Allis G engine questions
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=41340
Printed Date: 28 Aug 2025 at 7:42am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: Allis G engine questions
Posted By: Richardmo
Subject: Allis G engine questions
Date Posted: 29 Nov 2011 at 11:31pm
|
I started working on G i bought awhile back the motor had a knock i was told after i bought the tractor at a auction.
so i pulled the head and nothing was hitting as there were enough clearnce on to the top of the pistons so went ahead put the head back on found out that one of the studs was strip out so i bought a helicoil and fix this.
when i went to start the tractor it had no oil pressure so i know how to prime the pump and i did seem okay with oil pressure running okay.
I let set for three days and went back to start the tractor no oil pressure and the knock was back with just cranking the tractor with starter.
Pulled the oil pan and the rods were standard crank pin was out of round .04
The good is the crank is standard.
my question is this enough for the oil drain out not have pressure or is something also wrong with the pump.
I do plan have the crank ground but woundering if when i tear this down if i should look for something wrong in the block that would cause to loose it prime.
Just a note someone supposely rebuilt this motor.
already found 2 bolts that were strip out one is a stud the other is one to hold the starter on.
Thanks for any info.
|
Replies:
Posted By: CTuckerNWIL
Date Posted: 29 Nov 2011 at 11:39pm
I hope that .04 is a mistake in your typing. If the rod journal is out of round 40 thousandths, the crank would have to be welded to get it close to standard size. If it is .004 inch I don't believe that would make it loose prime. I imagine you will get a few replies on what might cause the knock. I'm not familiar with the continental engines lube system so I won't be much help. ------------- http://www.ae-ta.com" rel="nofollow - http://www.ae-ta.com Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF |
Richardmo wrote:Posted By: Dave Richards (WV)
Date Posted: 30 Nov 2011 at 9:18am
|
Richard from your description of the recent rebuild, I'd start there. The installation of the oil pump is not rocket science, but has a lot of detail to adhere to. First check the pick-up tube and screen for blockages or leaks. Then the gaskets on the pump. The AC service manual for the G has a very good description of what you need to look for. Unfortunately, mine is at the farm. The ones on EBAY are on CD and not expensive. |
Posted By: Dick L
Date Posted: 30 Nov 2011 at 10:27am
This engine has a gear oil pump that is mounted on the back of the engine. Oil pressure is built on the flow of oil thru the bearings and the pressure relief valve located on the valve side of the engine behind a plug with a screwdriver slot.   |
Posted By: Richardmo
Date Posted: 30 Nov 2011 at 7:47pm
|
That is what i was meant .004 out of round.
I also thought that would not be enought to loose the prime the screen was clean.
will check the tube.
plan on removing the motor this weekend and see what i find about the pump and the and the relief valve.
Thanks for the information.
|
Posted By: Henry se/k!
Date Posted: 30 Nov 2011 at 8:31pm
| Working on 7045.Heads of both no 2 values broke off and pushed into head |
Posted By: Richardmo
Date Posted: 04 Dec 2011 at 7:26pm
|
I guess we know why it would only turn over and hit a hard spot.
Glad you made it home okay with the 7045.
Also here Henry with the 7045.
  Here is a update on the G here are picture of the lower Mains seems there is no hole in the bearing for the oil to go to crankshaft.
Also no hole in top half of the bearing.
  |
Posted By: CTuckerNWIL
Date Posted: 04 Dec 2011 at 9:22pm
|
Is there a hole in the insert that is in the cap? Somebody goofed here. ------------- http://www.ae-ta.com" rel="nofollow - http://www.ae-ta.com Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF |
Posted By: Richardmo
Date Posted: 04 Dec 2011 at 9:37pm
|
no hole in the top cap bearing just did not take a picture.
This is forth thing i have found.
1 head bolt strip and also a top starter bolts was strip out.
Starter was not shim right but had new brushes.
Also i notice they had patch the side of the block and sleve at least 2 cylinder so went ahead and put pressure on the block and head no leaks found though i better check with everything since i have been finding things done wrong.
|
Posted By: Fred in Pa
Date Posted: 05 Dec 2011 at 7:39am
| The cap gets a bearing with out hole ,the block gets bearing with a hole. Problely someone got a bearing set that was packaged wrong and they also did not know what they where doing ! |
Posted By: SteveMaskey(MO)
Date Posted: 05 Dec 2011 at 9:33am
| I bought one the same way Richard. When we tore it down previous owner had put it together with mains bearings that were not drilled. |
Posted By: Fred in Pa
Date Posted: 05 Dec 2011 at 11:10am
|
Just goes to show you ,not just any one can do it the RIGHT way.
|