View Full Version : Ney Nozzles

04-15-2010, 04:52 AM
Has anyone have any experience or has experienced any problems with the Chuck Ney Nozzle installed by STC in a O-320 Lycoming? Has anyone noticed a difference? I have the nozzles but don't have a preoiler? Looking for opinions good or bad? Seems to me they are robbing to much oil pressure? Has anyone had them installed recently? Thanks

04-15-2010, 09:20 AM
I have the nozzles, but only have ten hours on the engine so I don't really know if they are good or bad. I haven't noticed any issues with oil pressure as I am able to run in the 70's. What is you oil pressure doing?

The holes in the nozzles are quite small so I don't think they could deduct much from the system capacity, especially since the oil pump in O-320's is also used in O-540's.

04-15-2010, 10:22 AM
We have only been able to get the oil pressure up to about 45. Cranked the PRV in all the way and no change. After the temperature starts climbing, it drops to about 38. Stopped engine at that point. Have eliminated everything but the nozzles. They were installed in 1995 so I'm not sure what is going on. Calling a case guy! I just hope they did not put the wrong nozzles in or something. Or actually I do hope then I would know. Maybe they are for a bigger engine or something. Thanks for your help.

04-15-2010, 11:38 AM
That's interesting. Did you remove the PRV and check if something has prevented the ball from seating? It would also be good to check the spring and determine if it's the correct one. I think Lycoming made three different springs. Here is a reference to it: http://www.sacskyranch.com/eng26.htm
Are you looking at oil pressure in the cockpit, or have you also tried measuring with an external gauge for comparison? Perhaps your oil press/temp gauge is defective? One other option could be a nozzle fell out. The only way to determine that would be to pull a jug and look around with a fiber scope, but I would think if that were the case you'd have a difficult time even getting 45psi. Perhaps a call to Chuck Ney may help: http://www.chuckneyent.com
Do you have a remote oil filter system? If so, make sure the lines are not reversed.

04-15-2010, 11:52 AM
We just split the case yesterday. Everything has been checked and double checked. Ney says it can't possibly be his nozzles and we have nothing left to check. We hooked another new gauge directly up to the engine and it read exactly as the one in a cockpit. New adjustable PRV had no effect. Has purple spring. Seat is fine. No remote oil filter just the old type screen. We were pretty sure we were looking at a bearing clearance issue until we split the case and everything checks out. I'm pretty sure we are going to take the nozzles out and plug the holes.

04-15-2010, 12:16 PM
Very puzzling. What type of oil pump body do you have. Two types exist, one with a pipe plug in the end and one without. Perhaps that plug is missing if that type is installed? One last thought may be the pipe plugs on the back of the case that plug the oil galley on each side of the cam; are both of those present? I can't imagine it's the nozzles causing the issue. Did you check for any blockage in the accessory between the pump output and the PRV; for that matter, the intake to the oil pump? Sounds like you've checked everything.

04-15-2010, 12:36 PM
Yep! Checked it all. Had the SL78528 oil pump body with the hex plug and the extra oil galley drilled in it. Did not like that set up because I don't have a fuel pump so put on the 78531 Lycoming body that does not have the hex or the dilled galley. The gears are matched and the 1/8 hole was drilled to lub the impeller. Checked the entire system with air for obstructions etc. Nothing. All clear. Quite a bit of air came out of those nozzles though. This is very frustrating because we have checked everything! All the galley plugs, the pickup tube gasket the plug in the bottom of the accessory case. Everything! But we are still looking.

04-15-2010, 04:49 PM
on phone with Chuck Ney
Check the Acc case for lube hole on rotating shaft.
Went over problems and attempted cures prior to tear down.
Chuck says it is NOT the nozzles.

look very closely at the oil hole added for the rotating shaft of the oil pump.
See Lycoming Service Instruction 1341

Chuck said he has found more than one of these that were drilled wrong.
The problem found was the oil was(if I understand correctly) pumping down the drilled hole to the hollow shaft back to the low pressure side of the pump.

Expect Chuck to join SWPC and chime in soon.


04-15-2010, 05:38 PM
Well thank you Charles. My only problem is that we have checked everything and it came down to two things. Either the bearing clearances or the nozzles. I guess my problem with the nozzles is that I don't know much about them. I was thinking wrong size holes/squirts or something like that. I'm certainly not badmouthing the installation or anything like that. I'm sure tons of research and experience went into the STC. They were installed in 1995 and I was trying to see if someone might have had a problem with an older installation as opposed to a newer one. If it is not the nozzles then I am really down to a crack or something wrong with the yellow tagged crank or the yellow tagged case. Chuck Ney sold the mechanic the case and installed the nozzles. Aircraft Specialties did the crank. Both a reputable businesses so I'm at my wits end. The case was line bored by Ney also. We did look at the 1/8 hole that was drilled to lube the impeller shaft. We measured the angle and the depth and it is exactly as the book says. I'm most likely going to send the case out complete with crank and see what someone can find. I cannot afford to send the entire engine out and have it redone. Replacing new parts with new parts does not make any sense to me and my wallett. The cylinders have 0 time on them. The cam is brand new as is most of the internal parts. I have two experienced mechanics that are stumped also. I really wish I had found a bearing issue! I really appreciate you guys and your efforts on this. Many many thanks!

04-15-2010, 05:53 PM
checking email and Priv Messages
Will be good if not Great if Chuck chimes in personally.
let me know when your available for phone

04-15-2010, 05:58 PM
Say NHPacer
Can you take a few images and post?


04-16-2010, 09:14 AM
Sending case and crank out. Thanks all for your input. This is beyond me and I'm sure they can find my problem and get it fixed for me. Can't wait to get flying soon! Blue Skies, we had snow this morning. Some accumulations but not too bad! Life in New England I suppose!

04-16-2010, 09:21 AM
One last question. I noticed you have venturies on your airplane. Does your engine have the vacuum pump adapter pad and shaft installed? If you have a cover on the adapter pad, but no drive shaft installed, that may be your ticket to low oil pressure.

04-16-2010, 10:02 AM
You are correct, no vacuum pump and we did put a plate on but he did put the shaft and gear inside before putting the cover plate and gasket on. We also verified that when we took the accessory case off. Crossing my fingers that I don't have to buy a crankshaft! I don't mind buying a case but a crank will hurt the wallet! LOL

04-16-2010, 10:21 AM
When the case was line bored, was it upgraded to accept the thicker, more modern O-320 bearings for the crank journals? The long main bearing at the front doesn't change for this mod. I don't have the p/n's, but there is a substantial difference in bearing thickness. It is possible the wrong bearings could have been used? I would think quite noisy during the engine run with gear lash and pounding. Out of suggestions now.

04-16-2010, 10:31 AM
You have probably done this all ready but have you checked the surface that the PRV ball seats on. This surface can get eroded by oil flow and not look damaged. A friend with a Vag send his C-90 out for overhaul because of engine damage due to low oil pressure. When the engine came back the oil pressure was no better. It turned out to be the PRV seat surface. Even compressing the spring all the way to solid will not increase the pressure if this is the problem

04-16-2010, 10:37 AM
Reading all these posts on a oil pressure problem jogged my memory, My dad overhauled a O-290- D2 years ago and put in a new oil pump body along with all the normal items. We fought low oil pressure from the git go. Tried new springs, washers( before adjustable oil pressure bypass valves), nothing helped.Decided to pull it apart and look. What we found was the new oil pump body had a slight warp in it we only discovered it by noticing a really clean streak on the Accessory Case below the pump body where high pressure oil was washing the case wall. don't know if this would relate to a O-320 but it was hard to detect it and we felt really lucky an extra pair of eyes spotted it.
Good luck, Mikey

04-16-2010, 04:02 PM
Thanks MrWayne. That is one of the things the case shop will look at. It was machined in and has not run for more than a half hour. They are going to verify the alignment of the bypass seat and the boss to see if the ball is seated correctly. We also put on a new oil pump body because we did not like the one with the extra oil galley drilled in it. It was hard to tell if the surface of the case properly covered the hole and since there is not gasket between the pump and the case, we felt that since we don't need the hole, then get the body that does not have it. The only differnce between the 78528 and 78531 body is the extra oil galley for the fuel pump and the extra hex plug in the side. I did not need either so I put on the 78531 for a more solid fit. The engine ran beautifully smooth and was not making any metal or noise to indicate a bearing issue but I will let the case shop do their thing. mjlossner what you and your father found on the O-290 was what I thought was originally wrong wityh my engine. I put on the new housing and a new adjustable PRV and was sure that was my problem! Wrong. Still having the problem. But thanks anyway. We are all on the same page.

04-19-2010, 03:47 PM
I have about 300hrs. on Ney Nozzles in my Pacer, with Chuck's straight bore cylinders. It feel like the engine uses less power to wind-up, it starts easier and runs smoother.

04-20-2010, 04:32 AM
Thanks for the feedback. I jhope this is my engine sometime soon. This has been very frustrating for me.

04-20-2010, 10:24 AM
Too bad I can't mail you a beer, you need one! I hope you get good news back soon!

04-20-2010, 05:57 PM
The grill is fired up and I'm pickling myself as I type. Thanks for the offer. If you could mail me a beer, I'd ask you to mail me some oil pressure too! LOL Sent the case out today! Will partake of many until I get some news.

04-30-2014, 09:10 PM
I was curious to see if this was resolved. I had an interesting experience with low oil pressure following overhaul of my O-290 D-2. Here's my story.... Could not initiate oil pressure turning prop by hand or with starter (with spark plugs removed). Zero-NADA. I had NEVER had this occur with any engine, and I meticulously put this one together myself using a new (serviceable) accessory housing that included the vacuum pump pad and oil cooler ports. Checked everything north of the crankcase and accessory housing - no indications of anything out of place. Oil and air bubbles would ooze from the oil cooler port exit the pump and then the oil would slowly drain back- faster than I thought it should. Pulled both mags and looked for something obvious - nothing. Pulled the engine, removed the oil sump and accessory case. Found nothing obvious. Had already rechecked oil pump and component part numbers. Rechecked the installation of the pump and oil pick up tube.

Nothing looked out of place, scratching my head and everything I had that I could scratch. For some reason, I decided to blow on the oil pick up tube, like I was playing a trombone. WAALAAAH! A small oil bubble would appear at the oil pick up tube flange at the accessory case. Rechecked the torque of the two bolts - on the money. Removed both bolts securing the flange.... and there it was. I had cleaned the oil pick up tube extensively prior to assembly, but my lying eyes missed a small piece of the old gasket that was still on the flange. It was enough to allow the pump to suck air into the pump. I scraped it off, brushed with the wire wheel, and then straightened the flange. Reinstalled, back together, and putting out 50 PSIG with the starter. Back in business.

I was surprised that I missed this, when cleaning and installing the pick up tube. My vision isn't what it used to be, as my 2x glasses are a must at close range. Just thought I would share if anyone else has had a similar problem.