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2017 Throttle/Governor Springs?

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nate0520 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nate0520 Quote  Post ReplyReply Direct Link To This Post Topic: 2017 Throttle/Governor Springs?
    Posted: Mar/04/2017 at 5:43pm
We can't seem to figure out how to set up our throttle return and governor springs... We added the spring indicated by the arrow (it came in the kit with the roll-over cap), and moved the governor spring to hole 5. The spring with the question mark was on there when the engine arrived; it seems to hold the throttle wide open... we can't find anywhere else that looks like that spring should go. 

Edit: Can't get the picture to work, here's a link  http://imgur.com/a/zM3Zp

I have a feeling we're missing something completely silly, but last year we bought the engine through home depot and didn't find out anything was wrong till we went through tech inspection. I'd rather ask someone than stet this up and do all our testing incorrectly!


Edited by nate0520 - Mar/04/2017 at 5:47pm
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Nate View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nate Quote  Post ReplyReply Direct Link To This Post Posted: Mar/05/2017 at 11:35am
I haven't personally seen the engines yet, but everything in your setup looks correct based on my experience with past years' engines. 

The question mark spring - That's your idle speed spring, and it's probably why your engine is idling too high - wide open as you say. Bend the tab to adjust its tension, but first loosen the screw near the carbeurator (otherwise your adjustment may do nothing). The screw I'm talking about prevents the butterfly valve (air inlet valve I think?) from closing too far and choking your engine to death during a return to idle. Once you have the spring set right and your engine is idling at the proper speed,  retighten that carb screw to prevent the valve from closing too far. I'm almost positive you will need to lessen the tension in that spring to lower your idle speed.

The throttle in your picture IS in the idle position, so that's right. You're allowed to change how tight the throttle nut is so your throttle doesn't creep when you're bench testing. Then loosen it up so that the spring you're point at will return the throttle to idle. 

Really to increase the throttle, the spring in hole 5 needs tension to assist your idle speed spring. The big throttle attachment lever with the heavier spring (spring you pointed at) is just a mechanism to make that happen. Depending on the amount of tension in the lighter spring in hole 5, that will make your governor speed increase or decrease. You can bend the spring attachment tab to change that tension.

I hope this doesn't confuse you more. Everyone else, please correct me if I'm wrong.
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nate0520 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nate0520 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/05/2017 at 5:11pm
Thanks for your reply. We haven't fired this one up yet but we will probably do so and just tinker with it. Some of the things you said seem contradict what we're seeing though (see new picture for additional reference: http://imgur.com/a/RAMbp). 


The carb adjustment screw is the little screw with a pre-load spring on it, in the area circled in red. Currently, the "air inlet valve arm" (not sure of its actual name; it's also in the area circled in red and pivots about the red dot) does not even touch the idle-adjust-screw when the engine is just sitting, as-pictured. The idle-adjust-screw is backed most of the way out, to a reasonable looking position. The red arrow next to the long thin rod/long thin spring indicates the direction of tension needed on the "air inlet valve arm" in order to return it to what we're pretty sure is idle, so the question-mark-spring seems like it needs to be puling the "governor arm" other way (the red dot next to the question-mark-spring indicates where the "governor arm" pivots). Manually applying pressure with your finger in that direction provides a reasonable amount of tension for the governor spring, and also returns the "air inlet valve arm" to idle (i.e. touching the idle-adjust-screw). I see how bending the tab at the question-mark-spring would change its tension, but it seems like that spring is just pulling in the wrong direction all together... I'll talk to the guys about firing it up monday or tuesday and we'll start tinkering, but it just seems like we're missing a place to the right of the "governor arm" to mount Mr. Question-Mark-Spring. 


tl;dr: we're pretty sure the question mark spring is pulling the wrong direction, but don't have a spot to mount it to have it pull the other direction. 
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adrive7 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote adrive7 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/06/2017 at 11:30pm
Your engine appears to be setup correctly. See instructions here

Start up the engine and play with it as it's running, it will make more sense.
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nate0520 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nate0520 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/11/2017 at 5:01am
Problem resolved, it was indeed set up correctly and it runs (and idles) just fine. It seems the airflow sucks the throttle body to the correct position for idle when the engine is running. I would never have guessed that! Thanks for the replies. 
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