| len47merc | -- 03-21-2014 @ 4:44 PM |
|
Though the original oil pump in my '47 Merc 59 A-B is producing with 30 weight oil 70 psi @ start-up and after warm, 30 at speed/rpm/10-15 at idle and, while having it out of the motor for cleaning and rear seal replacement appears in excellent condition, I am being advised (by 'experts') to upgrade to an 8 BA oil pump as it reportedly generates better flow, particularly at lower rpms/idle. Can anyone confirm, refute, or otherwise weigh in here. I'm typically of the mantra if it ain't broke don't fix it, as well as (most importantly) stay original as possible. Appreciate all comments. Steve
|
|
| carcrazy | -- 03-21-2014 @ 8:35 PM |
|
I agree with you, if it ain't broke don't fix it. I had a '40 Flathead V-8 rebuilt and my mechanic suggested that I have the later 80 PSI oil pump installed. It turned out to be a big mistake. After 500 miles or so the rear main seal began leaking about one quart of oil every 200 miles. Anytime the engine was running oil was dripping from the rear main seal area.
|
|
| fla48 | -- 03-22-2014 @ 7:18 PM |
|
The oil pressure you are experiencing is not out of limits. Although I use 30 weight oil, many use 10w40.
|
|
| supereal | -- 08-10-2014 @ 1:26 PM |
|
An 80 pound pump doesn't create always greater flow, particularly if the relief valve under the front of the intake manifold is unmodified. If you don't have an oil filter on your flathead, but experience an oil leak at the rear main seal, reduce the crankcase fill to 4 quarts, instead of 5, and it will likely reduce the leak unless the seal or crank surface is badly worn. Remark the full level on the dipstick to show the reduced fill. Be aware that there are reports of serious problems with some imported oil pumps. We use Melling at our shop.
|
|
| len47merc | -- 08-11-2014 @ 4:18 AM |
|
Thanks supereal. Since this discussion back in March the decision was made, after my personal unsuccessful attempts to change the original rear seal with the motor still in the car, to pull the original 37K mile engine and go through it completely with all NOS bearings, valves - everything. The 78-year old owner of multiple 990+ scoring Fords who purchased an extensive inventory of original Ford parts back in the early 60's, and still rebuilds these engines, went through the oil pump as well with original bushings, gears, etc., basically returning it to new. With 30 wt oil the original rebuilt pump now pushes the oil gauge above 80# until warm and then holds a steady 35# at RPM after warm and 20# at idle. Sincere thanks for your follow-up supereal. Steve
|
|
| TomO | -- 08-11-2014 @ 5:06 AM |
|
if your pump is in good condition, and producing 80#pressure, I don't understand how a new pump producing 80# could produce better flow. The pressure is developed due to restrictions in the oil passages and the pressure relief valve. I would leave it alone and not fix what isn't broke. Tom
|
|
| EFV-8 Club Forum : | https://www.earlyfordv8.org/forum |
| Topic: | https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=16&Topic=7146 |