Skip to main content ↑ ↓
Topic: Coolant Boost Pump?? - Next Questions. (Read 765 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Coolant Boost Pump?? - Next Questions.

Yahoo Message Number: 65056
Thanks for all the suggestions. I finally found the pump by feeling for vibrations and found slight vibrations on the left frame rail, heavier vibrations in the forward left engine mount, and finally found a pump mounted out of reach near the floor of the coach. I was able to reach the pump with a piece of water pipe and found the source of the vibrations/noise. Since there's no way to reach the pump from under the coach, we started pulling fuses until we found one in the steering bay that stopped the pump.

=== Next Questions ===

The coach floor steps up about 8" above the engine and has an access cover 5' x 2.5' with a "D" ring. I would be able to fix the pump if I could remove the access cover which is about 40% under the bed which is mounted to the slide.

1) Are there any suggestions for removing the cover without removing the entire bed from the slide?
2) What is the purpose of that pump and the one behind the front bumper? Are they for the in-dash heater, or the hydronic heat?

Don

2000 Affinity #5681

Re: Coolant Boost Pump?? - Next Questions.

Reply #1 –
Yahoo Message Number: 65065
Don,

Since I have not seen, anyone answer, your post I will explain what I do to remove my engine cover and how the Coolant Boost Pumps work on my coach.
I have a 2003 Allure, which also has a similar change of height to access the engine cover. What I do is to lift the bed until it is almost upright. The bed will remain upright allowing me to have better access to the engine cover. I then lift the edge of the engine cover closest to the wardrobe door while at the same time sliding the bottom engine cover towards the wardrobe. Once you have the engine cover clear of the bed very carefully lean it against the wardrobe doors. Mine, are mirrored so I take every precaution not to do anything to damage them. If your engine cover is as heavy as mine see if someone can help you.

Second question:

On my coach, my Coolant booster pumps only work with the dash heater.
I hope someone on the forum will specifically answer your questions.

Regards,
Jose' Ferrer

2003 Allure #30863 w/Tag

Re: Coolant Boost Pump?? - Next Questions.

Reply #2 –
Yahoo Message Number: 65082
Don,

I have coach 5801, a 2000 Affinity, all electric, Bed and Breakfast floor plan. Assuming you also have the B&B, I can tell you how to gain bedroom access to the engine compartment. Unless there were changes on the assembly line, you will find a coolant pump mounted under the floor, centered, close to the forward edge of the floor opening. As I am not currently at my coach to test it, I can't verify that this pump starts running as soon as the key is turned to accessory - but it may be, as I always hear plenty of action just prior to engine start. What I have verified is that when I turn on my Webasto (sp?)furnace that coolant circulating motor runs along with one beside the Webasto and one in my central electric bay (with the inverters.) The coolant motor mounted up front doesn't run until I activate the dash heat controls.
If my memory is correct, look in chapter 5 about page 20 in the Owner's or User's Manual and you will find a diagram of the hydronics/coolant flow. Personally, I think coolant flows through most of the system whenever the engine is running and is not limited to simply cooling the engine. This would explain how your domestic hot water is heated by the engine when the tank looks to be the last point of circulation before coolant returns to the engine. Note that you may have one less motor than me if you are not all-electric.
Key to engine access in the Bed & Breakfast is knowing that the carpeted wood access door is hinged under the carpet so as the "D" handle is pulled up, the door bends across and must be slid rearward toward the rear drawer cabinet. First you need to clear access by removing the vertical carpeted strip just above the door and under the "toe access" lip of the cabinets. I also have to remove the carpeted, non-sliding vertical piece that rests on the carpet floor mostly on top of the raised "step."It looks like a lower, non-moveable, part of the bed frame. Unfortunately, this last piece requires that you remove the mattress and plywood bed top. (I removed the plywood access door and marked the plywood hole edges on the underlying support rails to help alignment on reassembly.) Second, remove enough (maybe 2) screws from the small block which joins the foot-of-the-bed vertical support (with the ventilation grill) from the rearward curve part (vertical piece at the foot of the bed, closest to the rear cabinet/closet.) Now look inside this curve area for a small base attached to the carpeted vertical piece you are trying to remove. This "base" is "flush" on top of the carpet and secured with 2 long, bolt head screws, which must be removed. If you haven't already, extend the slide for under-bed access. Look inside and under the rearward edge of the bed frame and you will find 2 more bolts closer to the head of the bed and still on top of the "step." With these last bolts removed, the vertical piece is free to "float" up as you attempt to slide the access cover up and to the rear with the "D" handle. Note that I actually removed the screws all around the frame (4 sides) from the bedroom "slide" structure so that I could raise the foot enough to remove the vertical straight and curve piece intact and get it out of the way. I don't know for sure if this last step is required or not - but it gives a little more room for maneuvering the carpeted door out.) The last step before removing the carpeted "door" is the remove the screws from each corner of the door and perhaps midpoint in front of the cabinets. You will find the screws down in the carpet about an inch from the edges. The door is difficult to fold and you will want to keep from scratching the drawer cabinet so two people and removing the drawers are virtually a must in this tight fit!
Once the carpeted piece is out of the way the next challenge is to remove the 10 bolts holding the real wooden access door in place without twisting off any bolt heads due to corrosion. The good part is the nuts are welded in place under the floor. This is where I turned the access job over to a repair facility until they twisted off the first bolt and refused to continue when the found the remaining bolts all "tight." I got two out for each one I broke by going easy with a little forward pressure, then reverse, etc. An "extractor" tool was required for the broken bolts and you want to avoid this if possible. I also replaced my bolts with slightly shorter and higher grade bolts - well lubricated! Unfortunately subsequent access has been required, but the bolts come out with ease
My other caution is to cover your carpet/bed frame, etc. well to prevent any soot, grease, etc. I used a sticky sided carpet runner which came on a roll that I stuck to the carpet and the wood all around the hole. Then as I raised the front edge of the access cover so that I could slide it forward an inch or so and then start sliding it sideways, away from the headboard, I slid the door into a large garbage bag to contain all the dust and soot on the bottom from the engine compartment. Note: When I recently had CAT engine work done by Wagner CAT in Denver they "draped" the whole coach inside from the doorway to the engine access with a single piece of heavy plastic which they taped to the windows and cabinets along each side about shoulder high. It formed a one-piece tunnel or trough that workmen could walk through with no chance of footprints or handprints. They said it was a lot cheaper than having to clean or replace carpet!

Kent McCoin 2000 Affinity 5801 803-364-2911

Re: Coolant Boost Pump?? - Next Questions.

Reply #3 –
Yahoo Message Number: 65093
I have a 2001 Affinity, 42' B & B. and I'm a bit familiar with the pumps.
My coach has two pumps. The first one is located in the rear passenger side bay, near the Hurricane heater. It is mounted on the far inside of the floor of that bay. It is mounted in a horizontal manner. The second pump is located way up in the front of the coach, on the passenger side. The front one is mounted to a plate which is welded to the passenger side frame rail. The front pump ( MP Pump is pump # 29924) was mounted vertically with the motor on the bottom. This is an INCORRECT MOUNTING according the manufacturer.
Their web site instructions warn of this problem. I called them ( MP -- 800-563-8006) to confirm and spoke with several people. A man named Vance called back and confirmed that this will cause a failure. His private line is 586-415-1318. His said that last winter they got quite a few requests for new pumps due to water leaking in from this mounting problem.
The reason for the failures he said was due to the fact that there are openings in the pump, and when placed with the motor in the bottom position, water droplets go down into the motor and destroy it.
Hopefully my new pump will arrive tomorrow and I will install it in a horizontal manner.

Good luck, Den........ 2001, 42' B&B Affinity, # 5972

Re: Coolant Boost Pump?? - Next Questions.

Reply #4 –
Yahoo Message Number: 65163
Wow, thanks for all the information!
I will wait until we get to Benson AZ for the winter before starting a project that big. I may try to see if there is a way to rebuild the access so that it will be more direct.

Don & Sue

2000 Affinity 5681

Re: Coolant Boost Pump?? - Next Questions.

Reply #5 –
Yahoo Message Number: 65170
If you have the original pump in front of the engine try to recon -figure the impeller end so it doesn't;t collect all the trash from the engine cooling fan. Do you have the pump disabled ? AL

00 Affinity

Re: Coolant Boost Pump?? - Next Questions.

Reply #6 –
Yahoo Message Number: 65177
Hi Don,

I just came across this web page. This is the installation manual and specs.......web site for the pump in your question #2 below. This pump supports the hurricane heater, and helps circulate the fluid all the way from the back of the coach. The pump helps supply warm fluid to the Hurrican heat elements located under the front dash and then pushes it back to the rear heating elements.
Den

http://www.mppumps.com/non-html/catalog/transportation/MP_Pumps_Transportation_Catalog_2010.pdf
++++++++++++++++++++++++++++++++++++++++++++++++++++