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Old 09-13-2013, 07:06 AM   #1
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Broken piston skirt, any words of wisdom on replacing

I had a knock for the past few days and decided to tear into it it last night to see what I could find. Well...pieces of the #2 piston skirt was not what i was hoping for.

I am going to have to replace it, anyone else done this themselves and remember a step or two they wish they knew before hand?

Right now I only have the pan dropped and rod disconnected, going to start on the head today/this weekend.

Any advice? I think my number one hurdle right now is getting the specs on the piston, rings and rod bearings. Pricing them last night I noticed they are all sized. Is that only if you do some machine work on the crank and cylinder walls, otherwise go with standard sized?

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Old 09-13-2013, 07:28 AM   #2
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How many miles are on your engine? If its up there..... and if it was mine, I would roll in new crank and rod bearings. Unless the rod or main journals are really scratched up. if not go back with the size that's in there now. Also since you had them loose, for me, it would be the time to re ring the pistons if the cylinder walls mic out ok. I would want to pull the other pistons to check for more skirt issues.

Just mu .02

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Old 09-13-2013, 08:37 AM   #3
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What's up with broken piston skirts on the 4.0? If replaced, what is the likelihood of it reoccurring?
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Old 09-13-2013, 08:42 AM   #4
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Metal in my oil pan means time to tear down and rebuild everything. It's way to easy to miss something small, then do the repairs only to have to start over again.
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Old 09-13-2013, 09:01 AM   #5
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My initial plan of action is to pull all the pistons and Inspect, replace all the rod bearings, new gaskets and head bolts. Hone the one cylinder and new piston, rings. Unless something else presents itself once I get the head off.

It has 187,000+ miles (PO didn't do a speedo correct when lifted and tires). It's a 4cyl so I am not going to sink a lot into it for now, rather save the money for a bigger engine swap, sooner than later it seems now.
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Old 09-13-2013, 09:09 AM   #6
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187k and a broke piston. Pay me now or pay me later.
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Old 09-13-2013, 09:18 AM   #7
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If it was me I would do a rebuild. Magnaflux heads and block and Machine work, replace all goodies down to oil pump then enjoy.
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Old 09-13-2013, 09:57 AM   #8
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So... if the PO didn't do a speedo gear swap that 187k could easily be 200K, I agree, since you are into it. Do the over haul.
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Old 09-13-2013, 10:38 AM   #9
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I did the speedo as soon as I realized it hadn't been done, at about 165,000. I'm not sure where in its life it got the bigger tires, but I'd bet 200000 easy.

I personally can't see spending to much on a 4 cylinder though
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Old 09-14-2013, 11:12 PM   #10
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Well the head came of with no issues. Not a scratch on the cylinder, looks like it will be a simple fix.
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Old 09-14-2013, 11:54 PM   #11
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I remember way back when 289 fords with high milage-quite common to have several piston skirts cracked ( light knocking) maybe winding them small blocks up a bit too much?. However, unless the cylinder(s) is/are scored just replace the pistons (all). close inspection of the others will probably reveal others cracked, usually on each side close to the wrist pin boss and either side of the skirt. Unless you don't want the 4 cyl engine. I would just overhaul it with new pistons, rings, inserts, freeze plugs, cam brgs in block, cam, lifters,(maybe push rods-check) valve job, new seals, oil sending unit, gskt OH set, oil and water pump IF you can do it yourself. Otherwise if you gotta pay someone else it may be as economical to drop in a low milage engine/trans from salvage yard.
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Old 09-15-2013, 12:22 AM   #12
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Unfortunately, parts wise, that's roughly 700+ in parts alone. Even doing it yourself, if you go that route you should still have the head decked, and the wrist pins need to be pressed in still.

After all that, it's still a 150ci 4 banger. Your getting into the realm of lower milage v6 and v8 swaps.

I think my thread got misconstrued. I was asking about tips removing the head to get to the piston. I learned a good one...example :Take the a/c compressor and alt. bracket off first, and you have a place to put your foot when going after the intake and exhaust manifolds. We all know you have to be part contortionist, part spider monkey to get to some stuff.

I'd love to throw a ton of parts at it, but sometimes a fix is just a fix.

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