Is there a mechanic in the house?????

[goldneagle]

I bought MC-2A diesel operated air compressor from Eglin AFB. I got it running ok but it looses oil pressure after about 20 minutes of running. When you first start it the oil pressure goes up to 55 PSI but it then slowly drops to 25 PSI and lower after running for about 20 minutes or so. The unit has a Deutz F1L208D air cooled diesel. It shares the oil with a rotary compressor. The oil is cooled by a OIL cooler radiator with a large electric fan.

I have already replaced the filters and has new 30 weight oil in her. Any ideas why the drop in oil pressure? It is also effecting the air pressure coming from the air compressor. As the oil pressure drops you get less and less air pressure produced! Any idea what might be causing this?

 

[doghead]

Any idea what the TM calls for, for oil?

 

[m-35tom]

30 wt is probably NOT the right oil to use. i would assume a multi vis oil since it is air cooled and the oil temp will be high. with straight 30 wt, the pressure you get makes some sense, high when cold and low when hot. this could be aggrevated by wear, but the most common problem with oil pressure dropping is oil thinning. if the correct oil does not cure it, i would check the oil pick up screen in the oil sump. it may be picking up dirt and clogging, this will sometimes drop back off when it is stopped for a short time, only to repeat next start up.

 

[goldneagle]

Any idea what the TM calls for, for oil?

I have had a request for a TM on this unit here on SS since I got the unit. No one has ever come across with one. If you know where I can get one i would appreciate it.

 

[goldneagle]

30 wt is probably NOT the right oil to use. i would assume a multi vis oil since it is air cooled and the oil temp will be high. with straight 30 wt, the pressure you get makes some sense, high when cold and low when hot. this could be aggrevated by wear, but the most common problem with oil pressure dropping is oil thinning. if the correct oil does not cure it, i would check the oil pick up screen in the oil sump. it may be picking up dirt and clogging, this will sometimes drop back off when it is stopped for a short time, only to repeat next start up.

I was told by some members here to use the straight 30 weight oil. The oil that came with the unit was clear and looked clean. Both oils give the same results. You would think the debris would have come out when I drained the oil during replacement...

 

[frodobaggins]

Since it shares oil with the compressor, maybe the seals inside the compressor are going bad, when it heats up, it gets past them and bam, pressure drop ? Dunno, just thinking out loud.

 

[glcaines]

Why not send an e-mail to Deutz and ask them what oil is proper? Or telephone them?

 

[maxim]

Deutz parts/dealer

MEMO-Omega MFG, Inc. - Home

 

[timntrucks]

sounds like seals in the compresser. do you have any leaks at all. how many hours on this unit

 

[goldneagle]

sounds like seals in the compresser. do you have any leaks at all. how many hours on this unit

No hour meter on this unit. I tried it with 30 Wt oil and it pumps too much pressure! It used to stabilize the air pressure below 200 PSI -now it keeps going over 220 PSI and I have to use the drain plug to lower the air pressure in the tank so it does not rupture! Looks like if I can use the proper oil viscosity in this unit it will function as designed. If I keep the pressure below 150 the engine runs faster and the oil pressure stays at around 23PSI.

I figure the first thing to do is use the proper oil and then see how the unit behaves. It may only need a tweak in the IP to let the engine have a little more fuel to increase power under load.

 

[timntrucks]

looks like your on the right tract

 

[MWMULES]

When you shut it down is the oil level still full? I am pretty sure it has a hydrovane style compressor which will use oil to help seal the vanes. If you drain the air tank is there a lot of oil in it? If so the vanes may be worn and and you are losing oil down stream. We used to use synthetic oil in them as regular oil can lead to carbon build up. Who is the compressor made by, Davey, IR?

 

[m-35tom]

you have something very seriously wrong with your compressor pressure control mech. the weight of the oil has something to do with how well it pumps, but nothing to do with how high the pressure goes. find out what is wrong with the pressure control first.

tom

 

[scooter01922]

At the very least there ought be a pressure relief valve of some sort that should trip, and i would guess its long before 200 PSI. But yeah, you must have something screwy in the gov department to have it keep building pressure with no end in sight.

 

[heavy_308]

you have something very seriously wrong with your compressor pressure control mech. the weight of the oil has something to do with how well it pumps, but nothing to do with how high the pressure goes. find out what is wrong with the pressure control first.

tom

X2....this is a must..
On the other hand, that Deutz will chug on forever. they never have run terribly high oil pressure, but have fairly high volume. The FL series is tough, and fairly fuel efficient, just keep your fins on the jugs and all spaces around the heads clear or debris.
I grew up on a hatchery, and we ran Deutz on everything. The tractor was the only one to ever need more than P.M. and that is because she was ran near WOT every day for nearly 30 years. I eventually replaced her bearings, rings and seals. and shimmed the injectors a tad. she still breathes today.

 

[m16ty]

I have had a request for a TM on this unit here on SS since I got the unit. No one has ever come across with one. If you know where I can get one i would appreciate it.

Have you checked here for a TM? https://www.logsa.army.mil/etms/online.htm

 

[hndrsonj]

Browse Technical Orders

Or go here and request a quote for the manual.

 

[JILY]

Here is a link to the manual
http://www.steelsoldiers.com/auxill...l-rand-mc-2a-air-compressor-2.html#post948816