Super MD break in

I have my Super MD all back together and about read to fire it off. I ground the valves, and put new rings in it, amount a few other things. Anyway I have rebuilt many gas powered engines over the years, yet this is my first diesel. Is there any special way to seat the rings? What i have been doing in the past is run it up to temp shut it down retorque the head, this would be within the first 20 mins or so. After this run the engine up to 3/4 speed and vary the rpms around under med load, this would be done for a couple of hours. Then full load and there after. Any thoughts if i should do something diffrent?

thanks

Andrew

You got it right Andy,rn it like you stole it.Aint gonna hurt it as long as there is oil and water.DO NOT SWITCH IT TO GAS BEFORE SHUTTING OFF! this is why the heads crack on these engines. Hoss

as hoss says,your full load is probably the most important operation. you want those rings to expand and be forced into the cyl. walls when she is firing under load at operating temp.if you just idle around the yard not reaching operating temp. the cyls. will get glazed and she will use oil.just make sure they are cooled down good before shut down. absolutly no reason to switch to gas till your ready to fire up next time. another tidbit of info. a diesel runs cooler at idle than a gas which means it will cool off faster.some say to clean out the plugs, thats nonsense also because there is never any diesel combustion at the plugs. if you dont believe it start her up switch to diesel and remove one .

(quoted from post at 14:15:58 02/01/10) as hoss says,your full load is probably the most important operation. you want those rings to expand and be forced into the cyl. walls when she is firing under load at operating temp.if you just idle around the yard not reaching operating temp. the cyls. will get glazed and she will use oil.just make sure they are cooled down good before shut down. absolutly no reason to switch to gas till your ready to fire up next time. another tidbit of info. a diesel runs cooler at idle than a gas which means it will cool off faster.some say to clean out the plugs, thats nonsense also because there is never any diesel combustion at the plugs. if you dont believe it start her up switch to diesel and remove one .

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I think you meant to say there SHOULDN'T be any diesel on the plugs. I checked for blow by with my compression tester and did see a little on a couple cyls.

When our neighbors would rebuild a diesel they would run it about twice as hard as you would run a normal tractor. I remember when they rebuilt their 4020. They pulled it straight out of the shop and hooked it to the moldboard. They ran it like a rented mule on the plow, but I would bet they varied the throttle from half-3/4 on up.

The tale could also be told of the two guys who bought ____ together. One guy babied his for the entire break in so it would be "better" while the other guy drove it like he stole it. The guy who drove it like mad always has more power than the guy who babied it. I have heard this about diesel pickups as well as ATVs.

thanks everyone, i just ran it a few mins this eveing. Everything so far seems to tight. Ill know more when i get it out of the garage and start breaking it in.

thanks again

Andrew

OK, sflem 849 I will try and make it more clear.there is ABSOLUTLY NO WAY you will have diesel compression at the spark plugs in the gas chamber while running on diesel if the little valves are doing their job. that is another reason not to switch it to gas and leave them open because they will warp AND then u will have diesel compression leaking to the gas side. from what you said, yours are leaking ...clear as diesel smoke?

(quoted from post at 18:14:15 02/01/10) OK, sflem 849 I will try and make it more clear.there is ABSOLUTLY NO WAY you will have diesel compression at the spark plugs in the gas chamber while running on diesel if the little valves are doing their job. that is another reason not to switch it to gas and leave them open because they will warp AND then u will have diesel compression leaking to the gas side. from what you said, yours are leaking ...clear as diesel smoke?

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I know mine are leaking. I had a feeling mine were leaking so I did that test to confirm the problem. Andrew's shouldn't if he did a good job on his rebuild. (and I am sure he did)

I thought the manual says to switch to gas to cool with the engine running then shut the tractor off and pull the lever back (to diesel) so that it cools (w engine off) on diesel. I will ask a stupid question, how are you supposed to shut the tractor off?
I have noticed harder restarts if I turned it off on diesel, but that could be due to my leaky decompression valves.