New owner of Z482 engine.

[Apogee]

Hi Diesel,

Hope the layoff doesn't come true.

If you do decide to go through the engine, do yourself a favor and buy the proper size flex hone. You will get a much better end result.

http://www.brushresearch.com/product-line.php?line=1

Good luck,

Steve

 

[dieseldude]

Hi Steve,

Thanks for the tip on the flex hone. It looks to be almost fool proof to use, no adjustments to make compared to others. I think de-glazing and new rings will be the way I would go. The last time I had the head off, there were a few small vertical scratches,nothing deep but enough to notice. Could this be from a stuck or broken ring? Something tells me its just not going to be as simple as a seal. Along with that, probably a new head gasket and re-lap the valves while I have it torn down.


Is it possible to do the honing without removing the crank? I wouldn't want to disturb something that's working right. I have heard stories of honing with it removed and with it in place. Seems to be personal preference. My only concern with the crank in place is grit getting into the oil passages and on the journals. before I forget is there a preferred grit for deglazing?

Thanks

Dave

 

[dieseldude]

A quick update for anyone interested.

Myself and a co-worker were discussing how my project engine is coming along, and we both had an idea. Valve stem seals. When I pulled the valve cover, sure enough 3 of the 4 stem seals are missing. All that can be seen is what appears to be where they attach.

So the next parts to get stem seals, rings, head gasket.

Sooner or later it will run correctly again.

 

[dieseldude]

It look's like I may have to bench this project for a while, at least until the work situation improves. Pulled the head off this morning, then moved on to pulling out the pistons, not good news. One piston has 2 big pieces missing just above the oil ring, the other has a seized oil ring and the wrist pin is sloppy. So it looks like to finish this up I'll have to get a head gasket, valve stem seals, 2 sets of rings, 2 pistons, little end connecting rod bushings, and de-glaze the cylinder walls. At least the big end bearings and crank pins look and feel alright. Starting to get the impression I'll have a practically new engine when done.

So in short, Dissapointed but not yet defeated.

 

[aquaforce]

So in short, Dissapointed but not yet defeated.

That is the spirit, hang in there and it will be worth it in the end.

When I was digging into the problems of my engine I really hated that it got major but I'm on the other side of a full build back and I love it. Once you get it done you will love it too. Don't cut any corners because it is not worth it.
Good luck with the work and post some pics if you can.

 

[dieseldude]

As requested, some photos of the teardown, cylinder walls, and pistons.

 

[aquaforce]

Wow that was fast on the pics.

The paint on the block and the blue on the rod really show that front cylinder got very hot. The piston looks scorched too. Wow that thing was so hot I would be very guarded about the head. Definately check it for cracks.

 

[dieseldude]

yea, the burnt paint concerns me as well. The pistons aren't quite as bad as they look, they cleaned up so-so enough to see it wasn't completely burnt but did have hot spots. As far as the head goes, I spent a good amount of time wire brushing tearing down and cleaning, so far all looks ok. It checks out for flatness less than .002" across the six way of checking so it may still useable. The block check out as well. I'm not sure this is the original head. It's not painted gray like the rest of the engine, its more of a off red orange but not like any kubota orange I have ever seen. I'll get some picture of it up tomorrow after getting things pulled out for the up coming hurricane Sandy. Looks like we may get a direct hit.

any idea what would have cause it to get that hot since it was suppose to have a high temp and low oil pressure shutdown system?

 

[dieseldude]

something a little different but still engine related today. Since I have some time to tinker while figuring out the next batch of parts to get, I though to myself there has to be a better way to compress the valve springs then by finger. Now the obvious anwser is a spring compressor but where's the fun in that. Heres what I came up with. An attachment for a drill press. It allows to compress the spring without it slipping, allows access to both keepers, and the best part made from recycled material.

 

[dieseldude]

a few pics of the head after a good cleaning and inspecting. Just for reference. The cylinder on the right is #2 or the rear it had the stuck oil ring. Also a shot of the valve seats after a quick lapping. Note the orange color, I dont think this is the original head.

 

[dieseldude]

quick update:

Started to gather required tools for the upcoming rebuild. I picked up a ring expander, still trying to learn to used it (yes it's my first time redoing rings). Looks like I may have to modify the tool a bit to accept rings that thin and narrow. At least I still have the old rings and pistons to practice on.

When the work situation improves, next to be purchased is a "flex-hone" 240 grit 67mm hone, pistons, rings, wrist pins, small end con rod bushings, big end bearings (current ones look fine no scratches or wear spots, but have to disconnect the rods anyway so may as well do them while I'm there). By the time I'm done everything except valves, valve guides, water pump, inj. pump, fuel pipes and head will have been replaced or rebuilt. Sounds almost like a new engine.

 

[skeets]

I think it would have been cheaper to buy a crate motor ,,, not as much fun but cheaper,,lol

 

[dieseldude]

skeets

If I didn't such a good deal on it to begin with, it probably would have been cheaper to buy new even though I didn't intend to buy one at all, right place right time kind of deal, lol.

But being old school way of doing things, I'd rather be hands on and maybe pick up a few new tips in the process. In fact your reply reminded me of something I haven't seen in a while, "the makers bill of rights" and the "self repair manifesto". Somewhere in there there's a line that reads "if you can't fix it, you don't own it". Even though those articles are geared toward electronic equipment, a lot of it is still relevant to everything. If you have the chance, give em a read, kinda interesting.

 

[dieseldude]

let the rebuilding begin.

Just ordered the hone to deglaze the cylinders, When that gets here, I'll put some before, during, and after pictures up.

 

[dieseldude]

Just did my first honing of a cylinder and it turned out fairly well or so I believe. Thank you to who it was that pointed me to the flex hone, my apologies I'm horrible at remembering names.

As promised a few pics of the deglasing / honing.

Happy Thanksgiving.

 

[dieseldude]

It's been a while since I last posted. Life has a funny way of putting project on the far back burners and keeping them there.

For a quick progress update, ordered the hopefully last of the parts for the rebuild. In this next batch should be 2 new piston and ring sets, new upper and lower rod bearings / bushings, new wrist pins, and a head gasket and the ever important Kubota blue paint. With any luck these will be in by the middle of January.

It looks like the re assembly should start soon.

 

[dieseldude]

everything is here, time to star re-assembly in the morning. the new parts fit together much closer. Rings are at the upper end of the specs but within limits. Rod bushings nice tight press fit into the rods. Wrist pins installed after heating pistons in oil to expand. So first thing in the morning, everything that moves getting a light coat of oil then on to the wrench spinning.

 

[dieseldude]

Update:

I think this might be the last update. After putting the engine back together, adding fresh oil, fresh fuel, bleeding the lines, I attempted to start. No go on the first try. Tried again, some white smoke and a few coughs, still no go. third time it caught and kept running. After burning off the assembly oil, exhaust cleared and idled smooth, good oil pressure(it pegged my gauge at 60psi). It does like to have glow at 50 degrees. Haven't run it long yet due to no cooling hooked up and also have to fix a little glitch with the starter, it doesn't grab the ring gear every time.

I'd like to thank everybody for their input and suggestion in doing this rebuild / refreshing. For anyone interested, I may post in the fabrication section what I actually build using this engine.

Thanks again.

 

[Z482EngineGuide]

For all those looking for a bit more information on this engine, I found a site that seems to have some information on it.

They also have a section where you can ask questions about the engine, as well. I've gotten a few questions answered there already.

Check it out: Z482EngineGuide.com

 

[North Idaho Wolfman]

Forum Poacher!!!!