Construction and other equipment - HD 7 G engine problems

Print Page | Close Window

HD 7 G engine problems

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Construction and other equipment
Forum Description: everything else with orange (or yellow) paint
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=36120
Printed Date: 25 Jun 2025 at 6:20pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: HD 7 G engine problems

Posted By: Chitwoodshan
Subject: HD 7 G engine problems
Date Posted: 25 Aug 2011 at 2:30pm

The engine started loosing oil pressure after in ran for 10-15 mins. The machine sat for about a year and I had to move it. Put in new batteries and machine cranked with starting fluid ( not much ) . I lifted the bucket and it chattered so I throttled down and machine went dead. Added 5 gals of Hyd. fluid and went to restart but all engine would do was bump, fan would move about 1 1/2 per starter bump. How hard is engine to rebuild? Could this be a spun main bearing? or any Ideas. I've rebuilt plenty of gas engines but no diesels.

Replies:

Posted By: michale34
Date Posted: 25 Aug 2011 at 3:55pm

there not that hard to rebuild its just parts are a little expensive here is a phone number to west rock company that deal with ac parts in little rock ar 501-228-0330- mr jones has 7been an ac man for years since i was a kid . someone was selling surplus 7000 engines.

Posted By: Chitwoodshan
Date Posted: 26 Aug 2011 at 3:39pm

Thanks I'll check with him.

Posted By: gemdozer
Date Posted: 26 Aug 2011 at 3:46pm

I dismantled some HD7G for parts if I can help with used parts

Posted By: Kcgrain
Date Posted: 26 Aug 2011 at 4:13pm

I thought a 7G has a 6cylinder 426 in it an overhaul kit is like 1200 bucks, if you need a 7000 series engine I have 2 new ones.

Posted By: Chitwoodshan
Date Posted: 27 Aug 2011 at 3:15pm

I've got to figure out which engine I have. I know its a 6 cyl. with turbo but thats all I know. What's the best way to Identify which engine I have?

Posted By: DrAllis
Date Posted: 27 Aug 2011 at 8:02pm

FIND THE "TAG" RIVETED TO THE LEFT SIDE ?? OF THE ENGINE....I THINK YOU HAVE A 3500 SERIES ENGINE.

Posted By: gemdozer
Date Posted: 28 Aug 2011 at 5:21am

If you have a motor 6 cylinder your machine should be a HD7GB WITH 3500 motor

Posted By: Chitwoodshan
Date Posted: 30 Aug 2011 at 12:10pm

Thanks guys ! I'll look today. My wife is after me to sell it for scrap but I couldn't do it. The machine worked great until engine failure. Hyd. , undercarrage, brakes , 4 in 1 bucket.