Water Pumps, Hydroboosts and Automobiles

[swebster]

Alan,
If I did had it to do over again (both the water pump and the hydroboost pump at the same time and I was in the driveway) I would have pulled the grill and radiator and done it that way. Even with the oil and tranny cooler lines, getting at everything is easier from the front.

As Brett mentioned the 345 has a large doghouse opening which extends past the nose of the engine and since I removed my AIR pump (it left a big gap in the accessories space right in the middle of the engine) things are fairly accessible from the top. But just trying to see everything to line up bolts and get brackets out of the way is best when approached head on. On your 280 you may end up approaching from underneath, in which case you would need to remove the lower fan shroud at a minimum.

I'm also not a mechanic, just an insane classic motorhome owner so there may be better, faster ways. This is simply what I did.

Having said all of that....

Get your digital camera and take a ton of pictures of everything before and during the disassembly. Once I got everything back together I could not remember the belt routing and ended up "flipping" a belt on the drive home. It only cost me a belt, but it was a real puzzle trying to figure out which pulleys lined up with which when you can't really see in there.

Get a five gallon bucket, remove the radiator cap and open the petcock on the radiator to drain the coolant into the bucket. Mine sits over the frame rail so I used a short length to tubing to direct the flow into the bucket (after I got it all over myself first ).

I started by removing the fan/clutch assemlby. I had recently replaced mine so the bolts were easy to remove. If you can, loosen them while the main serpentine belt is still on. It will give you some resistance as you loosen the nuts from their studs. You can pull the 12V into the distributor and "bump" the engine with the starter to turn the fan so you can loosen the lower two nuts. Move the fan/clutch assembly out of the way (ideally down and out where the lower fan shroud was located.

Once they are loose, disconnect the battery, back off the alternator tension and remove the serpentine belt.

In mine the alternator shares a bracket with the second AIR pump on the passenger side of the engine. The AC and Hydroboost Pump are on the right and each have their own braket.

Next, I removed the alternator from it's bracket. I left it attached to the harness and just slide it out of the way. Then I remove the bolts that attached the passenger side bracket to the front of the engine, leaving those on the side attached. This should leave you enough flex in the bracket to slide the pump down.

I then released the AC compressor bolt and loosened the tension screw and removed the AC belt. Then I loosened the hydroboost pump (big 3/4" socket on a short extension fits this well but if your pump is running a shorter belt the pump pulley may cover the bolt so you'll need to make about 50 1/8" turns with an open ended wrench to get this one out. You can then "push" it over toward the master cylinder to get it out of the way. Use your hands for this and not a big screwdriver

Now the fun part. Again, I removed the front bolts on the AC bracket, one of which is also a bolt through the water pump. Mine had a lot of spacers and a combination of long and short bolts. Make sure you note where these go. Again, a digital camera is a good idea. on this side before you remove everything. Unlike the other side, on mine, this bracket is cast aluminum and requires that you remove the side bolts as well. Access to the side mount was easiest from the driver's side wheel well. This should free up the driver's side bracket.

Now you can remove the lower radiator hose (get a bucket as a lot of coolant comes out of this hose) and remove the three remaining water pump bolts.

My pump practically slid off, but it was replaced only two years ago. When I replaced the one that failed I had to whack the pump pretty hard with a rubber mallet to break the old rust and gasket seal. Once it's loose you can sort of slide it down toward the crankshaft pulley and remove it.

A quick word on replacement pumps. I asked for a reman pump at AutoZone. It was $25 with a $25 core. The guy suggested their new pump with the lifetime warrantee for $50. We put the two pumps next to each other on the counter and I spun the shafts on both. The difference was amazing. The feel of the new pump next to the reman was silky smooth. For an extra $25 get the new pump. BTW - The pump that failed was a reman.

Also get new hoses, belts, coolant, a gasket scraper (small) and a can of gasket remover. I would also recommend replacing the fan clutch while you have it out if it's in the budget (another $50).

The part that takes a while is removing what is left of the old gaskets. I sprayed them with gasket remover, let them soak and then use the scraper on them. It takes about ten minutes for the remover to work and I repeated it about five times on each side. Needless to say - it takes some patience. This is also a good time to use a mirror to "see" what is left on the block.

Once the gasket is removed you can slide the new pump up in there from the bottom. I inserted and finger tightened the upper and lower bolts on one side to "hold" the pump against the block. Then I slide the paper gasket on the other side so the bottom hole lined up with the top bolt hole. I then inserted the top bolt and "spun" the gasket around between the block and the gasket. Then I inserted and finger tightened the lower bolt. I then removed the bolts on the other side and did the same thing, spinning the gasket by using the top bolt as a pivot.

Now you bascially just start bolting everything back together again. This is a good time to refer to your earlier pictures to check placement of bolts, etc. Make sure you re-installed absolutely everything. You don't want to have a bolt left over at the end of this one.

One note on the lower radiator hose. On mine the pulley is pretty close to the hose and the belt actually rubbed the hose. So when I re-installed it I did not push it all the way onto the pump. I just went on about an inch or so and double clamped it. This gave me the clearance I needed so the inner belt didn't rub the hose. Fill the coolant back up and check for leaks.

Lastly, install the belts as they were routed before and tension the pulleys (Do I need to say "don't press on the side of the hydroboost pump with a big screwdriver" ? . There is a 1/2" socket square in the bracket for tensioning this pulley - use a breaker bar or socket wrench on it). I like to spin everything a few times with the starter. Correct any loose belt or routing, reconnect the ignition and test fire it, check for leaks, loose belts and correct.

It took me five hours to do it alone. If I were doing this repair in the driveway I would break it up and plan on a weekend. Saturday to remove it and Sunday to re-install it. I also think a person on top and a person below would make the job go faster. Even if one person is just "holding the light" it would save time. There is just not much access or room in there and sometimes I would need to get out of the motorhome and crawl underneath to "feel" where something was so I could get to it again from above. Another set of eyes would be a big help.

The other thing you could do is drive up to Louisville with a case of Atlanta's best beer and we could tackle it in my parking lot. It could be a micro rally!

[87MH]

Originally Posted by swebster

Alan,
If I did had it to do over again (both the water pump and the hydroboost pump at the same time and I was in the driveway) I would have pulled the grill and radiator and done it that way. Even with the oil and tranny cooler lines, getting at everything is easier from the front.

....I removed my AIR pump (it left a big gap in the accessories space right in the middle of the engine) things are fairly accessible from the top.......In mine the alternator shares a bracket with the second AIR pump on the passenger side of the engine.....Also get new hoses, belts, coolant, a gasket scraper (small) and a can of gasket remover. I would also recommend replacing the fan clutch while you have it out if it's in the budget (another $50).

It took me five hours to do it alone. I also think a person on top and a person below would make the job go faster. Even if one person is just "holding the light" it would save time...Another set of eyes would be a big help.

Steven:

What a great "this is how it's done" epistle.

On your description of the AIR pumps – were you able to remove them totally, or did you have to leave them partially in place in order to utilize the pulleys as free wheeling guides for the multipurpose belts?

On my 345 (dual AIR pumps) I do not believe I have clearance from above to do ANY work at all on the front end of the engine.

On your description of the “jewelry” replacements – I sincerely hope all classic MoHo owners take the difficulty of replacement to heart, and take the opportunity to replace ALL of the “wear” items when practical to do so….especially during an engine pull. I know it hurts financially to kick in a few hundred more bucks for “little items – especially when the old ones are functioning - but, in my opinion, the replacement of old “things” such as belts, hoses, water pump, alternator, fan clutch, starter, … and others, is a no brainer when the “old” item has to be pulled anyway. Saving a few bucks by not replacing a wear item with a premium rebuilt or new purchase is truly false economy.

On the “difficulties of working alone” - don’t forget the possibilities of getting a son/daughter to “hold the light”, “start the bolt”, “turn the key”…. Working with a younger person does so many things…bonding with a developing personality, teaching the youngster to develop some “common sense” (sadly, grossly lacking these days), passing on the knowledge of the “right hand rule” for tightening/loosening bolts, increase “patience and tolerance” levels when tackling difficult obstacles, and, at the end, to share a “sudsy root beer” to celebrate a job well done by the both of you.

It seems as if you have expounded on many of the basic joys of “Classic” MoHo ownership – the pride of saying “I did it myself”, the knowledge (bonding?) with your Classic by getting to know it intimately, the realization that keeping an old unit running is many times more expensive than purchasing a new (or newer) unit but working on it is still cheaper than paying for therapy, the opportunity pass on information (such as “the master” to “the grasshopper”) to friends, family, and Forum members, and the insight that to get the job done right many times you just HAVE to do it yourself.

Steven, thanks again for sharing your most recent experience in life.

[swebster]

Dennis,
Thanks for the post and the kind words. I was able to remove the top AIR pump and use a different belt for the AC/PS when I replaced the exhaust with headers. This opened up a big hole on top of the engine making access from the top possible. I left the second AIR pump (the one under the alternator) installed but disconnected, so I could continue to use the existing serpentine belt.

I have recently been contemplating replacing the remaining AIR pump with a second alternator. We only run a small 600 watt inverter when on the road but I see the need for more 110 volt juice increasing as our renovations continue. My plans for the media center alone will eat up the output of the current inverter and then some. Not to mention I like redundancy "built in" wherever possible.

I also could not agree more with your comments about taking the opportunity to replace components when you're "already there". The "jewelry" up front is something you only want to replace once and on your timeline and budget - not on the side of the road with your entire family waiting so you can continue your vacation.

Lastly, I really appreciate your comments about little helpers. My son Henry, age 9, helped me many times during the replacement of both pumps. Everything from handing me tools to holding the light. And while his attention wandered from time to time (after all he is nine and what nine year old can spent FIVE HOURS getting tools for Dad when there is a PlayStation onboard with a new copy of Star Wars Battlefront to play) it was truely a pleasure to talk with him about how things worked and why things broke, etc. This combined with my daughters occasionally poking their little heads over the doghouse to say "I love you Daddy" while I was lying on the ground made this roadside project tolerable.

[GlenCoombe]

Air pumps, we don't need no stinking air pumps!
Got rid of mine after installing the headers too Steven.
What I really want to know is how much blood did you loose? Everytime I look at my tool box my hands spontainiously bleed.
It's been so long since I've been under the bus that my hands are divot free! I am planning to check the header and collector bolts this weekend prior to my trip to Florida in a couple of weeks.

[overlander63]

Originally Posted by GlenCoombe

What I really want to know is how much blood did you loose? Everytime I look at my tool box my hands spontainiously bleed.
It's been so long since I've been under the bus that my hands are divot free!

Glen, two words: Mechanic's Gloves. $14.99/pair

[swebster]

Glen,
Lot's of blood. I had to scrub my hands with a stiff nail brush to get the grit out and really felt it with all the cuts and scrapes. I was at AutoZone today picking a spare set of belts and a transmission output shaft bushing and threw in a set of those gloves.

I'm almost looking forward to the next breakdown now.

[mcneon]

Originally Posted by 87MH

I sincerely hope all classic MoHo owners take the difficulty of replacement to heart, and take the opportunity to replace ALL of the “wear” items when practical to do so….especially during an engine pull.

Great advice, Dennis. But I'm afraid there are no guarantees even when you take this belt-and-suspenders approach to heart.

I had a new water pump and all new belts and hoses installed when I did the crate 502 replacement in my '74 a few years ago. Subsequently I replaced the hydroboost just because I figured that, being a very critical component and several decades old, it needed replacing. So far, so good.

Last spring I decided to replace the power steering / hydroboost pump, since it was the only rotating component I hadn't replaced. I used a later style pump with a press-on pulley, the only style available.

A used pulley from eBay went on, too - new ones were not to be had. The pulley was a bit warped but seemed okay on a 50-mile test drive, so, feeling pretty confident, I hooked up the race trailer and headed for Indianapolis Raceway Park 300 miles away.

About 20 miles out of Nashville, I heard the noise - a series of clanks - and quickly lost steering boost and air conditioning. My new pulley had separated itself from the shaft and had taken two of three belts with it. Fortunately it left the alternator belt in place, so I had electricity and engine cooling.

I decided to continue my trip, even though stopping and steering with no power assist was a real adventure. I used my trailer like the Apollo 13 Lunar Module; the trailer brakes in addition to massive foot pressure slowed me when I really needed to stop quickly.

Once I got parked at IRP, I sized up the situation. Luckily the pulley had come to rest on a frame member and was unharmed - very luckily, indeed, since a new replacement was unobtainable. I reinstalled the pulley, leaving in place the bolt used to pull it onto the shaft. I bought new belts at CARQUEST and installed them.

The moral of this story? Replace all of the parts you can with the best stuff you can find, but be prepared. These vehicles are still many years old, and stuff inevitably happens.

Bob in Nashville

[ALANSD]

I have not removed my air pump, give some ideas as to why I should. Drains power? will I have to change the belt routing?

[swebster]

Alan,
There are two AIR pumps on the 454. Each feeds fresh air into control valves above each exhaust manifold. These then pass air through a stainless steel manifold into threaded ports on located at each exhust port on the exhaust manifolds and up into the exhaust port up inside the head.

The concept of the AIR system is pretty simple and one of the early attempts at emissions control. Unburned fuel exiting from the head hits fresh oxygen pumped in from the AIR system, it's re-ignited in the exhaust port, manifold reducing the emissions. Of course, it also means placing a lot of restriction in the exhaust port (picture a small cigar sized tube right up next to your exhaust valve stem in the port) along with increased tubulence in the port and manifold from re-combustion in the exhuast exiting the engine. Lastly, think about the heat this generates in the manifold and we all wonder why RV exhaust manifolds are prone to heat stress and cracks.

I had cracks in the stainless manifols of the AIR system causing exhaust leaks. The price to replace the AIR manifold exceeded replacing the entire ecxhaust system with headers and free flow mufflers.

So I replaced them with headers and could no longer could use (or wanted to use) the system. So I removed the control boxes (located alongside each valve cover) all of the tubing and the upper AIR pump (the one that feeds the driver's side manifold.)

It was a simple removal of the top pump and a new belt to make it all work. I left the other pump in there to keep the alternator belt as is and it' just two darn cramped in there to get at the thing. So it now pumps air to the passenger fender well.

For the WP replacement, you would need to remove this pump for access from the top, or go with Brett's approach from the bottom.

If you leave the existing exhaust system you would need to replace the pump once you were done with the job.

[ALANSD]

thanks. I understto dthe concept, but had not thought about removing it.
The more you read the more you want to do.

[swebster]

So Alan, when are you coming to Louisville for some "maintenance"?

[ALANSD]

are you volunteering? I would like to pop on some Hedman's

[swebster]

I'd be happy to help out. Even have an electical hook up for you at the office. Might want to wait until it gets a little wamer though.