The Diesel Stop banner
1 - 16 of 16 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter · #1 ·
Is the oil pressure dash gauge a fixed value or can it be run off a variable sending unit? OR does it run thru the ecm as a go/no go type and I would have to "T" at the sending unit?

If variable sending unit capable does anyone know or have a part # or a compatible part from another engine. Or can I disconnect it and put an aftermarket gauge on it?

Thanks
Larry
 

·
Registered
Joined
·
5,552 Posts
The oil pressure sensor is only a switch - on or off. Also, the gauge is only on or off.

IMO it is not worth the effort to make the dash gauge an actual gauge. You can however install a real pressure sending unit in place of the switch and run the signal to a new (aftermarket) gauge. That said, there is a test port on the side of the oil cooler specifically for that.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #3 ·
The oil pressure sensor is only a switch - on or off. Also, the gauge is only on or off.

IMO it is not worth the effort to make the dash gauge an actual gauge. You can however install a real pressure sending unit in place of the switch and run the signal to a new (aftermarket) gauge. That said, there is a test port on the side of the oil cooler specifically for that.
Thanks. When I change the oil cooler, I'll look for the test port and install an aftermarket gauge. I've got a Scangauge II on it right now and my Delta's are running about 15-20 at 70mph. 10-15 in stop and go. Coolant temps 175 to 180. General maintenance stuff I'm doing in APR. Flush out coolant and change thermostat, Water pump (have both new, metal impeller), belt, Alternator, (slow to come up to 14.2 and then fluctuates wildly from 13.2 to 13.9 mainly.) and 7.3 Fan clutch mod. All grounds to be cleaned and ohm'ed out. FICM shows 48.3vdc consistantly. Trans temps are consistant @ 155. Got it Oct. 2019 with 280K, now 309K. It's been studded (April 2017), had a full delete on cooler (had to replace for Md. Emissions) new egr cooler is plugged and welded so it's deleted but visually installed. Getting 20-21 on interstate @ 65mph on cruise. 70mph about 19. Towing my 5500# 25ft Sunline it gets 12.5 to 14 depending on hills or flat @ 60. Temps don't go up appreciably except Trans which sits about 185* when towing.
15W40 T-6 Shell Rotella. Next Winter I'm gonna try 5W40 for easier starting as below 45* I have to use block heater or it's extremely hard to start. Rev-X in Oil, Lucas in Fuel Tank.
 

·
Registered
Joined
·
5,552 Posts
Maybe your coolant sensor is off a little ..... normal coolant temps are around 192. Either that or it is your thermostat.

Always good to validate the temperature sensors before condemning an oil cooler.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #5 ·
I figure to replace thermostat, as it takes a good 20 miles for it to come up to 175. One time tearing it apart is enough. I can pull a small block from a 63 impala in less time than opening up the 6.0 for water pump, thermostat, alternator and I oil cooler.
 

·
Registered
Joined
·
5,524 Posts
I figure to replace thermostat, as it takes a good 20 miles for it to come up to 175. One time tearing it apart is enough.
That is too long and too low of a temp. Specs for the t-stat - begins opening @ 188°-196°F and is fully open at 219°F. During relevant diagnostics I see coolant temps from 195° to 210° on a road test. Yes, I would replace the t-stat and re-evaluate.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #7 ·
Replaced T-stat and coolant sensor. Old T-Stat was about 3/4 open and STUCK. Recycled old coolant (radiator replaced 2 years ago) filtering thru Chamois, and took it on a 20 mile test run. Temp came up to 190-191 and stayed there within 4 miles of 35-40mph roads/hills. EOT went to 205 and stayed there on normal highway. Once I got in the hills around our place (and there are some 3% 3 mile hills on I-83) EOT rose to 209, but came back down to 205 by 1/2 way down hill. Coolant temp NEVER wavered from 190-191. Never heard Fan engage electrically but that's not a problem as I'm putting in a 7.3 clutch. Had to button it up as Family problem requires use of the truck.

EGT arrived. I'll mount the gauge and run the wires, but let the shop drill and tap the manifold.

Oil Cooler in hand, as is new metal impeller Water Pump, and Alternator/Belt. RV season around the corner and the old lady is getting antsy. :D
 

·
Registered
Joined
·
5,552 Posts
Earlier I suggested that you determine if the coolant and oil temperature sensors are accurate. Have you done that? After sitting for 12 to 15 hours, they both should read within a degree of each other (ie read ambient temperature). So should the transmission temp sensor and the two IAT sensors.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #9 ·
Per the Scangauge II when I Key On Engine OFF All temps are within 2*F after an overnight without the block heater plugged inm I'm doing preventive maintenance on it before towing season. Which is why Coolant sensor was changed. I'm keeping the old one as a spare in case needed. I only plan on opening this beast up once this year.
 

·
Registered
Joined
·
5,552 Posts
Sounds like they are all close enough.

What procedure are you planning on using for the coolant flush?
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #11 ·
Backflush thru oil cooler, back flush thru htr core, fill with distilled and restore, run a few days then drain, flush again,, fill with straight distilled, run a couple hours then drain again. Final fill with 50/50 ec-1 & distilled water.
 

·
Registered
Joined
·
5,552 Posts
The final fill with 50/50 won't work because you can never get the system empty (ie it will retain about 1.5 gallons of distilled water even with all the drain holes and hoses open). You will never get the entire system at 50/50 unless you fill with the concentrated coolant.

The best bet is to add 3.5 gallons of 100% coolant after the final run on distilled water, and then top off with distilled water. The entire system is about 7 gallons.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #15 ·
Changed the thermostat 1st and ran for 3 wks. Stant thermostat rated 190*F. Temps at 190-191 with EOT btwn 201 and 206. Just finished changing Water pump (impeller had a crack at the shaft, replaced with metal 100mm impeller pump , 7.3 Fan clutch with BPD adapter (I hate electric fans). New belt, 6.4 banjo bolts (lot smoother acceleration and less throttle needed for maintaining speed, doesn't feel like it's starving), 135A Alternator (now voltages float between 13.8 and 14.0 depending on accessory load). Drained, back flushed oil cooler, heater lines, and block. Block drains so tight broke 1st a 8mm hex socket, then with new socket, 4" extension torqued off. Gave up on block drains. filled 3 times with distilled, drained. Filled with Distilled and 2cups of Liquid cascade and distilled. Ran for a week. Drained and filled 4 more times with 25 gallons of distilled. on last fill Ran until HOT (191*F), let cool an hour and drained. Added 3-1/2 gal of Peak EC-1 and about 1 more gallon of distilled. Closed it up after chacking for leaks. Changed coolant filter. Now temps are holding 189-191 with EOT of 199-204. Looks like I might have to replace oil cooler soon. I'll try it with the trailer (25ft Sunline 5900# loaded) on my 15 mile(mostly highway) test loop and see what the delta's turn out to be. Concentration on Antifreeze is about I figure, 60-65% (265*F to 289*F) via my hydrometer. I can hear the fan kicking in and out when A/C is on due to heat being shed by the condenser. Might just save up a couple months and get the BPD oil cooler kit with the remote filter. If I'm gonna do it, might as well do it just once and have it over and done with.

Coolant temp and EOT Sensors are still within 1-2 *F of ambient temp after sitting overnight so they're still good. Noticed a lot less hesitation and rough idle when 1st started due to the banjo bolts (good sign!). Throttle response is smoother, and feels like there is an increase in power at a lower throttle setting. Original banjo bolts are very restricted, with a check valve that restricts probably even more. Warmed up it's now a lot smoother, and with lower throttle setting at given speed, mpg has gone up about 1/2 mpg per the scangauge. With the cost of diesel where I live at $3.19 and up, anything I can do to increase mileage is a bonus.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #16 ·
Got the new oil cooler in(updated factory unit). Old one was clogged up with sand and goo (unknown mileage on it). Back flushed as above AGAIN, running last batch of coolant thru another Chamois and adding more EC-1 to top off. Coolant is 62%/D.W 38%.

Coolant temps consistant between 188 and 191 with EOT of 194 to 197 @ 65 and veh unloaded. Pulling 7500# trailer in 95*/95%hum Coolant temp goes to 198-201 and EOT 206-210. EOT is slightly behind CWT as it should be. This is with a '97 7.3 mech. clutch, new 100mm Metal Impeller pump, and 190 Stant T-Stat. New Coolant sensor, Oil Pressure switch, and EOT sensor. All within 2* of ambient after cold soak overnight.

Ended up having to put a new Garrett direct replacement turbo in it as the unison ring slot was "L" shaped and the cam pin that the slot fits on was over half worn off, causing a good amount of slack and unison ring rocking back and forth. I've looked for the cam pin online but came up bupkus! Hate to toss a perfectly servicable turbo, but unless someone knows where I can get the unison ring actuator cam pin/shaft, it's history. New CAC tubes and rubbers (drivers side tube had small split in accordian area (plastic tube.). Replaced goofy looking Aftermarket Cold air Filter with a replacement WIX filter housing and snorkel thru the radiator support. Now it gets cold air! Did the downspout mod for the snorkel. Haven't added the EGT or Oil pressure gauge yet. (on the honey do list).

Anyway, truck is running very well, and I'm quite happy with it. Enough that I sold my '13 Yukon XL which we use for X-country trips. Yukon couldn't pull the trailer (geared too tall) otherwise it would have stayed. I went to Pensacola in July for my brothers funeral in the truck. Went down 81 to knoxville, chattanooga, birmingham, to P-Cola and averaged 21mpg @ 65 round trip. Seems that 62 to 65mph is sweet spot for mileage on this truck. Not bad for an essentially stock 3-1/2 ton brick running 3.73 gears. only real mod is the 4" banks exhaust.

Forscan showed Glowplugs 6-7-8 open. Got new motorcraft glow plugs and harnesses. Took my meter with me to dealer and went thru 19 glow plugs before I got 8 that metered fine. The rest were open. Needless to say the Parts Manager was almost as pissed at me for testing them at the parts counter, as he was at FORD.....but I wasn't about to make 2-75 mile round trips for glow plugs.

2 scangauge-II's daisy chained. Volts, CW, EOT, Tran temp on one, Boost, EBP, ICP, and VGT currently on other. All parameters for the 6.0 loaded and I can cycle thru running. Not quite ready to electronically tune (my stereo's all have tubes, my kids tell me I'm a Technology Neanderthal, lol) but monitoring is fine.

X-country trip next week to Az. On way back haul 4 tons of horse trailer and household goods in it to Mississippi for a family friend. Not going back across 40 thru Az and N.M I don't like the hills out of albuquerque (6-8% grade UP!) so down to Tucson and across I-10 to I-20 to Jackson Miss. Mostly all flat!
 
1 - 16 of 16 Posts
Top