'73 Resto & Suby 6 Conversion, or a primer on "How to convert your 914 to a Subaru 3.0" Options

[Andyrew]

Looks great!!

What size hoses did you go with?

[Chris H.]

Looks great!!

What size hoses did you go with?

Guess I better order the 1.25 eh Kent (IMG:style_emoticons/default/biggrin.gif) ? You ready for it? If you want to try the existing setup first that's totally cool.

Your radiator support it AWESOME man. Nice work. I have literally the exact same radiator setup. You'll love it.

[76-914]

Looks great!!

What size hoses did you go with?

Thx Andy. The hose size is still up in the air. I need to get this set up running, compare notes then I'll decide. It may not be necessary. Bob (BigKat83) is running the same size hoses albeit a different route and a larger radiator than my old radiator, w/o a hitch. However, I'm not sure if he spools it up and keeps it there. That is when I experience the temp rising. So, if what I believe to be a cavitation problem persists and/or the temps won't stay in range without "fan action" when rolling then I'll run 1 1/4" beneath the car.

EDIT: Just read your post Chris. I'll know in the next week to 10 days. Have 2 birthdays this week so I may not be ready this weekend. (IMG:style_emoticons/default/sad.gif) Did you get to work on Blue this weekend? (IMG:style_emoticons/default/beerchug.gif)

[Chris H.]

Yeah no rush at all. Just wanted to make sure I wasn't holding you up. I say try it how it is. Probably be fine.

I'll be working on mine this weekend for sure. Hope to get that engine out.

[76-914]

I was able to squeeze in a quick run this evening after reconnecting the hoses and topping off the coolant. The new radiator added about 1 qt to the cooling system capacity. I let it idle about 10 min. and the Subie factory gage was approaching the mid point i.e. operating temp, when I pulled out of the garage. I drove around the hood for 10 min's (<40mpn & 55F) and the needle never moved nor did the fans kick on. Ran it up to 55mph and the fans kick on. Drop to 40 and they go off, and so on.
This is the 1st noticeable improvement. I will pull the fan's fuse before the next run to see what happens to the temps at 55mph+. Either the sensor cut in / cut out is not compatible with this system, in which case I'll go to an after market sensor, or it's time to order some 1 1/4". When the OLD radiator was installed it took several minutes for the fans to shut down after they came on. As stated above, they only came on above 55mph tonite. They also would kick in on the hi way quite often with the old radiator in place. I may find that this isn't an "and/or" scenario but an and/and scenario. More later. (IMG:style_emoticons/default/beerchug.gif)

[914forme]

Sounds like great progress.

I am going 1-3/4" on cold side 1-1/2" on hot side. There is enough room on the EG to go full 2", but 1-3/4" seems like it should function just fine.

Can't wait to see your results. (IMG:style_emoticons/default/popcorn[1].gif) Might make me change my mind.

[76-914]

Just noticed your question Andrew. 7/8 & 3/4".

Today I drove with the fans fuses pulled. I drove around the "hood" for 10-15 mins w/normal stop n go. OAT was 75F and speeds were < 45mph. Engine temp stayed centered. I then hit the Wine Country back roads for another 30 mins. OAT 75F, speeds < 62mph, engine temps still centered. AHAAH I thought those fans were running too much and now I know they were.
All this thought about changing my cooling system began when I installed a light to tell me when the fans were running. I noticed they came on (and off) when on the hi way. The temps were always centered but damn it, those fans shouldn't have been on. I also noticed that if I stopped then started the engine the fans did not come back on, although they had been running 10 seconds before???
So the cut in/cut out factory set points do not appear to be the best set up for my system. Looks like an adjustable fan controller is in my future. I should be able to dial it in quickly as I know what the temp gage should read.

Next test hop I plan to run some realistic hi way speeds 70-80mph with a bit of higher RPM driving to test for 2 things. Both were mentioned in an article that George posted in Chris' thread. One is cavitation the other is high pump head pressure. More later.

[Chris H.]

I ditched my ECU fan controls. Never ran right for some reason. Installed the Derale 16759. It has an AC override circuit. Very easy to wire up to a switch if you want to run it continuously too. It's about 99% less complicated and only requires one relay which is included. The initial factory setting is WAY low on the Derale BTW. Kicked on at like 170 or something. Easy to adjust though.

[914forme]

You can also look at the PWM Fan controller.

It is a bit more, 65 Amp capacity, and A/C override. Big difference is it controls fan speed so the fans are only turning at a high speed when the need to be. This reduces noise and amperage loads.

Derail makes some nice stuff.

[76-914]

I ditched my ECU fan controls. Never ran right for some reason. Installed the Derale 16759. It has an AC override circuit. Very easy to wire up to a switch if you want to run it continuously too. It's about 99% less complicated and only requires one relay which is included. The initial factory setting is WAY low on the Derale BTW. Kicked on at like 170 or something. Easy to adjust though.

I was reading the negative reviews on this model and decided that I should go w/ an upper line model. Then I noticed the same complaints re: models that are 2-3 times as much. That's when it occurred to me that the problems with any of these units is most likely theINSTALLER. More especially, those that were received DOA. One guy said he had 2 dead ones in a row. Riiiiiiiiight. Notice he ordered another brand after that. One with pictures instead of words. (IMG:style_emoticons/default/lol-2.gif) Think I'll try one of these! Did you get that engine out last weekend? (IMG:style_emoticons/default/beerchug.gif)

You can also look at the PWM Fan controller.

It is a bit more, 65 Amp capacity, and A/C override. Big difference is it controls fan speed so the fans are only turning at a high speed when the need to be. This reduces noise and amperage loads.

Derail makes some nice stuff.

Yea Stephen, I would go with this but it is overkill for me. I did like the manual override feature, though. If your running dual fans and want an adjustable model the field quickly drops from over 50 units to just a couple of units. The variable speed feature is neat but I'm hoping my fans won't be required so much that I need a feature like that. The fans that came with this unit are only 80 watt ea. (80/12=6.66amps ea.).

[Andyrew]

Im going to be running the Davies Craig water pump and LCD control panel, it circulates both the water pump and fans perfectlg for speed and timing to maintain the desired temperature.

I got both for ~320 shipped from australia. Theres a link to the ebay auction/seller in my thread, ill get it in a bit.

[rnellums]

Im going to be running the Davies Craig water pump and LCD control panel, it circulates both the water pump and fans perfectlg for speed and timing to maintain the desired temperature.

I got both for ~320 shipped from australia. Theres a link to the ebay auction/seller in my thread, ill get it in a bit.

This is very interesting!

[Chris H.]

I was reading the negative reviews on this model and decided that I should go w/ an upper line model. Then I noticed the same complaints re: models that are 2-3 times as much. That's when it occurred to me that the problems with any of these units is most likely theINSTALLER. More especially, those that were received DOA. One guy said he had 2 dead ones in a row. Riiiiiiiiight. Notice he ordered another brand after that. One with pictures instead of words. (IMG:style_emoticons/default/lol-2.gif) Think I'll try one of these! Did you get that engine out last weekend? (IMG:style_emoticons/default/beerchug.gif)

Yeah it's VERY easy to install. Given what you've accomplished with your harness this is a snoozer. Everything is very well labeled. I think I posted the instructions in my build thread. Guessing the guy who had 2 dead ones crossed the positive and negative wires ... which DOES release the magic smoke. Even I know that. Bob recommended this one BTW (shocker).

I have the engine ready to drop. Just gave it a few days for this green stuff to drip off (antifreeze). I have a couple of small dogs, so a few drops would be deadly for them. Will drop it later today and post some pics!

[76-914]

For the few that are following this Boredom Bowl, I will continue to post these uninspiring updates on my cooling system. I'll try to keep these brief until it's complete.
Hit the hi way yesterday for about 40 min's. This hi way has about 6 stop lights along the route and I kept it at 70mph+. Why this test? In reading one of the articles that Stephen posted it spoke of a head pressure build up on the pump. I had noticed this phenomenon early on but wasn't sure what was behind it. Heat or pressure? I used this MC filler neck in the front trunk and noticed a discharge after some hard runs so I poked a hole in the top of this water bottle to catch the overflow.







It was only then that I noticed how much it discharged. No problem. I'd just pour it back in the expansion/recovery tank in the engine bay every once in a while. So now that I know why this happens I want to see if there is has been a change since the radiator swap. I didn't see any discharge w/ this radiator but I didn't "horse it" either. I'm betting 4000rpm+ and I will see it return unless this radiator flows more freely. 70mph is only 2800rpm.
So all this (IMG:style_emoticons/default/stromberg.gif) and what did I learn? Just that the discharge is not constant. I may have the chance to "horse it" this afternoon to see if high rpm is related to that discharge. Seems logical that pressure would increase with rpm. If that's the case, and I suspect it is, I will change hose size. More later. (IMG:style_emoticons/default/beerchug.gif)

[914forme]

Im going to be running the Davies Craig water pump and LCD control panel, it circulates both the water pump and fans perfectlg for speed and timing to maintain the desired temperature.

I got both for ~320 shipped from australia. Theres a link to the ebay auction/seller in my thread, ill get it in a bit.

(IMG:style_emoticons/default/headbang.gif)

Nice, and it eliminates a lot of the items we are talking about in this cooling water pump cavitation.

Thermostat is gone, water pump is gone, and line sizes might be back down to a more reasonable size. Stock it uses 1-3/8" hose, accepts hoses from 1"-2"

I am thinking I am sold on this idea, Thank you Andrew for the tip.

Now to grind the impellers off a water pump.

[76-914]

We may all end up going this route but I had a pleasant surprise after yesterdays drive. I horsed it around on some back road twisties yesterday and did not have any discharge into the water bottle reservoir. Maybe a little in my pants as a Mountain Lion crossed the road in front of me but none in the water bottle. (IMG:style_emoticons/default/blink.gif) Previously high RPM's preceded (not ready to say caused) this discharge. Absolutely no reason for this unless the newer radiator has < flow restriction than the old one. Maybe the 3/4" return IS ample. Regardless, it's time to throw the condenser back into the mix and see what happens next. (IMG:style_emoticons/default/beerchug.gif)

[76-914]

No apparent changes to the indicated temp since throwing the condenser back on so I installed the Derale fan controller. The factory ECU was not shutting the fans down once they activated so I'm hoping this unit will produce favorable results.
It's quiet compact:



Compared to my old Rat's Nest.



Just needed to make this Tee for the sender and I was good to go. Look out Rt 66!

[914forme]

Looking good, got to love progress!!!! I think you will be happy with that controller they work very well.

[Chris H.]

Nice work Kent. So simple. The stock system thinks too much doesn't it (IMG:style_emoticons/default/biggrin.gif) ? Dang computers (IMG:style_emoticons/default/screwy.gif) . I like how you can easily wire it to run all the time if you want with a switch. Nice for the first few days of the conversion too. Next time !

[76-914]

Thx guys and just as you you predicted Chris, the factory setting was way too low.