1984 Case 780 A336BDT

[Tinkerer]

No need to post a photo of the tach-drive plug Jason. I know what it looks like. All 301 and 336 tach-drives are the same. Your center photo clearly shows a a tach-drive in place with like new looking teeth.
I myself found no need for the neutral safety switch,but for the sake of your safety it would be a good idea to connect it again if it is still usable. Looks like you lucked out ans got a really nice engine from the looks of the crankshaft photos. If you still have the oil pan off it may be a good idea to check the torque on the rods and crankshaft journals.

 

[Jasonswett]

Hello everyone,
Sorry for the delay in updates. I do have the engine in the backhoe and started piecing things together, slowly.

Tinkerer, I did check the torque while the engine was opened up. Thank you for mentioning that.

Unfortunately, on Christmas day I sprained my ankle pretty good and pulled a muscle in my leg. So that put a halt on everything. But good news, I am back on my feet and slowly losing the limp that I gained.

Next up for the backhoe is everything from the fan forward (fan, radiator, shroud, oil cooler, etc..) I am still confused with the tachometer. The tach drive is there. But when I remove the plug, there seems to be a rod or shaft that comes out of it. How does this work with the cable? The cable has a shaft coming out of it that looks like it should slide into the drive. Any insight to this would be great.
I did reuse the switches and sending units for now until I can find replacements. They are easy to change with the engine in place. While I am finding those and getting all the correct wiring I need, I know the machine should still run and function.
I am having trouble finding one hydraulic fitting for the boom. No one locally or within a reasonable distance seems to have it. And trying to search for it online hasn't been easy at all.

So all in all, between my ankle and weather, things have been slow going. But fingers are crossed that it's up and running in the next week.

Hope everyone had good holidays and happy new year!

 

[Tinkerer]

The core cable that is inside the flexible housing should have a (male) square end on it. it should slip into to the drive assembly that is in the block. You could remove the cable from the tachometer and take look at it. Both ends of the flex (core) cable should look the same. Did the square part of it stay in the old drive when you removed it ? Any CNH dealer can get a new (flexible) core for the tach cable. You have to cut it to the correct length for your application. They are net very expensive. Glad to hear you are feeling better and r back at reassembling the engine.

 

[Jasonswett]

Well, good news and bad news.

The engine is in, all hooked up, and ran for about 5 minutes. I shut it down when I saw a fuel leak in the line off the tank. So I replaced the fuel line and re-bled the fuel system.

I went to start it back up, and now I have what looks like water coming out of the exhaust. And not moisture kinda water. Like water coming out of the kitchen sink kind of water. When I try to start it now, there's no smoke. It cranks and the water just flows out. A few minutes after cranking, it'll eventually stop.

At first I thought it was fuel because it didn't look like antifreeze. So I pulled all the injectors and changed them out. It made no difference. But now the water has a slight green tint to it. I didn't use any water when I filled the engine. I only used 50/50 antifreeze.

So I'm thinking it's probably a head gasket. Praying it's nothing worse. But preparing myself for another nightmare.

Any tips, tricks, or ideas on these headgaskets? If I pull the injectors again and crank the engine over, it may tell me which cylinder it is. But either way, I would replace both gaskets. Are the heads known to crack at all?

The plan is to pull it apart tomorrow and order what I need and hopefully get it back together next week. Weather depending of course and as long as I don't find anything else wrong.

This is like a smack in the face and has really got me down. It's just one thing after another. Thank you all again for any insight and info. I really do appreciate it.

 

[thepumpguysc]

That sux.. to be sure of the fluid, just taste it.. it wont kill ya..
DONT spin it over anymore!!!! you'll be dam lucky if you didn't bend a valve/push rod already..

 

[Tinkerer]

Take off the exhaust manifold and then add water to the radiator, then crank it over. Hopefully only one of the heads need to come off.

 

[Jasonswett]

Well the news isn't good. I have a cracked cylinder liner/sleeve. Other than that, everything looks good for the most part. Including the head gaskets.

So now I am in the process of deciding how far I wanna go to fix it. I have basically 3 options which are (in order by cost, low-high):

1) remove a sleeve from my old block, hone it, and replace o-rings and gaskets. Done with the engine in the backhoe. Roughly $170 plus fluids and filters.

2) same as #1, except order a new sleeve kit. Also done in the backhoe. Roughly $250 plus fluids and filters.

3) pull the engine back out, order a complete overhaul kit, have the block cleaned and checked along with the heads. About $1600 plus fluids and filters.

So my next question is, what would you do in my situation?

I was looking up parts and trying to figure out which ones fit my engine. There are two different sleeves listed. The difference seems to be in the 'sleeve fire diameter'. Can anyone explain where on the sleeve this measurement is taken? From what I can tell by measuring different areas with my caliper, it's at the top on the outside edge of the sleeve, but not the most outer edge. If that makes sense.

I'll put up some pictures of the damage later when I'm on the computer.

Hope everyone is having a great weekend. Cheers!

 

[Jasonswett]

One last quick question, any idea what would have caused this to happen? Could it have been anything that I did and could prevent from happening again?

Thank you!

 

[Tinkerer]

We can't tell you which way to go with your repair Jason. I can tell you what I would do though. That would be remove the engine from the tractor and do a complete overhaul. Camshaft bearings included. I am just really fussy and would want a like new engine when I was done. If you do take a sleeve out of your old engine be sure to use the same piston that was in it. The turbo charged engine uses different sleeves than the naturally aspirated diesel. The photo shows where to measure the fire ring diameter. In regards to what happened to your cracked sleeve ---- water from an open exhaust pipe would be my guess. The condition of the other sleeves -- hmmmmmm.

 

[Jasonswett]

Well I'm still up in the air with what direction I'm going. I did see a rebuilt short block on ebay for $6200 with a 1 year warranty which could be another route to take.


In the mean time, here are a couple pictures of the crack.

 

[Plongson]

Be prepared for that $6200 to increase...possibly significantly. My $5900 long block turned into $9700 by the time I replaced hoses, belts, engine mounts, injectors etc.

I plan on keeping the tractor and cut no corners, fixing, repairing and inspecting along with installing the new engine...that's not saying something won't flair up someday...but let me tell you, there ain't nothing like having the confidence on a cold winter morning to go out and fire up your tractor and put it to work...and NOT having to fix something first.

My vote is for a new engine.

 

[Tinkerer]

I dunno Jason, you said earlier you were looking at a used engine for $2995.00. Add that $6200.00 for short block and that puts you over $9000.00. Figure maybe 3 or 4 hundred more to get the heads redone. It's not looking good on paper to me. Put a complete overhaul kit in the engine with the cracked sleeve and save yourself about $4000.00. I don't know what your budget is but, be prepared to have issues with other things on the entire machine.
Just as an example; if the splines on the hydraulic pump input shaft are badly worn it will take about $400.00 to replace it, and the female part of it that bolts to the crankshaft damper. It appears from reading your posts that you are capable of doing all the labor yourself. Hopefully
I just looked at the rebuilt engine that is on Ebay. U have $225.00 shipping to add to the $6200.00. Farmland tractor is a good place to deal with. I have purchased from them directly myself.

 

[Jasonswett]

Hello Everyone!
Sorry for being away so long.
I ended up rebuilding the engine from top to bottom. It runs great now. I still have a few seals/hoses to replace on the hydraulics but I am focusing on the running/moving parts first. I have noticed a few leaks on the radiator but haven't had any luck finding a replacement yet. I'd like to replace the brakes but that's around $800+ just for the shoes so that is on hold until I get the radiator squared away. I've also been looking around for a rebuild kit for the transmission and have had no luck. Other than that, I try to tinker with smaller things on it when I have time. A light here, and a hose fitting there.

For the little amount I've had the time to use it, it's a strong machine. It does seem to get stuck quite a bit when I have a load in the front. So I'm wondering if filling the read tires would help with that..?

Another small issue is the rear boom lock. There's no parts left for it on the machine so I bought some steel to fabricate a new one. The backhoe swings and moves a lot so that's moved up a bit higher on the priority list.

If anyone has a dead machine sitting around with parts available, I'm interested. It's a lot of small stuff that I'm looking for.

Hope everyone is doing well!

Jason

 

[Tinkerer]

Thanks for the update Jason, I was wondering how your project is going. In regards to your radiator; take it to a professional and have them quote a price on a recore job or whatever it needs. If the brake shoes are salvageable take them to a heavy truck repair shop and have them relined. The drums would have to be really badly worn before I would replace them. Everything in your air brake system including replacement brake chambers can be purchased at NAPA or on Ebay.
The boom cylinder should hold the boom up for decent amount of time. If not put a new seal kit in it.

 

[chestypuller]

i was wondering if you had a extra connecting rod? im trying to fix a 336bdt case in my 780ck too

 

[Tinkerer]

i was wondering if you had a extra connecting rod? im trying to fix a 336bdt case in my 780ck too

Don't limit your search to 336 connecting rods. 301 cubic inch engines used the same rod.
Call Dale Wiess at http://e-backhoeparts.com/ . He may be able to help you.(765)-378-3396

 

[chestypuller]

Thank you tinkerer, ill check him out also.

Im still dreading pulling this big 4 cylinder, i got everything unbolted since i couldnt get the oil pan out due to front axle parts in way to completely remove pan and do in frame. do you guys think its necessary to support the transmission from underneeth with cribbing when pulling? id hate to mess anything extra up.

 

[chestypuller]

i pic of my rod for fun

 

[Tinkerer]

No need to block up the transmission. It has very strong mounting brackets. They are notorious for the bolts coming loose. What happened to the engine to cause that kind of damage to the connecting rod ?
Crankshaft damaged ?

 

[chestypuller]

wow i took a long time to respond, still havent pulled it, picked up a generator with a cummins 4b in it with a sae 3 pattern, hoping to get something going to be able to move it around. tell i can get the engine fixed, the guy i bought it from was driving it low on oil down a mountain or up one here in alaska i think he said down and it boke it.