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Do you have a decompression mechanism? If so, make sure it is connected properly and not locked in the decompress mode. I had difficulty getting it reinstalled properly when I had the valve cover off. The engine should spin freely with decompression open and “chug” on each compression with it closed.
Flooding is a definite possibility based on what you describe. Pull the fuel cut-off and hold it while spinning the engine over. If you have a decompression system and it is working properly, hold that open too while you spin the engine. Doing this should purge the excess fuel from the cylinders and allow you to “start over” on the start sequence.
Valve timing is determined by the gears under the front cover, If you didn’t have that apart it is not likely to be an issue. Did you replace the valve push rods to their original positions?
My tractor likes a little glow plug on the first start of the day, no matter how warm it is outside. The glow plugs are on the left side of the valve cover and are all connected to each other by a copper or brass buss bar. If they are working properly you should see a huge amp draw on the gauge as you hit the key position just before the start.
My start procedure is to hold the fuel cut off and decompression levers, hit the starter and let the engine spin until oil pressure comes up on the gauge. The release the fuel cut off and set the hand throttle to about 1/4 to 1/3 open. The hit the glow plugs for 15 to 30 seconds. Then hit the starter and let it hit max RPM before dropping the decompression lever. That way you have the mass of the flywheel helping to overcome the compression strokes. It usually starts in just a couple of revolutions.
Sounds to me like you will be an “engine guy” when this is all said and done. 🙂
There will be a specific order for the piston rings, and there will be a top and bottom for each ring. The lowest ring is usually actually a set of two rings with a wavy spacer in between. This one is for oil control. The rest are considered compression rings. Looking at the parts book it looks like the top most ring is one part number and is different from the middle two, which are the same part number.
Typically when you assemble rings you stagger the gap before putting them in the bore. You will need a compression tool to squeeze then down to size as you push them into the sleeves. I think it is standard to apply some engine oil to them and the sleeves before inserting them.
Speaking of sleeves, I believe there is a specific amount that they are supposed to stand above the the block when fully installed. I remember seeing someone reference “deck hight” before but don’t know enough about it to give any advice on the subject.
On a gas engine I overhauled we used a 50/50 mix of engine oil and STP oil treatment as an assembly lube. The theory was that the STP made the oil sticky enough that it stayed put through the assembly process and then was easily washed away when the oil pump took over. Never had any issues with that engine so I have to assume it worked. I don’t know what is recommended for this engine but something like that couldn’t hurt (I would guess).
Good Work!
There is always the possibility that these pistons were faulty from the start. It is also quite possible that someone who didn’t know what they were doing used starting fluid on the engine and did this damage.
If you have someplace nearby that can magnaflux the head it might be a good idea to have it checked. Replacing all 3 is a good idea as there may be damage in the 3rd one that you just can’t see. No sense in going through all that again for the price of one more piston/sleeve.
I don’t know enough about overhauling one of these engines, but I would check with Circle G and see if they think you should replace the head bolts. Sometimes head or con-rod bolts are designed to stretch a certain amount when torqued and then are to be replaced if they are ever removed. I doubt that level of sophistication on these engines, but it won’t hurt to ask.
I did not expect to see that. Here is a scan of my parts book and it shows a gasket that looks like what you have. Call out # 10.
Take a look and see if what is in the book looks like your gasket. I have never had these parts off of my engine so don’t know what it’s like inside.
It may be that the gasket is designed to act as a baffle. The air enters through the slot, then has to travel sideways between the gasket and the cover to get to the breather tube.
Yes, that gasket could have been the problem. I didn’t catch it in the photo the first time I looked. I have a snowblower that has a reed valve in the breather. It froze up one time and caused oil to spit out everywhere!
If you leave the thermostat out you can see immediately if your pump is working and that is fine. Just don’t work the tractor without a thermostat as it will overheat without one. I know that sounds counter-intuitive but without the restriction provided by the thermostat the coolant does not stay in the radiator long enough to shed the heat it picks up in the engine.
I would confirm the function of the thermostat in a hot water bath and then put it back in if it works properly. I am lazy and cheap so I would put it back together once but use plain water for testing, not wasting the anti-freeze until I know it won’t be wasted. 🙂
In my experience most cooling problems are the thermostat. Fortunately on this engine you only have to drain about a gallon out of the system to lower the level far enough to replace it. If the top hose is soft you don’t even have to take it off the housing and if the gasket is fresh you can probably re-use it.
Watching through the radiator neck (make sure the cold level is just above the tubes) from cold start up to full temp will be quite telling. If your thermostat has a small bypass hole you should see a little circulation even when cold. If you have an IR thermometer it can show the temps as heat transfers through the engine. Temping the exhaust, head, thermostat housing, block and radiator would be something your kids might enjoy (educational too).
The thermostat/housing/bypass setup on this engine is the weirdest thing I have ever seen.
The factory thermostat is supposed to block off the bypass circuit when it is fully open. I have never seen this kind of setup before and the only thermostat that will do this is the factory one. However, from the measuring I did, the fully open thermostat wouldn’t touch the bypass hole in the housing anyway. There was also a bypass hole drilled in the thermostat itself so I don’t understand the redundancy here.
I wanted a warmer thermostat so had no other option than to go after market. I have a chart of after market parts that cross over. However the number listed for NAPA did not exist but the counter guy found one that looked like it would work. In reality it was ever so slightly too big of a diameter. I had to sand/file it down just a little to get it to fit properly.
The bypass is open all the time but now my engine will warm up to the proper operating temp without putting cardboard in front of the radiator. I have yet to work it really hard on a hot summer day so there is still that test to be done.
On a side note, I tested the old thermostat and it was opening fully at about 150° F so it definitely was the problem.
The spring you identified is definitely not part of the hose and I can not think of a reason for it to be in there. I would say take it out if possible as if it comes loose on its own it could wind up in the pump.
I also recommend putting anti-sieze on the bolt threads when you re-assemble. One of the bolts on mine was rusted to the housing and broke off. I had to take the housing off and drill it out and heli-coil it. Not hard to do but a pain in the rear that can be avoided.
My 2006 Jinma 284 came with a flat steel screen that slides into some tracks along the front side of the radiator. It has a little handle on the top so you can pull it out for cleaning. The holes are punched out and round. While protecting the radiator fins it does add some resistance to air flow but has never caused overheating unless plugged with debris.
Does your radiator have a fan shroud on the back side?
I am not sure if you can see light all the way thru the radiator fins. I will check later today when I get to the shop.
These radiators are extremely thin! be VERY careful cleaning it. I would recommend against using a pressure washer as it can not only easily fold over the fins it could possibly cut thru the core itself. I blew a hole in mine just by putting on a cap that was rated too high.
Look down inside the filler neck and see if the rows of tubes are off-set or or if they are all lined up from front to back. If they are off-set it may be difficult to see light through the fins and water sprayed on will have to weave its way through the fins and will come out looking like it is blocked. With so few hours on your tractor I doubt the fins are blocked too badly. Just use an air hose from the back side to blow any dust back out the front.
Replacing the radiator is not hard but it is a bit of a pain so I would avoid that if possible.
How does the inside of the radiator look? Do you see a lot of white corrosion build up around the core tubes? If not, it is probably fine. This is where tap water attacks the system. Use only distilled water and anti-freeze for diesel engines. For trouble shooting purposes you can just use plain water but for long term health of the system you want the coolant mix.
Thermostat in next post…
As for cleaning the fuel tank, I would recommend using a foot or two of small chain. It is much easier to get out than a bunch of nuts and bolts. If you can get the holes all sealed up you can also put a little diesel fuel in it to help during the tumble process. I think the tanks were just bare steel inside to start with and they are fairly thin so be careful trying to get all the rust out.
Moisture in the fuel tank can lead to problems much worse than a little rust. Diesel bugs make a terrible mess and do significant damage to everything inside the fuel system. There have been lots of threads on that so I won’t re-hash it here.
Side cover and breather should be an easy fix for you. I would use some sand paper on a hard block (just wrap it around a piece of wood) and sand the mating surfaces down to shiny metal. It doesn’t have to be perfect but clean and smooth is helpful for the new seal. You can order a new gasket, or buy some gasket material and make your own or just use RTV sealant. Personally I would probably make the small two hole gasket and use black RTV on the larger side cover. This is not a high pressure or submerged situation and it should work just fine.
Radiator continued below…
Dave, agreed. I would be in no hurry to take things apart until we had more of an idea as to why.
The coolant issue and the oil spitting issue may or may not be related. At this point it is sounding like two different problems.
The radiator shouldn’t be corroded at these few hours unless it was filled with tap water and had no anti-freeze or protection additives. I’ve seen tap water do nasty things to coolant systems.
If it will run without overheating I might even be inclined to remove the dipstick and put a cap over the tube to seal it. Might have to clamp it in place. That way you could carefully monitor oil consumption without it being pushed overboard.
The more hours you can get on the oil and coolant the more accurate an analysis will be.
Which leads to one more thought, although a little off topic. I wonder what kinds of fluids are in this machine. If the original stuff from China, they need to be changed. The stuff that was in my tractor in the crate was horrible stuff.
