Where does your oil guage needle ride?

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My 89 has a big hash mark on the right and a big one on the left. Between them are seven little hash marks - no numbers. My needle rides on the third small hash mark most of the time, but drops down to the second at idle. I've got no clue how much oil pressure that is, but all the Cummins manual says is that if the red light is not on, everything is OK! How do you boost oil pressure on Cummins? Is there a relief spring you can shim like on a small block Chevy?

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http://coffeewithJesus. homestead.com/web1.html 89 1-ton, Amsoil System 3000 5-30,K&N air filter, cleaned-up exhaust, Dynomax straight-thru, rebuilt pump, 12cm wastegated turbo, thermostaticly controlled twin 14" electric fans, intercooler, modified 518 OD transmission, Gear vendors OD controler, R-134, louvered fenders, 93 aftermarket smoothe grille; 78 35'Avion, 93 Lance 900 slide in with generator and power jacks. Jesus saves!

 

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Down the road, my '91 rides mid-scale, at idle it depends on conditions. Idle after a long heavy pull in hot weather might be barely off the lowest part of the scale - but under city driving in moderate temps, about quarter scale. These meters are pretty crude, and don't really give much more than a rough indication of pressure - but unless yours spends LOTS of time down around the bottom of the scale, I wouldn't worry much about it, and would look into a new sending unit as first option. Trying to modify pressure would be the LAST thing I would fool with until I was dern certain there was a problem, and even THEN any oil pressure problems aren't likely to the in the pump itself...

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Early '91 250, 727 AT, 307 rear... Banks Stinger exhaust, intercooler... US Gear OD... MORE than a match for every new PS Ford encountered so far...

 

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The only way I know of to raise oil pressure in your CPL804 (1989 engine) is to replace your oil pump with one from a CPL1351 (late 1991,1992,or 1993). The oil pump in these engines is geared a little quicker giving 16% more volume. Also if you purchase the relief valve and spring to match you will not have trouble dumping the extra when the engine is cold. The newer engine also has bigger piston cooling nozzles and because you will not be changing these your result will be higher oil pressure. This seems to work well in engines that are biginning to get a little tired. Also if you have raised your power muchit wouldn't hurt. (personal opinion). Hope this helps. John

 

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that helps; where is the oil pump located? do I have to yank the engine? I have noticed that with my Perma Cool fans on,the oil pressure goes up significantly! If I stick a graduated meter on it, what poressure should I be reading at road speed?

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http://coffeewithJesus. homestead.com/web1.html 89 1-ton, Amsoil System 3000 5-30,K&N air filter, cleaned-up exhaust, Dynomax straight-thru, rebuilt pump, 12cm wastegated turbo, thermostaticly controlled twin 14" electric fans, intercooler, modified 518 OD transmission, Gear vendors OD controler, R-134, louvered fenders, 93 aftermarket smoothe grille; 78 35'Avion, 93 Lance 900 slide in with generator and power jacks. Jesus saves!

 

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Hey Simpson, Why not just install a gauge?? My factory (dash) oil pressure just started falling off one day while driving scaring the #@$* out of me!!! I gingerly brought it home, went to the corner NAPA store and bought a small gauge cluster. I now have a Mechanical Oil pressure and Water temp gauges mounted under the radio by the ashtray. Figured out that I had a bad Oil pressure sending unit. I have not changed it yet, I'm to cheap!!!! I just use the mechanical gauge for pressure indication. I tee'ed it in right at the factory location, just below and behind the VE pump. This was a very simple install. On the water temp I removed a pipe plug right by where the top water hose connects to the thermostat housing. Again very easy.

My oil pressure at start up in the morning is 80 psi, right up against the bypass spring. After several miles of driving and warming up it settles back to 45-50 psi at 70-75 mph cruise. On a Hot day and pulling a load it idles at about 28-32 psi, normal traffic driving 30+ psi. Hope this helps.

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92 Ext. Cab, Auto trans. , 3. 54 Non-LS, Isspro Tach and Pyro (pre-turbo), 210,000+ miles, straight pipe,old and abused but still running strong!!!!

 

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That helps a LOT! Thanks!

 

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Your oil pump is behind your front gear cover. To change your pump you will have to remove, radiator, fan group, front crank balancer, then the cover. The pump will be on (facing your engine) bottom left. You will have to remove 4 bolts holding it. That's it. No removing of oil pan or suction tube assembly. If you wish to change your pressure relief valve there is a plug next to the top of your oil filter(19 mm), remove and the spring and valve are there. Reguarding your questions about pressure, I long ago removed the factory sender and installed a Stewart-Warner mech. , however as I recall each small mark was approx. 10 PSI. The Cummins line on this seems to be. With warm oil, at idle- 20-30 PSI (absolute min 10 PSI), at 1600 RPM 40-50 PSI, at 2000 RPM 40-55 PSI, at rated RPM 40-65 PSI. This is the latest data I have. I received this from Cummins on Oct. 14,00. So as you can see, this data is not that old. Some of the older information I had said you were allowed to go as low as 30 PSI at rated RPM. but I guess Cummins had a change of heart. I personally believe if one is increasing power from stock it may be a thought to try to increase oil pressure to at least the midrange of this Cummins data, in order to carry the extra load you will be exerting on rod and main bearings. (personal opinion only) Hope I have been of some help. PS. If you are seriously thinking of doing this, and especially if you have increased power when you remove the crank damper you may wish to consider replacing it with one to withstand the stronger vibrations. The Cummins part # 3924435. This is the one used on our engines when rated above 215 HP. Hope this is of some help. John Krmpotic

 

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The oil pressure guage on my 89 reads really low somtimes, and other times it reads around 1/4 to 1/3 up the scale. I too was scared the first time I saw it just bearly off the first line at highway speed. I immediately changed the sending unit, but this did not help either. After a while I learned to ignore it, just like the POS factory ammeter in the dash that always reads in the same position.

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89 D-250 LE 5 speed 3. 55 Limited slip, K&N, straight piped, Boost/Pyro. & 16cm2 215K and still going. 91 W-250 5 speed, 4. 10 Limited slip, 16cm2, 6" Skyjacker lift, RS9000, Dump bed, 18K original mi.

 

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Thanks guys; I've got a spare oil guage laying aroiund. I guess I'll install it. Now to tackle that runnning light problem.