Hi guys need help if possible. I have a 4106 that i am servicing to get ready for travel. Years ago the fan clutch drive control module.. this is the device that connects to the bottom of the engine and as best as I can understand, it controls the oil thermostatically from the engine to the fluid drive fan clutch so it will engage and disengage depending on oil temp. There are a lot of spare parts for this bus and I have been just about through everything looking for it. This is the only thing I have found that could be close (See pic) but it looks like it is a directional valve for something because of the arrow on the body. Can anyone supply a picture of what this module looks like along with a diagram on how it's should be run? Thanks
This should help.
Your picture does look like what is in the manual.
Thanks Richard it does doesn't it. I'll check it out tomorrow. I was trying to find it and get it reinstalled before I put the radiator back in. Much easier to get to.
Called a vernatherm. They can be bypassed and fan will run full speed all the time.
Thanks much! Yes that is why it was removed at the time. The clutch was rebuilt just before it went into storage so my thought was to put it back to the original Configuration. I wonder if there would be any Real fuel saving to consider by doing this?
The fuel savings vs the reliability is why most lock the fan in full operation all the time. Yes there is some fuel savings, but in my book, not worth it. My 8 blade aluminum fan on my V-drive is running all the time direct drive geared-allows for running a right hand fan. Good luck, TomC
Thanks Tom decided to leave it locked for continued cooling. Stay safe
Yes, but Toms got the horsepower jacked way up. He needs the heat reduction a lot more than yours. You will probably be running cold in cool weather unless you have shutters.
No shutters. I still have work to do before I turn the key as we live in the south so I still have time to rethink this.
B
If I understand how the venatherm thing works it closes when hot which lets the fan torus fill up with oil. If I have that correct then a bypass valve in line with the venatherm line would provided a manual override in case of problems.
I had an old brochure on Cadillacs vernatherms which showed a model with an air connection port at the nipple end. Apparently an air controlled line connected there to do that.
Dont know if GM ever used them on city busses and have been unable to verify. Never seen them for sale anywhere, even on Ebay. So, I guess using an electrically controlled oil valve should work. Only thought would whether there would be any shock to torus when activating at full goverened speed. Maybe not an issue.
My question is on the arrow of direction on the block. I assume the flow direction is from the engine block to the clutch? And then internally it bleeds back into the block or oil sump? Guessing on this one once the water cools down which closes the flow of oil.
As for connection points, I will take a picture to see if you guys can help me confirm this is where it should be connected. I'll get this sometime towards the end of the week.
Thanks and stay safe
B
My question is on the arrow of direction on the block. I assume the flow direction is from the engine block to the clutch? And then internally it bleeds back into the block or oil sump? Guessing on this one once the water cools down which closes the flow of oil. This is also what fortyniner stated so it sounds correct.
As for connection points, I will take a picture to see if you guys can help me confirm this is where it should be connected. I'll get this sometime towards the end of the week.
Thanks and stay safe
B
From the manual it sounds like it's the other way around - the oil flows from the block to the torus drive, and the valve controls the flow out of the torus drive back to the engine.
Here's the piece from the manual: A fluid control valve (Fig. 11) is mounted in water return between radiator and engine water pump. Purpose of valve is to control flow of oil from torus housing. When temperature of water is such that cooling is required, the valve starts to close, thus flow of oil from torus is restricted. Speed of fan is variable depending upon the amount of oil being retained in to1·us.
Got it and thanks!
If it helps any, that torus should function in a similar way to any other fluid filled clutch... like a torque converter for instance. In which case it will only work if it has oil, because the oil transfers drive from the input to the output.
Jim
Thats right. Exhaust is blocked to cause fan to run full speed instead of temp modulated.
I am much smarter on this then when I began and I appreciate everyone's help!
Correction. Keyser or Kysor of Cadillac made the vernatherms. The manual shoes correct orientation.
Quote from: chessie4905 on January 27, 2021, 11:19:24 AM
Correction. Keyser or Kysor of Cadillac made the vernatherms. The manual shoes correct orientation.
Makes sense - Kysor made the Shutterstat as well.
On our 4106, I blocked off both ends and disabled the vernatherm. I have a 9 bladed plastic fan on ours and it made the engine run cooler but took a bite out of the fuel "economy". So I put the line back in the system and think about controlling the flow with a 12VDC valve. Tha is way down the list of things to do as long as it is not running hot.
@ Friday1
I was glad to see you say it & wanted to note it. Seems like lots of especially vintage bus owners go for lighter weight fans (plastic) and some mention the word "efficiency. IMO efficiency is an obscure word to use about a fan. The more air a fan pushes the efficiency pertains to the cooling it does but as far as taxed HP - more air is more work! If not, what am I missing here?
You CAN improve the efficiency of the shroud without penalty,, in many cases a needed improvement.>>>Dan
Quote from: dtcerrato on February 03, 2021, 07:28:41 AM
@ Friday1
I was glad to see you say it & wanted to note it. Seems like lots of especially vintage bus owners go for lighter weight fans (plastic) and some mention the word "efficiency. IMO efficiency is an obscure word to use about a fan. The more air a fan pushes the efficiency pertains to the cooling it does but as far as taxed HP - more air is more work! If not, what am I missing here?
You are correct. I changed my fan because the original looked like a propeller from a B-17 after a landing without landing gear extended. With that much weight way out of balance, it had to be much less efficient. It takes a lot of horsepower to spin the fan fast and pull a lot of air through the radiator. Another trade off you have to weigh any benefit to see if it is worth the expense and if your original goals are met.
Quote from: Utahclaimjumper on February 03, 2021, 08:04:20 AM
You CAN improve the efficiency of the shroud without penalty,, in many cases a needed improvement.>>>Dan
Good point. My next metal project is to make the shroud work better and look into making the belly pans.
Make sure you have the full width flap right behind rear axle attached to bottom of bulkhead.
Quote from: Friday1 on February 03, 2021, 11:53:27 AM
Good point. My next metal project is to make the shroud work better and look into making the belly pans.
I've thought that the belly pans do a lot for improving air flow through the radiator. The ones on my bus have rearward-facing louvers which should create a negative pressure pulling air out of the engine compartment, and since the radiator door is the only real opening for air to enter it's got to increase air flow through the radiator as long as the bus is in motion.
Quote from: richard5933 on February 03, 2021, 04:35:55 PM
I've thought that the belly pans do a lot for improving air flow through the radiator. The ones on my bus have rearward-facing louvers which should create a negative pressure pulling air out of the engine compartment, and since the radiator door is the only real opening for air to enter it's got to increase air flow through the radiator as long as the bus is in motion.
Richard, Are your belly pans OEM or you made them. I would like to know any info about them. What thickness are they? Thanks in advance
Quote from: Friday1 on February 03, 2021, 08:24:06 PM
Richard, Are your belly pans OEM or you made them. I would like to know any info about them. What thickness are they? Thanks in advance
Definitely OEM. Not sure of the thickness, but IIRC about the same as the other non-structural panels around the bus. I'll try and measure next time it's not snowing/icing outside and get back to you.
There are two pieces for mine on the 4108 - one main piece under the bulk of the engine and another smaller one driver's side under the radiator. There are a few u-channels running front to back to stiffen the belly pans, and they are both louvered over most of their surface with rearward-facing louvers. These are key, IMO, to making the belly pans do their job of sucking air down and out.
This photo is taken through the curb side transmission door looking at the main belly pan. You can see a couple of the spring-loaded mounting points from above and the circular depressed area built into the pans where they mount. I believe that these circular depressions are just tack welded into holes. You can see the spring end of the mounting points above the cradle, and down below they have about 1" diameter loops sticking down. These loops rotate and go into slots in the pans to lock them in.
Where each of the mounting points are there is about a 3" diameter depressed area where the spring-loaded mounting loop goes, resulting in the belly pan being about 2" offset from the mounting points. The OEM mounting loops go through slots in the belly pans and then turn 90 degrees to hold the pans in place. If you are making the pans from scratch and don't have mounting points, it would probably be possible to use some type of stand-off spacer and mounting bolts instead, but whatever system you create for mounting should enable you to remount the pans easily. You'll be holding them in place with one hand while fastening them in place, so simple is better. If I didn't have the OEM spring mounted loops I'd probably consider tacking 1" studs under the cradle which the pans could be raised onto, then you'd only have to put on some wing nuts to fasten. Hopefully you still have the OEM mounting loops.
they use the same loops below ac condenser
I am not a GM bus guy at all, but, in MCIs, in my learned opinion (ha, ha !), the belly pans under the engine were there to keep the gravel and road grime out of the engine bay. They were louvered as well. I think the air out of the radiators flows out the bottom easier without them. I removed mine out of the MC5 and I think it runs cooler without them.
Without the belly pans there is going to be a lot of turbulence in the engine bay. The air coming in through the radiator has to go somewhere, and if there is turbulence in the engine bay the route down and out is not clean.
The louvered belly pans create a negative pressure area as the airflow goes over the outside of the louvers, effectively pulling the air out.
A similar situation which demonstrates this is the vent tube on our waste water tank. It goes down and exits through the floor of the bay. When I first got the bus the bottom of this vent tube was cut straight across, and as we drove down the road air was pushed up through the tube resulting in foul odor inside the bus. I cut the bottom of the tube at an angle, creating a situation similar to what the louvers do on the belly pans, and now as we go down the road there is a negative pressure created pulling the foul odor out instead of forcing it up into the bus.
Quote from: richard5933 on February 04, 2021, 08:22:06 AM
Without the belly pans there is going to be a lot of turbulence in the engine bay. The air coming in through the radiator has to go somewhere, and if there is turbulence in the engine bay the route down and out is not clean.
The louvered belly pans create a negative pressure area as the airflow goes over the outside of the louvers, effectively pulling the air out.
A similar situation which demonstrates this is the vent tube on our waste water tank. It goes down and exits through the floor of the bay. When I first got the bus the bottom of this vent tube was cut straight across, and as we drove down the road air was pushed up through the tube resulting in foul odor inside the bus. I cut the bottom of the tube at an angle, creating a situation similar to what the louvers do on the belly pans, and now as we go down the road there is a negative pressure created pulling the foul odor out instead of forcing it up into the bus.
Richard, I have two 17" SPAL fans mounted in my rear engine door to expel the engine heat so the bedroom is not like an oven after a day of driving. The fans are controlled manually. I have several of the original spring fasteners still below my engine. The PO had a frame welded in the back to tow his toad and I think some of the original springs are gone. Mainly I want to keep my engine clean and sanitary. I also have a design for a "tail" on the edge of the roof to break the vacuum and keep the oil freckles at a minimum. I am talking a tail like on a racecar that is over the drag chute also to break the vacuum. Free horsepower? With the flat rear end of the body there is a lot of turbulence back there.
(//)This was just after installing the fans. I built an awning over them to keep the rain out later.
Richard, I have two 17" SPAL fans mounted in my rear engine door to expel the engine heat so the bedroom is not like an oven after a day of driving. The fans are controlled manually. I have several of the original spring fasteners still below my engine. The PO had a frame welded in the back to tow his toad and I think some of the original springs are gone. Mainly I want to keep my engine clean and sanitary. I also have a design for a "tail" on the edge of the roof to break the vacuum and keep the oil freckles at a minimum. I am talking a tail like on a racecar that is over the drag chute also to break the vacuum. Free horsepower? With the flat rear end of the body there is a lot of turbulence back there.
[/quote]
If you're looking to keep the engine clean, then that rubber guard just behind the rear axle hanging down from the bulkhead would be important. The belly pans will help, but make sure they are louvered. Those fans will help when you're parked, but they won't be able to keep up with the amount of air coming in through the radiator.
For the deflector to keep the back of the bus clean, check out what they install on school buses. May not be necessary to reinvent the wheel on this one, as there are many options to choose from. If nothing else, you can copy their designs. Most I see have two layers.
https://www.seeiiairfoils.com/uploads/Slide-1.jpg
I have the rubber flap at the bulkhead. I only run the fans after running hard and then in slow traffic or when I am stopped for a while to draw the heat out of the engine compartment. There is a lot of heat that comes out of that rear door with the fans on. I see the rear wing and that might work good. I had something different in mind and will send a pic when I find one.
(//) This is what I have in mind. The wing will bend around the bus roofline at the ends. I'm thinking if I extend it 18" it will work to break the turbulence and make it more stable driving.
I seriously doubt you'll feel a bit of difference in the way the bus handles going down the road. That wing is really huge in relation to the size of the vehicle, but on the bus it would have negligible effect. If I remember correctly, there was a slight amount of that shape to the rear of your bus from the factory - I know there is on my 4108.
To keep the rear of the bus clean you're going to have to create a pretty sharp downward air flow. That's why the school buses use one shaped like I posted earlier. When I was a kid and my dad had a huge station wagon, it had a wing on the rear like the school bus wings. The only purpose was to deflect air down and across the rear window to prevent it from gathering road debris and wheel spray. This was before rear window wipers, and it seems to me that it made a difference from the one we had before without the wing.
Lots of oil and other splatter is going to come up from the exhaust and engine drippings, and having the positive downward airflow might help.
Of course, realize that anything you do to the airflow around/over the bus could have negative consequences in other systems. Would really suck if you obtained a clean bus rear end at the cost of starving the radiator of air flow somehow. Not saying it would do that, but all the air flow around/over a bus is interconnected and what you do in one area does affect others.
Friday -
Before you start messing with a wing on the rear roof of your '06, perhaps you should take a look at some other ways of reducing the oil splatter first:
1) Fix any oil leaks you've got.
2) Use a "catch can" for the air box drains.
3) Extend the tailpipe slightly beyond the bumper, and include a downward facing tip.
4) If a PO installed one of those "skirts" that hangs off the rear bumper, remove it.
5) Run the rack on the engine to make sure all the injectors are set correctly.
Glad to hear that you've got the full-width "mud flap" at the bulkhead - that alone creates a huge low pressure area under the engine compartment, helping to draw out the hot air. Folks that remove that flap have no clue as to it's purpose.
FWIW & HTH. . . ;)
clean engine and work on the leaks. using catch can will help a lot if you dont already have one. Rear spoiler has been done and not the cure all expected.
I replaced the fan hub seals and bearing. Removed the shaft that used to drive the AC compressor and made a plug to fit in there where the pinion was and sealed it all up. However the fan seal has started to seep again and it is probably getting strewn around by the fan. I have a catch can. Have not run the rack. I sent a dozen emails to BGM, Scott and never got a reply trying to get on his schedule for that service. I had five surgeries close together and still recovering from that so projects I start have to have a likely chance of completion so someone else won't have to finish something I start. I don't have a skirt at the rear bumper and I do have a downward facing tailpipe extension facing toward the ground. The freckles are not that bad but I know they are there. When I wash the back, I spray a little Simple Green on the rear and they come off easily.
Quote from: Friday1 on February 07, 2021, 12:48:07 PM
I sent a dozen emails to BGM Scott, and never got a reply trying to get on his schedule for that service.
Friday -There are other technicians scattered around the country who can run the rack on your Detroit besides Scott.
If you'll take a couple minutes to edit your profile to include your coach's VIN and your home-based city and state (similar to mine at the bottom of this post), then perhaps we can better assist you in providing nearby help.
FWIW & HTH. . . ;)
Are you still in the Toledo area? If so, there appear to be a lot of heavy truck and bus shops in your area. Have you tried any of the local Detroit Diesel shops to see if they have a 2-stroke trained tech on staff?
Quote from: Friday1 on February 07, 2021, 12:48:07 PM
I replaced the fan hub seals and bearing. Removed the shaft that used to drive the AC compressor and made a plug to fit in there where the pinion was and sealed it all up. However the fan seal has started to seep again and it is probably getting strewn around by the fan. I have a catch can. Have not run the rack. I sent a dozen emails to BGM, Scott and never got a reply trying to get on his schedule for that service. I had five surgeries close together and still recovering from that so projects I start have to have a likely chance of completion so someone else won't have to finish something I start. I don't have a skirt at the rear bumper and I do have a downward facing tailpipe extension facing toward the ground. The freckles are not that bad but I know they are there. When I wash the back, I spray a little Simple Green on the rear and they come off easily.
A rack setting has nothing to do with spotting,if the engine starts and runs good leave it alone the old Detroits get into their comfort zone and DD has no schedule for tuneups .Check and see if you have a check on the lower head for the air box drain if so clean it if not install one,Jake brakes will cause one to spot more also, sounds to me like you don't have much of a problem rfepair what leaks you can find Detroit's can be leak free
Quote from: richard5933 on February 08, 2021, 03:54:34 AM
Are you still in the Toledo area? If so, there appear to be a lot of heavy truck and bus shops in your area. Have you tried any of the local Detroit Diesel shops to see if they have a 2-stroke trained tech on staff?
I was a mechanic for the Toledo Fire Division for 30 years. I know some of the techs at Williams but was wanting someone that knew about conversion buses and would give me a break on the labor if I helped. My engine has about 65K on it since it was installed-a crate motor due to the PO not paying attention to the water temp in the mountains. I put an ISSPRO water temp with 270 degree sweep needle and a warning light at 205F. I have a custom dash with ISSPRO instruments and warning lights for low water, low oil, high temp and No charge. When we raced the dragbike it had 13 readouts of computer data to look at after each pass. The passes were high 7 seconds and low 8's so you couldn't depend on the rider's @$# dyno to tell you what just happened. Info, data keep you out of trouble. When I retired the new fire trucks were just getting into "multiplexing" and all the info displayed on the pump panel where the pump operator stood and controlled the pump came down four wires. I didn't have much to do with that. I prefer mechanical instruments but in the case of water temp they don't make any with 40' Burdon tubes. ISSPRO guaranteed me accuracy to less than 2% on my instruments so I guess that is tolerable. Thanks for reminding me to fill out my info. Check out my avatar.
Did the fire equipment still run 2-strokes when you were there? Maybe there's someone else from the dept. that can lend you a hand running the rack.
In 2002 I helped write specs for 6 Peterbilt based pumpers with Cummins power. That was the end of Detroit diesel except for Series 60's in some of the million dollar ladder trucks. Two stroke Detroits did us well. We had some late 1940's pumpers and ladder trucks with 6/71's and an old FWD that were repowered from Waukashaw or Continental gas engines. You know, vehicles with real fenders! All the old pumpers were custom built Peter Pirsch, Seagraves, Sutphen, or American LaFrance so they had gas power rear axle ratios. After the diesel engines were installed, one would spin the dual rear tires but top out at 35 mph. So they put a real tall gear in the next one and it would go 75 mph. That was when there were 11 firemen doing the repairs. That group only had 3 men who were really mechanics and the other 8 were sent there as punishment and that meant they were on an 8 hour day. Line firemen worked 24 on 48 off and one tour of duty off each month. So when real mechanics came over to repair the terrible fleet it was a struggle-"We never replace any drums or discs, that cost too much. Just put a set of pads and shoes on and get it back out there." It took us 3 mechanics about 3 years to have the fleet standing tall and the admin cried the whole time that maintenance cost was never this high. Yeah, everything was held together with tape and bailing wire. Now they lease pumpers from a couple of outfits. Nobody working there now is a Detroit guy. I could do the easy half of the rack if I had someone coaching me. I doubt if I could do the inside half due to 2 back surgeries has made me not very bendy anymore.
Friday -
I found and scanned a GM Service Bulletin about the Torus drive for the engine cooling fan. I've attached it to this post for you, hopefully it will answer some questions.
On another topic, PD4106-326, if you don't know already, was delivered new in March of 1961 as fleet number S-654 to Safeway Trails, HQ'd in Washington, DC. Safeway was, and I think still is, a Trailways affiliate carrier.
FWIW & HTH. . . ;)
Thanks so much for the PDF. Great info to have. I removed numbers 38-53 the pinion and everything that made up the drive for the AC system. I made an aluminum plug and installed it in place of that. My cooling system is working great. I had to have the radiator recored and all new hoses when I got home from picking it up in Phoenix. The PO was very honest and told me the radiator was bad...... after I got there to inspect the bus. I gulped hard and got in the driver seat and said a little prayer for the radiator and took off.[/img] When I blocked off my Toros drive oil to make the fan run all the time, the fuel mileage dropped. The plastic fan has 9 blades vs 8 blades on the OEM fan. It moves a lot of air.