Shutterstat Questions

[richard5933]

Not much I can do right now while recovering from minor surgery, so I'm digging in deep learning about the shutter system on my bus so I can complete the rehab on them in the spring. They work and the shutters themselves are in great condition, but I've got a few minor air leaks I plan to address.

Question right now about the Shutterstat...

Anyone know if there are any functional differences between these two styles of Shutterstats? The first one is the type on the bus right now. The second appears to be a later version of the same thing. The shutterstat on my bus is a 190-degree normally-open variety, and the new style one that I found as backup has the same specs. Same physical size/dimensions. Only difference I see is the inability to rebuild the newer one, at least as easily.

On that note, anyone every rebuild one of these? From the picture in the MCI parts book it seems like a pretty simple thing to rebuild to clean & change out o-rings.

[chessie4905]

Personally, I would go with the new style. Fewer points to leak.

[richard5933]

Personally, I would go with the new style. Fewer points to leak.

Should I assume that they are interchangeable?

[chessie4905]

I'd call Luke to be sure.

[richard5933]

Brief project update...

Found some Shutterstat Fluid - sealed can never used. The oil inside seems to be good and not gummed up. I was expecting an odd smell since it has a solvent content, but didn't expect that smell to be mildly similar to the smell of Windex. The closest thing I've found to it so far was Marvel Mystery Pneumatic Tool Oil. I'll run some side-by-side wicking tests to see how they compare.

The airline filter/oiler on my bus has been on there unopened for 46 years. On initial inspection the screws and fittings seem pretty well stuck and not keen to move. So, when I saw the NOS filter/oiler come up on eBay I got it just in case.

The air cylinder rebuild kit was ordered through Ross Air Works, and the Shutterstat itself was bought from C&J in Minnesota. I'll probably replace the air lines themselves if there is any sign of dryness or cracking when I get things opened up.

The shutters themselves move freely. I've been keeping them lubricated and have moved them manually a few times a year hoping to get them working at some point.

Seems like I've got everything in place now to get the shutters working again. Probably won't get to it till I start working on the bus in the early spring, but it's nice to be able to find all the parts and supplies needed.

For those curious as to why? Simple, because I can.

[chessie4905]

I have the hydraulic torus fan on mine. Previous owner had it on full setting without the Vernatherm. I found a new one, so going to change back and also  go to air cooled transmission lube.

[lostagain]

When I was driving buses in the 70s and 80s, it got quite cold in the winter, like -30s and 40s at times. All buses then had radiator shutters. It helped warming up the engine faster in the mornings. Also, I remember overnights at hotels with sports teams where we would park at the back of the lot and let them idle all night. So of course the shutters were a good thing. Since the nineties, most buses and trucks have Webasto diesel coolant heaters that preheat the engine and keep it at operating temperatures in cold weather. So shutters aren't seen in modern vehicles much any more.

I understand your desire to fix what you have and keep your bus in original condition. But shutters aren't really necessary in bus nut use. Unless you think you'll be in -30 weather regularly. Without them, the engine will get up to 180 deg. if you put a load on it, like going down the highway. It will run cold only if you idle, or while putsing around town. They weigh hundreds of pounds. Getting rid of them is more beneficial in my opinion.

Your bus, your way. Have fun. 

[luvrbus]

The newer stuff since the 90;s have 2 and 3 speed fan clutches too,the fan draws a lot of HP from a engine ,Mine is hydraulic and will suck some air when on high with the AC running.I have a set of shutters from a MCI if anyone wants a set 

[richard5933]

...I understand your desire to fix what you have and keep your bus in original condition. But shutters aren't really necessary in bus nut use. Unless you think you'll be in -30 weather regularly. Without them, the engine will get up to 180 deg. if you put a load on it, like going down the highway. It will run cold only if you idle, or while putsing around town. They weigh hundreds of pounds. Getting rid of them is more beneficial in my opinion.

Your bus, your way. Have fun.

You're correct, sort of, in saying that they are not necessary. Correct in that most of us will not really notice them if they're missing. But they do have a purpose even for us.

I'm learning that the shutters help with fuel efficiency as well as engine temp, as it takes less HP from the engine to spin the fan with the shutters closed as it does with them open and able to pull air through. During spring and fall weather, when temps are in the 30s - 50s, our engine will struggle to stay at operating temp even while going down the road. Might take 15-20 minutes before we reach close to operating temp, and there are many times the temp gauge reads below 180 even longer. Our gauge indicates a few degrees above actual engine temp so I don't think it's a bad gauge. This means that the shutters should be closed for a decent chunk of time in those seasons.

The shutters on my bus are not that heavy. I've had the entire assembly off and can easily carry it with one hand, so it can't be all that much weight. Even if you add the associated hardware I'd guess it's all under 50 pounds.

More important to me, they're on the bus which means they should be operating properly. I know that there are other methods of accomplishing the same thing on newer buses and trucks, but that's not what I'm working with. I like the challenge in keeping these things working.

[luvrbus]

Bus owners never see the conditions like the buses did designed for revenue service,Me I never owned a bus with shutters before,I know a fan on a GM bus can rob 40 HP that a 8v71 N/A really doesn't have to give up so anything would help   

[richard5933]

Never did learn much about fluid dynamics, especially in relationship to fan design. But, after being told that closing the shutters on a bus radiator results in lower HP demand from the fan, I did some reading. Much more complicated that I thought, but the premise does seem to be valid. Closing the shutters reduces the HP load from the fan, meaning that more HP is available for moving the bus.

[luvrbus]

Fan clutches do the same that is why they are used now instead of the shutters,a good 3 speed fan clutch can cost you upwards of $2000.00 though 

[sledhead]

I fixed my shutters so they worked on the M C I and when it was cold they worked good to heat up the temp. and hold it

On the featherlite when I first got it the fan was on high all the time and it took a long long time to warm up so I put a switch at the dash so now it is always on low unless I turn it on high from the driver seat . now it warms up faster and almost all the time the fan is on low . plus now my fuel mileage is 1-1.5 mpg better and this is going off the cat computer all time average  . win win

so I agree fix the shutters if you travel in cold temps.

dave

[luvrbus]

I fixed my shutters so they worked on the M C I and when it was cold they worked good to heat up the temp. and hold it

On the featherlite when I first got it the fan was on high all the time and it took a long long time to warm up so I put a switch at the dash so now it is always on low unless I turn it on high from the driver seat . now it warms up faster and almost all the time the fan is on low . plus now my fuel mileage is 1-1.5 mpg better and this is going off the cat computer all time average  . win win 

That is very unusual a fan on high all the time on the 3406 CAT they come on high around 205*high is the default speed   

so I agree fix the shutters if you travel in cold temps.

dave

[sledhead]

for what ever reason some one turned it on high all the time in the cat computer ? and I watch the computer as I drive and it has never gone as high as 205 since I have owned it . now if I look at the dash temp. gauge it goes higher the longer you drive and at first it would scare the crap out of me but now that I know the dash gauge is wacked I look at the engine computer to see the temp . and all the rest it shows

dave













dave