both Hitachis and (almost always) on Webers. These are diaphragm pumps with cast aluminum housings and are the preferred version.

 

Any difference within those ranges was simply a difference in how the outlets pointed or had shrouds on them. Inconsequential to operation.

 

Aftermarket pumps generally are all the same- stamped steel housing (that looks brasslike, but it's not) plunger pumps. Some early-type replacements have one plunger, late have 2.