|
View Poll Results: What kind of motor oil do you use? | |||
30W | 104 | 50.98% | |
10W-30 | 59 | 28.92% | |
10W-40 | 30 | 14.71% | |
Detergent | 47 | 23.04% | |
Non-Detergent | 4 | 1.96% | |
Natural (as opposed to synthetic) | 48 | 23.53% | |
Synthetic | 9 | 4.41% | |
Motorcycle Oil | 4 | 1.96% | |
SG Grade | 6 | 2.94% | |
Some Other Variation | 12 | 5.88% | |
Multiple Choice Poll. Voters: 204. You may not vote on this poll |
|
Thread Tools | Display Modes |
#76
IP: 107.0.6.242
|
||||
|
||||
We have had other members report that oil pressure increases with time and temp increase after start up. I have tried to make sense of this because it is counter intuitive to my understanding and experience that viscosity decreases with temp and hence pressure should also decrease. One factor that keeps coming to mind is the nature of the oil pump intake. The "bottleneck" is the 1/8" NPT 90 degree street ell coming right off the oil pump. Since that fitting is a casting, it's cross sectional area is subject to the irregularities of the casting process. Even a small burr in the oil stream could have an influence on flow especially at cold temperatures. Because of the foregoing "theory" I have modified my oil pump to use a 1/4" NPT fitting. The difference in oil flow was impressive and could account for the big pressure differential I live with between start up and cruise. I live with it and enjoy the (relatively) massive flow and pressure increases as well.
Last edited by hanleyclifford; 02-14-2016 at 09:38 PM. |
The Following User Says Thank You to hanleyclifford For This Useful Post: | ||
GregH (07-27-2017) |
#77
IP: 107.0.6.150
|
||||
|
||||
What's with all the dotted lines in the posts lately?
|
#78
IP: 98.171.162.64
|
|||
|
|||
Quote:
This is why it is recommended that oil pressure be adjusted when the engine is fully warmed up at cruise RPM. TRUE GRIT |
#79
IP: 108.79.1.46
|
||||
|
||||
I could have sworn I saw higher pressure with lower viscosity oil and it seemed counterintuitive to me also.
I assumed lower viscosity = lower pressure = higher flow rate but my observation (as I remember it) was opposite, pressure wise. I don't really worry about it as I never see pressure drop below 20 or so at any time. not sure how we could measure flow rate anyway
__________________
john '77 catalina 30 #783 the only way to be sure is to make sure |
#80
IP: 108.79.1.46
|
||||
|
||||
Mo, same with me. I try to be in around April 15, and water temps are high 30s to low 40s. Got a big fur hat and an Irish wool sweater for those days.
__________________
john '77 catalina 30 #783 the only way to be sure is to make sure |
#81
IP: 98.171.162.64
|
|||
|
|||
I Assume You Have An Electric Gauge?
Quote:
TRUE GRIT |
#82
IP: 132.147.29.249
|
||||
|
||||
I see them in IE but not in Firefox.
|
#83
IP: 132.147.29.249
|
||||
|
||||
My current engine starts out high - 60 PSI - and then quickly falls to 40 as it warms up.
My last engine started out at 20 and slowly built up to 40 over 20 minutes or so. My only thought is restrictions of some kind or a bad pump = thick oil not being pumped very well. Lack of restrictions equals the usual cold oil is thicker which gives higher pressure. Quote:
|
#84
IP: 107.0.6.242
|
||||
|
||||
Quote:
|
#85
IP: 107.0.6.150
|
||||
|
||||
This thread has some useful info: http://www.moyermarine.com/forums/sh...=9581#post9581
|
#86
IP: 108.31.90.116
|
||||
|
||||
They're ToolTips, another great feature our Admin has set up. Commonly used, but sometimes obscure, acronyms get underlined. Hover over them with the mouse pointer to see the the full text for things like UHS, IMHO, and IIRC.
Interesting. I see them fine in Firefox (on a Mac).
__________________
@(^.^)@ Ed 1977 Pearson P-323 "Dolce Vita" with rebuilt Atomic-4 |
The Following User Says Thank You to edwardc For This Useful Post: | ||
GregH (07-27-2017) |
#87
IP: 107.0.6.150
|
||||
|
||||
Quote:
|
#88
IP: 24.42.116.94
|
||||
|
||||
After my partial rebuild early spring 2015 & having done at least 6 serious lil system flushes, I adjusted the oil pressure bypass in because i was seeinf pressure holding at about 25 - 30 lbs. After the adjustment I saw 35-40 lbs. Then I drained my last clean oil , something cheap and common, 10-30 and filled her up with 15-40 Rotella. Did a few more odds and ends which allowed the engine to cool down and give her a start.
The start up pressure shocked me at 70lbs right off the bat. Then quickly drolped to 60. I thought I waz going tl need to adjust the.pressure down. However, after warming up the pressure dropped back to hold.between 30-40 under normal opperation . Obviously 60-70 is way too much but Im now wondering if opperation 30 & 40 is ok.
__________________
Bill 1974, Tartan 30, Unchained Melody www.CanvasWorks.US |
#89
IP: 161.213.49.150
|
|||
|
|||
Mr. Bing
Here is what Don M. recommends on page 5-4 & 5-5 of the Moyer Manuel. Dress up the seat of the regulating valve every 5 years or more often if necessary. Did you dress the seat as part of the rebuild? Then readjust the OP to ~ 50 PSI cold idle then (more importantly) 40 PSI with the engine warmed up at your cursing RPM. And on page 5-4: "As long as the OP at idle is ~ 1/2 the OP at normal cruise all bearings as well as the oil pump are in reasonably good condition." Hope this helps. TRUE GRIT Last edited by JOHN COOKSON; 02-17-2016 at 02:37 PM. |
The Following User Says Thank You to JOHN COOKSON For This Useful Post: | ||
GregH (03-03-2018) |
#90
IP: 108.79.1.46
|
||||
|
||||
I replaced all the engine wiring for the 2014 season so I know that is good.
I'm thinking the only way to be sure of correct oil pressure is to install a new gauge and matching sender. Catalina Direct has a nice oil pressure gauge which matches the fuel gauge I installed last season, but the sender is metric thread. Will any sender work?
__________________
john '77 catalina 30 #783 the only way to be sure is to make sure |
#91
IP: 107.0.6.150
|
||||
|
||||
Quote:
|
The Following User Says Thank You to hanleyclifford For This Useful Post: | ||
Administrator (02-17-2016) |
#92
IP: 161.213.49.150
|
|||
|
|||
Quote:
You answered your own question. The sender and gauge must be matched (ie from the same manufacturer)for accurate readings. That having been said some sending units and gauges are interchangeable because they have the same parameters. If you know the manufacturer of the sending unit and gauge you might be able to cross reference. TRUE GRIT |
#93
IP: 137.200.32.54
|
||||
|
||||
Not exactly.
If the sender and the gauge are both the same range and both the common 240-33 ohms, then they should work fine together. I went through 3 gauges on my old engine with the original sender and they all worked fine. Nothing wrong with getting all new though if you are not sure what you have. Remember 33 ohms is full scale, so if you have a 100 PSI sender and an 80 PSI gauge your readings will be off. Quote:
|
#94
IP: 107.0.6.242
|
||||
|
||||
Nothing wrong with using an electric gauge and sender but I would never rely on it alone. Keep a second, direct read gauge hooked up somewhere on the engine for comparison purposes.
|
#95
IP: 73.255.216.151
|
||||
|
||||
A mechanical gauge can be mounted most anywhere. There are tubing kits 15 feet long available.
I hooked one up on my VW bus. It was on the dash. I bled the line and had oil right at the gauge. It was very sensitive, and would go up and down when I shifted. |
#96
IP: 107.0.6.242
|
||||
|
||||
FWIW
I had a mechanical gauge on the panel for a while fed by a long plastic "kit" tube. The plastic hardened and deteriorated over time and broke off right at the ferrule. Lesson learned: use copper for the run to the gauge.
|
The Following 3 Users Say Thank You to hanleyclifford For This Useful Post: | ||
#97
IP: 71.239.241.153
|
|||
|
|||
I have virgin early model A4 and have always had "mechanical" oil pressure gauge with connected copper tubing w/compression fittings. Gauge is on cockpit wall exposed to weather during the season. Am on my 3rd gauge in 42 years with same 3+ ft tubing [tee'd off to OPS]. Used Stewart- Warner gauges, sometimes a little hard to find "mechanical" type. FYI, engine is on slight aft tilt and have always used 4qt name brand 30W or 10-30W w/ 1 bottle of STP. Oil pressure is about 35psi at start up, 30+ psi at cruise and around 20psi at idle. Once in a great while I get a very small leak with this set up and a fitting needs a little tightening. I believe you get a accurate reading with the mechanical gauge vs electrical and matching the right sending unit.
|
#98
IP: 134.134.139.74
|
||||
|
||||
Apologies for resurrecting an old thread.
Quote:
I sent off the oil pump to MMI (courtesy of the Amish ones ) for testing and the result are it landed on the 'correct' side of the bell curve. But looking at Hanley comments about reducing the inlet restrictions and the 1/4" NPT street Ell... has anyone else done this? BTW, when I build my first custom car, I did a "high volume, standard pressure" oil pump on the blueprinted engine. It has been a great motor, no leaks and still lots of pressure (75 PSI cold, drops to 40 PSI hot at idle and 50-60 PSI when running through the gears. Is a similar performance (but not exact PSI) possible on an A4? ... this is coming from a person after two A4s with low oil pressure after 2-3 hours of cruise.
__________________
Thanks, Ron Portland, OR |
#99
IP: 137.103.82.227
|
||||
|
||||
Quote:
You may want to look at an oil temp gauge and an oil cooler. The temp gauge is on my list and maybe a cooler depending on what I find. |
#100
IP: 134.134.139.74
|
||||
|
||||
Joe--
I wish had your oil pressure, then I would only be dealing with a bit of blow-by. I manage that by having vent cap with a hose connection that I put in the bilge blower inlet. Looks similar to: https://www.napaonline.com/en/p/BK_7...oaApyvEALw_wcB I have 80PSI cold when warm up the engine and drop to 40-45 in 5 mins. When running for more than hour at cruise I'm at 20 PSI. At idle when I'm maneuvering into the slip, I'm at so low on oil pressure that I'm worried about the OPSS killing the engine. Now back to the question: Has anyone else done the larger 1/4" NPT Street ell into the oil pump?
__________________
Thanks, Ron Portland, OR |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
What kind of paint to use on the engine block? | Rick_Powers | General Maintenance | 2 | 01-24-2009 09:56 PM |