I finally got a chance to look at our D8. I fired it up and instantly got a black sooty shower that tasted sweet. The oils is black. I was thinking of taking a 2 inch copper tee and putting it in the return line to pressure up the cooling system, is this a good idea? I already have a used tee with I/4 inch pipe thread where a gauge went so I am not buying one.
Do you have an overflow tube off the radiator? that is an easy way to pressurize a cooling system. It doesn't sound like you need to hold a certain pressure overnight, as much as add some pressure, feel the hose is firm, and see where the coolant goes before it leaks off the pressure. If you need to put a gauge on it, I'd find another port on the engine before I'd try to cut into the hose, that's just me.
Just by indication of heavy soot and sweet sounds like a cracked head in a exhaust port area with a coolant seep allowing a-freeze to disrupt/lift the carbon layer in the manifold. If you have the time and do not need the machine apply pressure on the coolant side with the exhaust manifold off after running the engine to full op temp. If there is a seep into the exhaust it would show there. This is if you have not experienced a hydro lock at all on the engine, a hydro lock would indicate coolant getting into a cylinder.
Today I went and removed the heads on the D8. It was low on coolant and by the volume of water that came out the other day I was afraid that I could bend a rod if the cylinder was full of water. Number 1 and 2 pistons are clean. The intake manifold had water in it as I took it off. I figure I will take it to a machine shop and have the heads checked out. I talked to a mechanic from ALtorfer and said if I had everything cleaned up it would only take 3 or 4 hours to get it back together. He also said he might know of someone having some used heads. Obviously I don't want to spend any more than I have to but I don't want to do it again. Is there any advise on if I am approaching this wrong? As a side note the other day when my son was running it when this happened he said it didn't have much power.
I would suggest turning the engine over by hand and checking the liners for scratches. The other thing to check is the liner protrusions. How did the head gasket look when you removed it?
John nailed it, on those engines the counter bore could crack letting the liner down, if that happens there is nothing for the head gasket to seal against and they would usually leak compression into the water jacket and out the overflow. Well worth checking
I steam cleaned the heads and the front head is very concerning. The dozer is out in the pasture and I haven't had a chance to look at it. I am going to take the heads to a machine shop and get checked out. All the precombustion, chambers are tight. A cat guy gave me a spline remover but it is the wrong one and couldn't remove them. When I removed the heads I greased the cylinders and block top as well wrapped in duct tape and plastic. Is there any thing special about measuring the liner protrusion ? Also when I was cleaning there was silicone along the side. Any comments are appreciated.
I steam cleaned the heads and the front head is very concerning. The dozer is out in the pasture and I haven't had a chance to look at it. I am going to take the heads to a machine shop and get checked out. All the precombustion, chambers are tight. A cat guy gave me a spline remover but it is the wrong one and couldn't remove them. When I removed the heads I greased the cylinders and block top as well wrapped in duct tape and plastic. Is there any thing special about measuring the liner protrusion ? Also when I was cleaning there was silicone along the side. Any comments are appreciated.
As for that silicon, I going to guess that there was some oil seeping there someone thought smearing a little on the side would "fix" it up good. As I believe the only thing in that area is the oil draining back from the rockers it was probably mostly a case of an old tired head gasket. If you need spec's on liner protrusion I could probably find them on SIS. Usually we just used a puller bar across two head bolts or studs to snug down to clamp liner and measure in as many places as you can.
From your picture, the cylinder on the left and the one in the middle has been burning coolant. I use a depth gauge to measure sleeve protrusion, but you can use a straight edge and feeler gauge. Be sure to bolt down the liner in 2 places before you measure. Need to measure about 4 places around the liner. I think there can only be 2 thousandths tolerance per hole, but the service manual will be your guide. Sometimes, you can spin the liner in the hole if it's a little out of tolerance and re-measure to attain the right protrusion if you are reinstalling the liner. Then again, there is a certain tolerance maybe 4 thousandths along the entire engine that is the maximum difference between liner heights that cannot be exceeded. Again, refer to the service manual or an expert here. Just giving you the procedure. Look at the old head gasket to see if it was leaking combustion gases. Take it to your machine shop or your buddy at Cat to assess. Also, look around the deck to see if you can see carbon traces where a leak was occurring. You need to find out where that coolant is coming from. Those shiny pistons are an indicator of coolant washing the carbon off. I'd remove those precombustion chambers and check for pinholes caused by cavitation. My machine shop has to have them out anyway to pressure check them, so a good time to do it. Removal tool should be a 5F8353. It could be a cracked head or a liner that is too low or cracked cylinder liner in the combustion chamber. There is a metal seal underneath that liner in what's called the counterbore. If combustion gases escape underneath it, it can erode a path in that counterbore. Then you have to remove the liner and have a machine shop come out and recut your counterbores along with re-shimming them to get the right protrusion. http://www.ebay.com/itm/5F8353-5F-8...ol-for-Caterpillar-Applications-/251419554419 I believe somebody was trying to hide a bad sealing head gasket with that silicone. Check the block deck and cylinder head for flatness. Where's ol' tctractors when you need him for advice? He's done a thousand of these engines. I bet he could throw some verbs at us.
Thank you, when I pulled the heads I didn't realize the liners would "float up". That is why I could not figure out how to measure them. I bought a service manual off ebay and even talked to the guy about my serial number and he said he had one. The service manual only goes to 10000 something. Apparently the engine as been replaced in this dozer as its serial number is 24035 and engine number is 19905. Should the liner hold down bolts be torqued or just tightened? I cant thank you guys enough!
Just tighten them.
I used to torque them to around 50 pounds just to make sure they were down even. If everything is clean like you're putting new liners in a clean block just snug works. You will have to clean up the tops of the liners with some fine abrasive cloth first and I usually cleaned the block the same way where I was going to do a the measurements. I don't know where the serial number break was on those engines but there were a high horsepower and a low horsepower versions. The low horsepower units usually had the hydraulic tank mounted under the radiator while the high horsepowers had the hydraulic tank mounted next to the operator on the right side. I don't know where your manual is going to fit.
d9gdon, Glad you have a manual, as I took a look at SIS and all I can see there is parts breakdown info.
If you PM me your phone number I can share a few tips on these engines. Bob
Bluox I do not know how to do that.
Click on "Bluox" in the box on the left, then click on "start a conversation".