What is normal turbo boost on Series 60 11.1L?

[belfert]

I have a 1995 Series 60 11.1L in my bus.  What PSI should I be seeing on my turbo boost?

I don't know that I have seen more than 10 PSI via VMSpc.  I see where Richard just repaired the Series 60 in his Newell and is seeing boost of 30+ PSI.  I'm wondering if my turbo is going bad or maybe the 11.1L just develops less boost?

[buswarrior]

like a religion, check all clamps and connections for tight fit. The smallest leak on the pressure side takes it all away.

happy coaching!
buswarrior

[RichardEntrekin]

Brian,

I run about 6 to 8 lbs cruising at 65 and 1500 rpm.  Climbing a pretty good hill and staying in the throttle will produce 25 to 28. I was hammering the throttle on a very tough hill just to see how much boost it would build when I topped 30.

All of this comes from the VMSPc also, not the guage. Although the guage and the VMSPc track pretty closely on this one. Which is not the case for my water temp though.

Mine is a 12.7 and DDEC III, so I know we are not talking exact comparison.

[belfert]

I don't have a boost gauge on my dash.  The water temp from my VMSpc tracks pretty much right on with my dash gauge.  I usually run right at 195F in the summer, but I have been at 190F pretty much the whole trip.

I will have to watch my boost closer on a big hill.  Maybe it is getting up higher than I think at those points.  I'm still wondering what I should be seeing as normal.  Certain things on an 11.1L are different from later 12.7L models.

[rv_safetyman]

Brian, I don't know how much difference there is between a 11.1 and 12.7, but most modern 4-stroke engines rely heavily on turbo boost.  I would think you should have at least 20 psi with a clean air filter and a big hill with full throttle and relatively high RPM.

When I was having issues with the mis-match of the ECM/manifold pressure sensor on my new engine, I only got about 12 PSI max on a big hill and the power was terrible.  I would guess that you are seeing part throttle boost.

The VMSpc has a "percent load" "gauge" and that will tell you when you are really pushing your engine.  When it is 100%, you should have at least 20 psi.  If you are using the "dash" screen I sent you, it is the gauge next to the time.

Jim

[belfert]

Update: At 100% engine load I am seeing a max of 18 PSI.  Heading down the road normally I see around 5 PSI.  I am going to see what it does on Monteagle this morning.

I might pull the intercooler in the spring and have it checked for leaks.  I can get the intercooler out in about an hour.  I doubt the local radiator place charges much to test an intercooler.  I looked over the clamps on the boots and they all seemed tight.

[rv_safetyman]

Brian, that sounds a bit better, but still low.  Sounds like you will have the chance to test it on a big hill today.  That will be the real test.

In order to build full boost, you need full air and fuel and no significant leaks in the charge air system.  So, that means you need to make sure your fuel filters and air filter are in reasonably good condition.

When I had my issues with lack of boost when I put the second Series 60 in, I made two inserts for the charge air plumbing so that I could statically test the complete system.  Both were made with 4 inch tubing - one capped off and one with an air fitting.  I unhooked the flexible hose from the turbo and put the capped end in the tube.  I then unhooked the the hose from the intake manifold and put the tube with the air fitting in that hose.  Then, with a pressure regulator set at 30 PSI, I pressurized the system.  I then sprayed all of the hose connections and the charge air cooler.  I found a few small leaks in the hose connections.  I did not find anything that would have caused my horrible loss of boost, so that pointed me in other directions (turned out to be a boost pressure sensor/ECM incompatibility).

If you want to play with a static test, I will be glad to send you my hose adapters.  If I do, please do not tell folks how crude my TIG welding is (still learning)

Jim

[luvrbus]

To answer the original question Brian the 11.1  350 hp with 55 injectors and standard turbo the max is around 19.2 if you don't know if the engine has been upgraded to the new style piston ,head gasket and bolts keep it there or it will be Coachnet and crying time

good luck

[belfert]

If Clifford is right I am seeing the correct boost for my engine.  Maybe just a tiny loss.

Even on Monteagle I only saw 18 PSI max.  Monteagle didn't seem as bad on the way back as on the way there.  East and west do diverge going around the hill/mountain.  East may have seemed worse because traffic was heavy and I was stuck behind a car going 30 MPH.  I was able to maintain 55 MPH going back west.

[Busted Knuckle]

If Clifford is right I am seeing the correct boost for my engine.  Maybe just a tiny loss.

Even on Monteagle I only saw 18 PSI max.  Monteagle didn't seem as bad on the way back as on the way there.  East and west do diverge going around the hill/mountain.  East may have seemed worse because traffic was heavy and I was stuck behind a car going 30 MPH.  I was able to maintain 55 MPH going back west.

Brian it's the same either way. But the grade is not quite as steep going up west bound! Also having the extra lane on the west bound side helps keep it from getting congested as soon as the east side does!
FWIW I'd trust Clifford and leave it be!
  BK 

[niles500]

"If Clifford is right" - blasphemy I tell you 

[Busted Knuckle]

"If Clifford is right" - blasphemy I tell you 

  BK 

[belfert]

FWIW I'd trust Clifford and leave it be!

It sounds like I am getting the correct boost for an 11.1L so I'm not worrying about it.  I do have to remove the intercooler anyhow to fix the water pump.  Joel at the Choo-Choo Express garage confirmed my water pump oring is leaking oil.  It is going to be a major pain to pull the water pump with the radiator in place.