Vdub Rad w/ AC

[lookforjoe]

I followed racerX's excellent guide to do my rad install, but made some changes, in part due to routing around the ac condensor & lines.

Ended spending at least 5 hours on this - longest rad install I ever did!

Hose routing I chose to use..

stock routing: upper hose still goes to right side. Hose is a composite of stock rightside hose (lower portion) and stock leftside hose (Gates 25808, upper portion) connected with 1.5" coupler

lower hose is Gates 21263, as used by RacerX - I had to cut off some of the wide end, it was too large for the fixed pipe neck.

Fan is Mr Gasket 14". A little large, but I already had it on hand, and I just had to space out the upper ties using the stock lower radiator mount bushings, to allow clearance for the recessed bracket on the body (cut & folded as per RacerX's directions) I used a old Volvo radiator sensor "T", as the coupler here & wired the sensor, so I can use it if needed.

Rad installed - left bracket

right bracket

AC Condensor lower brackets - made from Volvo central lock motor bracket

Upper AC condensor mounts - cut another Volvo bracket

right

left

fitment around AC lines (pic was partially lightened in photoshop to show detail - hence the funky look)

taken during test fitment -I didn't forget the clamps in these two pics :rolleyes2:

lower hose

left side fitment - no contact/chafing

I ran the engine & bled the rad, seemed to be all good, so we went out to dinner in it. Started to overheat after getting off (drove about 15 miles) the highway. Coolant pooling in the forward storage cavity front edge - I thought maybe the top was pressing down on the bleeder & allowing the coolant to escape, but when I added water at a gas station (reservoir was bone dry!), it certainly appeared to be leaking somewhere up top front as I filled it. Got the car home, didn't overheat until the last mile. I ran it in the driveway, adding water until the engine temp was back to normal, shut it down. Hopefully no damage was down to the motor.

I'm assuming my bleeder valve is leaking - I used teflon tape to seal it. I'll have to check it out in the morning & see. Probably just pull the rad & reseal the bleeder & blanking plug with silicone instead. I don't have a pressure tester, so I'll hopefully be able to determine where it's leaking from residue of today's run.

 

[Black-Tooth]

Welp... I dunno... but one BIG thing concerns me...

First though...

Why not BORROW a pressure tester so you can stop GUESSING at what is/was wrong. Andrew (WRXDREW, I believe...) told me he went to one shop that allowed him to RENT a tester or BUY it if he wanted to keep it... Others have "borrowed" ones from Pep Boys and Auto Zone.

You also don't mention if you were overheating PRIOR to replacing the radiator. I imagine you were if this is why you are replacing it... But I wonder now if you PROVED the radiator was the problem.

Hopefully if you have gone to this much trouble you are replacing the T-Stat also.

Lastly... ONE fan on an A/C equipped car? Are you planning to run this fan at all times when the A/C is running? Usually, one would have two fans and one would be exclusive to the A/C, as I'm sure you are aware.

 

[bbrown]

Good write-up

The pictures were excellent as well. Thanks for outlining your install.

I'm going to agree with Tony with regard to the fans. Especially with AC. Maybe you already have 2
but didn't mention this? Donno, but you definitely want 2 fans in there.

If your wire harness does NOT accommodate 2 fans, DO NOT parallel the one fan line to 2 connections.
Run a separate line back from the relay in your fuse panel. The wire and
connections can't take the current otherwise.
Not long term anyway. (I have seen many burnt connectors running to the fan motors)
If you need the connectors, do a search on eBay for "Yuasa heated battery tender".
It's rated for a LOT more current than the normal battery tender connection and the only one
available I know of that will do the job.
Or if your lucky, Matt Brannon can cut a set off of 2 bad fan motors for ya. Those are the heaviest gauge
I've ever seen in that style connection.

Good luck with your cooling project and let us know how it goes.

 

[lookforjoe]

Yes, Tony - I replaced this due to excessive temps when idling. I had already replaced the t/stat & gauge temp sensor last fall.

The issue was entirely due to the bleed valve installation height. The targa top latch was intermittently pressing on the valve when stowed, hence the loss of coolant. :rolleyes2:

I pressure tested the system this morning, and it held 17psi without any issue.

I lowered the left side of the rad support bracket by inserting a 1/'4" alignment shim - a "U" shaped washer, basically. That dropped the valve to this..

..which was STILL too high - as soon as I stowed the top & drove around the block, the jolting caused the latch to contact the bleeder.

So, I epoxied a shouldered hat to protect it. Basically a more rigid version of this test sample...

Normal temp now...

pressure..

after idling 15mins..

...at which temp the fan kicks in.


My car is wired for two fans, but this single fan pulls way more cfm's than the two fiat fans combined. My AC isn't working now, so I'm wondering if it doesn't complete the circuit unless the AC fan circuit is complete. I'll try plugging the fan into the AC harness instead of the stock harness later. I cut the connectors off my (good) Fiat motors I also have a Volvo temp sensor in the lower hose, which I may try instead of the stock Fiat one, to see if it engages the fan at a lower temp. I did also wire a bypass circuit for the fan last fall, so I can manually activate the fan (via the stock sensor circuit)

 

[Black-Tooth]

Hmmmm...

So that bleeder is some sort of pushbutton affair... interesting...

Well, ya should have all the air purged out and the system holds good pressure... all good.

What's NOT good it the high temps. Your dash guage is indicating 240 degrees and with 13 pounds pressure, the boiling point of the coolant would be around 251 degrees.

Loose just ONE pound of pressure (like with the top hitting the bleeder) and your coolant flashes to STEAM and doesn't circulate or absorb heat too well.

As I was saying to Greg in CT... mine operates beween 185 and 210 in 85 degree air sitting still and the fans (I have two now) cycle. My fans NEVER come on if the car is moving... and generally do not operate at all for 9 months out of the year!

Try leaving the engine cover WIDE open and see if it changes anything drastically.

HTH... let us know if ya find anything...

OH... and one other thing... maybe... since your A/C is inop... pull the condenser and see if that has any major effect. That is the ONE variable I cannot test for and it is the ONE common thing that you, Bob, and Greg do have in common.

 

[racerx]

bleed valve being pressed by targa top latches

sorry I forgot to mention that may happen depending how you stow your top in the frunk it happened to me too. To resolve the problem I just turned the top around so the latches are on the right side off the frunk compartment.

 

[lookforjoe]

With the new rad - the AC condensor is FAR from contacting - unlike the factory setup where the condensor sits DIRECTLY on top of it.

The AC did work before I messed with the rad, so I may have damaged the lines into the condensor, they didn't look great to begin with.

Driving, the temp gauge shows just under 190º, and rises to 190º idling. Extended idling brings it up as indicated. My fan doesn't even kick in 220º, so maybe I'll try the Volvo fan switch. What temp is the Fiat sender supposed to kick in?

I haven't check the actual temp with a test gauge to confirm whether the gauge is accurate. It certainly didn't register even close until I replaced the sender last fall.

I'm wondering if I should just do a water pump - it does have 117K, after all. That, or BB's electric IC helper pump mod.

 

[lookforjoe]

sorry I forgot to mention that may happen depending how you stow your top in the frunk it happened to me too. To resolve the problem I just turned the top around so the latches are on the right side off the frunk compartment.

Would have been nice if you'd mentioned to look out for that :rolleyes2:

I'm just glad I didn't damage it! Thanks again for your excellent write up, it was a very useful reference!

 

[Greg (in Conn)]

My Corsa usually runs about 190*

which is fine...The new sendors I got from Midwest last year cycle at 190* so I always maintain never getting over 200* but my dual fans are constantly cycling on/off.

That raintray does hold in a lot of heat...hmmm

 

[lookforjoe]

which is fine...The new sendors I got from Midwest last year cycle at 190* so I always maintain never getting over 200* but my dual fans are constantly cycling on/off.

That raintray does hold in a lot of heat...hmmm

I'm running without the raintray since last fall, and I can't say it made any noticable difference at all.

I'll try running with the cover removed entirely, just for laughs. :sigh:

If the Volvo sensor doesn't kick the fan on earlier, I think I'll invest in a lower temp sensor from Midwest, also.

 

[Black-Tooth]

Well... I'm running out of suggestions...

..

With the new rad - the AC condensor is FAR from contacting - unlike the factory setup where the condensor sits DIRECTLY on top of it.

Is the spoiler on correctly? Is the new radiator at the correct angle as was the stock radiator? Not leaned too far back or foward?

The AC did work before I messed with the rad, so I may have damaged the lines into the condensor, they didn't look great to begin with.

If you no longer have a charge or care... pull the condenser out altogther... just for laughs... (Like I said, I'm running out of ideas and this is a difference.)

Driving, the temp gauge shows just under 190º, and rises to 190º idling. Extended idling brings it up as indicated. My fan doesn't even kick in 220º, so maybe I'll try the Volvo fan switch. What temp is the Fiat sender supposed to kick in?

From what I can tell, on about 210 and off at about 185. When the fan operates... are you saying it does not drop the temp... it just keeps climbing? If so, check rotation... pulls from front to rear!

I haven't check the actual temp with a test gauge to confirm whether the gauge is accurate. It certainly didn't register even close until I replaced the sender last fall.

Well, it acts fairly accurate. Use one of Mom's baking thermometers in the reservoir. I used two and they proved my guage was right on.

I'm wondering if I should just do a water pump - it does have 117K, after all. That, or BB's electric IC helper pump mod.

Well... a W/P usually works or it doesn't... leaks or it doesn't leak. In rare cases VANES have corroded or been eaten away. I've seen this ONCE in 62 years.


Before you do Bob's thing... try turning up the idle 200 rpm and see if that makes a difference.


More ideas, possibly... after you reply.

 

[lookforjoe]

Thanks for the reply....

..

Well... a W/P usually works or it doesn't... leaks or it doesn't leak. In rare cases VANES have corroded or been eaten away. I've seen this ONCE in 62 years.
Before you do Bob's thing... try turning up the idle 200 rpm and see if that makes a difference.

Not being familiar with the Fiat W/P vane design, I assume that there could be an issue with insufficient flow * low rpm, since the temp is fine now (180º) when moving, even if slowly.

I'll try raising the idle a tad.

Spoiler is on correctly. Rad angle deviates only slightly from stock, due to increased height.

Not removing the AC, I like it. Converted to R134a yesterday: the problem is that since the condensor is no longer directly attached to the rad (several inches gap), the draw through effect from the rad fan is insufficient to cool the condensor :hmm2: - I now need a secondary pancake fan to mount to the condensor :rolleyes2:

Temp drops when fan engages, the larger fan works wonderfully for that, it would just be better if it engaged sooner. I hooked up the Volvo sender last night, so I'll idle the car for a while & see when it kicks in - although the ambient temps have dropped the last few days.

 

[lookforjoe]

You are using distilled water right?

No, I've never used distilled water in any of my cars. One of my Volvos went to 450K, same cast iron block/aluminum head setup - never had an issue. Current Volvos I've owned are all aluminum motors, never found the need to use distilled water in them either. I use standard ethylene glycol based coolant.

Current situation is that engine temp stays below 190º (180-185º) when moving, even when I ran an sustained 80-100mph * 3/4 throttle today. Once parked, temp rises to 220 after about ten minutes, even with idle raised over 1000rpm, and engine cover wide open.

I'm going to replace the water pump when I pull the head to install one of Matt's modified cam/cam box setups. If it still tends to run hot * idle after all that, I'll do the BICBM :grin:

 

[lookforjoe]

Thanks for the suggestion, anyway.

I can't see this making a difference to the coolant flow at idle, though. I flushed the system last fall when I did the T/stat, and it's clear now.

 

[Black-Tooth]

Well... its 'cause I always used Perrier in my cooling system...

... and so do most SoCal-ers...

(Always Designer Label Conscious!)

 

[budgetzagato]

Optimistic Bias...

It's a common perception, it's why we do so many things we know are statistically unsafe or ill-advised, from driving with only one hand on the wheel, to marriage.

It's true that if you have very hard water you'd be best to use distilled water, but others on our forum swear by using their tap water because it contains some minerals, so that the tendency of the water is not to try to dissolve the metals of the engine.

It's worth pointing out that if a particular X has overheating issues, distilled water or not won't make a difference, there is likely a mechanical problem with the cooling system.

 

[halojm]

You might want to check that water pump

Mine had less than 30k miles on it and worked reasonably well, but here's what it looked like when I pulled it out (probably from years of tap water...)

Here's what it looked like after I wire brushed off all those years of TAP WATER corrosion (I still replaced it)

 

[lookforjoe]

I get your point, Chris.



The thing is, unless distilled water somehow improves the coolant's ability to dissipate heat when flow is low, then it's not going to make a difference.

I do not have scaling/sludge/buildup in my system. All the tubes were clear, the radiator was clear, my t/stat housing was clear last fall when I did the t/stat

After I do my head/cam/water pump, I'll put the same coolant/water mix I'm using now. IF I still have a flow/temp issue after that, I'll consider switching. :grin:

 

[lookforjoe]

My FFDynamics 7" 500cfm fan arrived on Saturday.

Got time to install it today. It's stock orientation is pull type, so I reversed polarity to use as push type, as I found there is enough clearance to fit between condensor & grille. And it's RED

wired into stock AC fan circuit

Found that the idle compensation valve was stuck- base idle with AC on was so low it was not charging properly. Removed & turned the solenoid on it's base about 1/2 turn, was enough to free the plunger.

 

[eflexter]

????

I may be missing the point here. I'm dense sometimes so my wife says...... But at idle, cars ALWAYS overheat because there's no air going though the rad. If the car heats up only at idle, then replacing the fan switch would be my first thought.

I wouldn't trust the stock guage for a true reading. If you are really overheating you'll have bad spark knock and burnt white spark plugs. The idea of the kitchen thermometer in the catch tank is right on.

If the car is really hot all the time, try a cooler thermostat. Just be vigilant about fixing the easy stuff first. It catches most of the problems that way. I've had lots of bad brand new parts so don't rule out a new part being broken.

I think a bad water pump would be the last thing to try. And if it's rusty like the picture above, pop out the freeze plugs and scrape out all the crap accumulating in the water jacket!!!