Farm Equipment - 7080 first engine startup

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7080 first engine startup

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=181995
Printed Date: 28 Aug 2025 at 3:52pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: 7080 first engine startup

Posted By: YZfarms1
Subject: 7080 first engine startup
Date Posted: 24 Jul 2021 at 9:02pm

Good evening forum members. This is a continuation of my original post from last winter....price of a crappy 7080... I finally started the engine today for the first time. I had to purchase a new starter, and have the injection pump rebuilt, among other more minor issues. It started easily, and runs smooth, but makes a loud popping sound that is consistent with engine speed. I would not call it a ticking sound. Nor would I call it a banging sound either. Popping is the correct choice.

Initial advice from more knowledgeable people is that it is a stuck valve. I was instructed to remove the 426 inline six valve cover and identify the culprit. Once identified, do I just keep lubing the stuck valve while spinning it until it moves freely ?

Or is there another possibility ? By the way, the 426 is not the 3750 version that should be in the 7080. It is actually a 3500 version. Someone obviously changed it years ago.

I will continue to seek the forums advice on issues as they arise during my tractor restoration project. This is my first time. Be gentle !

Replies:

Posted By: MACK
Date Posted: 24 Jul 2021 at 9:13pm

Sounds like a push rod off. Did you turn the engine over several times before adjusting valve lash? You did adjust valves?

Does the popping sound come from intake? MACK

Posted By: rw
Date Posted: 25 Jul 2021 at 5:35am

I had a noise and it turned out an injector was loose in the head. Check the hold down bolts on them.

Posted By: injpumpEd
Date Posted: 27 Jul 2021 at 8:13am

Turns out that was the issue here too. Glad it's something simple!

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210 "too hot to farm" puller, part of the "insane pumpkin posse". Owner of Guenther Heritage Diesel, specializing in fuel injection systems on heritage era tractors. stock rebuilds to all out pullers!