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Discussion Starter · #1 ·
I've got a 1983 Class A RV with a BBC 454. It's the original engine with at least 75k miles on it and the A/C unit no longer pumps cold air. I'd like to remove the A/C unit all together because I'm not using it and it's just one more component the engine has to turn.

So what's the proper way to remove the A/C system? I'm not so much interested in knowing how to unbolt the unit from it's mount on the engine, but rather which hoses to disconnect/cap and is there anything special I should do or know to accomplish this task?

I've also read somewhere that removing the mechanical fan off the front of the engine and replacing with an electric fan will also lessen the load on the engine. Do you think this is a good idea?

I appreciate any feedback you engine guru's can provide.

Thank you!
 

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Unless your trying to lighten up the rv for some sort of motorhome drag racing class i'd say just remove the belt and forget about it.
 

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Unless your trying to lighten up the rv for some sort of motorhome drag racing class i'd say just remove the belt and forget about it.

i agree with this just cut the belt and forget its there you will just get into enviromental probs. if you looking for weight reduction then your only gonna get about 30 lbs. and yes and electric fan is great as long as you remember to turn the bastard on:)sphss
 

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Discussion Starter · #4 ·
Well....I'm not really looking for weight reduction, but considering my mph....I'll take the 30lbs gain. The real reason I want to get the A/C unit off the engine is for better engine access. My RV's temp gauge spikes up to 3/4 guage on any hill I hit whether I'm towing or not. On flat runs the needle is in the middle of the gauge, and because of her age, I'd like to do anything I can to keep the motor running cool/longer. I've had the RV for 3 years and she runs good and strong....even passed CA smog test after a tune up....and she handles well. I live 7 miles from the Beach and that's where we go most often; but we also hit the dessert with toys in tow each fall/spring and these trips is when the work out really happens. So besides the A/C removal, my list of tasks includes:

thermostat
radiator serviced
water pump
air damn from front bumper to radiator
carburator air intake extension to fresh air

I figure with the A/C out of the way I'll have better access to the front of the motor to accomplish some of these tasks and a little more power being saved not turning a usless pump.

So what are the environmental concerns you speak of? I was told on another board I could just go buy some plastic plugs to cap the lines.
 

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The HMFIC
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Well....I'm not really looking for weight reduction, but considering my mph....I'll take the 30lbs gain. The real reason I want to get the A/C unit off the engine is for better engine access. My RV's temp gauge spikes up to 3/4 guage on any hill I hit whether I'm towing or not. On flat runs the needle is in the middle of the gauge, and because of her age, I'd like to do anything I can to keep the motor running cool/longer. I've had the RV for 3 years and she runs good and strong....even passed CA smog test after a tune up....and she handles well. I live 7 miles from the Beach and that's where we go most often; but we also hit the dessert with toys in tow each fall/spring and these trips is when the work out really happens. So besides the A/C removal, my list of tasks includes:

thermostat
radiator serviced
water pump
air damn from front bumper to radiator
carburator air intake extension to fresh air

I figure with the A/C out of the way I'll have better access to the front of the motor to accomplish some of these tasks and a little more power being saved not turning a usless pump.

So what are the environmental concerns you speak of? I was told on another board I could just go buy some plastic plugs to cap the lines.
ive heard of some at home mechs cracking lines and letting freon bleed off into the air. not saying you would do this but lets face it its reality. radiator thing may lead you to a new one. one that is a bigger capacity is what i would do. which would lead to a water pump also. thermo for sure that thing is a 83 and im sure needs all the help it can get. evac the lines or have a shop do it or crack and bleed into the air. take off the compresser (7) lbs then just follow all the lines and remove them as you go. you are not gonna gain much by removing everything in my opinion and even if you left it all in and never turned it on the compresser only gives resistance when the a/c is on other than that it just spins freely. i would def think about electric fans maybe two of them
 

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Instead of electric fans , you might want to consider adding a super -duty thermal fan clutch ...they move a lot more air , but do make a little more noise
 

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Some more things to check.
Timing(maybe to retarded for smog or cheap gas), carb settings (check if air door is opening on Q jet?), fan clutch, bad gas, tranny( is not overheating pulling the hill and causing the radiator to absorb it), bad thermostat( not opening all the way/old), no coolant( if you have just water it can climb) water pump, radiator (is not flowing like it used to from sitting),partial plugged muffler.
Or slow down up hills, it is a 83 after all and what do you consider hot up a hill:D Hope some things here helps.
 

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Years ago I had a moho with heating issues.
My solution was to tap into the coach water line (left the pump while traveling), ran the added line next to driver seat with an inline valve, routed new line to top of radiator, and across the radiator, punched a bunch of holes into the bottom of the line.
When temp went up, open the valve, water drips across radiator, fan and air speed pushed/pulled water thru radiator, instant 30* drop in engine temp.
Kinda McGiver-ish but hey, it worked!
Carl
 

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If it's not charged, then spinning the belt takes no hp at all. If it's low on charge then the clutch is not engaged anyhow (low pressure cutout switch).

Biggest thing to do is upgrade cooling system, get an aluminum aftermarket radiator, a OE delco STOCK thermostat (needs this to keep the ancient feedback carb working properly) and a heavy duty aftermarket electric fan set up.

If you remove/cut up all the pieces you'll regret it, there are aftermarket gasses that are 1/10th the cost of R12, have it charged every summer.

I think you will find with the upgrades I have listed you'll be able to run the air again (charged with freeze 12) cheaply, and gain some HP/cooling performance.

Then again I am not there, have no idea what the mechanical state of the engine is....

EM
 

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Carl has a great add-on idea as well, I used to use a similar system to cool my Nova when I lived in Vegas, hard to cool anything when it's 120 out :)sphss

It's nice to have something like that for older vehicles, especially if you are towing with them.

As well what the earlier guys posted, you could have tranny issues causing all your problems, best take it to someone who knows their shit.

Trust me, it's cheaper. But only if you find a good mechanic and don;t get soaked.

I can tell you sob stories all day long of new customers that just get HOSED. Ask around, find someone reputable, and yes, there is a REASON they cost 3x what pep boys charges...:p
 

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the ac condenser coil is usually mounted in front of the radiator and will restrict air flow to the rad., you can remove it if you ditch the ac,or may be able to move it forward and let more air to the radiator
 

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I have an older Motorhome as well, a 1985 Pace Arrow with a very well built custom 468 Chevy, it used to run hot...check that, very hot.

The problem was the radiator, motorhome sit too much and garbage settles out in the bottom of the radiator.

Mine is a custom made big focker...It has the same amount of cross flow as a 6 row (four extra wide rows) and holds over five gallons of coolant, I had the bottom hose installed 3" up from the bottom of the radiator to prevent sucking up sediment.

I can run it hard with the A/C blowing cold up a hill towing and it rarely goes over 200* with a 180* stat...

I would pull the radiator and check to see if it is the larges on you can fit. Also install a high performance water pump and stat, the difference is mind boggling.

As for removing the A/C, check to see if it has any refrigerant in it, if it still has gas (probably flat) have someone like a dealer pull the charge for you...

Pull everything including the condenser, but leave the evaporator, it will be more work than it's worth to pull....

Not a big fan of electric fans :D , you would need a bunch of cfm, the HP gained from running electrics versus a belt driven you will never realize IMO.

Get a good trans cooler also, run the trans fluid through the auxilliary cooler first then the radiator cooler, big gains to be had there.

Anytime I work on the motorhome I have to use Mechanix gloves, there is some sharp crap under there....

GT :)hand
 

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You can gain 10-30 HP depending on the motor removing the belt driven fan. Biggest boost he's going to get in my opinion is going to an aluminum radiator...they dissapate so much more heat than a copper one.:)sphss

You can run a 2 core in place of a 4 core and have it cool 3x as well. A high volume pump and stat is a great idea too.

Contrary to popular opinion, that little condensor does not affect airflow at all really, it's finned too:D that is unless it's plugged up with bugs/debris:)st

The older I get the more I love A/C, leave it in and charge it!

EM
 

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Discussion Starter · #14 ·
I pulled the a/c and somehow poked a hole in the radiator when I was removing the a/c condensor coil :mad:. The radiator looks to be in good shape and I can't image putting a bigger one in as I barely got this one out. The a/c condensor coil had an electric fan attached which I believe was helping ristrict natural air flow. I also do have a trans cooler that's run through the radiator, and so now the plan is to:

have radiator serviced - any shop suggestions in Oside/San Diego area?

change fan clutch

change thermostat

change water pump

I like the idea of putting a bottom loop in the radiator hose.

Thanks for the feedback.
 

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Discussion Starter · #15 · (Edited)
On the road again!

I worked on my beast last weekend and she's back on the road after installing the repaired radiator, a high performance water pump, a hp thermostat and a thermal fan clutch. She fired right up and appears to be running cooler already. I didn't take her on any big climbs yet, but I did take her for a trip to the tire shop and the temp stayed cooler than before and the temp needle hardly moved during the small climbs along the way.

I did notice a new whistling sound, which I'm hoping is just the thermal fan clutch noise mentioned in a prior post.

It's nice having the A/C unit off the front of the motor as there's much more room to get at the t-stat housing and for making belt adjustments. Also made it easier to get to some of the rusty components in and around the engine compartment so I could splash some POR 15 on them.

We're heading to the desert this weekend, so the beast will get a real test up the Cajon grade while pulling a trailer.
 

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Discussion Starter · #17 ·
well how'd she do up cajon?????
We had a good trip to the desert last weekend and my rv is definitely running cooler. Looks like my new operating temp is a little shy of 1/2 way on the factory temp gauge and for big climbs (like the Cajon Pass) the needle only nudged straight up to the 1/2 mark. What a difference! I figure 1/2 way on the gauge is about 210 degrees and I'm pleased with this result.

Of course when one thing is fixed another thing breaks. After a nice dusty day of offroading, we returned to the rv for a shower and I could hear the house water pump cycling, but water wasn't flowing to any of the spigots. No biggie as I've been wanting to put a quieter demand-pump in anyway, but a shower would have been nice at that time. I settled for a birdbath using a big pan of water. Took me a while to figure out how I was going to get at the water sitting in the tank and I finally remembered about the manual tank drains. Good times....

Thanks again for all the advice about cooling down my rig. It adds a little more peace of mind for me when I know she's running at a lower temp range.
 
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