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Engine shake at shut off


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#1 620owner

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Posted 12 June 2018 - 04:22 AM

I'm getting a slight engine shake at shut off. Just swapped the tranny, wondering if I weakened a motor mount ?

I don't think I have a broken motor mount, drives great but it just started this after the swap.

Could it be something else ?

 

 



#2 nl320what

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Posted 12 June 2018 - 07:21 AM

Usually my 620s would wobble when shut off cause of dieseling alittle after swapping in a Weber without the fuel cutoff solenoid anymore.


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#3 racerx

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Posted 12 June 2018 - 07:42 AM

Try put it in gear before shut off see what happens.

#4 Charlie69

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Posted 12 June 2018 - 08:10 AM

Ad the fuel cut solenoid.

 

https://www.piercema...928.060&Submit=

 

This is fom Pierce Manifolds.



#5 620owner

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Posted 12 June 2018 - 08:36 AM

Running original, Hitachi Carb. 

Not acting like dieseling, just a little stumble/rock when killing the engine.



#6 nl320what

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Posted 12 June 2018 - 09:30 AM

Not completely a diesel run-on, I know that shut-off shake/rattle/wobble all too well for that half second.

 

Bad gas, vac leak, gunk in shut off solenoid maybe ?


63 NL320 4x4= 5SPD,PDB,PTS,C3H8 Powered... is 88% Completed as of 6/4/2018.

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I need NL320 Doors or complete L320 Doors to use, will barter:

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#7 paradime

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Posted 12 June 2018 - 09:40 AM

So this is something it had not done before? It's definitely not the mounts though. They're designed to let engine wobble. Did you change the timing by any chance? beyond that, I'm with nl320what. 


36028318531_e4983e3724_m.jpg


The blocked list is getting bigger-but you were the first.

 

 

 

http://the510realm.c...php?f=3&t=15379

 

http://youtu.be/H4rYbyudrhA?t=55s  https://youtu.be/GZtp6PiFlTI?t=2s https://youtu.be/G4RjPtffZHI?t=2s

 

 

 

 

 

 

 

 

 


#8 datzenmike

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Posted 12 June 2018 - 10:54 AM

Did you remove the engine when doing the trans? May have upset something.

 

 

Check the idle cut is connected. It should make a clicking sound when the ignition is turned on/off/on/off.

Did you change spark plugs?

Did you replace thermostat?

Are you using a different gas than normal?


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#9 620owner

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Posted 12 June 2018 - 11:16 AM

No didn't remove engine. I'll check the idle cut.

nl320what said bad gas.... come to think i'm running out a tank from last fall and it's down under 1/4 now.

Didn't give that a thought. The truck sat over the winter with a full tank in the garage.

I just swapped the tranny and  started driving it again. I'll top it off with premium and see if that makes a difference.



#10 datzenmike

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Posted 12 June 2018 - 11:19 AM

I'm getting a slight engine shake at shut off. Just swapped the tranny, wondering if I weakened a motor mount ?

I don't think I have a broken motor mount, drives great but it just started this after the swap.

Could it be something else ?

 

I'll take that as not removing engine.

 

Try the gas, you have to fill it up anyway.


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#11 Doctor510

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Posted 12 June 2018 - 02:01 PM

Try put it in gear before shut off see what happens.

AKA Clutch Kill



#12 flatcat19

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Posted 12 June 2018 - 02:56 PM

Just be in the habit of using the clutch to kill the car.

You can't hang if your nuts haven't dropped...it's physics


#13 datzenmike

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Posted 13 June 2018 - 09:23 AM

Causes of engine 'run on' or 'dieseling'

 

 

Idle too high for idle cut to have any effect.

BCDD set incorrectly causing a fast idle.

Idle cut stuck open, or insides removed or carb replaced with one that doesn't have one.

Carb flooding, making the idle cut useless.

 

If the idle is correct, carb not flooding and idle cut working there shouldn't be a problem. If you have an old carb without an idle cut, the following may cause run on...

 

Engine running too hot.

Spark plug range too hot

Excessive carbon build up

Compression too high / Too low an octane gas


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