Farm Equipment - 7070 overheating

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7070 overheating

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=189125
Printed Date: 15 Nov 2024 at 6:07pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: 7070 overheating

Posted By: Svnty7
Subject: 7070 overheating
Date Posted: 26 Jun 2022 at 4:19pm

I’ve read several posts on here with issues of 7060and 7000 series overheating., And tried all the fixes
I have a 7060, low hour tractor. Never had a working temp gauge until about a week ago. It always ran around 200 with a laser thermometer however it started getting worse. The previous owner had removed both stats. It also had no foam around the rad. I put in new 180 stats, complete foam kit, belts tight. Rad professionally rodded , new water pump, timing at 18 degrees. After putting in the thermostats it overheats within minutes baling hay. It will run about 200 at idle but shoots sky high when running at rpm. I’m stumped and desperately need the tractor. Any help would be greatly appreciated. Thank you!!!

Replies:

Posted By: Hurst
Date Posted: 26 Jun 2022 at 4:50pm

A bad head gasket or cracked head can cause them to overheat pretty quickly. Have you pressure tested the system? Another thing could be a bad radiator cap or another pressure leak keeping the system from staying pressurized. The coolant system needs to stay at pressure to circulate properly.

-Hurst

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1979 Allis Chalmers 7000
5800 Hours

Posted By: rw
Date Posted: 26 Jun 2022 at 4:53pm

Do you have the thermostats installed with the correct part in the block?

Use your infrared to check below and then above the thermostat should be about the same. if cold above and hot below the stats are not opening or possibly in upside down.

I installed machine shop rebuilt a gas IH engine. The new water pump I bought was not drilled through correctly so it had no coolant circulation when thermostat was closed. We found this with a flashlight checking passages. It scored rear pistons with temp gauge not really that hot a two times in just a few hours running.

Use your infra red to make sure you have good circulation. Use your infrared to check top of rad vs bottom of rad. should drop at least 20 degrees from top tank to bottom tank. Top of radiator should be very close to same temp as engine. block on left should be very similar front to rear, head will be a little warmer than block. The reading from the infra red will be a few (5 to 10?) degrees cooler than coolant temp.

Posted By: rw
Date Posted: 26 Jun 2022 at 4:58pm

Surely the air flow is good if you had the radiator out and rodded. The infrared test for the difference in temp of the top and bottom rad tank will tell you if you transferring heat effectively.

Posted By: DrAllis
Date Posted: 26 Jun 2022 at 5:41pm

Sounds to me like you've purchased a problem child that has had issues long before you came on the scene. You shouldn't be using the tractor until : You can run the engine wide open throttle for 30 minutes to establish an operating temperature and that temperature should be 180 degrees !!! Verfied with a heat gun AND your new temp gauge !! Until you get to this point, you have no business using the tractor. Injection pump static timing may very well be at 18 degrees BTDC, but does it advance to 36 degrees BTDC when running??? It MUST do this. It cannot run cool if the timing isn't 36 degrees BTDC when running wide open. I'm having a hard time believing it runs an actual 200 degrees at an idle.

Posted By: JPG AUSTRALIA
Date Posted: 26 Jun 2022 at 6:46pm

Have you got thermostats in correct way?

Posted By: DrAllis
Date Posted: 26 Jun 2022 at 8:19pm

A couple of years ago, I had a Caterpillar C-9 engine (on a quarry lagoon pump) that had a severe overheating problem. Engines in this kind of use are known to get pond water dumped into the radiator over their service life instead of good quality coolant. Long story made short, I wound up replacing the engine with a reman. The coolant passages between the cylinder block and the head were plugged enough that coolant could not flow properly. It would get hot just running at wide open throttle over a period of 20 minutes or so and the heat gun was giving all sorts of stupid illogical readings that shouldn't have been.

Posted By: Ron(AB)
Date Posted: 26 Jun 2022 at 11:33pm

What about the oil cooler? It has antifreeze moving thru it. My 7050 had been almost plugged when I cleaned it last.

What if it is plugged too?

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405, 7000, 7050, 8050, 8070, L3, 2300 & 2600 disk

Posted By: Adam Stratton
Date Posted: 27 Jun 2022 at 10:12pm

Have you checked for good fuel flow to the pump? A clogged filter will make mine run hot. Also good clean air filters help, so might check there also...
I'm sure it's a dumb question, but how do you check to know what the timing is when the pump is running? -- edited to say I looked up diesel timing lights... Didn't know they existed. I've wondered about the differences in sound and apparent horsepower in some of my similar tractors and would be interesting to see how they compare...

Posted By: tbran
Date Posted: 29 Jun 2022 at 10:30pm

Quick check for coolant flow - fill the radiator to just under the filler neck - run the unit until you are sure the thermostats are open. Then, safely , watch the coolant as from an idle, have someone nail the throttle to high idle - the coolant level should suck down 2 to 3 inches then gradually come back up. IF nothing happens - you have a flow problem - IF it spews out - you probably have a head gasket issue. again don't get scalded... 90% of the over heating problems we have addressed were due to externally stopped up radiators or timing.

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When told "it's not the money,it's the principle", remember, it's always the money..