91 fj newbie needs engine

[Pskhaat]

...or indicate such bad rod as earlier stated :-O

 

[Tools R Us]

Well I pulled the valve cover yesterday and no broke valves spring etc,just a little bit sluggy.It looks like it's not oiling to well.You can turn it over and run it for a second and not much oil seems to come out.

That's normal, the push rod motors don't pump much oil to the valve cover.

I put some decarbon spray in the plug hole last night and when I came out this mourning I noticed the piston was at the top.I stuck a long screwdriver in and pushed the piston down by hand!! I guess I do have a broke rod.You would think something like that would make a LOT of racket.

It looks like you can pull the pan pretty easy.I guess I'll look at the damage and go from there.

Has anyone ever pulled a piston from the bottom?

Sounds like a broken piston, they are known to break at the oil ring leaving the skirt attached to the rod, the head of the piston is not moving so no compression.

 

[Dweezil]

I can't get my oil pan off! I fell like a tool.I have tried all the methods I know (except for driving a screwdriver and prying it) and it won't budge.What's the trick?I don't want to destroy my pan.

What usually makes the piston break?Does this mean the rest are subject to break as well?I know a rebuild would be best.But since it has only 155,000 on it, would it be safe to patch it with a new piston and rings.

 

[Tools R Us]

Hold a piece of wood (4x4) low on the side of the pan put your stock jack between the frame rail and the wood and apply force, give it a little time to work, then tap on the wood with a BFH, usually pops them free. Better done with the oil drained or it can get messy!

 

[Tools R Us]

What usually makes the piston break?Does this mean the rest are subject to break as well?I know a rebuild would be best.But since it has only 155,000 on it, would it be safe to patch it with a new piston and rings.

It's rare but they do fatigue crack, the others may not be affected. The only way to tell is pull them all out and clean them up. if you want to reuse the same parts mark everything so they can go back in the same place. If you don't want to rebuild, do what we call a ring and bearing job. Source a used piston, Steve from Man-A-Fre is doing a motor and may have one? Get a cheap set of rings, no moly or trick stuff, a set of rod bearings, pan, head, valve cover and exhaust gaskets. Pull the pan, head and pistons, hone the cylinders so the new rings will break-in and reassemble.

 

[Steve-O]

It's rare but they do fatigue crack, the others may not be affected. The only way to tell is pull them all out and clean them up. if you want to reuse the same parts mark everything so they can go back in the same place. If you don't want to rebuild, do what we call a ring and bearing job. Source a used piston, Steve from Man-A-Fre is doing a motor and may have one? Get a cheap set of rings, no moly or trick stuff, a set of rod bearings, pan, head, valve cover and exhaust gaskets. Pull the pan, head and pistons, hone the cylinders so the new rings will break-in and reassemble.

Pretty much what I did to my motor. So far everything is turning out great. You also have to clean the ring grooves for the new rings. If you dont get the head and the block decked, definately stone them and use copper-coat to re-seal it.

I do have a used piston if you want it, but personally I would try to get a matched set.

 

[Steve-O]

I can't get my oil pan off! I fell like a tool.I have tried all the methods I know (except for driving a screwdriver and prying it) and it won't budge.What's the trick?I don't want to destroy my pan.

My pan was stuck too, I got frustrated and pryed it off, now I have a new pan because I bent it up so bad. I could have straightened it, but it was all banged up from when I threw a rod anyways.

Has anyone ever pulled a piston from the bottom?

You wont be able to pull the piston out from the bottom, unfortunately it wont fit around the crank.