So my favorite big project, Deere 644e with a 6466T engine, well it keeps slobbering on the rear axle from the the crankcase breather, I looked on both sides of the engine for a Detroit diesel sticker but nope, it says Deere. Its a steady fog of blowby, and an oil drip now and again too. Not sure what the standard is. Companies like Reliance seem to sell engine overhaul kits, the clock reads 29000 + hours and I have no service history on how many hours are on the engine itself. It starts and runs decent, a tiny bit of oil from the turbo. I'm leaning toward a rebuild on the engine, new pistons, rings, sleeves etc. Seems like the correct path is to pull the pan and check the crank, get some good measurements with a micrometer and then order up a rebuild kit. Kits seem to run under 2k for the most part then I'd also like to overhaul the rear main seal and have the cyl head checked. Guessing it might be 5k overall, does it sound like I'm in the ballpark?
Hard for me to say because the head work could make a big difference in the overall cost. Don't forget to measure the camshaft lobes. New bearings for it are mandatory IMHO.
Blowby.? You need these boys ............
I would replace that turbo as well since a turbo can also be a source of blowby. Just for your info the Deere spec for blowby measured with a water manometer is 2" of water at full rpm full load.
you never said, but it depends also on how much work you do yourself and what kind of shape the block is in( liner counterbores) etc. also, maybe your rods will need new top bushings and the lower ends checked. the main question is how many hours does it need to last? that will determine how much its worth spending. if its actually 29000hrs on that engine there may be a lot of worn-out parts. so, you have to determine- full actual rebuild or patch job
I had a6466 head done a few years ago new seats guides and valves it was about 600 if I remember right.
Cam bearings cheap insurance?
too much go go gas? they seem to know what they want to get done!!
got a couple questions, is that plug the breather and measure blowby or 2 inches of water up top someplace like say the oil fill cap? water is easy to work with. I've resealed a couple turbos for the ford navistar engines, its really just a under $50 kit for all the rings and seals vs a rebuilt turbo, I'd think if the compressor and turbine wheels are in good shape, can do the rest on the bench in an hour.
Absolutely. It just doesn't make sense to me to put new bearings on a crankshaft and new piston pins (or con rod bushings) and then lose some oil pressure because of worn camshaft bearings. If you do remove the cam bearings be sure to mark the position and direction (front or rear) as soon as each one comes out. It is critical that the oil holes in them line up with the oil supply holes in the block.
On something like this, provided the coin was available and justified in terms of what the engine is going to be expected to do after the intervention, my motto would be "do it once, do it right". You're going in twirling wrenches you might as well do all the little incidentals (like cam bearings and cam gear train bearings) as well while you're in there.
Yeah, have had auto experience with that, where someone put bearings in wrong and caused all sorts of fun damage! This machine gets run maybe 100 hours a year and still gets an annual oil change but my goal is keeping its value up so a full kit is within reason as then we'll have a known quantity for not only the driveline but for the engine as well. Axles, seals and center pins and a slew of other things were done a few years back.
Leave the breather open and place the water monometer over the dipstick tube. Here is a picture of my homemade one that hangs on the back of my tool box (sorry it is upside down). You fill the manometer with dyed water (I use food coloring dye) to the "0" and when the engine is hot, full throttle full load you add the the numbers above and below the "0" to get your inches of water.
Keen, so dipstick toob! I'll give it a test Sunday, nothing that fancy though as its a one shot test!
A friend just knocked apart a 8.1L Deere with way to much blowby on 14,000 hours. Started good at 25F, good power. 5 of 6 top rings were broken.
Similarities with the Doosan in the YouTube video then..........pretty much every top ring fell apart on that one also.
Man..... I wish more thought like that!! I am SO tired of cleaning up messes!
I always say, "Any job, big or small, do it right or not at all." Unfortunately although I always consider it, I don't always practice what I preach. The machine is not always worth it.
Sure you can do it right on something new and shiny but if the whole machine is old and decrepit then it is nice to know the ways to do it quick and dirty to just get by until it throws a rod and gets sent to the junk pile. Like if you have an engine with a bad lifter, scratch in a lobe but cleans up OK and the rest of the lobe looks all right, got blowby and a bunch of hours, and the rest of the machine is rough but still works, just clean up the lobe and throw a new lifter on and let it run the rest of its life before something non-economic happens to kill it.
A millennium ago I had an old JD450 dozer with a hard start complaint when cold and even though the compression test was all within spec every top ring was busted. Since then I only use compression tests to find hard failures like broken valves or holes in pistons. I use a leak down tester most of the time if I suspect cylinder issues.
Agreed with doing the job right within the Venn diagram of available parts, finances and skill/size of hammer assortment
I have an OTC leakdown tester but have never used it is it suitable for Diesel engine use? Nobody at work has ever talked about doing a leak down or compression test. I don’t have a ton of engine work experience yet either (we have a specialized guy who does most of the work)
So, I gave the manamana test today! step 1, don't pull the dipstick at idle, you get a nice spray of oil vapor, mark tube install on dipstick filled with super orange washer fluid as all the water around is frozen. At idle, 1.5 inches displacement, at full throttle someplace between 2.25 and 2.5, there was a lot of wind from the fan at full bore.
Well, if you could find a 12/14mm adapter to your fuel injector. or get some dummy injectors.
Yes. I made an adapter for my leak down tester that fits the compression testing adapter. Too much.
I'll pull the air filter and sprinkle some stop leak in there while its running
I've used an extended rubber tip blowgun for a "quick and dirty" test to see where the leak is. Just keep your fingers out of the belts.
To clarify, the full RPM, FULL LOAD blowby test, that would be dependent on a clean blow by tube, and full load would be readable from the seat in the cab trying to climb a hill in a too high gear. correct or no?
Usually a converter stall will be enough to load the engine to rated rpm (rated rpm could be anywhere from 1800 - 2200 rpm, each family of machines have a different spec). Sometimes a combined stall (converter and hydraulic) is needed to reach rated rpm. Sometimes the blowby test fails just at fast idle without a load. But for Deere it should not exceed 2 inches.
This was just sitting still while having someone mash the throttle, my tube is only 2.5 feet long, I'd have to run very fast to keep up if it was in gear.
The spec on most Japanese engines is one inch of water at full load. I did some Cummins engines a few years back where they put a restrictor in the breather tube and then check pressure. If the engine was in a warranty period, Cummins would just keep giving you higher pressures for the spec. When they got to sixteen inches, I didn't care what the factory specs were. There was something wrong with the engine. Cat doesn't use the crankcase pressure test. Their breathers were so big you would never get a reading. They use a wind meter plumbed into the breather. So much air has to go through the meter to get a reading. I used to do the manometer reading anyway on the smaller engines. I found out that the smaller engines had more and more pressure as they got newer. I'm guessing they had to plug the breathers into the turbos to keep from blowing out all the gaskets and seals on the engine. On the politically correct engines now days, the manometer is of no use so it just stays home on the tool box.
seeing the Deere with 2.5 inches at the dipstick with an open 1 inch plus breather line, seems to be doing a lot of breathing!
In the CTM1 6466 service manual it specs maximum blowby out crankcase breather tube @ 494 cu ft/hr, wonder how one would test that? (Edit) I didn't see JohnCs post above... I've got the manual in PDF if you need it.
Take the turbo drain loose and run into a jug and see if the blowby goes into the jug.
The turbo drain line goes directly into the crankcase. Of course it's going to have blowby. What comes out of the turbo itself is going to be a lot of oil.
Crankcase pressure or just breathing hard, I have seen some engines that put out very little crankcase vapor but plug the breather tube with your thumb and in a few seconds it's pushing oil out the dipstick tube and that includes Cat, Cummins and Series 60. But hot even with high hours I expect to see a slight/steady vapor fog out the breather. It's when you see it huffing a vapor out the breather or oil fill that is concerning. And with 29,000 hours I would expect it to breath hard. The 3406 Cat is one that on the fuel island it's pretty common to see vapor floating out below engine after it just came off the highway. The 12.7 L Series 60 in the tow truck I drive breathes hard but runs fine and has a long way to go. Until I see it huffing it will just run the way it is. In most cases a percentage blowby test doesn't really mean squat, like I said breathing hard doesn't mean it's dead-Huffing She's got a problem, and that ain't spray paint in a sack either.
When I'm looking at older machines with a breather hose and see any vapor coming out, I have to measure the crankcase pressure, if for no other reason than to provide a fact that can be checked again in the future. The decision on whether or not to tear into the motor is dependent on a lot of factors that are the concern of the owners. In my mind if it starts and doesn't use so much oil that it shows a stream on the ground, its good enough, unless there is some outside authority to force me to shut it down.
Agreed.
Boost like anything else will take the path of least resistance . When a turbo pumps boost into the crank case it looks like blow by. The turbo drain should only have oil draining out never under pressure. Hence the jug. But I concur with the posters before that with those kind of hours I would just go on and build it. Can it be in framed? Of course turbo and injectors would need to be addressed as well.
Well if the manometer reads pressure and you could guesstimate the cross section. Of the breather, assume low friction loss and put in the numbers.
Nope. Not unless you want to remove the bottom guards and the fuel tank. I would remove the engine. The engine can be removed in a snap on 644E's.
Yeah, the service tech who did the pre-purchase inspection noted its likely been rebuilt at least once. With the oil pan being right on top of the axle, it seems easier to just pull the engine out and work it that way. Book says 1600 pounds ? Kubota can pick 2000.
I say lets rebuild this engine right here!
Can you guys live stream the rebuild on here? Its frozen and boring around here. lol
Well, I suppose!! I posted a time lapse of splitting the 644e in order to have the center pins rebored! I might be able to video the engine yank and overhaul! I gotta manage my budget, might get the piston and sleeve kit, then order bearings once I get access to the crank.
Question for you deere mechanics, are the cylinder head valve depths as critical as it was years back? I remember rebuilding heads mainly for six cylinder engines and the seat and valve faces were hard as hell. I would cut the seats and face the valves using stellite stones, then depth mic each valve and move them around and re-mic each valve in the seats. Mark each valve to go back in that seat then deck the head to bring everything in range, which usually was no more than .008 off the deck.
Yep. Valve depth, head thickness and both piston and liner protrusion are all critical measurements that must be checked on a rebuild.
I realize the P&L issue on any diesel but the deere heads were critical on valve depth unlike some other engines.
Taking notes! All listed in the service manual?
Yes everything is in the service manual CTM1. I would upload it here but it's 30+ MB. Send me a pm with your email.
Try this, I just about broke my phone in half trying to get the link haha! https://drive.google.com/file/d/155RpCxdLUkoQEETD1kh2QoMEDUqlGzVU/view
I have the big paper set, parts, couple service books, wiring diagram and something else too,
Good deal, you confused me by the question of if the head specs were in the service manual.. I would have assumed you'd have read through it already.
Oh of course not! I mean certainly that book has all the raw data, and a lot of it! but the experience of someone that's been ears deep is the appendix the books are missing. Generally with a 12pc hammer set and some vice grips and the book I can get by. But like on the hydraulic piston seals, there is no mention of using a ring cut from a 2 liter bottle and a worm hose clamp to precompress that soft gray sealing ring versus letting it stand for 8 hours or such. The Deere is at the shooting club shop and most of the times I'll get there with the intent to so some research when someone comes over to borrow a tool, complain about something, ask for help moving something big etc. I love how detailed the wiring diagram is though.
We just finished our 544E engine. 13000 hrs never been into, head had so many cracks, not visible on deck, that it wasnt feasible to fix. It had been putting coolant in the crankcase for 3-4 years, I would go out and drain it off every couple days, when it got to a cupfull a day I told the boss its time. LOL 2 spun mains, 1 spun rod. Had the block reconned, got a good standard crank, rods rebuilt. Exchange head. Its in the machine and should have it running next week, Moral is, inspect everything closely , replace rod and head bolts. ALSO, check the trans input driveshaft, if it is siezed on the slip, while the engine is out pull the convertor cover and replace the bearing, when stuck it will pull on the convertor and eat the bearing and pull the pump drive shaft out of the convertor splines. Then you have to get a long die grinder and de-burr the splines in the convertor hub, while sucking the oil out. Very tedious, trust me on this,.LOL
Boy that sounds like a pickle!! Luckily for the moment our coolant is oil free and vice versa! As to the trans, we pulled the shaft out a while ago, wasn't too siezed but was a little stiff with some old grease. We changed the u-joint on the trans side and cleaned up the slip yoke right purrdy and gave it some extra lube. I suppose if the engine comes out its a good time to check that bearing!
Well today was the day, removed the engine from the Deere and got it in the shop. The oil mixed with coolant is black and sludgy! Found a few issues, 1 the cam gear wasn't fully seated on the cam and the bolt and gear were lightly scuffing the cover, will have to investigate why it wasn't installed all the way. 2 there are numbers on the connecting rods but they don't match anything except rod-cap numbers, I guessing it was part of the rebuild process. Main caps seem to be in the right order Now I have the manual set or so I thought, is there one that covers engine overhaul? I have injector pump removal and other stuff but nothing that says engine overhaul details. Is that a separate manual all by itself? Anyway will be extracting the liners, one came out with the piston, might have hooked on the rod or something but that's okay. Searching to find some shops in the area that handle diesel engine work, really only found one good one so far.
A 6466 repair manual P/N is CTM1.
I think I'm in error! Looking at the engine tag and it calls itself a 6076T not a 6466T is that a different manual? CTM6 possibly, hard to get solid data on it. Are the differences between the two huge?
I got lucky, the splines and the weird rubber coupler on the flywheel were both in great condition
Engine serial number below 499999 uses CTM6. Above serial number 500000 uses CTM42
Thanks, looks like the model/serial is RG6076T100571 Will see about digging up the ctm6, Thanks!!
So Deere sells the manual with a 2 week printing lead time for around $100, some joker on ebay is selling one or trying to for $245, bite me. I found a PDF online for free from a training school in Mexico, I'm learning so that counts. I'll run to Staples and save my toner for later, and I have a hard time with double sided printing. Punch it for a 3 ring binder and be done with it. So checked the oil pump and it's well within spec with maybe 0.0015 of play out of an allowed 0.006, no chipped teeth or scuffing so it'll get re used. The oil tubes in the pan are fretted, likely from vibration, the flywheel and crank damper had piles of concrete-ish dust packed in there, a good shovel full between the two. The Son of Boston Fuel injection is going over the injection pump, Diesel's fuel injection repair in Bow NH. Hillside Machine shop in Malden is polishing the crank and rebuilding the head as well as fitting the bushings to the rods and honing them. Hillside is getting the rebuild kit for about the same as internet list price, under 2k for the kit and will get the price for the machine shop work. Diesels estimates $1500 to go all through the injection pump, could be +/- depending on condition. Even though this machine gets maybe 100 hours a year at the most, the engine will be brandy new ish! The engine I'm taking down is not far from a soup sandwich, it was likely supplied by a rebuilder so i have found a few issues. 1) cam gear not fully seated on cam, allowing the cam to walk the gear into the front cover and skewing the timing retarded by 1/4 tooth or so. 2) injection pump timing not set correctly, likely due to #1 3) speck of dirt beneath a main cap bearing shell showing as a worn spot on the shell itself. 4) hammer dent on the front cover mating surface. 5) injector lines not clamped. 6) missing 3rd sheave on crank pulley (local mechanic error perhaps, belts all askew) 7) dent on oil pump mating surface, possibly allowing a leak, lapped flat on surface plate. 8) strings of silicone sealer in the coolant system. Engine block blasted with EZ-off and let soak for a couple hours, all galley plugs and bearings removed., hot water pressure washer and hot soap used to remove all grit, grime, paint and everything from the block inside and out. Hot block blow dried and coated with wd-40. Next step is running a solvent brush through all the galleys and getting the block ready for crankshaft test fitting once all the goodies are in from the machine shop. I even like to mop the floors before starting an engine assembly as a reminder to be clean about everything and not miss a step.
Busted top rings was a common condition on the 8.1 Deere engines. Often the top land was broken, too. I was told they moved the top ring up on the piston to help reduce emissions. They changed strategies later on ?? maybe because the top land became wider and stronger. We had several low hour piston/ring failures at the Ag dealership I worked at.
Guessing that this has 12k plus hours, tons of blowby, cylinder top was wiped out rings were good and pistons looked new. Getting a full rebuild.
Replace the fretted oil pump tubes. They are very difficult to get to seal once removed.
If i recall, deere kits used to come with high temp o-rings(brown or maybe orange?) for the tubes. Some kits may use the common black ones and they eventually will likely get hard and not seal the tubes very well. You may have to get the o-rings from deere to get the correct ones
Engine has been in service a while. Made a custom cylinder liner driver / installer as well as a cam bearing tool. Having a lathe is a blast. Deere parts online was able to get all new oil tubes and o-rings, and a few calls to some dealers had a set of cam bearings coming, a dealer in ohio had 10 on hand. I'm glad Deere has their inventory locate services. Runs well for certain now, can't see anything coming from the blowby tube. Now we're replacing hydraulic lines, that gets expensive fast!!