How does it work, Compressor to turbo connection

[tednruthy]

Hey, I am broke down and my ISL9 with 12K miles on it won't climb a hill. Shop says a hose clamp is missing on a hose on the compressor. Diagnosed at 1PM part to arrive at 4PM shop closes at 5PM. Have to wait until tomorrow now. I am asking for a techie to explain to me the relationship of the air compressor to the turbo as the error was low Boost pressure. I thought the compressor was just for producing air for the brakes and suspension? I had only about 13 boost max on a climb, Low boost error and check engine light. Spent 28 hours with changing fuel filters and air filter and inspecting CAC air path for bad hoses or loose clamps and getting towed after still failing. Now waiting for tomorrow.

Ted

[Cat320]

Have you checked for a plain old turbo leak? Maybe around a hose or fitting? With this type leak, you'll have normal RPM, but no power.

[PDR John]

Wrong compressor. I just went through this.

What happened is you've blown a turbo hose off. The turbo is a compressor.

The is a tube the runs from the turbo to the inter cooler, inter cooler and tube are connected by a hose. That hose has blown off, no turbo boost.

Freightliner just did a full replacement of all my hoses and tubes, under warranty.

I will post a pic in a couple mins.

[palehorse89]

The air compressor take clean/filtered air from the turbo fresh air piping........would not affect the engine........now if you have a leak on the compressor side or the turbo, going to the charge air cooler then to the intake manifold somewhere........you would not build boost........must be a pretty good leak/piping separation.......better to have this, than on the suction side, the turbo would be ingesting dirt/dust. Should be a simple/easy fix, and should not take to long.......if this in deed what is worng. Good Luck, and try and enjoy the evening.

[PDR John]

The clamp on mine that broke.



The new tube and hose



Plus new mounting bracket



Old weak hoses were blue in color and the tube was welded together.

The old set up.

[D Lindy]

Having a leak in the fresh air hose to the Air Compressor for the MH's brake system will cause a loss of power. What happens is that the turbo boost is leaking out the fresh air hose going to the Air Compressor thus no boost to the motor, and loss of power. Had this happen in a truck I drove and the mechanic would not believe that I had a loss of power till he went on a test drive with me and had his computer hooked up and saw the loss of boost. The found that the fresh air hose to the Air Compressor had a rip in it.

[palehorse89]

Originally Posted by D Lindy

Having a leak in the fresh air hose to the Air Compressor for the MH's brake system will cause a loss of power. What happens is that the turbo boost is leaking out the fresh air hose going to the Air Compressor thus no boost to the motor, and loss of power. Had this happen in a truck I drove and the mechanic would not believe that I had a loss of power till he went on a test drive with me and had his computer hooked up and saw the loss of boost. The found that the fresh air hose to the Air Compressor had a rip in it.

I don't agree, this is on the "suction" side of the turbo compressor(Air compressor filtered air), and if the hose going to the air compressor was off/cracked, the air compressor would be sucking in un-filtered air, and the turbo compressor would also be sucking in un-filtered air, not affecting the compressors job, other than sucking in un-filtered air.............To loose turbo boost , the leak would have to on the exhaust side of the turbo compressor.
John's picture's above, are of the exhaust side of the turbo's compressor, heading to the CAC.

[2 Stroker]

Same thing happened to me on my 06 Ford PSD. I changed the boots and did not get it tight enough and came off under boost on the hot side of the turbo, sounded like a boom went off, O power O boost Lucky I found the clamp and had tools to fix.
2 stroker

[PDR John]

I got lucky to find a clamp in Nowhereville IN to replace the broken one. had to lay on my KarGuard to stay out of the snow while changing it. It was on the cold side of the CAC, pinched by the wheel well.

The hot side blew off twice on me, both times I was able to put it back on.

Now with all the new parts I see 35 psi boost, 2 lbs more then with the old parts. Must of always leaked.

[tednruthy]

Looks to me like you are the closest of the 7 posts so far. I was just at the repair center and saw the hose that was blown off with the missing clamp. I do believe I know the difference between the compressor used for braking and suspension and the Turbo. The hose is off the compressor on the curb side of the engine well below the much larger CAC hoses that are on BOTH sides of the ISL engine. Street side hose from Turbo to CAC and curb side from CAC to engine intake I believe. These turbo hoses are HIGH up on the engine. The hose that is off is LOW and on the curb side and on the air compressor. Only about 2 inches in diameter. The clamp is gone but looks like there is about 5/8 inches where there is no dust but on this area also no sign of a tight clamp compressing the hose? Still waiting for hose install and test drive to be completed in the AM. Still waiting to award the prize for whoever can tell me what this compressor air has to do with the turbo boost.

Originally Posted by D Lindy

Having a leak in the fresh air hose to the Air Compressor for the MH's brake system will cause a loss of power. What happens is that the turbo boost is leaking out the fresh air hose going to the Air Compressor thus no boost to the motor, and loss of power. Had this happen in a truck I drove and the mechanic would not believe that I had a loss of power till he went on a test drive with me and had his computer hooked up and saw the loss of boost. The found that the fresh air hose to the Air Compressor had a rip in it.

[twinboat]

Guys, the hot side of the turbocharger has an exhaust pipe hooked to it. Most use a V type band clamp.

[palehorse89]

Originally Posted by 2 Stroker

Same thing happened to me on my 06 Ford PSD. I changed the boots and did not get it tight enough and came off under boost on the hot side of the turbo, sounded like a boom went off, O power O boost Lucky I found the clamp and had tools to fix.
2 stroker

Both sides of a turbo are hot per say(Red arrows in photo above) and yes, the exhaust is hotter, but the compressor side is nothing one would want to lay their hand on..........so.......what is the "Hot Side" of a turbo?
Holset's Guide on How a Turbo Works. Compressor side could see 400 deg. As to why it next enters the Charge air cooler(Inter cooler).

[twinboat]

The hot side is the cast steel exhaust turbine that get over 1000 degrees. They glow in the dark, under load.

The cold, compressor side, is made of aluminum and has hoses on it.

[palehorse89]

Originally Posted by tednruthy

Looks to me like you are the closest of the 7 posts so far. I was just at the repair center and saw the hose that was blown off with the missing clamp. I do believe I know the difference between the compressor used for braking and suspension and the Turbo. The hose is off the compressor on the curb side of the engine well below the much larger CAC hoses that are on BOTH sides of the ISL engine. Street side hose from Turbo to CAC and curb side from CAC to engine intake I believe. These turbo hoses are HIGH up on the engine. The hose that is off is LOW and on the curb side and on the air compressor. Only about 2 inches in diameter. The clamp is gone but looks like there is about 5/8 inches where there is no dust but on this area also no sign of a tight clamp compressing the hose? Still waiting for hose install and test drive to be completed in the AM. Still waiting to award the prize for whoever can tell me what this compressor air has to do with the turbo boost.

Answer: One word: Nothing