First off let me introduce myself. I'm WillyT. I am new to the group and this is my first post.
I have owned my 1993 28' Georgie Boy class A on a P30 frame for 3 years now. I have completed many repairs and upgrades to "Maureen". And she's very happy for it.
I apologize for the length of this post. But felt, since I'm new to the forum, I should give some background.
Our current project is addressing the hot running/ over heating problems of the Chevy 454.
I had the original radiator rebuilt last spring. Reinstalled it with new fan clutch and original fan shroud. On our 2nd trip of the summer, on a climb up a long hill. She pulled the fan shroud loose from the bottom clips. sucked it into the fan and destroyed the shroud. Luckily the radiator received no damage.
I've looked high and low for a new shroud. I have found nothing. I even tried to get one made. But as soon as anyone that could make one heard it was for an older motorhome.... they didn't want anything to do with it.
So I committed to converting to electric fans. And the project is going well.
Until now.... Here's the problem:
I need to install the temperature switch in the cylinder head to activate the fans at the appropriate time/ temp. On the passenger side is the temp sensor for the computer. This, as far as I know is not an option. On the driver's side the temp sender is for the gauge on the dashboard. That's real important information that I monitor constantly while driving.
So here's the question:
What do I do now? Where can I install this temperature switch and still maintain a working gauges? What am I missing here?
You are making an add-on to the RV that originally wasn't designed for this.
If there is no place to attach the sensor to the cylinder head there is no other way to make a place yourself. So drill a hole, tap a threath in the hole so you can screw the sensor in.
This said, you really need to know what you are doing so expert advice for this is needed. As far as I understand there still are specialist or classic car shops in the USA that can do this for you.
As for reproducing an object that is discontinued, have you tried a 3d printer shop? I saw it once in episode 152 of Wheeler Dealers where Mike and Ant restored a 1976 Ford Capri. there was a plastic (discontinued) part of the sunroof broken which was a common known problem and they had it reprinted and fix the problem.
Wheeler Dealers Series 15 (2018/2019 episode 152 (https://en.wikipedia.org/wiki/List_of_Wheeler_Dealers_episodes#Series_15_(2018%E2%80%932019))
Personally, I would think long and hard before drilling and tapping into an 'in place' head. You would create a fair amount of shavings as well as hoping to hit a water jacket. Is it possible to source a T or Y fitting for the dash sensor? Or to tie the fan switch wiring into the gauge wiring? If the fan manufacturer has a customer support service they may be able to advise you. Another alternative is to wire the fan switch to a dash switch that you can turn on and off as required by monitoring your dash temperature gauge.
Unless you run a machine shop I'd stay away from such matters, there are plenty of tap points in the block/intake..Aside from that heads run quite a bit hotter than what you might think.
The 93 P-30 chassis should have (3) sensors
1. Passenger side near head (this turns on the auxiliary fan)
2. Drivers side near head (dash temp gauge)
3. Front side of intake manifold below the bypass hose. (This is for the ECM)
If you wire it into the passenger side sensor it is designed to kick on at approximately 221F
I've glued a Bi-Metallic switch to the thermostat housing. Just clean it really good - and use high temp epoxy. I've strapped the switch down with a ZipTie and let the epoxy cure for 48 hrs - still there a decade or so later.
(https://images-na.ssl-images-amazon.com/images/I/41FMBvxhhwL.jpg)
that switch runs to a relay which then starts the Fan. Pretty simple, nothing to cut, no change to the original system. I've wired the fan directly from the fuse Terminal
I did that like 15 years ago, so don't ask me what temperature switch I used i??
Downside of my configuration is - the fan keeps running as long the engine is hot. So you turn the engine off - the fan keeps blowing - not very long usually 2-5 minutes.
I kept it, because I believe that reduces the heat soak after shut off.
One more thing, I've added a deflector plate under the hood - between fiberglass front nose and the upper radiator support - so all air going to the grill is forced into the radiator. It can not escape up and above the engine anymore.
That reduced the times my radiator fan start 2/3s as long as I'm driving.
(https://scontent-atl3-1.xx.fbcdn.net/v/t39.30808-6/240828138_10216423393897680_1794812669756560091_n.jpg?_nc_cat=106&ccb=1-7&_nc_sid=b9115d&_nc_ohc=VxgCKg3wt4wAX_0TDM8&_nc_ht=scontent-atl3-1.xx&oh=00_AT9RruR9iKJPoRuyzAifKAdte85HKQsGoDHf8hJrsXuhNg&oe=63072DBD)
(https://scontent-atl3-1.xx.fbcdn.net/v/t39.30808-6/240834019_10216423394177687_8370225007049755839_n.jpg?_nc_cat=110&ccb=1-7&_nc_sid=b9115d&_nc_ohc=HqqK1GLmLIMAX_4uTLs&_nc_ht=scontent-atl3-1.xx&oh=00_AT_y4n31-Ku3ZH6d2UOqPDvxJnenBwLnf4j1bF6-tWwUTA&oe=6307189D)
(https://scontent-atl3-1.xx.fbcdn.net/v/t39.30808-6/240876961_10216423394537696_1911116108503764359_n.jpg?_nc_cat=108&ccb=1-7&_nc_sid=b9115d&_nc_ohc=kt9_30ERhYcAX-vOFnn&_nc_ht=scontent-atl3-1.xx&oh=00_AT9xrK0uzmLX3ZBGkE_WQ1-y28A2aMd728fjabvpLbZQYQ&oe=6307F534)
1/2 Polyiso insulation board
Quote from: eXodus on August 21, 2022, 09:35 AM
I've glued a Bi-Metallic switch to the thermostat housing. Just clean it really good - and use high temp epoxy. I've strapped the switch down with a ZipTie and let the epoxy cure for 48 hrs - still there...
Nice mod! I agree, I think the downside is really a plus. Cars for quite some time have had fans which continue to run after shut off for the reason you stated.
Thanks everyone for the replies. There is some really good advise and ideas here.
In the time that passed waiting to be approved as a member. I did some digging on my own. Attended a few 'Youtube University' classes on the subject. And decided to try an insert in the upper radiator hose with a cooler than called for switch (180 on 165 off). The complete install is almost done.
I'll let everyone know how it turns out.
And hopefully add to the collective knowledge of the group.
Whatever you do do not replace the OEM T stat (195F) with one that is cooler. The engine will run richer as a result and lower your MPGs.
Will be interested for pictures of the electric fan setup.
Which fans did you get?
Yeah don't change the hydraulic Thermostat. Those 454 are happy at up 230F.
195 is the lowest Thermostat I would run.. otherwise fuel mileage will suffer.
I think my 1996 454 came with a 205 or 210 Thermostat.
OK, today was the 1st test run. It's 100 deg out so was a good time to test.
Every thing worked as it should. But I would like the fans to kick on a bout 20 deg sooner so I ordered a cooler thermo switch. But I had installed a bypass switch mounted on the dash, just in case.
And I think the install looks pretty good, if I do say so myself.
BUT, it does not do the job. Motor overheated before I got out of town. I feel like it's not moving enough air. Maybe even less than originally. Like maybe when the plastic fan blades got hot they flattened out.
Pretty frustrated right now. But I'll get past that. Just gotta keep working the problem.
Just FYI the fan/ Shroud is the ALLOYWORKS Aluminum Radiator Shroud+2x12" Fan bought off amazon. But the fans appear to be standard with all suppliers.
Thought?
I put my fan in front of the rad. I'm pushing cold air into and threw the rad.
The 90s P30 had a Fan in front of the Radiator pushing in addition to the mechanical fan in the back pulling.
12 inch fan doesn't really tell us very much. They make 12 inch fans between 600 CFM and 1750 CFM
You should be looking to get at least 3000 CFM total for a 454.
When I converted mine more then a decade ago - I used the original Fan shroud and installed a single large electric fan from the Junkyard.
Not sure the donor - I think it was a Volvo ;)
So you got options here:
1. Add another fan in front of the Radiator
2. Switch out those fans with higher flowing ones
3. Remove the whole thing and get a single large one
Gentlemen,
First off, thanks for taking an interest in this project. I need someone who gets what I'm trying to do. Has some experience with the same type of project. So thank you.
Are my pics being posted? I'm not seeing them. I posted several pics of the cooling project so far. But.....
After an afternoon of looking, the only CFM info I could find on the fans I have is that they are 1750 cfm (info from Amazon). But I'm doubtful of that number. And I think they are not moving as much air as they did when I tested them before starting the engine and getting it warm or hot as the case may be.
I think I'm gonna try 2x 14" 1900 CFM fans. That's 3800 CFM total. Should be enough. And at a 9.5 amp draw no rewiring will be involved.
The single 16" fan will move up to 3000 cfm. But with a radiator core measuring 20x33 one wont cover much of the radiator.
But I can't shake the feeling I'm missing something.
Sure, happy to help.
Yeah getting something larger single in the aftermarket is difficult. I think the opening for the mechanical fan is about 19-20 inches.
You have the old fan blade probably laying around somewhere. Measure and see how much real opening the old fan had. Radiator size doesn't really matter.
That's why I used a Electric Car Radiator fan back then- it fitted the original Fan Shroud perfectly.
https://www.etrailer.com/dept-pg-Radiator_Fans.aspx
Little pricy but lots of options.- I think the Junkyard fan I used was like $20. With inflation probably $50 by now lol
another idea - how much gap do you have between the radiator and that aluminum piece?
You need to have some decent clearance - otherwise the fans are only pulling air directly behind them and not through the whole radiator.
To be honest, I personally think it's best not to trust on Amazon or similar online shops when it goes about items as important as your radiator fan, even more so when it will becone your main fan.
Amazon is a shop which assortment exists mainly out of China junk as your radiator fans or products where you are way better off buying from the supplier directly, because of pricing, warrenties etc. I will admit that China junk does look cool, it's shiny, and hey, it's cheap. But time after time the China junk proves not to be what it promisses, so people buy the next China junk product because they don't want to pay for a quality product that will work for years to come because they are often way overpriced. I learned my lessons the hard way however so NEVER China junk for me again if I can help it and I'm just trying to save you the agony and frustration.
I just can't get it that your engine is a chevy 454, one of the most comon engines in the USA, and that there isn't a fan shroud out there anymore. Is the set up for a GeorgieBoy really that different because hust by typing Chevy 454 fan shroud, I get this:
https://www.summitracing.com/search/part-type/fan-shrouds/make/chevrolet/engine-size/7-4l-454/fan-shroud-material/plastic
But Exodus gave you some really excellent tips so maybe you have enough to go on allready.
Mlw,
Thanks for the advice and the link.
You are right about Amazon and Chinese crap. And I'm learning much on this journey. I'm looking at electric fans at Summit Racing already.
I've looked a lot for a shroud for the mechanical fan. But even summit doesn't give enough info such as dimensions of the shroud to be sure it is the right one. Or at least close. And filtering to 1993 Chevy P30 always ends in a 'Not Available' response. In this application the radiator is off set to the drivers side quite a bit. and the shroud reflects that in it's shape. And the radiator is HUGE the core measures 20.5" high and 33.5" wide.
So these are other reasons why I've gone down this electric fan road.
But again, thanks for your response. And I'll take your advice about amazon junk. At least when it comes to auto parts.
Yep, I had the clearance issue thought as well. That's why I'm gonna try 2X 14" or maybe 2X 16" (if they'll fit) fans mounted directly to the radiator core. And abandon the Amazon crap.
If this does not work I've got another problem. But I know the thermostat is good I replaced it last year. And the upper hose pressurizes at the right time. And the pump is new as of a year ago as well. and 1000 miles or so.
The P30 chassis had the radiator mount included - so all 454 from similar years should have the same fan shroud.
Probably everything from 1980s to 1995ish 454 should have the close matching parts. Sometime in 1996 the 454 became the 7.4L Vortec and got a new fan blade and shroud. Might still fit, but probably more changes.
I am taking your suggestions and researching. The early 90' Chevy 1500 shroud looks very close. But no matter how hard I look I can't seem to find dimensions. If I could get measurements it would help a lot. But I just don't know. So I ordered 2x 16" fans to mount directly to the radiator core. Ordered from Summit Racing.
If I was an engineer I'd have gotten this right the first time (maybe). But I'm not. So trial and error is the only route. Not my first journey down the TnE road.
But, I find it engaging, entertaining and rewarding when a project is done and working correctly. And I suppose that translates to fun?
And I appreciate you all coming along for the ride. You're all a great help.
The pics are of the original shroud. It is held together with clamps because it is in 5 broken pieces. And a rough drawing I made of it to give some dimensions.
I got you on the trial and error due to lack of expertise. Finding direct, bolt in changes can be nearly or totally impossiblel. The upside is that "close" is often the cure with some creative modification.
Your fans will not function correctly without a cowl,never use a fan blade that is waffled or irregular, I can hardly believe such fan blades are made. Google super cavitation...I cannot even believe experts would question why cowls use energy..Cowls focus large amounts of air..large amounts to a confined space or area. Pressurized!
https://youtu.be/Os_Hna9DZa8
pressurize verb
Save Word
To save this word, you'll need to log in.
Log In
pres·sur·ize | \ ˈpre-shə-ˌrīz \
pressurized; pressurizing
Definition of pressurize
transitive verb
1: to confine the contents of under a pressure greater than that of the outside atmosphere
especially : to maintain near-normal atmospheric pressure in during high-altitude or spaceflight (as by means of a supercharger)
2: to apply pressure to
But then there is this:
https://www.youtube.com/watch?v=3bSM3fQdmW4
That would be a good starting point, high rake fan blades along with the blade tips very close to the housing. Very efficient moving air or water, they keep cavitation at a minimum. Now you need to pressurize/direct that air flow to the entire surface area of the radiator, just as there are hot spots there are cold spots. It would be interesting to determine how much effective cooling surface of the radiator is left out of the process when a fan is placed in close proximenty to the cooling area. Once a effective cooling system is built then there is amperage draw needed to run that much air displacement. GM long ago setup a system that required about 15/25 hp to cool a engine..somethings just do not change.
As to high rake blades...you can see them and google them..submarines have used them for a very long time.
The above is strictly a opinion your mileage will vary of course.
the old Mechanical Fans are just very inefficient. Fuel was cheap remember.
When you in comparison look at modern GM fan blade:
(https://s3.amazonaws.com/rp-part-images/assets/6a39647a7ca673b2c0b6fa0142a252e0.jpg)
Those draw much less power then the metal things our old RVs got under the hood.
And electric fans are even better - even a high power fan - doesn't draw more then like 40A - which translates 40a x 12V = 480W - so when you got two of those - you are looking at not even 1 kw - which is like 0.8HP - even when assuming the alternator is only 50% efficient - we are always looking at less then 2hp for a electric fan setup.
Lot's of free horses and torque vs the mechanical fan.
Hey Willy,
Well that's why were all on this forum, to discuss and learn from each others mistakes. My mistake was to buy an RV that actually should have been scrapped. However I'm in way to deep to give up now. Let's just hope that it will be worth it in the end.
I also hear you about not getting specific specifications about dimensions etc. Yep, a problem we all have. What I do is look for the price and then ask myself if I mind loosing the money if the product is not right. I have to because I live in the Netherlands and sending a wrong product back would cost me more then ditching the product. But you live in America so you can send the product back for normal delivering fees or even free?. Until now, ordering most parts at Rock Auto who have an excellent specification system if you asked me, the only thing I received wrong was the powersteering belt worth $2.50. Oh, and an exhaust pipe worth $16,=. I made use of a forwarding company, and they wanted to charge me $500,= extra because it was oversized. I don't think i have to say that i ditched the pipe. I think €18.50 loss on orders worth $1500,= isn't bad and the price we have to pay in a world were online shops are taking over.
So as you see you are not alone and we all have our little mishappenings fixing up our RV.
And: as I am the Devils advocate on this topic allready
https://www.youtube.com/watch?v=ZqxwUgFJ6n8
I've bought a viscous clutch for the fan of my Betsy, they also make sure that your fan doesn't turn at the same speed as your engine but just as fast as needed. then follow the tip of exodus and put an electric one in front of the radiator. I have a setup like this in my BMW e39. The fan clutch makes the fan spin but not crazy fast. When the engine gets warm or I turn the AC on the electric fans kick in. And when it really gets hot like this summer than the Viscous coupling goes in "turbo mode" and your hear the fanblade whining. but as far as I know never goes over 2500 RPM and the temp gauge is always in the middle as it should with a BMW, so why shouldn't this work on a Chevy.
It has probably been a couple years since I last posted on here but I happened by and saw this thread and figured I would throw in my two cents. You are not going to find any electric fans from the aftermarket that will cool a 454 motorhome! Will not happen. If you really feel you have to go electric then go to a junkyard and get a fan from a 90's Ford Crown Victoria, preferably an old police car. They move 10 times more than any aftermarket fan and if for some reason the motor goes bad you can get a new one in any parts store anywhere. That said, you will need a full shroud that goes from side to side of the radiator and with all of those coolers in front of the radiator you will need at least two electrics out there also. That was the stock configuration of the 80's-90's motorhomes. You are best suited to replace the fan and fan clutch with the original belt driven parts and find a replacement shroud though. That belt driven fan will move a couple thousand CFM, more than any electric. And it will fit the shroud. That shroud is not in that bad of shape from the pictures. Top and bottom are normally two parts split at the center so it is broken at top center and bottom center right? Aluminum flashing, epoxy and pop rivets will fix it right up but I can pretty much guarantee you could find one in a junkyard out of a pickup or another motorhome. As far as the temp sensor for the fan I usually drill and tap the thermostat housing for a short sensor and put it in there and use one that come on at no more than 200 degrees. I prefer it to come on just above thermostat opening.
Great to see Rick back :)
There are aftermarket electric fans for almost any applications. Even modern Semi trucks come with Electric Fans.
It's not cheap to go electric by any means if you go aftermarket. But like you said - the junkyard can be the solution. They charge a single price per fan
I know it's an old thread but this may help someone out later.
I got rid of at least 50 pounds of weight getting rid of that brass boat anchor radiator, upper/lower mounting brackets,shrouds and fan clutch. Used a 3 row aluminum radiator for the 1999-2012 Sierra,Yukon, Silverado series and the double electric fan setup from any of those vehicles that had the HD towing package. The core is HUGE in width ( 40") compared to the original radiator but it only takes minor fabricating of angle aluminum and a couple of 3x3 box sections 3-4 inches long and no welding. You will be mounting it way further fwd resting on the front frame crossbeam
A 200 degree on/185 off temp switch controls one fan and the second switch is 210/195 for the second fan... it never comes on.
I also can literally poke my head up thru the bottom and change the belt, water pump or access anything on the front of the motor without removing.
Underway the fan never comes on and will maintain 190- 195 and with the fans on manual it will get to 180 where the thermostat keeps it there.
Well worth the hassle of installing and about $500 total in parts- sweat equity not included. You probably cannot even get the brass one repaired under that price plus you can go to any parts store and buy an OEM replacement radiator for $200 out on the road.
Rick is spot on about the fans - the best single fan setup is the 2 speed late 80's - 95 3.8 Ford Taurus/Mercury Sable units and they outperform just about all the aftermarket ones almost like 4600 cfm. It was the only fan that could keep my pro street Vega under 220 in Florida summer stop and go traffic.
Also for those needing another temp sensor location they sell these inline radiator hose temp switch adapters on Amazon, flea bay and Jegs and summit racing
Quote from: Potatochip P30 on March 13, 2023, 01:09 AMI know it's an old thread but this may help someone out later.
I got rid of at least 50 pounds of weight getting rid of that brass boat anchor radiator, upper/lower mounting brackets,shrouds and fan clutch. Used a 3 row aluminum radiator for the 1999-2012 Sierra,Yukon, Silverado series and the double electric fan setup from any of those vehicles that had the HD towing package. The core is HUGE in width ( 40") compared to the original radiator but it only takes minor fabricating of angle aluminum and a couple of 3x3 box sections 3-4 inches long and no welding. You will be mounting it way further fwd resting on the front frame crossbeam
A 200 degree on/185 off temp switch controls one fan and the second switch is 210/195 for the second fan... it never comes on.
I also can literally poke my head up thru the bottom and change the belt, water pump or access anything on the front of the motor without removing.
Underway the fan never comes on and will maintain 190- 195 and with the fans on manual it will get to 180 where the thermostat keeps it there.
Well worth the hassle of installing and about $500 total in parts- sweat equity not included. You probably cannot even get the brass one repaired under that price plus you can go to any parts store and buy an OEM replacement radiator for $200 out on the road.
Rick is spot on about the fans - the best single fan setup is the 2 speed late 80's - 95 3.8 Ford Taurus/Mercury Sable units and they outperform just about all the aftermarket ones almost like 4600 cfm. It was the only fan that could keep my pro street Vega under 220 in Florida summer stop and go traffic.
Now that engine bay has some serious tinkering going on. Perhaps a thread is in order here. Speaking for a friend of course.... :azn:
Nothing crazy just a drop in 8.1 ( 496ci) vortec motor linked to the 4L80 trans.
Had a tick noise on the 454 which ended up being piston slap on no 7 and since I had the trans pulled back, flex plate off, oil pan removed in the search for the noise... an 8.1 kinda just fell in there one night lol.
I really didn't go too crazy taking pics but I will post some in a bit, just have to dumb them down in size to be able to upload here