Author Topic: Choke  (Read 6337 times)

Offline Smitty31

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Re: Choke
« Reply #15 on: October 19, 2017, 05:01:35 PM »
i did excatly that it was 14.3 volts
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Online bd

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Re: Choke
« Reply #16 on: October 19, 2017, 05:41:32 PM »
Connect a DC voltmeter between the battery negative post and the choke t-stat housing then start the engine and measure the voltage.  What is it?

^^^^  Read this again.  The measurement validates the ground path, before proceeding to the next step.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Smitty31

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Re: Choke
« Reply #17 on: October 20, 2017, 06:54:31 AM »
Ok let me start by saying I know very little about these meters. So I'm including a pic showing how mine is set up and it was this way when I took the readings. Black lead on negative post of battery and red lead on metal t housing on carb. 0.00 or on the metal spade 0.00 with engine off. Reading with engine on black to ground and red to elec. spade on t housing 14.49
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Online bd

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Re: Choke
« Reply #18 on: October 20, 2017, 08:09:07 AM »
Good!  Now, repeat with...

...Black lead on negative post of battery and red lead on metal t housing on carb ... with engine RUNNING....
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Smitty31

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Re: Choke
« Reply #19 on: October 20, 2017, 10:09:40 AM »
Ok it is 0.04 black lead on negative post and red lead on t housing.
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Online bd

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Re: Choke
« Reply #20 on: October 20, 2017, 10:52:33 AM »
Good.  Now, mark the choke t-stat adjustment with a pencil line across the edge of the t-stat and housing where they meet, then slowly remove the t-stat paying close attention to whether the link inside the housing is caged within the socket at the end of the bimetal spring (imaged earlier).  Make sure there is NO GASKET between the t-stat and the housing, then reinstall the t-stat so the link is caged by the bimetal socket and the tang on the housing engages the notch at the edge of the t-stat (imaged earlier). 

Was the link caged by the bimetal socket when you removed the t-stat and does the line you drew across the edge of the t-stat still line up?
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Smitty31

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Re: Choke
« Reply #21 on: October 20, 2017, 12:36:36 PM »
I will do it a little later and let you know.
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Offline Smitty31

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Re: Choke
« Reply #22 on: October 20, 2017, 01:46:18 PM »
Ok did it everything aligned back up.
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Online bd

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Re: Choke
« Reply #23 on: October 20, 2017, 02:16:55 PM »
1)  Was the choke link caged by the bimetal socket when you removed the t-stat?

2)  With the choke t-stat indexed to the tab and notch, the penciled mark lines up?

3)  Did the choke plate opening change any?
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Smitty31

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Re: Choke
« Reply #24 on: October 20, 2017, 06:42:11 PM »
The socket and tab was aligned the pencil did match the tab on the housing and no it did not help.
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Online bd

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Re: Choke
« Reply #25 on: October 20, 2017, 07:34:18 PM »
Take it back to the tech who overhauled and adjusted it to have him/her recheck the choke linkage adjustments (see the carburetor choke section of the 1986 Service Manual, beginning on page 6C1-34).  The problem with simply adjusting the choke t-stat is that the tab & notch won't align and the tab will prevent the stat from seating, possibly cracking the plastic cover when the screws are tightened.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Smitty31

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Re: Choke
« Reply #26 on: October 21, 2017, 05:46:54 AM »
When he drilled the pop rivets out and put screws in he removed the tab on the choke thermostat so it could be adjusted manually. Thanks for all the info I'll have him take another look
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Offline Smitty31

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Re: Choke
« Reply #27 on: October 21, 2017, 06:06:51 AM »
I downloaded manual in chapter 6 is about the choke. It said if the choke thermostat was receiving 12-15 volts replace the choke thermostat. I wonder why that is I thought 14 was good enough.
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.

Offline Smitty31

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Re: Choke
« Reply #28 on: October 21, 2017, 08:39:05 AM »
Never mind I understand now.
IF ITS WORTH DOING. THEN ITS WORTH DOING RIGHT.