BACKGROUND
My brother's 1990 Accord EX sedan 5MT with F22a4 has 368K miles (JHM VIN prefix, made in Japan) on it currently and with full maintenance performed, including a timing belt job. It never had the cylinder head removed as of 216K miles, when our family purchased it. Engine performance is surprising for the 368K miles on the engine and it currently gets 27.2 MPG. However, it burns 1 qt of motor oil every 400 miles!! My brother needs this car to last another 2 years and I'm afraid he will run motor low on oil and seize it.
DIAGNOSIS
I had my wife start the car with the engine cold and I watched the tailpipe. No initial puff of smoke, but once engine was running it smoked constantly. Very obvious smell of burning oil while the engine was running.
Out of curiosity, I did a compression test and got 180-190 psi across. I assumed the carbon build up from the oil created a artificial engine seal. I removed cylinder head, sent it to the machine shop to get it inspected and reconditioned. The shop found one broken valve guide and one bent exhaust valve on cylinder # 3. This surprised me considering the good running condition of the engine. The shop confirmed the valve guide seals were not the cause for the engine oil consumption, so it was what I originally thought....piston rings.
PLAN OF ATTACK
Recondition the cylinder head, already done.
Piston rings need to be replaced. Considering the block is still in vehicle, I plan to remove the stock piston/rod assemblies through the oil pan, ball-hone the cylinder walls, install new piston rings on the stock pistons and reassemble.
I know the professional and proper procedure for the engine rebuild, since I've built my own performance F22ax motor (white project). Nonetheless, my brother has a limited budget and I need to improve the situation for this engine to last another 2 years.
Ultimately, after all the work completed, this engine will be compared to its intial measureables to gauge improvement:
Current:
MPG: 27.2
Oil Consumption Rate: 1 qt/400 miles
PROGRESS
Cylinder head is removed, refreshed and awaiting install. New OEM gaskets, parts and ball-hone tool all ordered. I receive everything by end of this week. I decided on a 320 grit ball-hone (Flex hone brand), bought the 3.5" nylon cylinder brush and honing oil. I am aware the Helms service manual states 400 grit for honing with stones.
Also, I'm taking advantage of this time to do some preventative maintenance. For example, my bro had the heater core outlet hose burst on him not long ago, I repaired. Therefore, I am replacing the rest of coolant hoses. All IM coolant hoses are replaced and remaining heater hoses. Negative battery cable replaced, it was significantly frayed.
Intake manifold EGR blocked off to prevent future clogged EGR passages and driveability issues. I cleaned the oil build up inside the TB, plenum and runners. Also cleaned the IM flange gasket surface, IM is ready for install. Block deck surface is also cleaned for new headgasket install.
Next on this list:
- Clean piston/rod assy, clean cylinder walls & ball-hone
- Clean cylinder walls very well, lightly coat with motor oil
- Install protection on rod studs to protect crankshaft
- Lightly motor oil coat inside of ring compressor sleeve
- Install piston ring compressor tool on pistons
- Clean rod bearings, apply Torco MPZ engine assy lube
- Install piston/rod assy into cylinders
- Torque rod stud nuts to spec
- Install new oil pick-up gasket & oil pick-up, torque to spec
- Install new oil pan gasket & oil pan, torque to spec
- Reinstall all other components to complete engine assy
- Using Torco MPZ engine assy lube as necessary for camshaft/valvetrain.
- Adjust valve lash, bleed coolant system, set base idle & ignition timing
- Run cheap motor oil & filter for about 30 miles, drain motor oil
- Perform final motor oil change & filter
- Test original measureables against new to gauge improvement (take 3.5 work days for 400 mile accumulation)
- Also, perform leakdown test after 400 mile accumulation to gauge engine health
PRICING TOTAL: $500
- reconditioned stock cylinder head (cleaning, valve job, valve seals, resurface) $200-225
- IM gasket $10
- EXH gasket $20
- headgasket $50
- piston rings $90
- oil pan gasket $20
- oil pickup gasket $2
- honing tooling $80 (320 grit ball-hone, honing oil & nylon cylinder brush)
OPTIONAL (not included in total):
- valve cover gasket kit $25
- rocker arm lower O-rings (qty: 4) $10
- connecting rod bearings (qty: 4 sets) $72
RESULTS
Old:
MPG: 27.2
Oil Consumption Rate: 1 qt per 400 miles!!
New:
MPG: 29.8 (15-20 deg F weather)
Winter Oil Consumption Rate: None in 400 miles.
Warm Weather MPG: 30+
Spring Oil Consumption Rate: Short of 1/2 quart @ 4,000 miles, March 2010.
My brother's 1990 Accord EX sedan 5MT with F22a4 has 368K miles (JHM VIN prefix, made in Japan) on it currently and with full maintenance performed, including a timing belt job. It never had the cylinder head removed as of 216K miles, when our family purchased it. Engine performance is surprising for the 368K miles on the engine and it currently gets 27.2 MPG. However, it burns 1 qt of motor oil every 400 miles!! My brother needs this car to last another 2 years and I'm afraid he will run motor low on oil and seize it.
DIAGNOSIS
I had my wife start the car with the engine cold and I watched the tailpipe. No initial puff of smoke, but once engine was running it smoked constantly. Very obvious smell of burning oil while the engine was running.
Out of curiosity, I did a compression test and got 180-190 psi across. I assumed the carbon build up from the oil created a artificial engine seal. I removed cylinder head, sent it to the machine shop to get it inspected and reconditioned. The shop found one broken valve guide and one bent exhaust valve on cylinder # 3. This surprised me considering the good running condition of the engine. The shop confirmed the valve guide seals were not the cause for the engine oil consumption, so it was what I originally thought....piston rings.
PLAN OF ATTACK
Recondition the cylinder head, already done.
Piston rings need to be replaced. Considering the block is still in vehicle, I plan to remove the stock piston/rod assemblies through the oil pan, ball-hone the cylinder walls, install new piston rings on the stock pistons and reassemble.
I know the professional and proper procedure for the engine rebuild, since I've built my own performance F22ax motor (white project). Nonetheless, my brother has a limited budget and I need to improve the situation for this engine to last another 2 years.
Ultimately, after all the work completed, this engine will be compared to its intial measureables to gauge improvement:
Current:
MPG: 27.2
Oil Consumption Rate: 1 qt/400 miles
PROGRESS
Cylinder head is removed, refreshed and awaiting install. New OEM gaskets, parts and ball-hone tool all ordered. I receive everything by end of this week. I decided on a 320 grit ball-hone (Flex hone brand), bought the 3.5" nylon cylinder brush and honing oil. I am aware the Helms service manual states 400 grit for honing with stones.
Also, I'm taking advantage of this time to do some preventative maintenance. For example, my bro had the heater core outlet hose burst on him not long ago, I repaired. Therefore, I am replacing the rest of coolant hoses. All IM coolant hoses are replaced and remaining heater hoses. Negative battery cable replaced, it was significantly frayed.
Intake manifold EGR blocked off to prevent future clogged EGR passages and driveability issues. I cleaned the oil build up inside the TB, plenum and runners. Also cleaned the IM flange gasket surface, IM is ready for install. Block deck surface is also cleaned for new headgasket install.
Next on this list:
- Clean piston/rod assy, clean cylinder walls & ball-hone
- Clean cylinder walls very well, lightly coat with motor oil
- Install protection on rod studs to protect crankshaft
- Lightly motor oil coat inside of ring compressor sleeve
- Install piston ring compressor tool on pistons
- Clean rod bearings, apply Torco MPZ engine assy lube
- Install piston/rod assy into cylinders
- Torque rod stud nuts to spec
- Install new oil pick-up gasket & oil pick-up, torque to spec
- Install new oil pan gasket & oil pan, torque to spec
- Reinstall all other components to complete engine assy
- Using Torco MPZ engine assy lube as necessary for camshaft/valvetrain.
- Adjust valve lash, bleed coolant system, set base idle & ignition timing
- Run cheap motor oil & filter for about 30 miles, drain motor oil
- Perform final motor oil change & filter
- Test original measureables against new to gauge improvement (take 3.5 work days for 400 mile accumulation)
- Also, perform leakdown test after 400 mile accumulation to gauge engine health
PRICING TOTAL: $500
- reconditioned stock cylinder head (cleaning, valve job, valve seals, resurface) $200-225
- IM gasket $10
- EXH gasket $20
- headgasket $50
- piston rings $90
- oil pan gasket $20
- oil pickup gasket $2
- honing tooling $80 (320 grit ball-hone, honing oil & nylon cylinder brush)
OPTIONAL (not included in total):
- valve cover gasket kit $25
- rocker arm lower O-rings (qty: 4) $10
- connecting rod bearings (qty: 4 sets) $72
RESULTS
Old:
MPG: 27.2
Oil Consumption Rate: 1 qt per 400 miles!!
New:
MPG: 29.8 (15-20 deg F weather)
Winter Oil Consumption Rate: None in 400 miles.
Warm Weather MPG: 30+
Spring Oil Consumption Rate: Short of 1/2 quart @ 4,000 miles, March 2010.
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