I purchased A L 4330 which had experienced and over heating and a frozen engine. The heater hose had ruptured which led to a failed head gasket with antifreeze on top of one cylinder. I am having the head magna fluxed and a valve job. After removing the head I noticed that on one of the cylinder walls there were deposits of what appears to be aluminum from the piston. My question is should I remove the piston and inspect the bearings. There appears to be no bent connecting rods or any other damage.
Piston Metal on Cylinder Wall
- Thread starter wdlanning
- Start date
85Hokie
Moderator
Staff member
Lifetime Member
Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
I am no expert - but are those sleeves? and i would imagine they will need to be driven out and replaced.
With the engine broke down - I would check EVERYTHNG ....... and not take shortcuts coming back together.
With the engine broke down - I would check EVERYTHNG ....... and not take shortcuts coming back together.
At the very least you should pull the pistons, clean up the cylinder with a hone, (give it a good cross-hatch and measure it for diameter, choke, and out-of-round while you’re at it.)
Install new pistons and rings.
You don’t say how many hours on the engine, but if less than 2K or so I’d not touch the crankshaft or main bearings if a visual inspection doesn’t reveal hot-spots or bearing-injury. (However, a plasti-gage look at the one of the mains and con-rod bearings would be easy since you’ve got the bottom opened up to get the pistons out.).
So, Yes!... clean up those cylinder-walls and new pistons/rings are a must.
Install new pistons and rings.
You don’t say how many hours on the engine, but if less than 2K or so I’d not touch the crankshaft or main bearings if a visual inspection doesn’t reveal hot-spots or bearing-injury. (However, a plasti-gage look at the one of the mains and con-rod bearings would be easy since you’ve got the bottom opened up to get the pistons out.).
So, Yes!... clean up those cylinder-walls and new pistons/rings are a must.
I appreciate your quick and thoughtful response. Just to be clear are you suggesting that all 4 pistons and rings should Be replaced based on the metal deposits on the one cylinder?
That’s the only cylinder I saw.
However, the “heavy work” of removing one piston ...would be the major portion of replacing them all. I would probably consider it false economy not to do them all while I’m in there.
However, the “heavy work” of removing one piston ...would be the major portion of replacing them all. I would probably consider it false economy not to do them all while I’m in there.
85Hokie
Moderator
Staff member
Lifetime Member
Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
I would agree with Geo - depending on what "happened" inside the cylinders ..... having them all "fixed" will cost not a lot more than getting the one fixed - I don't think you want to take a short cut here.
Take the entire engine down - and then measuring everything and check the specs via Kubota - then you can decide what is best course of action.
Unless you are proficient in rebuilding - I would take it to a diesel mechanic and see what they say.
On a big two stroke outboard which had a piston partially seize to the cylinder, the dealer used a special acid to remove the stuck on aluminum so the bore would not be increased on the one cylinder. Must be a trick known to those who rebuild engines and worth asking about.
Dave
Dave
that engine needs to be machined
the cylinder is junk, so is the piston. check the head for cracks!
that is classic case of severe overheat. The aluminum on the cylinder wall is called metal transfer, and is a result of lack of clearance + excessive heat from friction. The aluminum from the piston is friction welded to the cylinder wall. Generally speaking the cylinder wall is now out of round and/or tapered; neither is any good. It is likely to have to bore the cylinder(s) to oversize so that they are round and square again. Very common. Seen it many times. I have on occasion been asked to reassemble the engine after a hone, and 100% of the time it is not right and then the customer puts my name out all over the web saying how bad of a mechanic I am, also failing to tell the whole story. Had they done it correctly they wouldn't have had to waste that time.
Yes I understand and respect the cost thing. It's gonna cost more to strip the block, bore & hone, then buy new pistons/rings. But I also understand doing things correctly the first time if at all possible.
Check the head for cracks. They crack when overheated.
the cylinder is junk, so is the piston. check the head for cracks!
that is classic case of severe overheat. The aluminum on the cylinder wall is called metal transfer, and is a result of lack of clearance + excessive heat from friction. The aluminum from the piston is friction welded to the cylinder wall. Generally speaking the cylinder wall is now out of round and/or tapered; neither is any good. It is likely to have to bore the cylinder(s) to oversize so that they are round and square again. Very common. Seen it many times. I have on occasion been asked to reassemble the engine after a hone, and 100% of the time it is not right and then the customer puts my name out all over the web saying how bad of a mechanic I am, also failing to tell the whole story. Had they done it correctly they wouldn't have had to waste that time.
Yes I understand and respect the cost thing. It's gonna cost more to strip the block, bore & hone, then buy new pistons/rings. But I also understand doing things correctly the first time if at all possible.
Check the head for cracks. They crack when overheated.
Based on recommendations I am going to split the tractor to have easy access. I could lay under it long enough to remove one piston but this back of mine won’t tolerate much more. Besides if there is additional work, may have to pull it anyway
Many thanks for your responses
Many thanks for your responses
Be sure to put wedges between the engine and the front axle when you unbolt the engine or it will flip to one side or the other.
Just muratic acid. You can pull the piston, wipe the sleeve and it will eat the aluminum and leave the cast iron alone. It will also dissolve you so be EXTREMELY careful if you do this. You should still clean it up with a hone.
yeah muriatic. Strong stuff and I've used it in the past. Use it outside a mile or so away from your metal building, cars, trucks, anything steel or aluminum. Also do not smoke anywhere near it because the reaction gives off hydrogen (explosive). And...the fumes from muriatic will kill you dead. Breathing protection is a must. Your block's metallurgy is also damaged, and will RUST immediately after washing it down. WD40 won't stop it from rusting. Nothing will but putting it into service immediately after washing it, in my experience. Get the stuff in the water jackets and the coolant will turn to rust quickly, and there's no fixing it. I have used it in the past on engine blocks and I won't use it anymore. I'd just as soon carry the block to the machine shop and let them bake it out before doing the machine work necessary. A lot less dangerous and a lot less headache in the long run.
muriatic works but it doesn't solve the fact that the cylinder is likely junk.
again once metal transfer occurs, there is good reason why. The piston makes contact with the cylinder dur to expansion and/or lack of lubricating oil. When it happens the cylinder is almost always trashed. Putting new pistons into a oblong or tapered cylinder is not a good thing to do. Neither is putting new pistons into a block that has excessive bore size, results in much reduced engine life. This is a big job. If one goes through pulling the engine,and halfasses the work, a few years later when it loses compression and won't run on one or more cylinders, you'll be second guessing yourself. Why on earth didn't I do it right the first time? Trust me I have been there.
At the very least grab yourself a dial bore gauge and measure the bores after removing the aluminum. The WSM tells you how much taper and oblong is acceptable, and it is not much. Diesels are different than gas burners and gas burning 2 strokes are totally different than 4 stroke. Diesels, especially smaller ones, are highly sensitive to compression pressure and it takes VERY little imperfection in the cylinder walls, pistons, rings, head(s), valves, gaskets, etc to cause a compression loss--results in hard starting, or no-start. And then ya come back in this forum asking why it won't start when cold, and 5 replies saying your injectors are bad the pump's bad or you're using the wrong color hydrualic fluid causing your engine to stop running.
muriatic works but it doesn't solve the fact that the cylinder is likely junk.
again once metal transfer occurs, there is good reason why. The piston makes contact with the cylinder dur to expansion and/or lack of lubricating oil. When it happens the cylinder is almost always trashed. Putting new pistons into a oblong or tapered cylinder is not a good thing to do. Neither is putting new pistons into a block that has excessive bore size, results in much reduced engine life. This is a big job. If one goes through pulling the engine,and halfasses the work, a few years later when it loses compression and won't run on one or more cylinders, you'll be second guessing yourself. Why on earth didn't I do it right the first time? Trust me I have been there.
At the very least grab yourself a dial bore gauge and measure the bores after removing the aluminum. The WSM tells you how much taper and oblong is acceptable, and it is not much. Diesels are different than gas burners and gas burning 2 strokes are totally different than 4 stroke. Diesels, especially smaller ones, are highly sensitive to compression pressure and it takes VERY little imperfection in the cylinder walls, pistons, rings, head(s), valves, gaskets, etc to cause a compression loss--results in hard starting, or no-start. And then ya come back in this forum asking why it won't start when cold, and 5 replies saying your injectors are bad the pump's bad or you're using the wrong color hydrualic fluid causing your engine to stop running.
i just pulled head off the b6200d and found a washer in the number one cylinder . pulled all 3 pistons and the front cylinder had a hair line crack . off to the head sop and getting valve seats cleaned up ordered one piston 3 sets of rings rod bearings valve that was twikked by the washer gaskets etc. what type of hone should i use on cylinder walls the the company that sells the flex hone has very detailed info for all engine blocks? THE FUN JUST NEVER STOPS !
measure the bores. if they are not tapered and not egg'd or not scratched you might be able to hone. remember honing removes some material so keep that in mind.
i have new piston a new intake valve 3 sets of rings and rod bearings on the way from messicks . the two dealerships i talked to were way out there for prices and advice. at least this blog has people you trust for the problem on hand and not trying to make a buck on my lack of diesel tractors. so what flex hone do i need to cross hatch all three cylinders? the metal the d-850 engine must be steel and pistons cast aluminum.
My advice, you need to measure the bores for wear and taper. If you don't have the tools find someone who does. There will be a spec on the piston to cylinder wall clearance, either buy a service manual or call your dealer to find what the spec is. If the bores aren't worn out, yes all the cylinders will need to be honed. If you haven't done it find a mentor.
with that smeared aluminum on the wall, you can bet some of that is in the ring lands and has frozen the rings too. You ar half way there, so go ahead and do a complete teardown. And I would be surprised that you do noty have a bent rod.