1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
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78 F-100 engine problems

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Old 08-07-2014, 03:18 PM
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78 F-100 engine problems

I pulled the motor out to replace the rear main seal and found this



See anything wrong?
 
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Old 08-07-2014, 03:26 PM
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Oh wait, can't see it?


 
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Old 08-07-2014, 03:47 PM
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Someone didn't know how to use a torque wrench.
What are your plans?
Put it back together? Replace the mains? Rebuild?
 
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Old 08-07-2014, 03:52 PM
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Look at the bright side, ya didn't have to ventilate the block to discover something was amiss.
 
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Old 08-07-2014, 04:32 PM
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I'm really torn on what to do, I just bought this truck two months ago and thought it was pretty solid. There was no wraping, knocking or ticking. I new the throw out bearing and rear main was bad but didn't expect this! Options....

1) turn the crank, new mains, maybe rod bearings and hope for the best

2) short block rebuild and hope the heads are ok

3) total rebuild ( the machine shop I want to use is booked till November and I need this truck on the road yesterday)

4) I have a 351w in a 85 f250 4x4 chassis. Disregard the nasty distributor, there's a new DSII dizzy there now



I could put the Windsor in and send the M to the machine shop and then put the M in the 85. There's no rush to get the 85 done, because there's still a lot of body work to do on that.

Any thoughts?
 
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Old 08-07-2014, 08:46 PM
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You should be fine turning the crank and putting new main and rod bearings in. Your compression will not channge, but your oil pressure should improve. With a new gasket kit, you should be good to go. Double check for any broken internal parts. my $.02.
 
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Old 08-12-2014, 04:46 PM
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What about a remanufactured 400?

If I'm not mistaken 77-79 F150/F350's were outfitted with 351m/400 "truck" blocks (D7TE), which were strengthened for the use of a clutch. I also remember seeing somewhere that the heads from 77-79 trucks are stronger than the previous 351m/400 "car" heads.

I did some searching around for remanufactured engines and not many companies have good reviews or any reviews at all! I came across engineguy.com and found some 400's, the only issue is I'm not sure if these are the car application or the truck or what. The site says 72-71 ford 6.6l which is years before Ford made the 351m/400 D7TE "truck blocks" but it also says "block cast D1AE, D4AE, D7TE 8th digit of VIN S" which is the letter in the 400 block f series and broncos...I think.

There is another engine that says 75-82 6.6l 400ci but the pictures totally different, looks like it has overhead cams. The web site doesn't have any casting numbers to cross reference so I called engineguy.com to ask. I spoke with Ashley, she was very courteous and said she would call me back with more information.

I just received a call from Ashley from engine guy and she said that the picture was wrong and that is the f series 400. I asked her to get some more info on casting numbers and compression ratios, etc. She said that she will ask her boss to call me with some specs.

Here's a link
EngineGuy

Anyone use this company before?
 
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Old 08-12-2014, 05:17 PM
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Originally Posted by Piston Honda
Anyone use this company before?
I've never heard of them but that doesn't mean too much, I've always rebuilt my own engines.
If it were my truck I would mic the crank and if the tolerances were okay, I'd put in a set of bearings, a new oil pump and button it back up.
If it was running okay before you pulled the pan, it should be okay after the new bearings
 
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Old 08-12-2014, 07:17 PM
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Originally Posted by mikeo0o0o0
I've never heard of them but that doesn't mean too much, I've always rebuilt my own engines.
If it were my truck I would mic the crank and if the tolerances were okay, I'd put in a set of bearings, a new oil pump and button it back up.
If it was running okay before you pulled the pan, it should be okay after the new bearings
All the bearings are worn on one side and not even. Is this normal or is this from the bolt not being tight?
 
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Old 08-12-2014, 07:35 PM
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Originally Posted by Piston Honda
All the bearings are worn on one side and not even. Is this normal or is this from the bolt not being tight?
Could very well been caused by loose cap. Using a micrometer it's very easy to check the diameter of the journal and to check the journal for "out of round" and "taper".
 
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Old 08-12-2014, 07:42 PM
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Originally Posted by mikeo0o0o0
Could very well been caused by loose cap. Using a micrometer it's very easy to check the diameter of the journal and to check the journal for "out of round" and "taper".
Forgive me for asking "stupid" questions, but what's involved with replacing the bearings? Do I have to remove the heads and pull the pistons out or can I remove the crank with the heads and pistons in?
 
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Old 08-12-2014, 07:57 PM
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Originally Posted by Piston Honda
Forgive me for asking "stupid" questions, but what's involved with replacing the bearings? Do I have to remove the heads and pull the pistons out or can I remove the crank with the heads and pistons in?
Not the easiest way to do it.
You can replace the main bearings without removing the crank. They make a little tool to "walk" the top half of the main bearing out of the block but what I've always used is a nail.
You remove the main cap and replace the lower bearing half like normal. On the top half, you turn the crank so the oil hole in the journal is exposed. Then you insert the special tool (or, in my case, a nail) in the oil hole. You then rotate the crank so the tool is touching the edge of the bearing opposite the side with the lock tab. Then continue to rotate the crank. This will walk the bearing out of the seat. To install the new shell you place the insert on the journal with the locking tab away from the side of the block with the tab. You can work the bearing a little by hand to get it started in. Once you get enough room, you can insert the tool again and rotate the bearing into place, just be sure that the lock tab is seated in the groove.
Probably the hardest one is the thrust bearing but even that isn't too bad.
Really, it takes longer to explain it than to do it.
BTW, my "special" tool is a 16d common nail cut down so its about ¾"-1" long.
 
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Old 08-12-2014, 08:09 PM
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Originally Posted by mikeo0o0o0
Not the easiest way to do it.
You can replace the main bearings without removing the crank. They make a little tool to "walk" the top half of the main bearing out of the block but what I've always used is a nail.
You remove the main cap and replace the lower bearing half like normal. On the top half, you turn the crank so the oil hole in the journal is exposed. Then you insert the special tool (or, in my case, a nail) in the oil hole. You then rotate the crank so the tool is touching the edge of the bearing opposite the side with the lock tab. Then continue to rotate the crank. This will walk the bearing out of the seat. To install the new shell you place the insert on the journal with the locking tab away from the side of the block with the tab. You can work the bearing a little by hand to get it started in. Once you get enough room, you can insert the tool again and rotate the bearing into place, just be sure that the lock tab is seated in the groove.
Probably the hardest one is the thrust bearing but even that isn't too bad.
Really, it takes longer to explain it than to do it.
BTW, my "special" tool is a 16d common nail cut down so its about ¾"-1" long.
What about the bearing size, should it be stock?
 
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Old 08-12-2014, 08:27 PM
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Originally Posted by Piston Honda
All the bearings are worn on one side and not even. Is this normal or is this from the bolt not being tight?
Either the crank is bent or the block needs to be align honed if the bearings are showing uneven wear. Years ago a buddy had a crank in a 400 break in half right trough the middle main. It ran fine up until it broke. Upon disassembly we found the bearings were worn uneven.
If it was me i would go with the windsor and not look back. The windsor is a great engine with alot more power potential then the M engine
 
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Old 08-12-2014, 08:30 PM
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Originally Posted by Piston Honda
What about the bearing size, should it be stock?
Look on the back of one of the bearings. If they're the original Ford bearings they should have a part number and 'may' have "STD" stamped on them.
If they're replacements they should have "STD" or, if the crank has been turned, 010, 020, 030 on them which would be the undersize.
 


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