My new 4300 project

[larboc]

Got my engine block reinstalled today now to start adding all the exterior parts like the pumps. The machine shop assembled all the interior parts including the gears so I never got to see the timing marks.

Dang, by any chance if you talk to them again could you ask? I'd like a little piece of mind on the subject.

 

[larboc]

Loving the tech manual again, putting the 2 hydraulic pumps on it seems there are no gaskets between the pumps and the engine. Also the rear of the 2 pumps has 3 different length bolts, but nothing saying which ones go where. The 2 long ones are easy to figure out but the 2 short ones are not the same length but nothing says which bolt which hole. It might not matter but I don't want to screw something up.

Should be gaskets between them, may not have come with your kit but there were gaskets on mine. The gaskets stayed stuck to one side so I just put a light coat of RTV on them and reassembled. No leaks. I wouldn't want to run without a gasket and just use RTV as the gaskets are pretty thick and might affect the gear mesh/shaft clearance between pumps. I think you're looking for part number M805696.

JDparts is as useful, possibly more useful than the manual. Some of the bolts have lengths given, otherwise you can look up the part number on google and get a length if you get lost.

 

[larboc]

Sorry to hear of the gasket failure. Did you use new head bolts? I did not, tho on newer engines,
head bolts are designed to stretch only once to be torqued properly.

When I did mine, I did not find any aftermarket parts, such as your Maxiforce head gasket. I
suppose it could be just a poorly made gasket.

I did not use new head bolts. The manual only says that the crankshaft bolts and the rod bolts are one-time use bolts. Yanmar manual said the same. I checked torque on all the head bolts before removing them and none of them broke free at 65 ft lbs (torque spec.) which means the bolts didn't stretch. Head bolts which have a torque+turn spec stretch when torqued and aren't supposed to be reused or may only be reused a couple times.

I'm thinking/hoping I found the problem. The bosses for the between cylinder head bolts were higher than the cylinder wall. In a couple of spots I was able to get a 0.0015 feeler gauge under the cylinder wall when going between these bosses with a straight bar. I took a large file and ran it across the entire engine deck and got these spots down to level with the top of the cylinders. Generally 0.0015" across a deck or head wouldn't be a problem but because these spots are only 1/2" away from the cylinder wall, separated by the cooling passage, I'm suspicious the the head gasket wouldn't be able to make it up. I'm going to spray all 4 surfaces with a recommended application of copper spray before reassembling this time.

Steve, if your head is still off you might want to check the block. I first noticed when scraping the old gasket residue off with a razor blade the blade hung up on that boss. All 3 cylinders were similar.

 

[steviep]

Larboc the machine shop I used was KJE machine shop out of Rochester NH. My mechanic was Kevin. All they work on are engines. I did have to take the front off to check the injection pump timing. The main gear had 3 timing marks A,B,and C which lined up with corresponding marks on the other 3 gears. Now to check the top of the block.

 

[larboc]

Larboc the machine shop I used was KJE machine shop out of Rochester NH. My mechanic was Kevin. All they work on are engines. I did have to take the front off to check the injection pump timing. The main gear had 3 timing marks A,B,and C which lined up with corresponding marks on the other 3 gears. Now to check the top of the block.

Did it follow the tooth/groove on the crank gear like this? This is also how I remember mine looking when I tore it down originally. The only reason I question myself is because the deere manual has the crank/idler gear markes lining up as viewed from the front, not as viewed by the tooth/groove.
http://www.tractorbynet.com/forums/...-deere-4300-complete-rebuild-timing_gears-jpg

I got my head gasket back on, and for s&g's I put the pump back to the original timing mark before starting. Fired up and runs perfectly now but with a whole lot less engine noise than after I had advanced it post rebuild. Sounds more like it did originally. I didn't even check the spillover timing. I am suspicious that there was some dirt or air in my my IP that finally worked it's way out after several hours of run time, causing the injection timing to go back to original which was over advanced after I advanced the pump timing by rotating it.

The JD headgasket was definitely thinner than the maxiforce, I could tell when adjusting valve lash, but I don't think there was anything wrong with the maxiforce gasket. I think it was combination of over advancing of the pump and the head bolt bosses being a thou proud of the cylinder walls.

Regardless, the tractor runs better now than it ever has, not nearly as much block noise, and the exhaust smells better. Now on to more fun stuff (hopefully)!

 

[steviep]

I think that is how it looked. I lined the marks up just so I could make sure I had the injection pump timed correctly. hopefully I will have it all together this weekend.

 

[Winmac]

I'm thinking/hoping I found the problem. The bosses for the between cylinder head bolts were higher than the cylinder wall. In a couple of spots I was able to get a 0.0015 feeler gauge under the cylinder wall when going between these bosses with a straight bar. I took a large file and ran it across the.

By bosses are you referring to the block area around the top of the head bolt thread?
The fact that they are proud may indicate that the threads are failing and beginning to pull out of the block, hope not but a possibility

 

[larboc]

I think that is how it looked. I lined the marks up just so I could make sure I had the injection pump timed correctly. hopefully I will have it all together this weekend.

You didn't take the pump sprocket off the pump did you? I think in order to do that you have to pull the IP sprocket off (hole in plate is too small for gear?) which I believe I have read is a big mistake.
http://www.tractorbynet.com/forums/...341057-deere-x495-rebuild-injection-pump.html

 

[larboc]

By bosses are you referring to the block area around the top of the head bolt thread?
The fact that they are proud may indicate that the threads are failing and beginning to pull out of the block, hope not but a possibility

That's what I'm referring to, but the area around that bolt is not connected to the cylinder wall by the casting and the entire boss was high, not just the area around the threads. It's an "open deck" block. The 4 "thumbs" in this picture are the bosses I'm referring to as being a little high.


I don't think the threads are in any danger of pulling or failing, the head hasn't been off enough times to start causing any issues, especially in cast iron. I've seen threads start to pull in aluminum blocks with TTY bolts after 10 or so head swaps, but this head had only been off once when the gasket went.

 

[steviep]

I didn't have to take the 4 bolts off but to remove the injection pump you have to remove the center nut. The gear , bolts and the plate behind it all come out together .