talgutbir Report post Posted August 10, 2015 Hi All, I noticed on my engine today that a hose clamp was loose and the rubber hose was off the nipple. This is the hose that connects between the intake manifold and air compressor. I have attached a picture to show the hose. In the Cummins parts list this section as " Cpr Air Inlet Arrangement". Can anyone tells me what it does and what are the implications of driving with the top of the hose not fully connected to the intake manifold? Thanks! Share this post Link to post Share on other sites
huffypuff Report post Posted August 10, 2015 It is what the Cummins parts list says. It is the air inlet for the air to be compressed by the air compressor. Hopefully clean air as it should be filter by the big engine air filter. With that hose off the air compressor would be sucking in dirty air. Share this post Link to post Share on other sites
talgutbir Report post Posted August 10, 2015 I guess just monitor the compressor performance and hope for the best? Share this post Link to post Share on other sites
wolfe10 Report post Posted August 10, 2015 Guess I am confused. If that is the supply hose for the air compressor it is taking clean, PRESSURIZED air (turbo boost) from the intake manifold. If that hose was off, I can't see how you would be able to build boost. In other words the engine would have VERY little power. Share this post Link to post Share on other sites
dickandlois Report post Posted August 10, 2015 talgutbir, As Ray and Brett mentioned. you should have a loss of compressed air recovery and NO boost!Did you reconnect the hose and tighten the clamp?The loss of boost will decrease engine performance, plus drawing in unfiltered air into the compressor will cause damage. Also, the dirt that gets into the air compressor will migrate into the engine oil supply and cause wear inside the engine also !!!!! The price of a new hose is FAR cheaper then replacing one compressor and a lot lees then needing engine work !!!! To get the proper hose you will need the engine serial number-you can get it from the chassis manufacture if you do not have it on file.You might want to consider an oil and filter change if you do not know how long the hose has been loose as a extra measure.An oil test could also be performed to evaluate if any other damage has been caused.Rich. Share this post Link to post Share on other sites
wolfe10 Report post Posted August 10, 2015 Yes, if driven with that hose off, there could be serious issues. But, I am still trying to picture how you could drive with no boost-- just can't do it. So, let me ask you-- did you have a SERIOUS drop in power? If so, for how long? That will give you an indication of whether you need to change oil immediately, etc. Share this post Link to post Share on other sites
talgutbir Report post Posted August 10, 2015 I am not sure how long the hose was off. When I say "off" it was against the nipple, not hanging completely off in the air. I had/have boost (about 5psi on level road and going up to the mid-high 20's up hill) and nothing seems to be wrong with performance of either the engine or compressor. I did reconnect the hose and tighten the clamp after finding this problem. I changed the oil 2600 miles (May 2015)ago. I guess I can change it again. Share this post Link to post Share on other sites
wolfe10 Report post Posted August 10, 2015 I can't see how you could generate 20 PSI of boost with the hose off. Easy to test. Warm up the engine. Turn it off. Pull the hose off and drive one mile or less, going to WOT at higher RPM. As long as full air pressure was built before turning off the engine, unlikely the compressor will even run at all. See what kind of boost you get. Again, I am just speculating on this (presence of boost= no problem. Share this post Link to post Share on other sites
talgutbir Report post Posted August 10, 2015 Wolfe10, as I said, the hose wasn't completely off, but just pressed against the end of the nipple. I talked to Cummins tech support and was told that the boost would not be affected and the chances of getting dirt into the engine from the intake are very very slim. They suggested to take the air hose from the compressor to the air tank off, run the engine and put a clean rug on the hose to see if it blows air with oil. If its not, just forget about this issue and monitor oil consumption over time. Share this post Link to post Share on other sites
hermanmullins Report post Posted August 10, 2015 talgutbir, I'm not trying to be a smart alec, but put the hose back on tighten the clamp and let us know how your engine preforms then. I hope that you have not pulled in too much dirt. Herman Share this post Link to post Share on other sites
DaveAtherton Report post Posted August 13, 2015 Gentleman, I do not want to be a nay sayer but lets put the cart after the horse. the subject is about loose hose and talgutbir said it the way it is. put the hose on and run it. The question about turbo being bought into this mix is not correct and will not affect turbo charger in any way. ISL Cummins has what is called a variable pitch turbo, which means a set amount of exhaust will go back into the intake of engine via is a sliding ring and a defuser plate that has a electric motor actuator. the boost pressure in the intake tells ECM more boost than the electric actuator moves the into the defuser.this one area that will give problems because of carbon buildup and will make actuator ring sticky. The ISL also has a cleaning mode at startup for the variable pitch turbo that makes a loud clicking noise while going cleaning mode. Dave Atherton Retired Cat Mechanic Share this post Link to post Share on other sites
talgutbir Report post Posted August 15, 2015 DaveAtherton, thanks for your reply! I think that the hose was barely off so no dust was getting into the compressor line. Next service appointment I will have them run a cleaning solution into the compressor just to be on the safe side. Share this post Link to post Share on other sites
