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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Scott & Heather on November 08, 2016, 08:22:39 AM

Title: Boost suddenly returns?
Post by: Scott & Heather on November 08, 2016, 08:22:39 AM
Up until yesterday if I tried to push the coach 70 mph in warm or hot weather it would run a little warm. I always had quite a bit of black smoke on acceleration mostly because we've turned up the horse power ratings on my 8v92 to nearly 500 hp. So I expected this. I have had a slightly low boost issue for a while that I have not chased down yet. But it did appear to be at least in part a restriction of my air intake because my filter minder maxed out. Cliff gave me the info for upgrading my filter and housing which I was planning on dealing with next summer. Yesterday for the some reason my boost came back, and I can hear the turbo whistling really nicely all the sudden, and the bus will not overheat even though I pushed it 75 to 80 mph yesterday through hills for hours in 70° heat and it never once got warm what gives? I tried everything I could do to get it hot yesterday, even lugged it through the hills at 55mph in 4th gear. I am loving this, she has even more power and doesn't get hot...but why all of the sudden? I did remove my engine doors two days ago because I was majorly fighting heat during a strong headwind outside of Palm Springs and just thought I'd try running without the lower engine doors. But I don't believe for a moment that made any difference...certainly not in the boost department.


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Title: Re: Boost suddenly returns?
Post by: lostagain on November 08, 2016, 08:28:58 AM
Check to make sure the intake, up stream of the air filter, like between the filter and the turbo, hasn't broke open. That would result in no more restriction from the filter, and sucking in dust and crap. That would give you more air, and more boost.

JC
Title: Re: Boost suddenly returns?
Post by: eagle19952 on November 08, 2016, 08:41:54 AM
cooler heavier air at lower altitude always makes a difference..death valley..drive from Badwater Basin to any where and you will discern the difference, quite memorable actually :)
Title: Re: Boost suddenly returns?
Post by: luvrbus on November 08, 2016, 08:50:49 AM
You could have had a lot of build up in the muffler that turn loose,colder air does increase boost and power though
Title: Re: Boost suddenly returns?
Post by: bevans6 on November 08, 2016, 08:52:40 AM
Clifford beat me to it, I was about to post that you could have had a restriction in the muffler that got cleared...  Need to be quicker on the draw!
Title: Re: Boost suddenly returns?
Post by: stanton on November 08, 2016, 10:14:53 AM
Your shutters were closed , or you took the winter front off?
Title: Re: Boost suddenly returns?
Post by: TomC on November 08, 2016, 10:56:50 AM
As Clifford said, make sure your air intake between the air cleaner and turbo is tight and attached. Sean and Louise had that come apart and went through their 8V-92TA in short order for an expensive rebuild. Also, inspect the air cleaner element to make sure it hasn't collapsed or torn. Good Luck, TomC
Title: Re: Boost suddenly returns?
Post by: Scott & Heather on November 08, 2016, 08:48:56 PM
Inspected the entire intake system and all boots. All is well. As I went up in elevation the past two days, she went back to her former self somewhat. So you're saying my low altitude driving a couple days ago made all that difference? Wow.
Title: Re: Boost suddenly returns?
Post by: Geoff on November 09, 2016, 05:44:55 PM
A turbo whistling indicates a leaky turbo clamp.  This certainty will affect your turbo boost.

--Geoff
Title: Re: Boost suddenly returns?
Post by: eagle19952 on November 09, 2016, 06:51:10 PM
spraying ether around your intake piping connections and clamps etc. will id leaks quickly.....


uhm... I guess i've heard a few thousand leaky turbos....

https://youtu.be/SU-jhgBUPU8?t=1m36s (https://youtu.be/SU-jhgBUPU8?t=1m36s)


https://youtu.be/7MiFOLw8dcU?t=19s (https://youtu.be/7MiFOLw8dcU?t=19s)


Title: Re: Boost suddenly returns?
Post by: TomC on November 11, 2016, 08:03:47 AM
You'll hear turbo whistle with straight pipes (no muffler)
Title: Re: Boost suddenly returns?
Post by: Oonrahnjay on November 11, 2016, 08:22:52 AM
    What's the status, Scott?  Has the "power boost" stayed with you?  Have you found any troubling conditions or indications?  I hope all is well.

    I hate "unexplained intermittent problems".  Some people say that they build character.  I grew up dating North Carolina girls, I worked for British companies for over 20 years, and I useta be engaged to a red-headed woman -- believe me, I got all the "character" I can use.  I hate "unexplained intermittent problems".
Title: Re: Boost suddenly returns?
Post by: Jim Eh. on November 11, 2016, 05:56:51 PM
 :D
Title: Boost suddenly returns?
Post by: Scott & Heather on November 12, 2016, 10:31:19 PM
Lol. I am married to the lowest maintenance girl on the planet. Can't relate John. Yes I still have the boost an turbo whistle. I have some soot at the exhaust side of the turbo so I'm sorting that out this week. Been performing in Portland this weekend without a single moment to get dirty. (https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fuploads.tapatalk-cdn.com%2F20161113%2Fc71ea3c80d4f50fd1d67e3e02941b6be.jpg&hash=ea6cfa30704ac0f583943d51dd0909cdad6af2ab)(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fuploads.tapatalk-cdn.com%2F20161113%2F4ce7492d014ebf38cf79b3fb49a40766.jpg&hash=ba810644698a2ee00115125fc8f75634c38448d2)


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