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Jon Wehrenberg
10-14-2009, 05:45 PM
Andre and Brian need a special thanks and all owners need to consider a potential problem may exist.

From my coolant header tank I have 3 small diameter hoses going to various points related to the cooling section. At OKC Brian and Andre alerted me to the fact that while these hoses look good, they may actually be ready to fail.

Brian got hoses for some of us at OKC (thanks Brian) and as I began the process of replacing those hoses I found out how bad mine were. I have a 96 shell. My hoses were no longer flexible and during removal two of them snapped at the fittings like they were dried twigs. The hoses did not crack, they were so dry and hard they snapped completely in half.

Do yourselves a favor and look for the three small diameter coolant hoses coming off the header tank. Try squeezing them and if they are not plyable and able to be flexed you can be sure they are about to fail. If any one breaks you will have a sudden loss of coolant.

Thanks again Brian and Andre.

dale farley
10-14-2009, 06:14 PM
Jon, I second your comment. Brian mentioned this to me, and when I checked mine, I found them to be very brittle. I will be replacing mine before I go on another trip of any kind.

lonesome george
10-14-2009, 07:10 PM
I replaced the three small hose coming from the surge tank last fall and also noticed the 1" hose that runs from the tank to a fitting just under the water pump was being chafed by the turbo inlet tube and one of the water pump hoses, this hose was still soft but it had a couple of good scuffs on it and that one got replaced too.

phorner
10-14-2009, 09:30 PM
Is there any special supplier of these hoses?

Would Prevost be a resource or do we simply need to know the diameter and length?

Thanks....

BUSTER
10-14-2009, 10:04 PM
I would greatly appreciate if someone could post pictures of these hoses in question.

Thank you very much

Kenneth Brewer
10-14-2009, 11:20 PM
My 98 Cherokee blew a heater return hose at the radiator a week ago, fortunately while I was very close to home (by the way, I vote for Kerrville). While cutting off the end of the hose and reattaching it to get home helped by a deputy sheriff, I noticed the engine return hose was about to go as well. Called the local Jeep/Chrysler dealer for an estimate and appointment to replace all the water hoses. Price quoted: just over $535. Cost of the hoses from NAPA: $94.22.

You may submit your comments about the state of (the auto) business now, if you like. For the money I saved, I'm going to treat myself to a second DirecTV tuner, so I can watch satellite TV on one set, and not have to fight my wife about having to see the same program on the other.

That is all.

BrianE
10-14-2009, 11:22 PM
Andre called my attention to these hoses at OKC. After checking mine and verifying how brittle they had become, I had some made for Jon, Harry and myself at a local hydraulic equipment store during the rally. The replacement hoses are standard 1/4" fabric covered hydraulic hose with 1/4" female JIC straight ends. The two longer ones that go from the surge tank to the top of the engine are 41" long. The hose that goes to the radiator should be measured due to a change in radiator configuration in about 1998. Will try and post a picture tomorrow.

GDeen
10-14-2009, 11:49 PM
Thanks for the info on this....

HarborBus
10-14-2009, 11:55 PM
Good to know. Thanks.

dale farley
10-15-2009, 10:47 AM
Brian,

Did you just take a description (similar to your post) to the hose shop and get them made? I think you told me you hadn't done the replacement yet, so I assume you hadn't removed the hoses?

BrianE
10-15-2009, 11:42 AM
This Catview parts catalog graphic does a better job of showing the hoses than a photo would. The hoses are items 16,17, & 18. The length varies considerably per the parts manual which lists the lengths by bus serial number. The original hose type was changed in 2000 to a Gates Green Stripe equivalent. IMHO you would be much better off to measure the hoses on your bus and have them made locally using a high quality stainless steel core hose such as hydraulic hose with crimped end fittings. Silicone or Green Stripe hose would also be an option but they are not as durable. On both Andre's and my bus one of the engine block hoses was rubbing on a 1/2" pipe fitting on the block end of the hose. Rotating the hose block fitting slightly solved this problem. Since this fitting is a pipe fitting and it needed to be unscrewed slightly, check it for leaks if you need to move it.

Kenneth Brewer
10-15-2009, 12:38 PM
A suggestion: I would be careful and check with Prevost and/or the antifreeze manufacturer before going to stainless steel in contact with coolants. Stainless steels (and there are many kinds, metallurgically) are subject to corrosion cracking in the presence of most chlorides and water.

Jon Wehrenberg
10-15-2009, 12:57 PM
I don't believe the stainless ever contacts the coolant. It is a braid and part of the outer reinforcement to resist internal pressures.

All the fittings on my hoses are zinc or cadmium plated steel and they attach to brass fittings.

dale farley
10-15-2009, 02:47 PM
Brian, Thanks for the picture and info.

Kenneth Brewer
10-15-2009, 02:55 PM
I don't believe the stainless ever contacts the coolant. It is a braid and part of the outer reinforcement to resist internal pressures.

All the fittings on my hoses are zinc or cadmium plated steel and they attach to brass fittings.

You are right. I shouldn't have commented. I was thinking of SB! or SB2 hoses; braided SS on the outside, corrugated SS inside, and choice of fittings on the ends, and they wouldn't be used on this service anyway.

Jon Wehrenberg
10-15-2009, 09:59 PM
Here is a picture of the hoses that need to be replaced. Mine literally broke like they were China not rubber.

The new hoses (3) have the shiny silver fittings.

JIM CHALOUPKA
10-15-2009, 10:35 PM
I checked my hoses out at the rally under the tutelage of Sawdust, he went through the learning curve in Michigan some three weeks ago.

We found that due to superior maintenance by the previous owner, mine had already been changed.

JIM

sawdust_128
10-16-2009, 12:45 AM
These are the same hoses I replaced this summer while I was at Flint Michigan. I believe it was CarQuest that made them up for me. They were hydraulic lines. They were replaced with a rubber & synthitic hose material. That material encloses the stainless steel mesh. These are good to 600 degrees and 16,000 lbs.

I told them that 16,000 was overkill. They pointed out that the 600 degrees F wasn't and in the engine compartment where these are routed, heat was the cause of the hose failure.

Jon Wehrenberg
10-16-2009, 08:05 AM
Did you tell them the hoses carried liquid coolant and not superheated steam?

dale farley
10-16-2009, 06:27 PM
I'm glad Ed mentioned that CarQuest made hoses. I wasn't aware of that until today. I went to my local CarQuest and got all 3 hoses made of 5800 lb, flame resistent hydraulic hose for a total of $49.21 including tax.

Larry W
10-16-2009, 06:41 PM
Today I thought boy I had better check these hoses. Our bus shell has a manufactor date of 6/99. I asume this is towards the end of the rivet coaches. All the hoses from my coolant tank are Gates green stripe heater hose. The small ones are 1/4 inch green stripe hoses. All have simple worm drive hose clamps holding them in place. Looks like all I need to carry is a piece of 1/4 " heater hose and a piece of 1" hose. The hoses are all soft and flexible after 10 years

Kevin Erion
10-16-2009, 07:14 PM
I have not seen any with hose clamps, I wonder if someone did things the easy way?

Denny
10-16-2009, 09:05 PM
My bus, 1998 chassis, has the same setup. Gates hoses and hose clamps that are still flexible.

dale farley
10-16-2009, 09:30 PM
One suggestion I would make to anyone else changing the hoses is that you get one of the hoses about 4" longer than the original. Mine were 36" each. The ends on most hoses made by a shop are rigid for about 2 or 3", and this makes one hose a little shorter than I would like it to be. It just doesn't give you the slack to comfortably tie them together the way they were originally. This is not a big problem, but it would be a little better with a little longer hose.

dale farley
10-16-2009, 09:59 PM
I am wonering if Larry W's bus is a 40' like Denny's? Maybe Prevost used a different configuration on the 40 than the 45?

Larry W
10-16-2009, 10:16 PM
Bus is a 45 xl

dale farley
10-16-2009, 10:38 PM
So much for that theory!

Larry W
10-16-2009, 11:55 PM
I think it may have to do with the production date. Prevost made the change maybe.

sawdust_128
10-17-2009, 02:29 AM
Did you tell them the hoses carried liquid coolant and not superheated steam?



Yes, are you wearing your hat? Carquest uses this material with the hydraulic lines they make up. My coach had hydraulic fittings installed for these hoses. Even still, I am comfortable with the 600 degree F rating after seeing what happened to what was installed.

Also, I agree with what Dale said. When I sized mine, I added the length of all the pieces :eek: I recovered and added 4 inches to that and divided by 2 for the hoses to the engine.

dale farley
10-17-2009, 11:22 AM
In looking at a picture I made before removing the old lines, I see that the one line was pretty snug to begin with. I am referring to the one that attaches to the bottom connection on the tank and goes to the lower connection on the engine.

dale farley
10-17-2009, 12:55 PM
This is what my worst hose looked like where it was attached to the engine. It wasn't wet until I took it off, but it could have been leaking at any point. This end was hidden under another pipe, so it wasn't readily visible by casual inspection.

sawdust_128
10-17-2009, 01:44 PM
Yep. Those are the ones. Those fittings are no longer used. The crimps do not work with the newer hoses. The new hoses will connect, but the crimp is entirely different. Also, these newer hoses are NOT compressible by hand. You cannot use hose clamps on them and get them to seal.

There isn't a huge amount of pressure on these lines. Rubber hoses with calmps could be used. However, I think that in the engine compartment, there is a need for a higher level of heat resistance. I also like the stainless steel reinforcement.

flyu2there
10-17-2009, 04:22 PM
Damn, add another to the pending failure list.:mad: Looked fine but a hefty wiggle and....crack. Obviously this is a heat issue, thinking about wrapping them in 1/2" aircraft fire shield. Local tractor store made the replacement up in about 10 minutes...60 bucks.

John

flyu2there
10-17-2009, 04:46 PM
By fire shield I was referencing this...or something like it http://www.aircraftspruce.com/catalog/eppages/thermoflex.php 10 feet of 5/8's would do it. Course option #2 is http://www.aircraftspruce.com/catalog/eppages/thermoshield.php tape.

Don't really know if the ends justify the means but it is a thought.:cool:

John

dale farley
10-17-2009, 08:49 PM
John, I know what you mean about the wiggle. I wiggled mine the day before I left OKC and the next morning I saw a couple drops of antifreeze. I was holding my breath on the way home, but I didn't see any more leakage. I did a visual check every time I stopped, but I didn't do any more wiggle testing.

Jon Wehrenberg
10-17-2009, 09:24 PM
I don't think it was a heat issue as much as it was the selection of the wrong materials by Prevost when the coach was built.

My coach is like everyone else's and I have a lot of plastic, rubber, vinyl and other materials in the area of the engine and they aren't hardening and cracking like these hoses. And mine snapped like a dried twig at the header tank, the one area in the engine compartment that is ventilated by the radiator fan better than anywhere else.

jimshoen
10-20-2009, 12:06 AM
Just finished replacing the three 1/4 ID coolant hose from the surge tank. Mine were exactly as advertised, brittle and hard. The one connected to the thermostat housing just snapped off after about one third of a turn. I ended up replacing them with Parker high temperature fluid hoses. Good to 250 PSI and 300+ F. These particular hose are blue in color. FYI.

Richard Barnes
10-20-2009, 12:36 PM
Jim where did you buy them?

jimshoen
10-20-2009, 04:30 PM
Richard,
Bought the hose at the Parker Store in Reno called 'Hose and Fittings'.
These are nothing special and you should be able to find comperable product at any industrial hydraulic supply house.

GDeen
10-28-2009, 03:39 PM
Couple of things - I moved my bus out of the barn last Sunday to sweep out the place and circulate some fresh air in the coach. When I pulled it in and kicked out the chassis disconnects, I smelled antifreeze. Started diggin around and sure enough at the exact place Dale's pic shows a leak, mine is dripping. Had this on my list but now it is an issue.

Secondly, Prevost has had a fix out for this now for several years it appears. While digging around in their website, I searched for recalls and technical bulletins for my coach. Among 4 pages of items returned is the following - "Improved Surge Tank Hoses." Of course they state right up front this is a non-reimbursable repair. Bulletin is dated Nov 1999.

http://prevostparts.volvo.com/technicalpublications/pdf/Mi99-37.pdf

Larry W
10-28-2009, 05:16 PM
Looking at the Prevost update I find my chassis is beyond the Vin's listed (X6978). Guess that is why I have green stripe Gates heater hose to the surge tank.

GDeen
11-07-2009, 10:58 PM
Changed these hoses out today. Amazing how truly brittle they were - I just snapped them into small pieces to throw them away. Nothing else in the engine bay is in near as bad a condition as those were.

hhoppe
11-01-2011, 11:55 AM
Other Coolant Hose Failure: I had a failure of the coolant hose from The engine block line to behind the Webasto. Access to the leaky hose behind the webasto cannot be reached by hand from the bottom or from the Webasto access door on the 2000 Liberty. I'm awaiting word from Liberty on possible access to the end of the hose. I was able to isolate the large leak by closing a valve behiund the Webasto copper piping maze. I suspect all of these water hoses are due to be replaced due to their 11yr age. If anyone has been through this wonderful task I would aprecciate any heads up help on getting it done. If I ever hear back from Liberty on the subject and get the replacements done I'll offer a blow by blow description of the process. In the meantime all the hot water valves in the vacinity of the webasto are closed.

charlesebrownjr
11-01-2011, 09:51 PM
Did mine a year and a half ago while in Nashville. Jon, mine were in the same condition, looked fine from an appearance standpoint but were hard as a rock. New fittings and hoses and also the engine coolant hoses. Now I am in the process of replacing all the big lines in the rest of the engine room. Being a 98 I am sure they have had just about all the heat they can stand.

Jon Wehrenberg
11-02-2011, 09:07 AM
Each conversion has different ways of routing coolant hoses and different ways to use heated coolant, such as to heat hot water or defrost the windshield or heat the engine block. Liberty uses a Webasto and plumbs it in various ways depending on the length of the coach or type of coach. Others use AquaHot. However coolant is routed for heat transfer there is one constant that applies to all coaches. That is the coolant hoses will eventually need replacement.

Like Harry I got a leak in my previous coach and it was in a hose that looked perfect. Once I got into the task of replacing hoses and hose sections it became apparent some hoses were brittle, some were overly soft and appeared to be failing internally, and some hose clamps looked great, but on inspection had rusted to the point where they were merely sitting in place and were not clamping tightly. So with a very good scare my coolant system hoses (except for the blue engine hoses) are on a 10 year replacement cycle. Like Harry's some are miserable to get at, some are hidden(such as in the water bay onlhy visible by removing panels) and some are easy to access. In Harry's case and mine access is only from a door or from beneath and there is a lot of blood and scrapes associated with hose replacement. But it has to be done.

The loss of coolant is one of the reasons a coach will shut down. There is no benefit to delaying a necessary hose replacement.

kenrobertson
11-02-2011, 11:00 AM
Hi Harry - Don't know if you've heard back from Liberty yet, but we recently had a very similar repair and found that unbolting the Webasto and moving it aside allowed pretty good access to the hoses behind it - Obviously, while in there, we replaced ALL the hoses at the same time. If you have any questions, give Rick May a call.

Good luck,

Ken

hhoppe
11-10-2011, 03:05 PM
Big thanks to Jon, Ken and Bill Doherty of Liberty. Lots of good information much needed here. The gory deed will be attempted on 11-15 by West Coast Frame in West Sacramento. Bill explained a sequence of bed lift removal and an access panel under the bed and above the engine. also the panel at the water heater location to remove the supply and return hoses to and from the engine. I will be back here with a complete blow by blow description of all phases of the operations. I intend to replace all hoses in connection with the heater systems and webasto.

Gary Carmichael
11-11-2011, 09:48 PM
Looking forward to this, photo's if possible Thanks Gary

wmoureau
11-22-2011, 02:19 PM
Changing the coolant hoses on a 1997 Liberty, and cannot remove one of the hoses. The one connected to the radiator in the foreground. Can I loosen the large hose in the front without complications? Have pic on my hard drive but cannot attach. Please advise.

Thank you,
W Moureau