Can anyone tell me where the sensors/fittings are that I need to tap into ti install aftermarket gauges? It is for an 89 F-150 w/efi 302. The gauge set I have is oil pressure, water temp, and ammeter. Tthe Haynes manual is pretty vauge on the actual location. Any help would be great.

 

The oil pressure sending unit it just above the oil filter. You sould put a tee in so the old sending unit is still working or else you will get a check engine light. Expect leaks if you're not careful.

The amp meter will require splicing into the charging wire from the Alternator to the Battery. You will have to cut that wire then run one wire from one side of the cut to the gauge and another wire back to the other side of the cut from the gauge. Be sure your wire size is large enough to hand the all of the output from your alternator and to tape everything carefully; electrical fires are not fun.

The water temperature sending unit is the most difficult. I just looked at my '88 302 and about the only place to get into the water jacket is at the thermostat housing. You will have to remove the housing and drill and tap the blind hole at the top. You may need an adapter to fit your sending unit. And don't forget to buy a new thermostat housing gasket and some antifreeze.

Have fun!!!

Bob
'66 7 Litre, top loader, 3.25 Traction-lock, Sidewinder Intake, SCJ Exhaust
'88 F150 LWB 4x2, XLT Lariat, 302, 5 speed, 3.08
'99 Ranger, 4x2, 3.0, 5 speed, 3.73 posi

 

The locations directions that bsprowl gave you are correct. The Factory temp sender is on the intake manifold near the distributor. But if you want to leave that one alone. Then you can splice in a 1/2 inch pipe tee in the hot water line going to the heater core and then hook up the temp sender in the tee I did this on my 88 crown vic to trouble shoot a heater problem I was having on it. 3 yrs later it is still there and seems to work fine. The highest water temp in the engine is right at the thermostat houing this is also where the hot water going to the heater comes from also so I Feel that this solution gives an accurate temp reading.
Just my 2 cents worth.

 

Need to revisit the ammeter setup. Recommend you remove every wire from the battery side of the starter solenoid except the battery cable. Put your ammeter in between all the removed wires and the battery connection on the solenoid. Use heavy wire (like 10 ga). This will show not only when the alternator is charging but also the amount of discharge (negative side of gauge)when the alternator is broke or the engine is not running. It will also tell you if the alternator is not keeping up with the electrical load.

 

Oops, you're right, what was I thinking????

Bob
'66 7 Litre, top loader, 3.25 Traction-lock, Sidewinder Intake, SCJ Exhaust
'88 F150 LWB 4x2, XLT Lariat, 302, 5 speed, 3.08
'99 Ranger, 4x2, 3.0, 5 speed, 3.73 posi