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Bobcat 853

they make specific hot rolled bucket cutting edge, it is something like 1055 steel so weldability is gonna be shit too

maybe just go with A36 or AR plate if you're looking to weld it.
 
Bobcat had the best deals a one time for weld on replacement cutting edges
 
Small update, no pics.

Drained coolant and changed the water pump and thermostat and fan belt idler pulley (preventative maintenance).

in take pickup tubes break a LOT on these things... buy a handful.
Ha! Winner.

I got to following the line from the fuel pump to see where it goes into the tank, I couldn't tell last time. I followed it today and found they cut a slit in the fuel fill tube and shoved the fuel pump hose into the tank there. Fucking farmers! Guess they got tired of those pickup tubes breaking. I have a replacement.

The engine oil leaking at the front of the engine is either the drain hose, or the front main seal. I poked around a bit today trying to understand the goofy foam shit on the big cover on the front of the engine. Seemed like a farmer fix with some kind of shit gasket. Turns out there's a steel cover over the engine with a big chunk of foam underneath (like soundproofing). I think I'm going to change the front main seal since I'm there anyway.

Considering just pulling the engine for no other reason than to clean both the engine and the engine bay. If I do, I'll also change the rear main seal.

Looks like the rear main seal is more than twice as large diameter than the front. Would this be because it's got a huge bearing to withstand the side load the drive belt puts on it?

I had to pull the muffler to access the t-stat and found the exhaust leaks. The flex tube was loose at the muffler, and I also think it's broken (flex tube with stainless braid). I'm about 99% sure you're not supposed to be able to stretch the tube. I can stretch the stainless braid, then when I push it back together it's super easy, then a hard stop when the assumed broken pieces touch.

Found the mitered intake elbow to be a bit loose on the intake manifold, so I guess I'll be making a new gasket for that. I've got plain cereal box type gasket and also the high temp stuff with metal in it. I think the cardboard stuff is good enough unless you guys say otherwise.
 
Have fun with the pickup tube. If you stand on your head with the cab up you can kinda see it. I was able to pop mine out with a prybar and attach the hose to the new one and push it bac in with the prybar. I you are pulling the engine that would be the time to do it. Do the fuel sending unit too while you have access.
 
Considering just pulling the engine for no other reason than to clean both the engine and the engine bay. If I do, I'll also change the rear main seal.

I almost suggest doing it since you're this far in.

I had a leak i couldn't find on my 773.. replaced everything I thought might be suspect that I could reach w/o yanking engine. I pointed that out when I sold it - what I had done, what I thought was the issue, what I knew/didn't know, etc.

new owner told me it started leaking bad a few days after buying... turns out one of the pump bolts broke and was pouring fluid out.
 
From this exploded view you can see hose #19 which goes from tank to fuel pump. It gets the in tank pickup screen (part #10).

Why is there a second in tank pickup tube (the one connected to hose #27).

If it was tank vent it wouldn't have a pickup tube...



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if the fuel gauge don't work, the sending unit's float fell off
mine did and I neglected to change it when I had the damn engine out, now it'll never get swapped out...
 
I always worked around the engine and onetime I ended up pulling it out. It was so easy I regret never doing it before.
 
Well, I'd like to retract my "fuckin farmers" comment.:laughing:
Those fuel connections to tank are just not accessible without pulling the engine.

I got the harmonic balancer (crank pulley?)y off and can see the front main seal, so not gonna pull the engine just for the fuel connection, at least not until I get this pig back together and run it for a couple hundred hours. Pulling it would also have made fixing the exhaust leak easier, but I gots a plan.

Interesting the front main seal runs on the harmonic balancer instead of directly on the crankshaft. There's not really anything sealing the crank to the balancer other than a close fit, and probably centrifugal force keeping the oil slung off the crank.
 
Interesting the front main seal runs on the harmonic balancer instead of directly on the crankshaft. There's not really anything sealing the crank to the balancer other than a close fit, and probably centrifugal force keeping the oil slung off the crank.
and a slug of RTV behind the crank bolt's washer
 
bucket lip steel. and just fyi they call that the mold bar.

use t1 or a514. i build and repair allot of buckets and thats what they all get. i'm told its very similar to ar400, but been anealed longer making it resist cracking much better
 
Depending on the use and all, but I just recently rebuilt a Bobcat brand grapple bucket and picked up the heavy duty flavor (3/4") of the titan 1055 cutting edges. Won't last forever, but its also my grapple so its not seeing a ton of gravel work but it needed something because the old one was worn plum the fawk out.

 
Finally had time to do the main seal.

Tapped the new one in with the old one. I just made sure the surface was wiped clean and dry. Didn't use any lube, not sure if I was supposed to.
I did grease the harmonic balancer though.

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Came up with this to hold the crank for torqing. Didn't work as the outer pulley slipped on the rubber between the metal parts.

Added vise grips and torqued to 140 pounds.

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Sub'd, I just got ahold of an 853 too. Sitting fir years but after fresh fuel and batt it fired right up. Couple hoses replaced, messing with the BICS sensors and it was operational.

Kinda sketchy to drive tho as I need to figure out what is causing the sticks to not be synced. Hoping it's just adjustments and not internal stuffs.

You have to mess with that on yours at all?

And asmentioned before the struts on can should have a locking lever on right side as sitting in seat, left if you're looking at it from front
 
Sub'd, I just got ahold of an 853 too. Sitting fir years but after fresh fuel and batt it fired right up. Couple hoses replaced, messing with the BICS sensors and it was operational.

Kinda sketchy to drive tho as I need to figure out what is causing the sticks to not be synced. Hoping it's just adjustments and not internal stuffs.

You have to mess with that on yours at all?

And asmentioned before the struts on can should have a locking lever on right side as sitting in seat, left if you're looking at it from front
I've got the service manual on PDF.

PM me your e-mail and I'll send it to you.

There's a procedure to sync the sticks. You need to tilt the cab up and make (or buy) a wiring harness to start the motor. Machine is supposed to be on blocks obviously when this is happening.
 
Moderately frustrating day.

Started out rigging this up to use a spool gun sized spool in my 255, so I could weld my stainless elbow to a stainless flex tube.

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Then found out what I thought was stainless flex was really only galvanized (and probably not rated for exhaust temps?) Walker lists galvanized as good up to 300C, aluminized up to something hotter and stainless up to hotter yet. The amazon listing I bought from says stainless steel and galvanized... :homer:

I blame the booger weldz on the fact that my Draeger charcoal filter respirator doesn't fit under my welding hood, and I was too chicken to weld stainless to galvanized without it. Ended up welding while holding the mask. Oh well, I doubt this cobbled shit will last anyway.

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Then found out that nobody in town sells 1 3/4 inch exhaust tubing, so I had to buy a 2 inch piece, section it and weld back together to get the correct diameter, then miter it to clear the thermostat.

Also cut and rotated the muffler to make for a better angle.

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Finished the day by redoing the fuel system (new see through filter, new water separator, new hoses/fuel injection clamps).

Pulled the engine oil filter and have one coming in tomorrow.

Added 14 liters to the coolant system, changed the intake hoses and put the air filter housing back in and the cover for the belts.

Hope to run it tomorrow.
 
So, got it running.

Engine oil dipstick is funny, it connects to the crankcase below the oil level, so there is always oil in the tube. Turns out the oil leak is oil coming out the tube. It gets worse when revved up. If I pull out the dipstick I get a solid 1/4 inch stream of oil coming out. This is at 1/4 throttle. I opened the oil fill plug when running and the oil stops coming out (this relives the pressure obviously).

So, I'm not sure if there is too much pressure somehow, or if the vent is plugged. I took the hose off the valve cover vent and the hose isn't plugged. I'm not sure if there's some kind of valve (PCV?) built into the valve cover. There is something there that can be taken off. I'll try that tomorrow.

Is there another vent for the crankcase? Seems to me since there's gears for timing, the pressure in the crank should be the same pressure that's in the valve cover.

Exhaust doesn't smoke at all.

Thoughts? Advice?
 
This thing looks like what is on the valve cover.

Listed as a crank vent, so I'm guessing that's what's under there. Stuck? Or can't pass enough volume because engine problem like broken rings or hole in piston?

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Pulled the vent thing on the valve cover. No holes in it, and it looks fine. Got a little spring to keep it closed.

Seems it's designed to let air into the motor, and check valve to prevent air exiting the motor.

There is a small hole about 1/16 inch that connects the valve cover to atmosphere, bypassing the checkvalve. So, obviously the engine is making more pressure than the 1/16 hole can vent.

I pulled the intake manifold and fuel lines and pulled all four glow plugs.

I have a snap-on laproscopic camera to look at the tops of the pistons and cylinder walls. The cam fit down the threaded part of the glow plugs, but the hole tapered down at the bottom, and the cam wouldn't fit through.

How do glow plugs seal? Threads don't look tapered, and I don't see a sealing surface.
Edit: Nevermind, I see the tapered part just before it necks down. That gets squished into the block to seal.

Now to get my hands on a leakdown tester.
 
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Moderately frustrating day.

Started out rigging this up to use a spool gun sized spool in my 255, so I could weld my stainless elbow to a stainless flex tube.

P3072042.JPG


Then found out what I thought was stainless flex was really only galvanized (and probably not rated for exhaust temps?) Walker lists galvanized as good up to 300C, aluminized up to something hotter and stainless up to hotter yet. The amazon listing I bought from says stainless steel and galvanized... :homer:

I blame the booger weldz on the fact that my Draeger charcoal filter respirator doesn't fit under my welding hood, and I was too chicken to weld stainless to galvanized without it. Ended up welding while holding the mask. Oh well, I doubt this cobbled shit will last anyway.
My miller the plastic spindle for the spool rides on a 5/8" steel shaft. Pull off the plastic and you can slip a 1-2# spool on. Is the Lincoln that much different?
 
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