Farm Equipment - Rebuilt 426 with a weird noise.

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Rebuilt 426 with a weird noise.

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=159909
Printed Date: 19 Nov 2025 at 1:13pm
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Topic: Rebuilt 426 with a weird noise.

Posted By: AC 426 power
Subject: Rebuilt 426 with a weird noise.
Date Posted: 11 Apr 2019 at 6:01pm

Got my 7060 back together after rebuilding the engine, runs good, oil pressure is at 25 psi at idle, after a couple of hours of hard hard chisel plowing running John Deere break in oil, no blue smoke, starts better since I advanced the pump to 19 degrees, no noticeable blow by, but I'm hearing a whooshing sound or like air escaping somewhere when running at high RPM, primarily with the cab door and windows shut, doesn't seem to really lack power while pulling a 9 shank, remanufactured injectors, brand new turbo, all my connections look tight going from the air filter to the turbo, new intercooler boot, all new intercooler gaskets etc. Just an aggravating whooshing sound, any thoughts?

Replies:

Posted By: oldways
Date Posted: 11 Apr 2019 at 6:04pm

Air in hydraulic a system ?

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1 Corinthians 1:18 1969-190xt-III. 1966 190xt gas. 1966 190xt Cab. 1948-G. 1937-WC unstyled. 1950-B. 1951-CA. 1966-D17-IV

Posted By: Lynn Marshall
Date Posted: 11 Apr 2019 at 6:38pm

Intercooler gasket problem??

Posted By: AC 426 power
Date Posted: 11 Apr 2019 at 7:17pm

Lynn Marshall wrote:

Intercooler gasket problem??

That's kinda what I'm leaning towards, but it is new and it seemed to go on right

Posted By: AC 426 power
Date Posted: 11 Apr 2019 at 7:19pm

oldways wrote:

Air in hydraulic a system ?

seems more like it's coming from the engine

Posted By: MACK
Date Posted: 11 Apr 2019 at 9:30pm

Have saw them blow at back of intercooler. Have been using some gasket sealer on them. MACK

Posted By: ryan(IN)
Date Posted: 11 Apr 2019 at 9:33pm

Even if you think the rubber hose on the cross over seems tight check it. We had one come loose and make the noise you are describing.

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ryan
1984 8070 FWA,1979 7060,1975 7040,1971 190,1960 D-17D,1957 D-14, 196? D-19G, 1975 5040,1971? 160,1994 R62

Posted By: Ed (Ont)
Date Posted: 12 Apr 2019 at 5:02pm

Pressurize the air to air and as much of the hosing as you can. About 20 psi. You will find the leak if there is one. Sure sounds like it.

Posted By: Boss Man
Date Posted: 14 Apr 2019 at 8:18am

Know a guy that had a JD engine rebuilt at the dealer. Had great power but had a noise under load. Took a while but we found the intake wasn't completely tight. Had to put shorter bolts in in a couple of places

Posted By: AC 426 power
Date Posted: 14 Apr 2019 at 10:15am

Ed (Ont) wrote:

Pressurize the air to air and as much of the hosing as you can. About 20 psi. You will find the leak if there is one. Sure sounds like it.

Where would be a good place to hook into it?

Posted By: DrAllis
Date Posted: 14 Apr 2019 at 10:30am

There are only so many places it can be leaking. The turbo hose to crossover pipe. The crossover pipe gasket to the intercooler. The 4-bolt cover on top of the intercooler. The intercooler to cylinder head gasket. That's it. This of course assumes all the plugs ( four) are in the intercooler body. This also assumes you don't have an exhaust leak, which you should see the soot from. It would take me less than an hour to drain the coolant in a clean 5 gallon pail and remove all the intercooler bolts and see what is going on. I always glue (3M brand 8001 yellow) the intercooler gasket to the intercooler and a thin layer of any RTV from the gasket to the cylinder head and recheck the bolt torque (engine COLD) after it has run a couple of days. You did glue the intercooler gasket to something, right ??

Posted By: Lynn Marshall
Date Posted: 14 Apr 2019 at 10:52am

You could hook up some air pressure to the ether port,but with open valves, I don't think that it will tell you much. The intercooler to the head gasket is most likely the problem if it is an intake leak.

Posted By: injpumpEd
Date Posted: 14 Apr 2019 at 11:15am

It's a lot of work, but to pressure check the intake tract, you can take the rocker assembly off, and put a plate in place of the crossover tube. My bet is either blown intake gasket, or a small plug left out on intake somewhere.

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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!

Posted By: AC 426 power
Date Posted: 14 Apr 2019 at 1:29pm

DrAllis wrote:

There are only so many places it can be leaking. The turbo hose to crossover pipe. The crossover pipe gasket to the intercooler. The 4-bolt cover on top of the intercooler. The intercooler to cylinder head gasket. That's it. This of course assumes all the plugs ( four) are in the intercooler body. This also assumes you don't have an exhaust leak, which you should see the soot from. It would take me less than an hour to drain the coolant in a clean 5 gallon pail and remove all the intercooler bolts and see what is going on. I always glue (3M brand 8001 yellow) the intercooler gasket to the intercooler and a thin layer of any RTV from the gasket to the cylinder head and recheck the bolt torque (engine COLD) after it has run a couple of days. You did glue the intercooler gasket to something, right ??

I did use a bit of super glue on the gasket to mate it to the intercooler so it would stay in place while I installed, no rtv though. All I can see is 3 plugs right in front, 2 small and one big one.