7020 head

I'm confused. To say the engine was "professionally rebuilt", sounds to me like it wasn't done by an AGCO/Allis-Chalmers Dealership....???? So, if it's the first A-C 7020 engine this professional guy ever worked on, he isn't exactly a "professional" on that specific engine.  Is the head gasket blown now?? or this is why it was repaired a few years ago??  HOW MANY HRS ARE ON THE TRACTOR ?? and how many hrs since the engine work?? Did it get pistons and sleeves and main/rod bearings ?? or did it just get a head gasket or different cylinder head ??  It's very doubtful I would ever just install a USED cylinder head on a 7020. At a minimum, it would get pressure checked and magnafluxed for cracks. They are somewhat known to crack on the head surface at the copper injector tube bore. This is especially common if the engine was ever gotten HOT !!  like loose fan belts, low on coolant, etc...........

Can a cracked head as you described be fixed?

Usually on 190XT’s for example the engine oil level is increased by the hydraulic pump front seal and o-ring leaking into the front of the engine. Thus increasing the oil level in the crank case. Interesting the fuel pump causes that also. I am looking at this 7020 as a project, just trying to get some ideas of issues, cost as I move forward. When I finally see it I may walk away from it but I am excited to see it. Just trying to get some idea of cost if I should pursue it.

Barnette head and block carothersville , mo. They forge them then weld and machine. Have not had an issue with any they rebuilt. If a copper sleeve head has been overheated, they usually crack. Also many head gaskets were blamed for electrolysis - 7020s and any engine set at max hp with wet sleeves are very prone to have this issue.

I think i am going to pass on the 7020. Looked at it this morning. Transmission and engine has been gone thru by Agco dealer about 10 years ago. Bottom end of engine was done again this summer but they could not find a good head for it after they found cracks in the injector ports. Had 2 used heads shipped in but both were cracked.

That's what I would co too, go with the early style lot less headaches

Both of the Cylinder Head places in Chapin IL have called it quits. Andy

from what I remember when I did the head on mine thermostat housing mounting holes are the same on all heads!

I think the idea was to keep heat away from injectors as the 301 was getting pushed harder for more power

AC7060IL wrote: What was ACs idea to change the 7020's 301 head to the copper sleeve type? Seems like AC took a step backward?

MACK is that a joke?

The copper is very thin. My point is why would Allis go through all the engineering costs to save a few bucks in shipping weight.


Edited by Lonn - 03 Jan 2018 at 6:57am

A-C didn't invent copper injector tubes. Detroit diesels had been using them since the 1940's on the 2-cycles. If you never overheat an A-C, you'll probably never have any trouble. There are more engines out there that never had an issue than those that did.

ACjack wrote: AC7060IL wrote: What was ACs idea to change the 7020's 301 head to the copper sleeve type? Seems like AC took a step backward?    It was a step forward in reality. It provided a more constant temperature for the nozzles which gave a more consistent fuel density and with a more stabilized fuel temperature you got an improvement in horse power, emissions and fuel consumption relative to the HP.    You'll also note that on the copper sleeved head compared to the head without the copper sleeves the water inlet passages into the head where larger. This increased the water flow into the head for the increase cooling that was needed. This also required that a different head gasket be used, it had enlarged water holes to match the copper sleeve head.

ACJack, Thank you for your explanation. Was the later 301s the only AC engine updated to copper sleeve heads?

AC7060IL wrote: ACjack wrote: [QUOTE=AC7060IL]What was ACs idea to change the 7020's 301 head to the copper sleeve type? Seems like AC took a step backward?    It was a step forward in reality. It provided a more constant temperature for the nozzles which gave a more consistent fuel density and with a more stabilized fuel temperature you got an improvement in horse power, emissions and fuel consumption relative to the HP.    You'll also note that on the copper sleeved head compared to the head without the copper sleeves the water inlet passages into the head where larger. This increased the water flow into the head for the increase cooling that was needed. This also required that a different head gasket be used, it had enlarged water holes to match the copper sleeve head.

ACJack, Thank you for your explanation. Was the later 301s the only AC engine updated to copper sleeve heads?[/QUOTE