Changing squirrel cage blower seals Whew! what a job. Gumpy???

[RickB]

First of all,

I am not the brightest bulb on the tree.

I have a day off so I decide that it's not too cold to work on the bus today.That was my first mistake.

Second was thinking that changing these seals would be easy. NOPE. As far as I can tell I have to drain the antifreeze, remove the main supply pipe to the radiator, remove the overflow reservoir and then the mother of all jobs, I have to loosen the entire blower drive assembly to get the clearance needed to flip the housings up on their hinges. If the above is doing it all wrong somebody please speak up.... Gumpy didn't you tackle the squirrel cage issue.

I am definitely waiting until it warms up to really dig into this.

Thanks, Rick

[Brian Diehl]

Rick, on my 96A3 I did not need to do anything with the coolant system.  I was able to unbolt the blower housings and the blower drive.  Then, with a lot of unpleasant words I was able to work the whole thing out of the bus.  You have to kind of move the blower housings around in just the right way as you move it out of the bus in order to get the housing to clear the blower access hatch door frame.  Why did you think you needed to remove the overflow reservoir?

[RickB]

Brian,
In order to get the new seals on the squirrel cage covers I have to flip the covers up on their hinges correct??

I don't have the clearance needed between the cover and the squirrel cage blower fan inside to flip the housing up. The main supply tube for the radiator rests almost in contact with the housing and the reservoir hit's the top of the housing as I try to manuever it out.

Knowing me I'm probably doing something wrong or that I don't need to do.

And it's still too cold.... Brrrrr

Also the 8"X 4" rubber seal that actually goes around the squirrel cage belt where it runs between the engine compartment and the upper blower compartment is shot. Do I just make my own replacement or is there an actual part made for this?
The PO cut the inside squrrel cage seals and riveted them back together. And I wonder why my bus doesn't like Mountains??? This compartment has more air leaks than the backside of a cow

[RickB]

This job sucks

[JohnEd]

Rick,

From what Brian says the different bus models have different fan chamber configurations or dimensions.  I am pretty sure there are different size squirrel cages to further complicate your task.  I think you are probably dealing with this in the best manner you can for your rig.  Good luck and stay tough.

A question:  Aren't there different model fans that push more or less air?  I think I have see some that close up when its cold to keep from blowing air across the frozen engine.  The biggie.....Isn't there a model that modulates the air flow depending on temp.  That could be the one with the shutter built into the fan squirrel housing inlet.  If you choke off a squirrel I think the cage starts spinning with little energy consumed.  Thats a nice bonus and make sense even more so if you have upsized the blower to conquer heat problems.  I can't recall any discussion but it would make sense if this was part of a 8V92 engine selection from the mfr.

John

[JackConrad]

     The shutter on  the MC-8 and 9 is in the outlet of the fan housing, just above the opening into the engine compartment. The intake is in the ends of the housing.  2 different housings were used in the MC-9 depending on which engine was installed (smaller fans/housings on the 8V71, larger fans/housings on the 8V92).  The 8V71 opening into the engine compartment is approx 7" x 14", the 8V92 opening is approx 14" X 14". 
    Some have modified the 8V71 fans & housings, replacing them with the larger 8V92 fans & housings as well as the smaller diameter pulley to increase fan speed.  Jack

[JohnEd]

Jack,

Thank you.

John

[RickB]

Bump

[Dreamscape]

Thank God us Eagles don't have to worry about that kind of stuff...............Only the flying red dust as we moto down the road!

Good Luck and "Git 'er done!"

Paul

[mikelutestanski]

Hello;
  The blower assembly meaning the  gear box and the squirrel cages should roll out as a unit. First unfasten everything necessary.Then  you can set up a  board (2x6 or 8 by 8 feet long) with the tail gate adaptor on it;  one end on a 6 foot step ladder and the other with the tail gate adapter onto the lip of  the compartment. You set the board up even or slightly lower than the compartment and roll and slide the assembly out of the bus onto the board.
   Then you can lower the end of the board that is on the ladder step and get the assembly to a position where you can slide it off onto a cart or work on it right there. Installation is the reverse except if you can raise the ladder end of the board slightly higher  and roll the assembly back into the bus. The blower cages will be floppy but manageable.
    The mci 7 has the smaller blower and cages and I changed over to the larger units for the bigger engine.  The blower cages will fit but in this  particular case you have to change the lower openings to accommodate the bigger cages  The bigger cages will still fit into a 7 but it is a close fit and you have to  roll them in  carefully.
    This technique should work for any assembly.  Remember when you have it apart to check everything and replace as required. The blower seals are mci parts items .
      Mohawk has parts for the blower gear box but I am not sure if they have the air blower seals.
   I never had to disturb the coolant system in my bus for this chore.    I thought I had a picture of the job but it is lost. 
   Some of this technique is mine but it also came from Howard  PI  Jenner an old greyhound mechanic  gone now; but this is how they did it at the shop in Syracuse . 
   Regards and happy busssin.  mike   

[edvanland]

I had to do all that on my MCI 7 also.  Not being a real computent mechanic I spent a lot of time studying the job.  After several long days of thought and talking to Luke at US Coach I went to my mechanic.  He said O that would not be a problem and queted me a price.  I asked him if that was a firm price, he said yes.  So I said do it.  When I went to pick up the bus he gave me a bill for the price queted, wondered why he looked so grim. When I inquired he said NEVER AGAIN FOR THAT PRICE.
Glad I got the good price. He said he learned a lot from doing the job and next time it would be eaiser for him but it would be on a time basis only.
Ed
MCI 7

[RickB]

Well judging by the earlier posts I have the retrofit larger blowers. Unfortunately, I broke off three of the mounting bolts for the blower seal retainer assemblies and the one blower that I worked on basically started falling apart. I have decided to rerivet and patch it back together and make it as airtight as I can. I am fabricating some retaining clips for the top and bottom of the blowers seals because they like to bow when tightened. As far as the broken bolts are concerned they are not going to be fun. I am trying to see if I can drill new holes and just use bolts, washers and shims to accomplish the same thing. I will use nylon aircraft nuts to keep them from vibrating loose. I can't believe the engineers at MCI could'nt come up with a better blower seal replacement system. Cutting the inside new blower seals apart and their aluminum mounting assemblys as well seems rather inefficient. At best, these negative pressure blower assemblies leak like sieves.
I am committed to getting as much air as I possibly can going through the radiators and as little as possible leaking through the doors seals and the radiator seals. I would imagine expanding foam or weatherstripping caulk is going to come in handy to seal all the little air leaks.
The good thing is my blower assembly itself looks like it was gone through at the same time the PO rebuilt the motor, tranny, brakes, suspension, it doesn't seem to leak oil at all.
That's why I am avoiding removing the entire assembly unless I absolutely have to. Anybody else break off those press riveted bolts on the sides of their blowers?? If so, what did you to fix them??

Thanks,
Rick

[buswarrior]

Yes, the expanding foam is a lovely, if unconventional solution to getting the spaces around the rads sealed up.

What inspired you to mess with the blowers before getting all the gaps and seals freshened up?

MCI was not concerned with busnuts operating the bus long past it's best before date...

Air leakage is the number one big failure in cooling a squirrel cage MCI.

Fix the leaks, the problem may be over.

happy coaching!
buswarrior

[RickB]

Well I decided to take the whole blower assembly out and found that when they put the oversize 8v92 blowers in they must have finished the job by framing in the back door AFTER putting in the fans. I literally had rivets popping as I tried to fit the second hood assembly through the opening the first one I removed has kind of disintegrated. I am thinking about having a fiberglass company do a mold of the inside of the shrouds. It would get rid of these metal shrouds and fix the clearance issues I have. I may see if I can have them made out of Kevlar. I also noticed that one of my radiators is leaking. I thought they had been rebuilt or replaced when the bus was converted in 2000 but I guess corrosion does doesn't have an odometer. So, I will be pulling both of those now as well, and I have read that removing the radiators is as sucky a job as I just started

This was difficult work because of the lack of room to do anything. That blower drive assembly was really heavy for one person. I would like to sandblast the whole shebang like Gumpy did but am concerned about that sand/dust going in my engine next time I start it.

This was probably not the smartest thing for a guy who makes his living playing guitar to do. I probably should have hired it out. Although I can't imagine how much that would have cost me.

[paulcjhastings]

Kevlar is severe overkill for what you are doing, secondly (remember I have a Setra so I'm unfamiliar with those blowers) how would making it out of composite save room vs. sheet metal? If you are still in MN and decide need help w/ composite work let me know and I'll show you what to do.