 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
richard.goode(at)russiana
Guest
|
 Posted: Thu Mar 14, 2013 11:24 am Post subject: hydraulic lock |
 |
|
A number of people have asked for the photos I wrote about, and they will be sent out tomorrow. The reason for not posting them directly was that I was under the impression that posting photos wasn't permitted on the Yak – list!
Anyway it is quite spectacular – the connecting rod failed, but the engine went on running for another 20 minutes until landing. The forces were so great that even the master rod was bent, which I have never seen before.
I would say that you cannot underestimate the risk of a hydraulic lock, particularly with an old engine and an oil pump check – valve that is worn/sticking and allowing oil through the oil pump into the engine.
It is also worth saying that we have recently received an engine that was hydraulic locked with fuel, in this case just a bent rod but clearly serious over – priming!
Richard Goode Aerobatics
Rhodds Farm
Lyonshall
Hereford
HR5 3LW
Tel: +44 (0) 1544 340120
Fax: +44 (0) 1544 340129
www.russianaeros.com
[quote][b]
| | - The Matronics Yak-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Yak-List |
|
|
|
| Back to top |
|
 |
pjsales(at)me.com
Guest
|
| Posted: Thu Mar 14, 2013 12:34 pm Post subject: hydraulic lock |
|
|
Richard-would you send photos to me?
PJ Ashura
pjsales(at)me.com (pjsales(at)me.com)
Sent from my iPhone
On Mar 14, 2013, at 12:21, Richard Goode <richard.goode(at)russianaeros.com (richard.goode(at)russianaeros.com)> wrote:
[quote] <![endif]--> <![endif]-->
A number of people have asked for the photos I wrote about, and they will be sent out tomorrow. The reason for not posting them directly was that I was under the impression that posting photos wasn't permitted on the Yak – list!
Anyway it is quite spectacular – the connecting rod failed, but the engine went on running for another 20 minutes until landing. The forces were so great that even the master rod was bent, which I have never seen before.
I would say that you cannot underestimate the risk of a hydraulic lock, particularly with an old engine and an oil pump check – valve that is worn/sticking and allowing oil through the oil pump into the engine.
It is also worth saying that we have recently received an engine that was hydraulic locked with fuel, in this case just a bent rod but clearly serious over – priming!
Richard Goode Aerobatics
Rhodds Farm
Lyonshall
Hereford
HR5 3LW
Tel: +44 (0) 1544 340120
Fax: +44 (0) 1544 340129
www.russianaeros.com
| Quote: |
===================================
//www.matronics.com/Navigator?Yak-List
===================================
cs.com
===================================
matronics.com/contribution
===================================
|
[b]
| | - The Matronics Yak-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Yak-List |
|
|
|
| Back to top |
|
|
tmckeon79(at)hotmail.com
Guest
|
| Posted: Thu Mar 14, 2013 2:39 pm Post subject: hydraulic lock |
|
|
Please send me the photo's of the hydraulic lock. Not too long ago I hydraulic locked my engine. I pulled the prop through multiple times after over a month of not flying. It still locked up. I do not have an oil drain kit, and I'm told oil from the intake valves caused it.
Tmckeon79(at)hotmail.com
From: richard.goode(at)russianaeros.com
To: yak-list(at)matronics.com
Subject: hydraulic lock
Date: Thu, 14 Mar 2013 19:21:01 +0000
A number of people have asked for the photos I wrote about, and they will be sent out tomorrow. The reason for not posting them directly was that I was under the impression that posting photos wasn't permitted on the Yak – list!
Anyway it is quite spectacular – the connecting rod failed, but the engine went on running for another 20 minutes until landing. The forces were so great that even the master rod was bent, which I have never seen before
| | - The Matronics Yak-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Yak-List |
|
|
|
| Back to top |
|
|
mark.bitterlich(at)navy.m
Guest
|
| Posted: Thu Mar 14, 2013 3:35 pm Post subject: hydraulic lock |
|
|
Thomas, I have intentionally stayed out of this discussion as there are many more expert than myself. But this needs to be said, especially with Richards comments about fuel hydraulic locks.
It is actually possible for the person pulling the prop through to bend a rod during that process itself. In other words, it does not always have to be a case where oil (or fuel) is left in a cylinder and then the rod gets bent during an engine start attempt. It is actually possible to BEND THE PISTON ROD while you are actually pulling the prop through by HAND. There is enough leverage advantage due to the length of the prop itself, that a person pulling the prop through can actually cause the damage him (or her) self.
Many new owners of these aircraft do not appreciate this fact and when they pull the prop through, they do so rapidly and pretty much just yank it around. Actually as you bring the prop up through each engine compression stroke, you have to be very careful of what it feels like, and this can only be gained with practice.
During winter starts when the oil is thick, I personally have to be EXTREMELY careful when pulling the prop through, and sometimes I just say to heck with it and pull the lower spark plugs out and let it drain for an hour or so even before pulling it through at ALL.
Intake drains are essential. Not only do they allow oil to come out of the intake tubes, the drain kit also makes it darn near impossible to have a hydraulic lock from over-prime. Why? Because when you prime the supercharger, the excess fuel runs right to the bottom and then out the intake drains.
When I prime my engine, I ALWAYS leave the intake drain kit valve OPEN so I can watch the excess fuel run out that drain. If it does NOT, then I know the intake drain is clogged up with oil and extreme caution is then required!
If you do not have an intake drain kit, then you have to follow the proper checklist which calls for removing not only the lower spark plugs, but also the intake drains themselves! The lower intake tube have screw out pieces that allow you to get the oil out. So especially with an engine that has not been started for a long time, you really need to pull the lower rear plugs, pull the intake drain plugs (if you do not have the optional intake drain kit installed) and AFTER you do all that THEN start pulling the prop through.
Since this was not done with your engine, it is likely that either you accidentally bend a rod while pulling the prop through initially (because the spark plugs were not pulled first and the cylinders allowed to drain), or as you mentioned yourself, the oil was in the intake tubes and got sucked in and caused the hydraulic lock., Again, there are drains in the intake tubes that should have been removed to allow them to drain first.
What can make this even worse is if you pull the prop through (without draining the cylinders by pulling the lower spark plugs & intake drain plugs) then feel it stop moving and then reverse rotation and pull the prop through BACKWARDS. If you do that, it is highly likely that oil will be pushed back into the intake tubes once again setting you up for a disaster.
This is one of the real dangers of these engines and I am sorry that you had this happen to you and I am writing this to make sure you totally understand how to keep it from happening again.
Best Regards,
Mark Bitterlich
From: Thomas McKeon
Sent: Thu 3/14/2013 6:36 PM
To: yak-list(at)matronics.com
Subject: RE: hydraulic lock
Please send me the photo's of the hydraulic lock. Not too long ago I hydraulic locked my engine. I pulled the prop through multiple times after over a month of not flying. It still locked up. I do not have an oil drain kit, and I'm told oil from the intake valves caused it.
Tmckeon79(at)hotmail.com (Tmckeon79(at)hotmail.com)
From: richard.goode(at)russianaeros.com
To: yak-list(at)matronics.com
Subject: hydraulic lock
Date: Thu, 14 Mar 2013 19:21:01 +0000
A number of people have asked for the photos I wrote about, and they will be sent out tomorrow. The reason for not posting them directly was that I was under the impression that posting photos wasn't permitted on the Yak – list!
Anyway it is quite spectacular – the connecting rod failed, but the engine went on running for another 20 minutes until landing. The forces were so great that even the master rod was bent, which I have never seen before.
I would say that you cannot underestimate the risk of a hydraulic lock, particularly with an old engine and an oil pump check – valve that is worn/sticking and allowing oil through the oil pump into the engine.
It is also worth saying that we have recently received an engine that was hydraulic locked with fuel, in this case just a bent rod but clearly serious over – priming!
Richard Goode Aerobatics
Rhodds Farm
Lyonshall
Hereford
HR5 3LW
Tel: +44 (0) 1544 340120
Fax: +44 (0) 1544 340129
www.russianaeros.com
[quote]
rget=_blank>http://www.matronics.com/Navigator?Yak-List
ttp://forums.matronics.com
=_blank>http://www.matronics.com/contribution
et=_blank>http://www.matronics.com/Navigator?Yak-List
p://forums.matronics.com/
blank>http://www.matronics.com/contribution
[b]
| | - The Matronics Yak-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Yak-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
