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Prop Governor

T

T.O.Craig

Well Known Member
Howdy to all...
I have been following the MT governor problem over the last week and I am not sure where to start or what to do. I have a P-860-3 #13G00_ . The last s/n number I can't read. I also have a Lycoming YIO-540-D4A5 engine number EL-35740-48E that was shipped from Vans 9/2013
There is talk about ratios that drive the pump, narrow and wide deck motors ect.
Should I just contact MT? Just not sure where to start? I am getting close to a start, and certainly don't want an overspeed problem like one gentleman had on his first flight..

As always thanks in advance for the help!!
 
This is what I would do if in your shoes.

1. I would see if Van's will take your unused MT governor back in exchange for the wide deck Hartzell governor. This will cost you the price difference obviously. Hartzell really stresses different govs for different ratios. MT doesn't. Be extra vigilant as Van's has mislabeled and mishipped the Hartzell govs in the past.

2. If the above doesn't work, I would send your PG to MT for the update before flying.

3. If you want to fly quickly, and peace of mind means more than $1600 ish, I would just buy a Hartzell and then sell your updated MT on the open market when the dust settles.

Actually, I actually am in your shoes in a way when I get my engine and prop back, the only difference is that my MT is non returnable, and non-updatable.
 
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woxofswa said:
This is what I would do if in your shoes.


3. If you want to fly quickly, and peace of mind means more than $1600 ish, I would just buy a Hartzell and then sell your updated MT on the open market when the dust settles.
Click to expand...

Or buy a PCU-5000X. I have installed this governor on an RV-8 and and RV-10. Both installs have been trouble free.

Carl
 
Carl Froehlich said:
Or buy a PCU-5000X. I have installed this governor on an RV-8 and and RV-10. Both installs have been trouble free.

Carl
Click to expand...

That could be an excellent option, just not primary for me. My experience with that factory in the Czech Republic hasn't been so pleasant. I question materials more than engineering, but I'm no expert.

With Hartzell I like that you can call right to the source during normal business hours and someone extremely knowledgable who speaks your language will go out of their way to answer your questions and explain things on a very deep level. I've held the US and Czech govs in each hand simultaneously. Yes I readily admit that I am a bit jaded at the moment.
 
It appears (someone correct me if I am wrong) that the PCU-5000 is very similar to the MT 860 in external dimensions, whereas the Hartzell is larger, and may require some reworking of the cowling and baffling.
 
aturner said:
It appears (someone correct me if I am wrong) that the PCU-5000 is very similar to the MT 860 in external dimensions, whereas the Hartzell is larger, and may require some reworking of the cowling and baffling.
Click to expand...

That's true but very minor. Basically it's the opening in the Captains side front eyebrow cavity on the bottom side of the top cowl. We did the rough modifications in the field in about 3 mins with a Leatherman tool, which will be easy to final finish when the time comes.
 
woxofswa said:
That's true but very minor. Basically it's the opening in the Captains side front eyebrow cavity on the bottom side of the top cowl. We did the rough modifications in the field in about 3 mins with a Leatherman tool, which will be easy to final finish when the time comes.
Click to expand...

Myron, which model did you get -- S-1-26?
 
I don't have one yet. I just used a donor to get home.

I will say however that the MT always chased rpm +/- 10 or 15, especially the first part of a flight and I just wrote it off as indication artifact error. The donor Hartzell stayed glued to wherever you set it and never required any adjustment.
 
woxofswa said:
I don't have one yet. I just used a donor to get home.

I will say however that the MT always chased rpm +/- 10 or 15, especially the first part of a flight and I just wrote it off as indication artifact error. The donor Hartzell stayed glued to wherever you set it and never required any adjustment.
Click to expand...

I asked because I've been trying to decrypt the Hartzell application guide to figure out the exact model for a narrow deck 540. Right now I think it's S-1-26 for the narrow deck and S-1-32 for the wide deck.

I guess I'll shoot off an e-mail to Hartzell and see if they can confirm.
 
rleffler said:
I got a S-1-32 in my FWF kit
Click to expand...

That's why I'm trying to nail this down. What we've all learned from the prop gov mess is the narrow deck prop gov drive assembly turns at a different ratio of the wide decks (which is what Van's sells) which is why I want to be sure I get the right prop gov for my narrow deck.
 
I spoke with Hartzell yesterday, for my narrow deck IO540 they said the correct model was S-1-26.

Not sure if it matters but I did tell them I'm running a 3 blade MTV-12B prop.

Gary
 
GaryK said:
I spoke with Hartzell yesterday, for my narrow deck IO540 they said the correct model was S-1-26.

Not sure if it matters but I did tell them I'm running a 3 blade MTV-12B prop.

Gary
Click to expand...

Timing is everything! :p:D I shot off a note to Hartzell just a few minutes ago asking the same thing.
 
Hartzell Models Confirmed

I just got an e-mail back from Alex Krauskopf, tech rep at Hartzell and he confirmed what they told Gary:

Narrow deck model is S-1-26

Wide deck model is S-1-32

Also if you are using the throttle quadrant, the necessary extension part number is 103568 governor arm extension.
 
WIDE VERSES NARROW

With all this info exchange, I will be making a call to MT and be sending the PG back for service.
Can anyone explain the difference between narrow and wide deck engines? Is it a physical size? Seems like internal ratios might be different.
Thanks
 
PCU 5000X install

I thought I would post a couple of pictures of the PCU5000X installation, replacing the MT P-860-3 on my WD Lycoming.

It is truly plug and play, only having to adjust the clocking, which is a matter of cutting the safety wire on the 6 screws, adjusting it where you want it, then re-tightening the screws and adding safety wire. No baffling modifications.

Here is the correct part number (I'm posting it here because I initially received the wrong Hartzell and PCU5000X).


Here they are side-by-side, MT on the right:



Here it is mounted:



I ordered the PCU5000X before I found out my MT is not affected. Mine was built in 2008 and was overhauled 100 hours ago, so if someone wants it let me know. I will let it go for $600 plus shipping CONUS.

Vic
 
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Vic.

Need one while mine goes in for service. I'll take if available. My ph number is 5097278850....been looking for a excuse to talk to the legend so here it is:)
 
Great info-couple of questions

Vic, thank you so much for posting the pictures of the PCU and giving the part number, I have been getting the go around tracking that down from direct communication with PCU. I did want to confirm you have the IO-540 D4A5 in your latest 10?
Also, did you note/order a lever offset (in degrees) or did you just do that at install, I know for my 7 I had to move it a bit from how it arrived from the factory, so really not an issue.
Cheers & thanks again for the info. Mike :)
 
WrightsRV7 said:
Vic, thank you so much for posting the pictures of the PCU and giving the part number, I have been getting the go around tracking that down from direct communication with PCU. I did want to confirm you have the IO-540 D4A5 in your latest 10?
Also, did you note/order a lever offset (in degrees) or did you just do that at install, I know for my 7 I had to move it a bit from how it arrived from the factory, so really not an issue.
Cheers & thanks again for the info. Mike :)
Click to expand...


Yes, I have a D4A5. And it was not clocked properly, but I think it might have been because they rushed it out the door after they initially shipped the wrong one. It is easy to clock---just take off the safety wire, loosen the 6 screws and rotate it to the position you want, retighten and safety wire.

Vic
 
Loaner

I installed Vic's and am back flying. My plan is to reinstall ours after the sb is done. Therefore, if anyone would like to loan Vic's, we would be happy to send to you. Mt is stating two week turn time at this point in their schedule
 
Has anyone verified if the flyweight design in the PCU5000X is the same as the Hartzell or the MT? From what I've heard elsewhere, the Hartzell uses a one-piece machined part, but MT used a 2 weld system on the ones that are bad, and a single weld (I hope I'm getting this right) weld on the new ones they are putting in. The question is, what does PCU5000X use? If it's a single machined part like Hartzell I'd be optimistic about either of those 2 options. I also am curious as to what my pre-2008 (mine is probably 2004-2005) P-860-3 has for a design. It sounds like they must have went to the weaker weld system somewhere around that 2010 mark. Not sure why they would have done that. But I'd be interested from a design perspective how my old one compares to the Hartzell and how the PCU5000x compares also. Right now I'm not too worried about my old P-860-3, but considering I have over 1200 hours on it, maybe I'd be interested in buying a new one and having this one overhauled. It all depends on the designs involved.
 
When I spoke at length to Sean regarding the PCU-5000X he assured me that the desings were completely different. We didn't know it was a weld issue at the time, so perhaps Sean will chime in here.

Vic
 
I just replaced the MT P860-4 with a PCU5000X (RV-8 equipped with an IO-360). The MT PG was due to go back for the 72 month rebuild.

I spoke to Sean (APS) at length about the PCU vs MT design. He answered all my questions and provided a lot more info I didn't know.

Sean indicated they are considering a change to the PCU5000X. I believe he said they are looking at putting lighter weight flyweight assemblies in them.

The PCU5000X I received need to be re-clocked, after that it bolted right on. The RPM was set correctly and required no additional adjustments.

To me the response of the PCU seems more linear and slightly less abrupt then the MT.

Not RV-10 related. Sorry for the thread drift.
 
Supplier of Hartzell S-1-26

Auburntsts said:
I just got an e-mail back from Alex Krauskopf, tech rep at Hartzell and he confirmed what they told Gary:

Narrow deck model is S-1-26

Wide deck model is S-1-32
Click to expand...

Have you found an reasonable priced supplier of the S-1-26?
 
Hartzell governor.

The pictures poste by Vic shows that the MT and PCU-5000X governors are similar in shape and size, easily interchanged without need to change the control cable mount.
Is this also true for the Hartzell S-1-26 governor?
Does "clocking" refer to the positioning of the control arm of the governor? Meaning removing the 6 screws and turn the orientation of the control arm to fit your installation.
Thanks.
Johan
 
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