440 rod bearings
- Thread starter Andrew
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Andrew
Well-Known Member
The motor is on a stand and I have the rods out. One of the cam bearings is beat up. Apparently it was either insalled wrong or turned 1/8 turn so the ol hole is not lined up. There is obvious damage in the form of actual holes in the bearing. Some metal (probly from this bearing) must have circulated thru the motor. There are some shallow vertical scratches on the cyllinder walls and the piston skirts also have some mild vertical scuffs. A few cam bearings look crappy. The rod bearings from what I see took the least damage, but since they are out, if I can, I figure I might as well change them. Typical budget constraints, I don't want to pay someone to do it if I don't have to; but I've never done it before.
Is it do-able with-out presses or am I asking for trouble? Someone told me without resizing the rods, I will probably spin a bearing.
Any opinions?
Is it do-able with-out presses or am I asking for trouble? Someone told me without resizing the rods, I will probably spin a bearing.
Any opinions?
daredevil
Well-Known Member
Bearings come right out when the caps are unbolted. are you meaning the pins? You could plastigage it to make sure they are clearanced properly.
Meep-Meep
дворянин
Looks like you have quite a stew going on there. If the cam bearing spun then the cam bearing installation was not done right or the cam was bent. Either way the cam might have not been fitted properly. Or the installer had one too many!! A blocked oil passage at the cam bearing will not restrict oil flow to the rods. Which cam journal had the issue? The 4th one back from the front is important as it sends oil to the valve train.
As it says above, perhaps you are thinking of piston pins (small end)? Those will need to be pressed out if you have to remove them. Removing them can ruin the piston pin as one end is pressed through the rod. If the piston does not float nicely on the rod then you may have issues there. Sometimes it's hard to get oil in the pin area if there's too little clearance.
Minor scuffing on the piston skirts is not the end of the world. Measure them carefully and decide if you still have usable clearance after a light hone. Light scuffs on the cyl walls should clean up with only .002" material removed and some small witness marks are OK. I have honed and re-ringed many engines with good results - some by hand using a rigid hone.
If you spun a rod bearing (big end) and the rod is chewed up then resizing at least that rod will be required. You can change rod bearings, or inserts, without resizing the rods so long as you don't knock the bolts out of the rod and the rods are in pretty good shape to begin with. If the rod bolts have lots of tightening cycles on them (been apart a bunch of times) then it's a good idea to at least put new OE quality bolts in. New bolts will require that you resize the rods.
The crank may have taken a hit as well so you should at least have that polished.
As it says above, perhaps you are thinking of piston pins (small end)? Those will need to be pressed out if you have to remove them. Removing them can ruin the piston pin as one end is pressed through the rod. If the piston does not float nicely on the rod then you may have issues there. Sometimes it's hard to get oil in the pin area if there's too little clearance.
Minor scuffing on the piston skirts is not the end of the world. Measure them carefully and decide if you still have usable clearance after a light hone. Light scuffs on the cyl walls should clean up with only .002" material removed and some small witness marks are OK. I have honed and re-ringed many engines with good results - some by hand using a rigid hone.
If you spun a rod bearing (big end) and the rod is chewed up then resizing at least that rod will be required. You can change rod bearings, or inserts, without resizing the rods so long as you don't knock the bolts out of the rod and the rods are in pretty good shape to begin with. If the rod bolts have lots of tightening cycles on them (been apart a bunch of times) then it's a good idea to at least put new OE quality bolts in. New bolts will require that you resize the rods.
The crank may have taken a hit as well so you should at least have that polished.
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It isn't uncommon for part of the oil hole(s) in the cam bearing to obscure the hole in the block. Simple fix simply requires a long drill bit and some "touch"
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