 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
Tommy Walker
Joined: 12 Jan 2006
Posts: 442
Location: Anniston, AL 36207
|
 Posted: Thu Jun 26, 2008 3:44 am Post subject: Low Oil Pressure....Re: High Oil Pressure |
 |
|
I have the opposite problem. On the last flight, oil pressure was consistently around 30 psi. After landing, I checked the oil level and it was between the high and low marks. I cranked the engine and the oil pressure stayed around 30 psi. I have about 40 hrs on this oil and filter. I planned to change the oil/filter at 50 hrs.
I have another set of VDO gauges so I swapped the oil pressure gauge and cranked the engine again. 30 psi.
I have another 912 so I borrowed the oil sending unit and put it on the problem engine. I cranked the engine and the psi went to between 45-50 during 2000 rpm idle. I ran the rpm up to about 3000 and the oil psi was around 40, maybe a little more according to the analog gauge.
This is an almost new engine. It has about 60 hours on it. The oil pressure has declined from 60-65 at startup to the current pressure. Before, cruise pressure was around 40-45 psi.
I am wondering what the next step should be? I am using the Rotax oil filter from Lockwood Aviation and the recommended Mobile 1 oil. I plan to change the oil and filter today and check it out.
Any other ideas?
Many thanks,
Tommy Walker in Alabama
N8701 62 hrs.
[quote][b]
| | - The Matronics RotaxEngines-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?RotaxEngines-List |
|
_________________
Tommy Walker
N25A - Anniston, AL |
|
| Back to top |
|
 |
arno7452(at)bellsouth.net
Guest
|
| Posted: Thu Jun 26, 2008 6:07 am Post subject: Low Oil Pressure....Re: High Oil Pressure |
|
|
Try a mechanical gauge. I had same problem and it appears the problem is in the sender. Rotax senders are a little pricey.
With mechanical gauge, the psi was back to normal.
Ken Arnold
N701LK
[quote] ---
| | - The Matronics RotaxEngines-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?RotaxEngines-List |
|
|
|
| Back to top |
|
|
Roger Lee
Joined: 10 Jan 2006
Posts: 1464
Location: Tucson, Az.
|
| Posted: Sun Jun 29, 2008 5:47 pm Post subject: Re: Low Oil Pressure....Re: High Oil Pressure |
|
|
Hi Tommy,
Couple of things here. The VDO gages come in two models. One has an anti vibration cadmium ring around it and it cost $200+. The other exact VDO gage is the same gage it just doesn't have the anti vibration ring and it sells for about $40. Since Rotax has had some issues over the years with the vibration on the oil pressure sender I would remote mount it and use the $40 model. This is an approved modification from Rotax. If you have a Dynon system and a fuel pressure sensor for that I would highly recommend that gets remote mounted.
Now for the problem of the low oil pressure. To check to see if the sender is correct you can buy at the hardware store a few simple items and make a mechanical gage and see if the sender and the gage in the cockpit are correct. Checking the sender and cockpit gage with a mechanical one is the number one item to try and see where you need to look first. Use 1/8" copper tubing, a mechanical gage that goes up to 100psi. The oil pressure sender is a 1/8" NPT fitting. Bring the tubing out about 12" then add a tee fitting. This way you can put the sender back in line and check it against the mechanical one. Put the mechanical gage at the end of the 5' of copper tubing. 5' of tubing lets you bring the gage into the cockpit to compare.
A few months ago I had the same problem with an Flight Design CT and found a partial ground. The meter said it was grounded, but I found it was only a partial ground and when I added a test wire right to the ground it started to read in the cockpit as it should.
Does the pressure change with the the rpm. Does it go up and down? Partial ground problem. It may change some (normal), but if it is a partial ground it gets lower in pressure as you give it more throttle. Your 912ULS oil pressure should be between 40-55psi during normal cruise rpm's. It will be a little higher on start up, but then come down as it gets warmer. Some of the older 912ULS's ran higher oil pressure than the new 912's run. Rotax lowered the pressure. They said they were more concerned with volume over pressure.
Hope this helps.
| | - The Matronics RotaxEngines-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?RotaxEngines-List |
|
_________________
Roger Lee
Tucson, Az.
Rotax Instructor & Rotax IRC
Light Sport Repairman
Home 520-574-1080 TRY HOME FIRST
Cell 520-349-7056 |
|
| 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
