Hello, I have a problem with the 951c crawler loader motor. Unfortunately enough oil comes out of cylinder 3 in the exhaust. I disassembled the exhaust and o saw that it leaks a little from everyone, but especially from number 3. This was sudden, I started to see cold engine smoke and obviously blue smoke. When the engine warms up it no longer emits smoke and no longer leaks oil. This crawler loader had been standing still for years when I took it, and when I unloaded it it didn't emit any smoke. I parked it to make various repairs and after the tests I noticed this problem. I have noticed that under the valve cover, the spring and valve are moving up and down by half a millimeter. Can this affect and let oil enter the cylinder? Only when cold enters oil, then how it heats are the losses irrelevant? The engine is powerful, it doesn't lose revs, it starts immediately. Every so often when cold cylinder 4 emits bursts, such as cough, injector? I am attaching images. I ran the engine on max for 1 hour. has dirtied everything .. oil comes out of all cylinders. all this oil possible? all piston rings damaged? possible valve guide? I am desperate... Tank you all.
Is it oil or fuel? You could get the injectors checked as they could leak diesel into the cylinders if not working properly. If it clears up when the engine is warm, run the machine and make it work hard. It may clear up. Stuck piston rings and/or valves out of adjustment could be the cause of oil loss.
Hello it's oil. In two hours she consumed 2 liters, lots of blue smoke and the smell of burnt oil. I did the test with the engine at maximum revs. Without working on it, I sped up and let 2 hours go by Oil everywhere at first then passes. At full throttle, no oil leaks. If I go to half throttle, a lot of blue smoke starts again and oil comes out .. The engine is fine except for a few coughs at low revs, it sounds like irregular bursts, then it passes ... valve guides?
Post a Serial Number please. First thing you should eliminate is the turbo. Remove the hose between the turbo and the cylinder head. (This may be easier to say than to actually do) Check for oil in the compressor side of the turbo or inside that hose. When was the last time the engine valve clearances were adjusted.?
No turbo on a 951C, 955L has a turbo. I had my 3204 rebuilt and it went through oil like crazy and had no smoke at all. Seems the rings didn't seat but thankfully it was covered by warranty. Could the crankcase vent be plugged and is the air filter clean? Maybe adjust the valves and work it and see how much oil it goes through. Running at full throttle is not the same as working it and putting a load on the engine. Have seen slobbering/smoking engines clear up after being put to work.
Not to argue about something I have no personal experience but looked on SIS2.0 and see this: One of the reasons a full S/N saves so much time when asking for help!
If you look at the pictures no turbo. So the turbo has already been eliminated. Bob
Check air filter . Most likely rust in the cylinders may have lapped in the rings. The miss may be nozzles going away. Bob
I guess a serial number is in order. I know someone with a 1975 951C and it doesn't have a turbo. Maybe some versions had a turbo but all the brochures I could find don't list a turbo, just 95 H.P. 3304. Maybe a turbo was an option but then why not just get a 955 that is also a bigger machine.
Hello the 951c has no turbo. i had 3 crawler loaders 951, turbo is not expected. The serial is 69h3944. Is it possible to remove the pistons and cylinders without removing the engine?
Hello New symptoms more corrected. The engine starts very well, holds idle and has excellent compression. The problem of smoke and oil leaking from the exhaust occurs when the engine is hot and at medium and high rpm. It is not clear but after about 20 minutes when it is warmed up enough by some bursts, if I accelerate it still works well, but blue smoke and oil comes out. In short, when cold as it seemed, it does not drool and does not smoke. And when it is hot it behaves like this. If they were the rings it would do it a lot more cold (I think). Could it be the valve guides? is it possible and from where does the ignition pump pass oil and from where? What can I check without disassembling the whole crawler loader?
Okay, Guess I need a dope slap for missing that one!
I noticed something else. The ignition pump, the regulator is very hot, it is as hot to the touch as the oil filter. It's normal ? I noticed this right away. Is it possible that oil passes into the pump and is sprayed into the combustion chamber?
the oil is on the bar arrived on add. it was full level. he ate almost all the oil in the tests I just wanted to know if by removing the oil pan I can remove all the pistons and cylinders
As I recall your engine has a flat plate on the bottom over the hard bar and the sump is on the front half so may be difficult to remove back pistons . take a look . Bob
bob do you think it's a problem with rings? I wouldn't want to take everything apart for no reason
Kinda hard to check oil control rings with out looking at them. ,Did you move any hoses or lines while you were starting this motor? Have you checked the air filter? How much blowby do you have? Bob
bob, air filters I even removed them for testing, however it is new. blow by absolutely 0 absolute, none not even a small breath. I checked everything, I don't understand why you eat all this oil. I tried air compression tests, even the fan moves. Is it possible that the valve guides are so shabby?
How does the blow by look coming out of the breather my guess is stuck rings also bad valve guides can cause this. normally if its rings it will burn it but exhaust valve guides will leak oil into manifold and run down block
I think it can be done I know you can on a 955
Did you have any work done to the injection pump? Bob
no, the injection pump did not perform any work. is it normal that it gets very hot? the regulator part of the accelerator
If you pull the exhaust manifold off you probably will see oil running down the guides on to the valve stems. If it has good compression and not much blow by its valve guides that is why you are leaking out raw oil if it was rings the oil would go through the compression cycle and burn up. you have not mentioned about the blow by though how is it
Update Hi guys . I used the crawler loader hard today. Here it is beastly hot, the converter has remained in the green and the coolant in the green. The engine is fine, no revs drop and digs a lot, no smoke. The problem is that the 4 hours ate 10 liters of oil. After 2 hours I turned off to check everything. I turned it back on for another 2 hours maximum and loading and pushing trees. I still used it hard. Tonight I check oil and notice that it is way below the add sign. No leaks from the exhaust, perhaps at full throttle it can burn it and does not have time to come out of the exhaust. I'm embittered . I would not like to open an engine that is running very well. At low revs, blue smoke comes out halfway through the accelerator and gives intermittent coughs, like pops. At full throttle it's great I do not know .... If it were valve guide would it do it at all revs? blow by and completely absent, beyond belief
The injection pump has engine oil running threw it for lubing the pump so it will be oil temperature. Do you have a way to check oil temp? If you do check temp of oil cooler in and out pipes. What kind of oil are you using? It may pay to replace the injection nozzles to cure the miss. Bob
Your Feb 1976 built loader is suffering with knackered pistons, to remove the oil pan is easy but to remove the sump plate you will have to lift the engine around 20 mm to make it easy, this involves removing the drive biscuit bolts on 1 side and jacking the back of the engine up, the front mount is rubber and can take a small movement or you can loosen the front mounts, no Turbo's ever fitted to 951 A, B or C Series, a good thing to also check is the engine oil cooler as it will be at least 20 % blocked, the piston damage could well be caused by pump timing wrong or poor fuel capsules, to use this much oil it would be big chunks of piston damage in the top ring area. tctractors
For the oil I use quality 15w40 Am I wrong? I have always used this oil with success. Could the temperature be too high? If so, why? Clogged engine oil cooler? But doesn't all this affect the consumption of oil, blue oil, and oil leaking from the muffler exhaust? I do not know
You just need to pull he engine down and inframe it there is no magic fix for this
hello ,thank you . I did not understand the question of oil stuck at 20%. By removing the exhaust manifold, oil flows out of all 4 cylinders. Perhaps from the most abundant number 3. All this with a test with the crawler loader stationary. using it, as mentioned, no loss, maybe some, but using it and driving I don't notice, with the heat it dries up and then the symptoms I described in the previous post.
You said it dries up but you said that you are still consuming oil I think its time to tear it down
Yes Before disassembling a good engine I always think about it. I wanted to understand the diagnosis first. At full throttle the oil can burn in the combustion chamber. It is not clear, usually there is a lot of blow by. In this case the engine is powerful and does not lose revs during the effort phase. Usually an engine gone by a thousand other signals and I was not here asking for information from those who have much more experience than me. Would too hot oil risk this problem?
Just run it and check the oil often. If something isn't right your going to find out soon enough. Maybe the rings were stuck a bit and have now freed up..............who knows?
One more longshot pull the valve cover and start the motor and check ends of rocker shaft , if the plugs are missing oil will flood top of head and go down valve stems. I've seen that before but not very often. Over heated oil will go away faster. Dump your fuel filter and see if fuel looks a little dark. Bob
My engine was rebuilt and using a lot of oil. No smoke at all. They said to run it 500 hours to break it in. Still used a lot of oil. Rings didn't seat. Shop even mentioned it had no smoke at well when they drove it across their yard. Thankfully they fixed it under warranty.
You say you have no blowby at all. Not even vapors. I think the blowby tube filter is possibly plugged. You should see at least vapors
slightly, but insignificant. I unscrewed the oil top-up cap at full throttle. It doesn't move at all, zero. What do you tell me ?
well that's not the issue then
Bob has a fairly simple test, pull the valve cover. I believe you said you ran it with the exhaust manifold off and saw oil coming out of all exhaust ports. It sounds to me like the oils going down the valve guides. Shawn
Also, your problem may be caused by worn ring lands on the pistons. If you don't know the history of the engine, i would pull it and rebuild it and then you will know it will last for as long as you need it. Just my opinion
The engine oil cooler will be pegged up with debris in the water side of the cooler, the water pump sends the cooled water from the radiator bottom hose through the engine oil cooler, then into the cylinder block, earlier models had a transmission cooler also, your transmission cooler is air cooled built within the radiator section. tctractors
I disassembled the oil cooler above the filter. it turned out completely clean. The system had a clean blue coolant. There is an oil cooler on the side of the water cooler, all clean. I must say that the system does not heat up and the indicators always remain on the green. My doubt remains. Can enough oil pass through the valve guides to end up in the combustion chamber? Or more simply it is a question of rings. because remaking valid guides is much cheaper and even simpler. This is the question, removing an engine is never rewarding. Removing a cylinder head is easy.
Good info tctractors. Have the valve clearances been checked? I'm defiantly not an engine guy. Will the oil get pulled into cylinder if vales are not seating properly?
If your breather is clogged it can build pressure and force oil past guides and yes valve guides can make oil come out the exhaust especially exhaust guides because the oil from them does not go through the combustion cycle when you had the manifold off was the oil running off the valve stems or coming out around the valve
it is clear that I have tested the engine: without exhaust manifold without valve cover without air filter I disconnected each of the diesel pipes (with the moltore on) It could be that the intake valve guides are very damaged and the oil passes into the combustion chamber. Hypothesis only. Looking at the engine without the valve cover, with the engine running, I see no problems and I don't see all this oil. Of course I couldn't try the engine at full throttle, this is because the oil would go everywhere. About halfway through the throttle a lot of blue smoke. So, I decided to disassemble. I have to see .
What would happen if the engine was run with exhaust valves too tight? I would guess they'd warp seat or stem. If the guy ahead of you then reset the valves. What would happen? Warped valve or stem would be bad compression and also have bad blow by correct? Could the piston pull in oil through the exhaust guild from having warped valve or stem after the ignition and before the exhaust stroke.
This might help??? Go to page 12 in Shop Talk, then go to page 36 in Cat Sprocket Removal, then look at the pictures, your slobbering cylinders should have healed up after a few hours hard work unless it has pistons like this. tctractors
You mean this one Tony..? HeavyEquipmentForums
Tony I can see how some buggered up pistons can still be going up and down with the help of lots of oil! Shawn
This was reported to be a Rebuilt Engine, so I was slightly shocked to find this damage, the engine ran well just heavy on the oil. tctractors
Hi guys , this and the 951c As you can see in the last photos, to remove the plate under the oil sump, it is necessary to lift the engine at least 3 centimeters to remove the bolts. Unfortunately . I did not understand the pin that should close the rocker arm shaft, from the oil spill. Where is it ?
A video of this engine running at idle and fast idle is needed. Something isnt making any sense to me.
Hi guys , here, I created a private video in hd. If you look at it all you can see and hear the strange sound of the engine. He seems to be coughing. I also framed the exhaust manifold and a few minutes already a leak. As already mentioned, no blow by even at full throttle. This makes me suspect. I have seen engines, and usually bad rings give a very evident blow by. So listen to you experts who surely have much more experience than me. I'm planning the disassembly. I'm taking some time. So, if a piece of advice comes up before you take it all apart it would be great.
Ok, NOW this is making some sense! 1. The engine isn’t running smoothly, it’s missing a cylinder. 2. The smoke you are seeing is unburned fuel from a dead cylinder. 3. Are you positive that is oil that is leaking? Could it be carboned fuel? 4. I’m suspecting several possibilities. A. The injector nozzle on #3 is junk. B. If above is the case, that cylinder is washed down and can’t build enough compression to burn the fuel. C. Washed down cylinders sticks all the rings allowing oil to pass the piston. D. Possibility of a burned valve or broken seat. At the very least you will need to pull the cylinder head. You can replace the nozzles as a cheap check but I’m afraid it’s too late.
Holy sheep shitt ,If this is a good sounding motor I would hate to see a bad one. Sounds like a piston is trying to swap holes. pull the head and see what the carnage may be. Bob
Turn the Fuel tap off at the tank, follow what I said about jacking up the engine and drain down the water from the block and rad, by the sound of the engine it's about due to swallow a valve, when you get the pan off pin the Flywheel at TDC and check the Lanchester balance shafts for position by inserting the bolts through the Sump plate,I am not saying they are not set correctly but it will give you a confident lift when you reassemble things as to how they should be, as you will be removing the oil pump to draw off the Sump Plate. tctractors.
Hi guys . In the meantime, thanks to everyone for the support. I removed the cylinder head. The gasket is like new. Before disassembling I eliminated the exhaust. I could see that the cough was coming out of cylinder # 2. During the strange explosion you could see sparks like fire. I could not tell if the oil was coming from the valve guide. The cylinders are mirrored and the pistons are all in all good. I attach video of the valves and images of the cylinders and cylinder head. That blowout ??????
English please.
That 2nd piston pic ....yeah, my money is on that one.
2nd piston looks like it is hitting the top of the head check rod and wrist pin also looks like it has a lot of burnt oil built up on it
Or better yet that clean edge around that piston is caused by the unburned fuel leaving that cylinder with the compression. It needs to come out…….I’ll bet it looks like that piston pic Nige posted earlier.
This engine looks well stuffed, the valve guides can be hit out but better to press them out, i would be removing the engine myself as they come out easy enough after removing the nose group, you can just unbolt the hydraulic pump and leave it in the frame still connected. tctractors
I removed the piston 2. It seems to me in excellent condition. The rings are like new. I have not found any anomalies. I think all that oil comes out of the valve guides .... I think.
Remove the oil control rings and put them in the bore of each cylinder (where each came from). Use the top of the piston to align the ring and measure the ring gap. It looks like the oil ring edges are scraped out. You can do the same with your compression rings. Post the measurements.
Also is it just me or does that piston look strange up near the top? Red arrow in picture below: Been a few years since I worked on a D333 or 3306 but don't recall a piston that looked like that! Maybe a little cutting from the carbon like the black streaks but there apears to be a large amount of material missing on that side.
Looks like a burn
That's called a valve relieve or eyebrow pretty normal . Bob
Sergioannis I think you are right that piston and rings look new. Do you know the history of this engine? almost looks like a valve guide broke and went threw the piston. Any more valves loose? How about a picture of the valve guide and the top of the liners? Bob
That's the problem with only seeing a picture and not having it in hand! From that angle I was thinking the top of the piston was eroded away. Going back to see piston from top I can see the reliefs, but still looks a little rough around the outside diameter. Then again pictures can be deceiving!
Hi guys I cleaned the piston. It's new. it has a dent, I think something got in from the side of the air filter. For the rest I don't know what to say. I believe the cylinders are enamelled and the oil rings don't work. There is no crest on the cylinders.
Have you pulled the valves out and cleaned them? Do you have spec's for the valve guides and valve stems? Just incase you don't Ill attach a .pdf for them:
Are the valves and valve guides for that cylinder intact.? No small pieces missing.?
n wiggle the valve in the guide it is too lose
When I clean the valves I expected a lot of coal. Instead, with the drill, a rust color came out. The residue I removed looked like sand-colored flour. Could it be dirty fuel? I didn't find any kind of crack in the valve guides. it is likely that something has entered in the suction phase, some stone that has struck on the head .. I think all this regardless of oil consumption and oil leaking from the exhaust. I have to admit that the engine is in very good condition, I'm talking about the pistons, cylinder head and also the cylinders. I think he did not have too many hours. What to say ....
I'm with Bob on the vale guide being damaged and sending little bits down stream. The vale you you were moving around looked like a friend that needed a ride home. Also looks like you could pour some good oil past that valve. Time to take a good look before putting it back together. Seems like there maybe some good parts after your brush from out in the field agony.
I would say that is sand colour is normal and indicates good combustion. Black deposits would indicate poor combustion. Because your problem is recent there has not been the opportunity for black soot deposits to accumulate.
Ho misurato i cilindri. Diametro sotto la cresta 120,69mm Ho trovato un modo per rimuovere la piastra sottostante. I pistoni, le bielle, le boccole sono davvero in ottime condizioni. È probabile che abbiano rifatto il motore senza cambiare i cilindri. Tutto il resto è nuovo. Basta guardare la guarnizione della testata che è come nuova. Ho ordinato le nuove parti. Guide valvole, kit anelli. Posso riutilizzare la guarnizione della testata secondo voi?
[QUOTE="sergioannis, post: 984693, member: 75065 I would use a new head gasket. Check the valve guides to see if they may be broken. The liners show they were rusted a little when you started the engine. Not seeing it I would guess the oil was coming threw the valve guides. Bob [/QUOTE]
The cylinder sleeves should be removed and the outside checked for excessive pitting. If good, de-glaze the inside, replace the lower liner seal rings and re-install. Check the liner protrusion before removal and after re-installing. Use new piston rings and rod bearings although the old rod bearings MAY be re-useable. After all, you have gone this far so you might as well do it right. Maybe even check the main bearings too. If the pitting(rust marks) on the inside of the liners does not clean up after deglazing you will need new liners in my opinion if you want it to last a long time
Absolutely. If the antifreeze in the cooling system was not good there could be a lot of damage on the outside surface of the liners that could cause problems in the future.
Is this bit of wisdom like the bad turbo and the busted piston? Bob
If you tilt your head to the right about 15 deg's. it looks like a bears face/head on the piston.
Also check the lower bores in the block they are known to erode too
Bob. In the words of the great prophet. **** off.
Not seeing that! more like M-i-c-k-e-y M-O-U-S-E.
Is this the best you got? I have a 12 year old grandson and he has better comebacks. This is one of the draw backs of being a parrot when you regurgitate you have no idea if its a pearl of wisdom or a pile of steaming horse apples . I can send you a hurt feelings report if you want and you can fill it out and turn it in to HR. Bob
I wasn't aware it was a competition. I'm only the latest in a line of members on this forum who have used the exact same two words to you over the years. There seems to be a pattern and the finger of suspicion as to who's responsible isn't pointing at me.
Just thought it worth the Verbs, on the Con Rods they are marked with an I to show the correct fitment with the I to the front of the engine, the cylinder liners should be clamped into the block and hight checked before any seals are fitted to them, the top flat seal (Filler Band) on the liner has to be soaked/dipped in engine oil and then fitted to the liner when installing them, always tap out all the head bolt holes in the cylinder block, don't be scared to fit a new suction screen to the oil pump as the mesh is very small and they are often pegged up, the head bolts are set to the lower torque than the spacer plate engines, I think it's 175 Ft Lbs (please Check) tctractors.
Hi guys. I shot a video, for those interested in seeing the disassembly and hd details of this engine.
sergioannis good job with the video! Your showing all the steps along your way. It should help plenty of folks see wat it takes to do the job on a 951 or if they're thinking of pulling apart a 3304.
Hello I wanted to remember, that in order to remove the underlying plate is only necessary to unscrew four bolts which hold the engine side, two on each side. Then you have to disassemble the rubber biscuits. Not completely but only on one side (that of the converter) are 8 bolts. At the front, unscrew 4 bolts from below (2 per side) that hold the engine to the frame. You don't have to disconnect anything else. With a jack, lift the engine 2/3 centimeters from below to allow you to remove the bolts that are under the upright. Time required for this operation 15 minutes
That would be 15 min. for you! If I could only keep up with you Guys from over the Pond! You, Chris, Spyros, and the Firm. I am What you say living Vicariously thru you Guys, and the guys back here in the States. Great to see these Loaders being put back in Shape!
Maybe those are "Metric Minutes"?
Hi guys . It took me 15 minutes. They are 4 bolts, spanner 24. Below there are about 10 bolts, wrench 14. With the electric unscrewer it took me very little time. It seemed like a challenge to lift the engine, but it is really easy. Of course, considering, removing the underlying plate, oil, oil pan etc takes a long time. I was just referring to disconnecting the bolts and removing the cookies to lift the engine a few inches.
To undo the Drive Cookies can be a fair struggle as sometimes the bolts need a spanner all the way off, plus to crack them free can take a good arm full of power, your engine seems to be in fare condition piston wise, have you measured the piston ring gap,you will need to mark the 2 top rings for TOP position if you remove them, the valve guides looked to have massive wear so will need a new set of springs, valves and guides, also the valve seats will need a trim on the 2 angles, tctractors
Hello . What do you mean ? How should the position of the new rings be?
I think what TCtractors was getting at is assuming the rings were installed correctly the first time the markings for top might not be visible now with a little running time. So just use something like a marker pen to mark which side goes up. There is an up and down to many piston rings that might not be easy to see or measure without lots of effort and knowing what to actually look for as the differences would be near impossible to measure but if installed wrong would cause all kinds of problems!
tctractors is quite right right about marking the rings and checking the end gap. Whether you replace the rings or not, I think some one said to be sure to hone the cylinder out so the rings will seat themselves properly in the bore. Also if there is a ridge at the top that should be removed so you don't damage the top ring unless you put back the same used ring in the same used piston in the same bore. If your going to get new piston rings you should measure to see if its been bored over size. If it has get the rings to fit that bore. When you get the rings put each of them one at a time in the bore (preferably in the same bore you'll be putting it in). Use a piston to push them in straight. The Cat book will tell you the end gap, you measure it with a feeler gauge. I think most all piston rings have a top and bottom and should be marked by the maker of the ring. I'm still concerned why a short time engine could be so screwed up? Like kshansen said, the rings could have been put in upside down by the guy before you. See if you can find the root cause. Could be it was run with 10W and a bad sensor. lol!!! Best of Luck
The 2 top rings are marked from new for position, after 10 minutes of running the etched Top marking would be gone, the oil control ring is not usually marked for fitting but depending on make can be narrow or wide so the ring needs to fill the grove totally, the possibility of the liners being bored over size is not really on the cards as the liners are very low cost, plus a piston part number check will soon cover this point, the piston has a V mark on the top that will point to the V mark stamped on the cylinder block, I have already said the Con Rods are marked for front so make sure they are fitted correctly as the piston pin is off-set from mid position to stop reverse start up. tctractors.