Davepar

Davepar

Well Known Member
The Van's instructions for installing the prop governor indicate the engine should have studs installed. My engine does not have studs pre-installed. I noticed on Walter's site that he used some SAE 5/16" x 1-1/4" grade 8 bolts.
(click to enlarge)


Is that still the preferred route? And where should I get those bolts? I assume not from Lowes. Or where can I find the studs if that's the way to go?

Thanks,
Dave
 
Doh! I just looked in the goody bag that came with the engine and found 4 studs that look like they'll work.
 
How far do the prop gov studs go in?

Hello,

I found the studs in the bag as well. I assume the harder to turn thread goes into the governor adapter and the nuts will go on the easier to turn threads. Using the double nut method, is there a correct depth to turn these in to, or are there stops? Also, do you use #8 nuts and lock washers to hold the governor and bracket on?

TIA
 
Yes, those are the Studs! The reason we don't install them is they are installed to different heights for different governors. The end that the nuts don't go onto easily, is the end that goes into the engine. Double nutting is the way to install them. Install them to a height that will yield one thread exposed out of the mounting nut with the gov mounted on the drive pad. They are universal and will work with various installed depths with any of the currently supplied prop govs. The studs work better the bolts but you could use high quality bolts as well. Many governor mounting flanges will not allow the use of bolts so studs are the only way you can go with those style prop govs.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at you own risk."
 
Thanks Mahlon, one more question

I have one in to the correct depth, but the other three seem to have bottomed out. (the nuts will turn before the stud will) I stopped for fear of causing damage. Is this a case where I just need to apply a bit more torque? The studs have all thread showing past the governor, but there is far more than 1-2 threads showing. Is there a trick to getting the nuts to lock better?

Appreciate your help,
 
If you have adequate thread engagement from the stud to the drive adapter then you don?t need to screw it in any further. Remove the stud in question and examine the depth of the hole you are installing into. You will be able to see if you are bottoming by making a depth measurement with an unfolded paper clip and comparing it to the stud. If you are bottoming you have more then enough thread engagement. If you aren't and you want to install it deeper, really tighten the double nuts against each other and proceed. If that won't get it done, you may have to use a stud driver tool to take the place of the double nuts. If you have more then one thread exposed past the mounting nut with the stud properly engaged in the drive pad, that is OK.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are
hopefully helpful to you. Please use the information provided
responsibly and at you own risk."
 
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Mahlon, following up on mounting prop governors, 1) should the nuts be safetywired? I've never seen them done that way other than the pic in this thread. Also, 2) should gasket sealer be used or not? My Jihostroj governor is seeping preservative oil just sitting there in spite of tightening them as tight as I dare.

Thanks!
 
Pete,
I use stars
Randy,
..unofficial torque on 5/16 course governor mounting nuts is tighten until the open end slips off and starts to round the nut off. Course threads don't apply a lot of squeezing power on the gasket, when torqued to standard recommended torques, like fine threads do. The gasket is also very firm, if you are using the one with the screen in it, and is sealing up to 300 psi on a gov when the engine is running. They can weep if attached with course threaded studs and the are torqued to standard torques. the gaskets will also weep oil on a fresh installation until it all weeps off the edges.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are
hopefully helpful to you. Please use the information provided
responsibly and at you own risk."
 
Just as a data point, I had more than a few threads exposed, especially on the top stud which didn't go in quite as far as the others. The studs are bottomed out or all the way through for the open holes. I have an MT prop governor on a TMX-360.

I used a nut, star washer, and regular washer, in that order. I see in my notes that I found a torque call out in the MT instructions of 140 in-lb for the nuts. Nothing is leaking so far, but I'm not even close to starting the engine yet.

Pictures:
http://www.dualrudder.com/rv7/2005/12/07/818

Dave
 
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mahlon_r said:
Course threads don't apply a lot of squeezing power on the gasket, when torqued to standard recommended torques, like fine threads do. The gasket is also very firm, if you are using the one with the screen in it, and is sealing up to 300 psi on a gov when the engine is running. They can weep if attached with course threaded studs and the are torqued to standard torques. the gaskets will also weep oil on a fresh installation until it all weeps off the edges.
Mahlon
Click to expand...
Thanks Mahlon. I'm running a WW 151 prop which requires higher pressure -- IIRC the governor has a max pressure of 425 psi versus around 325 for a normal Hartzell application. Higher pressure means more propensity to leakage. Would gasket seal help, or is there some reason not to use it?
 
I have a McCauley Governor on an 0-360 A1A and used the internal star washers that came with it. The way the flange is, you need to use studs and double nutting would be difficult. I actually had to make a special wrench just to tighten some of the nuts.

While we are on this subject, be aware of the plate that needs to be on the back of the adapter. It is a spacer plate that keeps the gears in the accessory case from being damaged by the prop gov and allows the gov to be bolted down all the way to prevent leakage. Sometimes this plate gets inadvertantly removed with a gasket and gets overlooked in installation of the gov. There is an SB on it from Lycoming. You can find it on their website.

Roberta
 
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