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Discussion Starter #1
Well after searching for diesel to swap in and the required work needed. I don't have the space to do the engine swap. I'm going to stay with the underpowered 302. I need to do a compression test to even see if this motor is worth the effort. The engine started dying at random and I smell oil and coolant when I drive. I'm assuming no it's leaking. We'll I hope anyway.

Question is. Anything else to check on the motor? Is adding power to the 302 a waste of time? Just a daily and some trailing

Addicted to Junk
85 Bronco, 309ci I6 w/4bbl, np435, 4" lift, 37" Irok NDs, 4.56 w/ Detroit Locker and tru trac
12,375 Posts
The 302 is a great engine, just not the factory truck version. You can easily modify it to hit 300hp. Heads, cam, higher compression, and a good exhaust should get you there, or close.

Super Moderator
25,024 Posts
Yo Jay,
Re, "...engine started dying at random..." Does it re-start quickly or after a cool-down period?
Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19
Post Code(s) here according to:
A helper can assist you by counting the codes. Some use their smart phones to record them.
Or ask local mom and dad parts stores if they will test it for you. The majority of parts chain stores tests just OBDII vehicles now.
Or purchase a coder reader such as Equus 3145 Innova OBD I Code Reader for Ford EEC IV Engines at Walmart & most parts stores.
Could have a vacuum leak(s). Or;
Air filter, is it relatively clean?
Air inlet atop radiator support to filter box and to throttle body; look for obstruction; damaged tubing, openings in tubing, loose fit at throttle body or if equipped, at MAF sensor.
Fuel quality; Oxidized fuel often turns darker over time and may even smell sour. You can check stored gasoline by pouring some into a clear glass container and comparing it side-by-side with known fresh gasoline. If your old sample looks noticeably darker than the fresh gas, you have strong evidence the gas has gone bad.
Electrical connectors; inspect for corrosion, etc at coil, firewall, ICM, distributor, PCM, etc. especially those with broken locking tabs.

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Some relatively ez-to-do tests:
Check PCV valve system. Make sure system is not plugged.
"A failed PCV valve may also cause noise. Some will produce a whistle or whine and others can produce a low moaning noise. The easiest way to verify the problem is to temporarily block the vacuum source to the PCV valve and see if the noise changes or goes away.
A bad PCV valve can cause oil to blow onto the air filter element. An oily or dirty spot, near the PCV inlet hose is a symptom."

"Visually inspect coolant in radiator coolant recovery reservoir for signs of transmission or engine oil.
If engine oil is evident on vehicles with an engine oil cooler, REMOVE engine oil cooler and INSPECT for damage. REPLACE if damaged.
If engine oil is evident on vehicles without engine oil cooler or if oil cooler checks out OK, REMOVE cylinder head, and INSPECT for leaking head gasket and head or block cracks.
If transmission oil is evident, replace radiator and check condition of transmission oil.
In-tank transmission oil coolers must not be replaced. Instead, for aluminum radiators, replace the complete radiator assembly."

Intake Manifold Vacuum Test[
"NORMAL READING: Needle between -51 and -74 kPa (15 and 22 in-Hg) and holding steady.
NORMAL READING DURING RAPID ACCELERATION AND DECELERATION: When engine is rapidly accelerated (dotted needle), needle will drop to a low (not to zero) reading. When throttle is suddenly released, the needle will snap back up to a higher than normal figure.
NORMAL FOR HIGH LIFT CAM WITH LARGE OVERLAP: Needle will register as low as -51 kPa (15 in-Hg) but will be relatively steady. Some oscillation is normal.
WORN RINGS OR DILUTED OIL: When engine is accelerated (dotted needle), needle drops to 0 kPa (zero in-Hg). Upon deceleration, needle runs slightly above 74 kPa (4 in-Hg).
STICKING VALVE(S): When the needle (dotted) remains steady at a normal vacuum but occasionally flicks (sharp, fast movement) down and back about 13 kPa (4 in-Hg), one or more valves may be sticking.
BURNED OR WARPED VALVES: A regular, evenly spaced, downscale flicking of the needle indicates one or more burned or warped valves. Insufficient hydraulic lash adjuster clearance will also cause this action.
POOR VALVE SEATING: A small but regular downscale flicking can mean one or more valves are not seating.
WORN VALVE GUIDES: When the needle oscillates (swings back and forth) over a 13 kPa (4 in-Hg) range at idle speed, the valve guides (6510) could be worn. As engine speed is increased, the needle will become steady if the guides are responsible.
WEAK VALVE SPRINGS: When the needle oscillation becomes more violent as engine rpm is increased, weak valve springs (6513) are indicated. The reading at idle could be relatively steady.
LATE VALVE TIMING: A steady but low reading could be caused by late valve timing.
IGNITION TIMING RETARDING: Retarded ignition timing will produce a steady but low reading.
INSUFFICIENT SPARK PLUG GAP: When spark plugs (12405) are gapped too close, a regular, small pulsation of the needle can occur.
INTAKE LEAK: A low, steady reading can be caused by an intake manifold or throttle body gasket (TB gasket) (9E936) leak.
BLOWN HEAD GASKET: A regular drop of approximately 33-50 kPa (10-15 in-Hg) can be caused by a blown head gasket (6051) or warped head-to-block mounting surface.
RESTRICTED EXHAUST SYSTEM: When the engine is first started and is idled, the reading may be normal. As the engine rpm is increased, the back-pressure caused by a clogged muffler, kinked tail pipe, etc., will cause the needle to slowly drop to zero. The needle then may slowly rise. Excessive exhaust clogging will cause the needle to drop to a low point even if the engine is only idled.
When vacuum leaks are indicated, search out and correct the condition. Excess air leaking into the system will upset the fuel mixture and cause conditions such as rough idle, missing on acceleration, or burned valves. If the leak exists in an accessory unit, such as the power brake, the unit will not function correctly. ALWAYS SERVICE VACUUM LEAKS."

Coolant Pressure Test: Some parts store will loan you the test kit for a refundable deposit. Also test radiator cap

"Oil Leaks:Fluorescent Oil Additive Method
Add Rotunda Gas Engine Dye 164-R3705 or equivalent to the engine oil. Use 29.6 ml (1 ounce) of fluorescent additive in all engines.
Clean engine with a suitable solvent to remove all traces of oil.
Run engine for 15 minutes.
Stop the engine and inspect all seal, gasket and galley plug areas for leaks using Rotunda Oil Leak Detector 164-R0756 or equivalent. A clear bright yellow or orange area will identify leak. For extremely small leaks, several hours may be required for the leak to appear.
NOTE: For minor gasket leaks tightening the retaining bolts may resolve the problem.
Service all leaks as required."
Examine the following areas for oil leakage.
Valve cover gaskets (6584)
Intake manifold gaskets (9439)
Head gaskets (6051)
Oil bypass filter (6714)
Distributor O-ring
Oil level indicator (dipstick) tube connection
Oil pressure sensor (9278)
Cup plugs and/or pipe plugs at end of oil passages

Under Engine, with Vehicle on Hoist:
Oil pan gasket (6710)
Oil pan front and rear end seals
Crankshaft front seal (6700)
Crankshaft rear oil seal (6701)
Engine damper keyway (damper to damper bolt/washer interface)

Oil Pressure Test:
Engine Oil Pressure Gauge T73L-6600-A or equal.
Disconnect and remove the oil pressure sensor (9278) from the engine.
Connect an Engine Oil Pressure Gauge T73L-6600-A and Transmission Test Adapter D87C-77000-A, or equivalent, to the oil pressure sender screw port.
Run the engine until normal operating temperature is reached.
Run the engine at 3,000 rpm and record the gauge reading.
The oil pressure should be: 392-490 kPa (57-71 psi) at 3,000 rpm.
If the pressure is not within specification, check the following possible sources:
Insufficient oil
Oil leakage
Worn or damaged oil pump
Clogged oil pump screen cover and tube (6622)
Excessive main bearing clearance
Excessive connecting rod bearing clearance."

"[URL=""]Cylinder Leakage Detector

When a cylinder produces a low reading, the use of Rotunda Pressurization Kit 014-00705 or equivalent will be helpful in pinpointing the exact cause.
The leakage detector is inserted in the spark plug hole, the piston is brought up to top dead center on the compression stroke, and compressed air is admitted.
Once the combustion chamber is pressurized, a special gauge will read the percentage of leakage. Leakage exceeding 20 percent is considered excessive.
While the air pressure is retained in the cylinder, listen for the hiss of escaping air. A leak by the intake valve (6507) will be audible in the throttle body (9E926). A leak by the exhaust valve (6505) can be heard at the tail pipe. Leakage past the rings will be audible at the positive crankcase ventilation (PCV) connection. If air is passing through a blown gasket to an adjacent cylinder, the noise will be evident at the spark plug hole of the cylinder into which the air is leaking. Cracks in the cylinder block (6010), or gasket leakage into the cooling system may be detected by a stream of bubbles in the radiator (8005)."

Oil Leak and Valve Guide Seal Test
The cylinder leakage detector can be used to test for engine oil leaks and to check the valve seals for leakage.
Plug all crankcase openings except the one used for connecting the leakage detector.
CAUTION: Use extreme caution when pressurizing crankcase. Applying air pressure above specified pressure risks damage to seals, gaskets and core plugs. Under no circumstances should pressure be allowed to exceed 27 kPa (4 psi).
Connect the detector to a crankcase opening (oil level indicator tube (6754) is convenient) and adjust the air pressure to approximately 20 kPa (3 psi).
Using a solution of liquid soap and water, brush the solution along the gasket sealing surfaces and bearing seals. Look for bubbles or foam.
Remove the spark plugs (12405) and rotate the engine (6007) slowly with a wrench. Check for large amounts of air escaping into the cylinders as each intake and exhaust valve opens.
The spark plugs on the leaking cylinders will probably show deposits of burned oil."

"Valve Train Analysis, Static (Engine Off)
Rocker Arm Cover Removed:
NOTE: Static Valve Train Analysis, with the engine (6007) off, is to be performed before Dynamic Valve Train Analysis which is performed with the engine running.
Check for damaged and/or severely worn parts, correct assembly, and use of correct parts by proceeding with the static engine analysis.
Rocker Arm: Check for loose mounting bolts, studs and nuts. Check for plugged oil feed in the rocker arm (6564) or cylinder head (6049). Push Rods: Check for bent push rods (6565) and restriction in oil passage.
Valve Springs: Check for broken or damaged parts.
Valve Spring Retainer and Valve Spring Retainer Keys: Check for proper seating of valve spring retainer keys (6518) on valve stem and in valve spring retainer.
Positive Rotator and Keys: Check for proper seating in the exhaust valve spring retainer and on valve stem.
Valves and Cylinder Head: Check for signs of improper cylinder head gasket installation such as the shape of the cylinder head and block and the shape of the head gasket (6051) not matching.
Check for signs of cylinder head gasket leakage such as coolant or oil leaking between cylinder block and cylinder head.
Check for plugged oil drainback holes.
Check for worn or damaged valve tips.
Check for missing or damaged intake and exhaust valve seals.
Check valve clearance
Check installed spring height.
Check for missing or worn valve spring seats, if equipped."

"Valve Train Analysis, Dynamic
NOTE: Static valve train analysis, with the engine (6007) off, is to be performed before dynamic valve train analysis, which is performed with the engine running.
Start the engine and, while running at idle, check for proper operation of all parts. Check the following.
Rocker Arm:
Check for plugged oil feed in rocker arm (6564) or cylinder head (6049).
Also inspect for proper overhead valve train lubrication and examine for plugged oil feed in rocker arm.
If a condition of insufficient lubrication is suspected, accelerate the engine to 1100 to 1300 rpm with the transmission in NEUTRAL and the engine at normal operating temperature. Oil should flow from the rocker arm oil holes such that valve tips and rocker arms are well lubricated. If lubrication is insufficient for this condition to occur, check oil passages for blockage.
Push Rods:
Check for bent push rods and restriction in oil passage.
Check for proper rotation of push rod (non-roller tappets).
Positive Rotator and Valve Spring Retainer Keys
Check for proper operation of positive rotator (intake valve only).
Valves and Cylinder Head:
Check for plugged oil drainback holes.
Check for missing or damaged valve stem oil seals or guide-mounted oil seals.
If a condition of insufficient lubrication is suspected, check oil passages for blockage, then accelerate the engine to 1200 rpm with the transmission in NEUTRAL and the engine at normal operating temperature. Oil should spurt from the rocker arm oil holes such that valve tips and rocker arms are well lubricated."
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