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Topic: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME (Read 1033 times) previous topic - next topic

Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

We are having a problem on a 6BTA 5.9 Cummins with bubbles and coolant going into surge tank to the point of overflow. Also engine will start to overheat after a while.

We have changed the water pump. The thermostat. Had the radiator remove and cleaned and all new treated coolant changed. The head was magnafluxed and the head gasket changed. Changed the radiator cap. Checked the fan hi/low operations.Checked for trapped air, and had the coolant tested to see if combustion gasses were some how getting into cooling system and they have turned up negative.

Trained diesel mechanics from Ga to TN can't find the problem and are scratching their heads.\

Has anyone ever heard of a problem like this. If so please send any suggestions.

I forgot to mention it is in a 92 FORETRAVEL GRAND VILLA UNIHOME

HELP

Title Edited by Moderator Jeff for clarity

Re: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #1 –
IIRC on some of those 5.9 there is a wire in the lower radiator hose. If it has rusted away and failed it will cause the hose to collapse which can cause problems like this. It can be hard to figure this out as the hose will look fine at idle but under load it can restrict flow.

On a side note with that age engine did you fix/check to see if the killer dowel pin has been addressed in the past. If not you may want to do some research as to risk of not checking.

Mike

Pamela & Mike 97 U 320

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

Re: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #2 –
I have not owned a 5.9 but a failing head gasket will cause that problem in other engines.

TOM
SOB (Some Other Brand) division
1995 Wanderlodge WB40
8V92 :D

Re: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #3 –
What is the history of the engine,could possibly be a pitted liner,a pinhle from the water jacket area thru the cylinder wall,did they
use a Cummins head gasket?,may try retorqulng the haed,have you checked the oil for coolant.Where near Tenn. are you?
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #4 –
Quote from: Pixilated –
We are having a problem on a 6BTA 5.9 Cummins with bubbles and coolant going into surge tank to the point of overflow. Also engine will start to overheat after a while.

I forgot to mention it is in a 92 FORETRAVEL GRAND VILLA UNIHOME

HELP

Title Edited by Moderator Jeff for clarity

Easy Peasey.

Start the engine, and slide yourself under the radiator and give the lower radiator hose a squeeze.  If you can collapse it, you've found your problem.

But if the bubble appear soon after engine start, I'm afraid the head needs to come off again, block and head re-checked for flatness or damage.

How many times has the head been retorqued?
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #5 –
Quote from: John44 –
What is the history of the engine,could possibly be a pitted liner,a pinhle from the water jacket area thru the cylinder wall,did they
use a Cummins head gasket?,may try retorqulng the haed,have you checked the oil for coolant.Where near Tenn. are you?

No, the Cummins B 5.9 liter is a parent bore engine, not a linered engine.

Head gasket-- another possibility.  Worse case, cracked head.  But, lots of these engines around (Dodge PU) and lots of parts available.
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: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #6 –
Is it possible that the radiator hoses are crossed?
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #7 –
How about history? When did this start? How hot did it get?

Purchase a products of combustion tester from a parts store or take to a radiator shop where they can test it.

If positive, re-torque heads. If not confident or don't have tools, go to next step.

That failing, use a head gasket sealer from parts store. They work well and have had personal experience. I posted about this last month.

Last resort is to pull the head.

Pierce

https://www.youtube.com/results?search_query=head+gasket+sealer
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #8 –
Actually, the B engine head is not that difficult to pull.

If indeed there are combustion gasses in the coolant, I would pull the head, knowing that I would be replacing the head gasket.

While off, have the head checked and of over 100k miles, may even have a valve job done. If a long-term coach, pull injectors and have them checked/replaced with reman.
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: Air bubbles in surge tank - 6BTA 5.9 Cummins - 92 FORETRAVEL GRAND VILLA UNIHOME

Reply #9 –
What happened to Pixi?
96 U270 BUILD 4810
85 380SL
Drummonds TN.