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Topic: Puff of white (Read 576 times) previous topic - next topic

Puff of white

Ok, this has happened to me twice now and is super scary! I was on a long trip last year and when I parked to sleep that night I had a puff of white smoke come from under the dash near the steering wheel. It was odorless and I immediately opened the dash to find nothing.
A few months later I moved the bus a short distance and it happened again.

I have seen white smoke come out of a bulb before but not in the bus but was wondering if that could be the issue.

Any thoughts!!
2000 U320 36'
Build #5705

Re: Puff of white

Reply #1 –
Did this happen when you set the park brakes? If so it could be desiccant powder from a failed dryer. Other than that ????? as this is strange.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Puff of white

Reply #2 –
Quote from: Pamela & Mike –
Did this happen when you set the park brakes? If so it could be desiccant powder from a failed dryer. Other than that ????? as this is strange.

Mike

Easy to check-- open the wet tank drain valve.  Only clean dry air should come out.  Water, oil or worse-- white powder indicate a failed air dryer.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Puff of white

Reply #3 –
Well that brings up my question. Is a very small amount of dirty slightly oily material normal  or not. I haven't been concerned yet because I figured
 A. It's normally less than a thimble full and
 B. I figured oily would be better for the health of the tank, rust wise and all that ??
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Puff of white

Reply #4 –
Quote from: Bob & Sue –
Well that brings up my question. Is a very small amount of dirty slightly oily material normal  or not. I haven't been concerned yet because I figured
 A. It's normally less than a thimble full and
 B. I figured oily would be better for the health of the tank, rust wise and all that ??

Bob,

Dripping from where/ below what?
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Puff of white

Reply #5 –
Oh sorry. From the wet tank by the rear wheel.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Puff of white

Reply #6 –
It has been when I have parked both times so yes just after setting the parking brake. I have replaced the dryer to the rear so it is not original.
But even if the dryer had failed would that show up in the interior? Is there another dryer I should look for other then the rear one I replaced?


Quote from: Pamela & Mike –
Did this happen when you set the park brakes? If so it could be desiccant powder from a failed dryer. Other than that ????? as this is strange.

Mike
2000 U320 36'
Build #5705

Re: Puff of white

Reply #7 –
The powder can come from a previous failure and contaminate the system until cleaned.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Puff of white

Reply #8 –
Open the dash and set the brake while you watch. ?

Re: Puff of white

Reply #9 –
I took that advise and the puff of white does correspond to me setting the emergency brake.

Any recommendations on next steps to ensure my system is ok and not contaminated? I will order the Haled DQ6026 and replace the dryer. I saw on a different post that I should consider dropping the entire unit and rebuilding it. Is this standard protocol?

As always, thank you for your time!
2000 U320 36'
Build #5705

Re: Puff of white

Reply #10 –
Your system is comtaminated,a dryer rebuild will not uncontaminate it,it's a big job to get all the oil and powder out of the system,
where are you located,maybe one of us can help you.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Puff of white

Reply #11 –
Quote from: John44 –
Your system is comtaminated,a dryer rebuild will not uncontaminate it,it's a big job to get all the oil and powder out of the system,
where are you located,maybe one of us can help you.

To emphasize what John44 states - the entire air system is likely contaminated (potentially affecting leveling and coach braking) and needs to be cleaned.

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Air Dryer desiccant contamination creates symptoms of air leak (split from...

Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Puff of white

Reply #12 –
I am in Kansas City.

I will drain the wet tank tomorrow and see what I find.
2000 U320 36'
Build #5705
 

Re: Puff of white

Reply #13 –
Is the white smoke water or dust? I'd suggest draining the front tanks as well as the wet tank. Hopefully it's just some moisture coming out of the parking brake valve when you set the brakes.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246