Oil Leak and pressure question.

[engineer233]

I have a small oil leak to say the least. I have a M923 with a NHC-250. This is my first 5 ton and am going through a learning curve with it. On the way home when I picked it up it started leaking 1 gal every 50 or so miles. Got the truck home and pressure washed the engine , later started it and it run for at least an hour and nothing. Took a 3 mile drive and raised the hood and here we go again. The oil is slinging off the fan pulley. The only logical reason for this I can tell is it may be coming from the accessory drive pulley ,but can't really tell as the fan has blown it all over again. What else can I check or what common problems could this be ? My truck runs 30psi on the oil at idle and 90-100 at highway speed. This is of course at operating temps. What should this be or is this normal ?

 

[ClintA]

That sounds like a bad leak. Mine leaks a little at the oil pan but it does not get worse when it is running. Mine runs around 60 pulling a load, It never gets on the hiway so I do not know at high speeds. I dont know what to tell you.

 

[Buttweet]

Engineer233, whats the latest on your 923 oil leak? Just discovered my 923 is seeping oil from behind the pulley just to the left of the fan. Think it the same location as your leak. Drips pretty fast after short trips. I don`t see an easy access to the seal. The pulley slings the oil everywhere. Thought I had a good engine, now this. Has anyone ever pulled off this pulley and if so can you get to the seal? Any advice would be appreciated.
Thanks

 

[73m819]

Pull the accessory drive pulley, pull the seal in the gear cover and replace, check the seal ware surface on the pulley snout, if grooved, use a speedy sleeve (if using a sleeve, fill the grove in with harding eproxy)

 

[Buttweet]

Thanks, You make it sound easy. I can imagine I`ll need some special pullers for pulling the seal out, like do I drill holes in the seal to jerk it out or is this procedure explained in one of the TM`s. Just glad it is doable w/o removing the gearcover. Thanks

 

[Barron]

This is probably going to be an on-going issue as these 900 series start coming home from sitting so long.

Might be a good idea to post the seal number and the speedy sleeve info as soon as someone gets further into it.

I looked at a bunch of M936's online from Camp Shelby, and they are all looking pretty weathered.

 

[Buttweet]

I found what looks like the accessory drive area on front of the engine in JATONKA`s TM
TM9-2320-272-24P-1, Fig 44 page 44 thru 44-3. Only seal listed is pn 211255, cage 15434.
Would like to hear from someone who has actually performed this procedure.
Thanks

 

[Hoefler]

Shortly after I recovered my M923 I had a leak at the bell housing. Kept an eye on it-was just drips. After about 300 miles on her, the leaked eventually stopped. The one concern I have is my oil pressure-seems high at about 80 PSIG when running at highway speeds. Everything seems ok but pressure-to me it seems high. Any others out there that could report oil pressures.

 

[engineer233]

My truck when cold pegs out at 120 psi. When hot at highway speed it does around 80.

 

[Hoefler]

OK-sounds just like mine. Seems high to me, but have read of another members truck at 80 plus. Must be ok.
Pete

 

[ARYankee]

My truck when cold pegs out at 120 psi. When hot at highway speed it does around 80.

I had the same concern because mine does the same.