L18: Hard to Start and Does Not Want to Turn Off

[rude_day]

First off i drive a datsun 521 with a L18 & an A87 head if that matters?

 

Well today i want to adjust my carburetor because it annoyed that i have to pretty much "stall out" just to turn off my truck

 

so my question is what do i do?

i know how to adjust the timing, fuel mixture & idle

i adjusted all 3 but now my truck runs like crap & back fires threw the intake here & there.

 

& so your guys know my PCV hose is not connected & also does any know where to connect the wires on a carburetor?

[motavated]

made i mistake. I dont know....

[Zeusimo]

Running Too Rich

Also Called Deiseling

[datzenmike]

The above. You can't adjust the fuel mixture, that is set by the jets that are in it. You can adjust the idle mixture and speed though. Overheating, too hot a range of plugs or too high a compression can also cause dieseling.

 

Timing at 12 degrees before TDC

 

Valve lash set at 0.008" intake and 0.010" exhaust' when they are hot. A tight valve won't close properly and can allow the combustion to leak out into the intake and back fire.

 

Valves and timing must be set properly or there is no sense adjusting the carb

 

Idle mixture... turn mixture screw in and out looking for the fastest smooth spot. Turn idle speed down if it went up and repeat until you can't make it run any smoother . 

 

 

This assumes the carb is working properly and idling at 750-850.  Choke is not on and motor warmed up.

[uberkevin]

I had this problem once and I checked my points and the gap was... I think there wasn't a gap.

But it might be the other way around there could have been to big of a gap.

 

Maybe check the distributor..

 

Are you running a matchbox dizzy? My guess is no??

[rude_day]

The above. You can't adjust the fuel mixture, that is set by the jets that are in it. You can adjust the idle mixture and speed though. Overheating, too hot a range of plugs or too high a compression can also cause dieseling.

 

Timing at 12 degrees before TDC

 

Valve lash set at 0.008" intake and 0.010" exhaust' when they are hot. A tight valve won't close properly and can allow the combustion to leak out into the intake and back fire.

 

Valves and timing must be set properly or there is no sense adjusting the carb

 

Idle mixture... turn mixture screw in and out looking for the fastest smooth spot. Turn idle speed down if it went up and repeat until you can't make it run any smoother . 

 

 

This assumes the carb is working properly and idling at 750-850.  Choke is not on and motor warmed up.

 

thats what i ment the idle mixture screw

 

my valves are fine i recently put a new timing chain and adjusted all the valves before turning it over

also i cant really adjust my timing because it bounces back and fourth

[rude_day]

I had this problem once and I checked my points and the gap was... I think there wasn't a gap.

But it might be the other way around there could have been to big of a gap.

 

Maybe check the distributor..

 

Are you running a matchbox dizzy? My guess is no??

well i have a new point but i didn't properly gap it but i"ll do that tonight

 

no it is an L16 dizzy

[uberkevin]

Try to finnd a matchbox man

I'm pretty sure there is one for sale cheap right now

On The forsale thread.

 

My l16 dizzy was broken or something

And it would always lose its gap. Must have been to old.

Once it was off by a tiny bit and my truck wouldn't even start

[rude_day]

well i adjusted the point & it started from a cold start just fine

 

so now just have to tweak the timing

[uberkevin]

Couldnt find the matchbox I thought I seen.

But I have one, its missing the pedistal 'shipped to me that way'

If you want it pm me. Idk if you could find a pedistal seem it would be hard.

 

Do some research on electric dizzy on here. There's a few things

You can chose from to change from point.

[uberkevin]

How would she start before?

[rude_day]

Couldnt find the matchbox I thought I seen. But I have one, its missing the pedistal 'shipped to me that way' If you want it pm me. Idk if you could find a pedistal seem it would be hard. Do some research on electric dizzy on here. There's a few things You can chose from to change from point.

 

yea i want to switch to electronic soon but just not sure which one to go with

 

& the truck would just site there while i'am just cranking & cranking even gave it gas but it would still just crank

[uberkevin]

Yeah mine would do the same.

Did you drive around the block?

 

Glad it started good then sounds like good news.

 

 

[uberkevin]

I'm not finding a 521 thread nor project datto thread? What's up with that?

and oics of this beast!!

 

Must get some oics man.

[rude_day]

yea i drove it but i need to lower the idle

 

me either thats why i posted my motor problem 

 

do you know how to post pics without a photo bucket account etc. ?

[uberkevin]

I don't know if there is a way. And if your on a phone there isn't a way.

 

Photo bucket account is the easiest way to post a oic.

 

If on a computer there is a icon you push that is kinda above where

You type say ..................... up from the last dot Idk. But once you click on

It it should bring up a place where you enter the URL that you get from

PB after you upload it chose the middle of the three URLs to chose from.

 

At least that's how I do it on the computer

 

Good luck lol

[rude_day]

ok i'll try

 

 but i'll just go the the mechanic and i'll just pay attention to how he does it

[datzenmike]

 

also i cant really adjust my timing because it bounces back and fourth

 

This could be because the idle is too high. If so the vacuum advance will affect it. Just pull the hose off the dizzy and set timing. Put back on. You should be able to turn the mixture in till it stumbles then out until it stumbles and pick a spot half way between where it idles the smoothest/strongest. Turn idle down and repeat. Keep doing even if 5 times until you can't make any improvement.

[rude_day]

[rude_day]

This could be because the idle is too high. If so the vacuum advance will affect it. Just pull the hose off the dizzy and set timing. Put back on. You should be able to turn the mixture in till it stumbles then out until it stumbles and pick a spot half way between where it idles the smoothest/strongest. Turn idle down and repeat. Keep doing even if 5 times until you can't make any improvement.

oh ok i haven't tired that but i will tomorrow morning thanks

[uberkevin]

Sweet truck man!

 

How's the engine bay and insid cab?

[rude_day]

Sweet truck man! How's the engine bay and insid cab?

dont have pics of those but will soon

[racerx]

how does you spark plugs look and smell like?

[racerx]

what kind of carb?

[banzai510(hainz)]

also i cant really adjust my timing because it bounces back and fourth

 

WHAT??????????

pu tthe light on #1 plug wire and look at the crank it sahoul be steady

Now if its bouncing around this is a BIG clue.

You ck the wiggle of the dizzy shaft from sisde to side. maybe bushing or worn out.

 

I would do the idle around 10 and the spped set screw is on the back of carb. cycle the linkage and youll see a stop. a threaded screw the pushed the carb open or close.

 

 

this is a simple fix.

If you can do a timming chain you can do this.