Replace Main Bearings ???
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From: Minnesota
Replace Main Bearings ???
I've had low oil presure and have dropped the pan to replace OIL PUMP and ROD BEARINGS ---- now CAN THE MAIN BEARINGS AND SEALS BE REPLACED from underneath by just loosening the crank or must engine be pulled ??? Thanks John
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From: Fraziers Bottom, WV
If you replace the oil pump and rods with the engine in the truck, I see no reason you could not do the mains. You may need to unbolt the motor mounts and lift the engine some!
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From: Broken Arrow, OK
You can usually change the mains just by removing the caps one at a time and pushing the block side bearing around with something that won't scratch the crank. You won't be able to check clearances like this.
Whether or not you can change the seals depends on what year the truck is. If it has a one piece rear main either the engine or the trans must be pulled. If it is two piece you can usually do it by just pulling the cap. The front seal is pressed into the timing cover and will require removing the balancer.
Whether or not you can change the seals depends on what year the truck is. If it has a one piece rear main either the engine or the trans must be pulled. If it is two piece you can usually do it by just pulling the cap. The front seal is pressed into the timing cover and will require removing the balancer.
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From: Minnesota
Year of Truck 1991
Thanks---Thats what I was hoping on the bearings --- but its a 1991 and isn't that the one piece REAR SEAL ?? which would entail pulling xmsn/clutch to replace... John
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From: Minnesota
Just Wanted To Say After Replacing Rod, Main Bearings, Oil Pump, Rusted Out Oil Pan------we Now Have Great Oil Pressure.
A Point Of Interest When I Used A Gauge To Check Pressure Before Bearings The Needle On The Gauge Would Vibrate At A Very Fast Rate When Rpms Were Raised-----i Assume This Was As The Crank Rotated And Bearing Clearances Flexed We'd Lose Pressure Giving The Vibration On The Undamped Pressure Gauge.... Thanks To All Who Commented.... I Didn't Have Two Much Trouble Dropping The Pan And Installing Bearings-----another Succesful Repair .... John
A Point Of Interest When I Used A Gauge To Check Pressure Before Bearings The Needle On The Gauge Would Vibrate At A Very Fast Rate When Rpms Were Raised-----i Assume This Was As The Crank Rotated And Bearing Clearances Flexed We'd Lose Pressure Giving The Vibration On The Undamped Pressure Gauge.... Thanks To All Who Commented.... I Didn't Have Two Much Trouble Dropping The Pan And Installing Bearings-----another Succesful Repair .... John
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What engine do you have? 300 - 6 or 302 V8? I have a spun rod bearing and want to replace all bearings from underneath if I can. Thanks.
kw
kw
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Posting Guru
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From: Adams TN
i am also thinking of doing the main and rod bearings and put an oil pump in my 300
was it to difficult?
how long did it take?
could it be done in a week end?
any tips to make it go easier?
was it to difficult?
how long did it take?
could it be done in a week end?
any tips to make it go easier?
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From: Minnesota
My 300 ci 4.9L 1991 F150 Bearing Job 7/04
I suppose it could be done in a few hours but I'm not to fast any more.
Many of the others comments I read were quite on -- but ......
I loosened the MOTOR MOUNTS , and TRANSMISSION MOUNTS, LOOSENED FAN SHROUD, and then jacked it up on the front pulley -- pushing rather hard on the WINDSHIELD WIPERMOTOR,, BLOCKING BETWEEN MOTOR MOUNTS,, which gave me adequate room to pull the PAN.
I was able to put in Bearings & the Two Part Oil seal without dropping the Crank.
Besure to check your oil pan for RUST THRU --- mine looked fairly good but in sand blasting the Rust I could see light thru it so I had to replace the PAN.
John in MN.
I suppose it could be done in a few hours but I'm not to fast any more.
Many of the others comments I read were quite on -- but ......
I loosened the MOTOR MOUNTS , and TRANSMISSION MOUNTS, LOOSENED FAN SHROUD, and then jacked it up on the front pulley -- pushing rather hard on the WINDSHIELD WIPERMOTOR,, BLOCKING BETWEEN MOTOR MOUNTS,, which gave me adequate room to pull the PAN.
I was able to put in Bearings & the Two Part Oil seal without dropping the Crank.
Besure to check your oil pan for RUST THRU --- mine looked fairly good but in sand blasting the Rust I could see light thru it so I had to replace the PAN.
John in MN.
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From: Adams TN
thats cool
i wouldn't of thought of that. thanks for the tip.
i would have been using a screwdriver if you hadn't told me
how long did it take you?
i am like you i don't like to rush when it is something that important. i like to take my time think it out and get it done right the first time around
though being 16 i can get fustrated and impatient
i wouldn't of thought of that. thanks for the tip.
i would have been using a screwdriver if you hadn't told me
how long did it take you?
i am like you i don't like to rush when it is something that important. i like to take my time think it out and get it done right the first time around
though being 16 i can get fustrated and impatient
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