AC removed from my RX-T .

discopotato03 · Post by **discopotato03** » Fri Oct 05, 2007 9:42 am

Hi all , spent a few hours removing all the Air Con crap from my RX Turbo . I never used it and I'm after as much airflow to the radiator as I can get . Its amazing how much more room there is to work on this car now and when the compressor goes over the shoulder there will be even more . For the time being the alternator and compressor bracket will stay as is because I reckon theres a good post fan air path where the compressor lived . BTW can anyone tell me the correct length belt for an EA82T with power steer but without the AC compressor . One will be a fair bit shorter won't it ?

Cheers and thanks , Adrian .

The Bigfella · Post by **The Bigfella** » Fri Oct 05, 2007 10:37 am

Just cut an old belt to fit and measure it

steptoe · Post by **steptoe** » Fri Oct 05, 2007 1:51 pm

Hi Adrian - yer back ! Good to see.... you looking at running one belt or two?

My GLTA has real nice air - thinking I should keep the car as it is and not fit up to my Brumby. But the momnent the A/C gives me grief it'll be gone.

Bigfella has a good idea there so you can take a sample.

discopotato03 · Post by **discopotato03** » Fri Oct 05, 2007 6:02 pm

Ended up grilling the bird at Repco , the std AC belt ATM is a 12.5 x 985mm and from the cattledog (Dayco) there is a 13 x 915 so I'll give it a try . Nothing to lose except time because Repco will exchange the belt if its a little long or short .

Actually an L series with no turbo/EFI/AC/Pwr steer must be pretty uncluttered under the lid .

"Ellie" got a bit hot in the Sydney heat the other day like to the point where I think it may have been boiling fuel in its tank . I could hear the EFI pump cavitating and this usually means this car is pressurising its fuel tank . I carefully released the pressure via the filler cap and could see fuel bubling up towards its unleaded type fuel gun flap . No more pump cavitation .
When you think about it L series steel fuel lines to the injectors are all exposed and must conduct heat to the fuel being cycled back to the tank via the regulator . I might have a think about insulating some of them if the problem shows up often enough . Just for the record the water temp didn't go sky high and its run fine since .

Before I go can anyone tell me if the elec fan sender in the off side rad tank is just a switched earth ? If so I should splice a dash switch in so that I can run that fan manually in hot weather .

Cheers A .

timmo · Post by **timmo** » Fri Oct 05, 2007 6:51 pm

yeah its an earth switch, why do you need an overide switch? the fan comes on when the engine requires cooling whats wrong with that?

steptoe · Post by **steptoe** » Sun Oct 07, 2007 12:09 pm

cooling it before its is going to need it is a good idea. This is where us humans know the engine is going to need more cooling before a basic earth switch will give us an advantage. The earth switch don't see the traffic build up outside infront of you or know that it is hot out there with heat coming off the tarmac.

I have manual earth switches on both my fans so if i am sitting in traffic i can select 1,2 or both. Esp good at the base of a mountain climb in 40 degree heat. Adrian, just watch your switches. My first attempt had a very hot switch, i think i relayed the fans on the earth switch side as well

timmo · Post by **timmo** » Sun Oct 07, 2007 6:55 pm

hmmm food for thought

timmo

discopotato03 · Post by **discopotato03** » Sun Oct 07, 2007 9:45 pm

The way I see it Ellie has a crossflow radiator and the belt driven fan may be marginal in slow traffic and hot weather . Because the tubes are long both fans get to pull ambient air through them so two bites at the cherry .
I'm not a er big fan of how most manufacturers set up thermo fans . They set them to switch on when things are a bit toasty for my liking meaning things are pretty hot in the bay and then the fan/s dump in a lot of hot air .

The way a properly designed cooling systems works is that the radiator tanks have a reserve of cooler than water jacket temp water and the thermostat is used to regulate the temperature . Idiot design nowdays has it so that the thermatic fans don't switch on until every drop of water in the whole cooling system is fairly hot . In other words they are trying to control water temp at low speed with the fan switches and doing it that way leaves no cooling system reserve - and really hot under bonnet conditions .
I'd actually prefer a lower temp switch but finding one that fitted would very likely be difficult and expensive . Don't forget that the radiator temp can be quite low and it won't matter because its the thermostat thats regulating water jacket (heads/block) temperature .
At 21 yrs and 261000 k's old I'd rather err on the slightly lower coolant side which is why Ellie also has a slightly lower than std temp thermostat . Once the coolant rises above that which the thermostate regulates at it means that the radiators running out of cooling reserve and opening to allow full flow . Its then up to the fans to pull as much air as possible through the fully flowing radiator to waste the heat . As far as I'm concerned if the fans aren't capable of pulling the temperature back down to below that which the thermostat regulates at I have a problem . So I need both fans working when I want not when Subaru thinks its Ok .
Also if I can made the cooling system adequate for the cost of a relay and switch its cheaper than one off custom radiators and my rad looks to be in good nick .

Before I go don't make the mistake I did in thinking you can remove the AC compressor and leave its bracket behind to mount the alternator . The compressor body forms part of the main alternator mount so you really need a set of non AC L alternator mounts - which I have but not short belts .
The front two lower compressor bolts are a real pain to get at and I could only reach the left hand one by removing the power steering pump pulley . Needless to say stupid had to fit the compressor back in though without that front left bolt . In act two I'll have access to a range of belt lengths so I can trial fit to size .
Lastly it didn't escape my attention how difficult that rubber elbow into the top of the water pump may be to get at with the compressor in place . Can't wait to lose that bloody thing ...

Cheers A .

steptoe · Post by **steptoe** » Mon Oct 08, 2007 10:33 pm

and go the double the price larger bore tridon thermostat with a 34mm hole instead of 29 TT-2041 180 [only temp in catlog] if you ain't already done so

timmo · Post by **timmo** » Tue Oct 09, 2007 8:23 am

how much and what temperature is this?

steptoe · Post by **steptoe** » Wed Oct 10, 2007 12:35 am

'bout under thirty bucks. 180 degrees F take off thirty=150 and halve it - about 77 deg C the temp recommended for efi to work within specs but allow more water to flow

discopotato03 · Post by **discopotato03** » Wed Oct 10, 2007 9:57 am

I think you'll find the conversion works out to .

180F = 82.22C
170F = 76.66C

So mine regulates at ~ 77C - provided the radiator water temp is 77 or lower . My aim is to keep the rad temp down so that the thermostat remains the controlling device .

Cheers A .

timmo · Post by **timmo** » Wed Oct 10, 2007 5:00 pm

discopotato03 wrote:I think you'll find the conversion works out to .

180F = 82.22C
170F = 76.66C

So mine regulates at ~ 77C - provided the radiator water temp is 77 or lower . My aim is to keep the rad temp down so that the thermostat remains the controlling device .

Cheers A .

so is yours the one that jono is talking about? i'd prefer 82 to 77C. So the part no. listed here is for 180F meaning 82C?

timmo

discopotato03 · Post by **discopotato03** » Wed Oct 10, 2007 10:23 pm

Not sure , mine runs the 170/77 deg and fuel consumption is surprisingly good . Last tank I got 640 k's and this time it'll romp in 600 + . Not too sad for a 21 yr old car that shows ~ 85 - 110 pounds compression pressure . I don't think the 5 deg C lower water temp makes any difference to how the archaic mid 80's engine control system runs things .

steptoe · Post by **steptoe** » Thu Oct 11, 2007 9:43 am

I think the 180 is the only one avail coz it is the suggested temp to run all sensors happy. I am a colder thermstat user by choice generally but thort i should try the correct one on my first efi. I agree, 5 degrees would hardly be noticd by the ancient electrics of these beasts, and they generate enough heat so the ability to keep it stable at all times gotta be safer than worrying about max fuel efficiency.

Matatak · Post by **Matatak** » Thu Oct 11, 2007 9:23 pm

from what i know. the temp on the thermostat is only when it starts to open and not when it will be fully open (that may be another 10 15 degrees)
and im with Steptoe (Jono) i wuls use a colder thermostat if i knew of one for my EJ but havent found one yet.

discopotato03 · Post by **discopotato03** » Thu Oct 11, 2007 10:53 pm

Update . A/C compressor permanently removed and the alternator refitted using 92 L carby non A/C mounts . The single belt runs around the inner of the dual pulleys and lines up with the alternators single one . The belt is the Dayco one for non A/C but with pwr steer cars ie 13A0980 . Its a little tight to fit possibly because the spacer under the sloted bracket may be a tad thick but workable . The belt will be replaced with a longer one tomorrow so that the alternator can be hinged up higher and out of the clutch fans hot air path .

I noticed that the top of the radiator in an L series sits further back from the support pannel than there's room for which is surprising considering the lack of space between both fan shrouds and the cam belt covers . Also I think the MY type OS or inlet rad tank is wider than L series and may be able to be soldered onto the Impreza core thats dimensionally thicker than the L core . They have the water inlet and elec fan switch fittings I think in the same place . I'd like the fan switch as high as it can be in that tank .

Lastly the manual shows where the fan control relay is mounted so the means to arm it with a manual switch just got easier .