Soob swap

[edward ericson]

Spent today re-routing wires, soldering ring and spade ends, shrinking heat-shrink tubing, looking for more wire. I think I have the fan all squared up now. But not so sure.

After all the wires were done (and by “all the wires” I mean “all the wires I can get to without crawling under the dash.” There are many, several, myriad other wires yet to wire) I set about tightening stuff on the hoses and pipes and stuff. Had a little weep on the connectors for my temp gauge bulb thing. Had a little one under the driver’s side where the two pipes meet. I disconnected those to empty the high side pipes of the pure water I tried to run through it the other day. Then I filled it back up with Prestone, 100 percent. Then I put a little more prestone in the overflow bottle and put the cap on the radiator. Then I loosened the clamp holding the high side pipe to the top of the engine to make sure it was all wet there. It was.

Started her up. She starts up and idles nice. I got tach working now so i can see what RPM she idles it. It’s 1200 or so right now.

Then I waited for the temp gauge to start creeping up like it ought to do.

She ran maybe 10 minutes and the needle has still not moved off 90.

As in 90 F.

ThenBANG!

The low-side rad hose blew off the engine where it connects to the inlet where the thermostat is.

So I shut off the engine.

There was a little steam as it spread across the driveway, but really not much. I could hold the hose end right away.

Right now I think I just didn’t tighten it enough. The fitting for the stainless steel flexi hose it a bit of a fiddle. It comes with silicon donuts to allow it to fit several size water outlets. The one I had on this fitting was a little wracked.

So I’ll put it on more carefully tomorrow and try again. 

edsnova2014-07-02 07:16:23

[edward ericson]

Think I might have trouble.

I reattached my back end, low side hose and went through and tightened the other connections. 

Refilled the coolant and ran the engine yesterday until the driver’s side coolant pipe got so hot I got worried.

All the time I had a bit of a cloud coming out from under the engine. Not much, but you could see it about 20 seconds after startup and it faded, but was still noticeable a minute later. Until then I had taken this to be exhaust paint still burning off/curing. But now re-thinking. Could it be the dreaded head gasket failure?

Doesn’t smell like much, but there isn’t much antifreeze in the block per se. I could not make it condense on a glass. So there’s still hope it’s just Krylon smoke.

At the end of this little exercise the temp gauge had not budged. The car had been running 10-15 minutes and the left side felt hot. No coolant was going through to the other side in the big hose. The overflow tank was filling up.

I shut her down and went away.

Came home and the overflow had been sucked dry, and there’s now space in the top of the radiator.

Pretty sure this is not going to be nothing.

edsnova2014-07-02 07:18:11

[HappyJack]

Hey Ed,

I do believe that when you were born, you were accidentally given an extra shot of TENACITY — 3 times over……and of course the extra patience and naturally the double helping of dexterity to boot……

Really great stuff you are doing with the BCW.  Once you are running down the boulevard with the Snoopy hat on, the goggles, the windshield folded and with that smile pasted on your face it will all seem worthwhile….!!!!

Looking forward to seeing Bridget and getting the “rest of the story” on the build build from you when we get to Va Beach this year.  After all, Emma is a fine example of a BCW and is in need of something more reliable than the “stump-puller” 200 ho engine she now calls hers…..

Hmm……

You wouldn’t by chance be contemplating going into the business of retrofitting other people’s  BCW’s  on the side for fun and profit would you?

GREAT WORK…..and here I am complaining about  having to change the sand seal on my pulley on Emma…..!!!!

[Rich Kallenberger]

Is it possible that there is something fundamentally wrong with the coolant flow path. Pardon me but that is a technical way of saying “is something plugged up, blocked off, or put on backwards?” Yours is obviously not a simple conversion and many things could trip you up.
Best of Luck and Success

[Peter C. King]

Ed,

 

Do you have a loop of hose that is higher than the radiator cap?

 

Do you have a vertical loop of hose anywhere in the system?

 

Either will trap air when the system is emptied.

 

It sounds as if you have an air bubble that is stopping coolant flow. Once you have that out of the system it should work normally.

 

That the overflow tank is empty would suggest that there was room in the system for more fluid. It’s outside the system.

 

That there was room in the radiator says that there is still a bubble in the system. It is inside the system. 

 

You may need a few heat, cool, refill cycles until the system stops venting the bubble through the radiator cap and sucking fluid in from the overflow tank.  

 

BDriver

 

[billnparts]

Pete is correct…the design of the Subaru flat 4 is a PITA to get air out of the cooling system. Your conversion with the elongated cooling pipes to the front would compound the problem. There are tools to suck the air from the system at the rad neck. Check for or install a bleeder at the highest point or continue cycling the system to bleed off trapped air.
Patience, Grasshopper.

Bill Ascheman
Fiberfab Ford
Modified 5.0, 5sp., 4:11
Autocross & Hillclimb
"Drive Happy"

[edward ericson]

Thanks, guys.

Kall: could be. I did check the thermostat to make sure it opened at the right temp. And it’s an original type which means it’s too big to install upside-down like some of the aftermarket replacements can be. I know because I checked. The heater core is supposed to be flow through and I did remember to take the plugs out of it before putting the pipes on it. . . .

BDriver: No. The rad cap is the high point but it’s not a smooth flow from engine to rad cap. There was definitely air in her last time. And it’s def. a PITA.

But yes: there is a near-vertical loop where the heater core feeds. That is also where I’m trying to take my temperature. Sounds like it might be a good idea to fill up the heater core and throw some coolant down those hoses before the next startup.

I hope like hell i did not blow a head gasket already but if i did, well, we all thought this might happen and Bill did sort of tell me so already.

In my defense–if you can call it that–it is my belief that the head gasket was sound when I bought the thing so if it’s broke now it’s because I broke it, so that means if I’d put in new ones I might have broke them too and be doing the job twice instead of once.

See? Lazy bums also use logic.

Thanks again for the encouragement. I’ll try again this weekend. Fingers crossed.

[Peter C. King]

Ed,

 

Heater cores are notorious for trapping air.

 

Your temp probe may be in the air pocket. 

 

Filling the heater core and hoses is a good idea.

 

BDriver

 

[Anonymous]

Ed when you fire it up to check it the next time turn on your heater full blast. It will help purge air from system. Like sifoning gas air needs to be removed. Could start at water pump and check for coolant along path of complete system.It can be done. Also might borrow a tester to see if exhaust is getting into coolant[head gasket].

[edward ericson]

Thanks, George.

The heater is not installed yet. The wires are not hooked up and it’s not bolted in. And I have not cut the fiberglass inside the passenger compartment where I’ll need to in order to tuck the heater in right. Haven’t made the bracket for it either.

OK, so. The heater should be–is, I think–but will check–a flow-through model. There is no valve to shut off coolant from it when you don’t want heat.

And that is a good thing, because the Subaru cooling system is designed so that the hot water goes to the heater core first and then back to the block right above the thermostat. The hot stuff that goes to the heater core is supposed to tell the thermostat to start letting cooler water into the engine. 

That’s why, if you have a shut off valve in your heater core like a lot of cars have, your Subaru will overheat. The thermostat never sees hot enough stuff to open it.

I will prime it tonight or tomorrow.

Or maybe I’ll just loop it out of the system and see if I can get the thing to flow without the core.

Really hope I did not blow the HG. 

Also, from what i have read, the head gasket on these cars tends to let coolant come out through the gap between the head and the block. Not so much through the exhaust, as is common on other cars. Hence my concern.

[billnparts]

Yes Ed, most Subarus will leave a puddle when they let loose.

Bill Ascheman
Fiberfab Ford
Modified 5.0, 5sp., 4:11
Autocross & Hillclimb
"Drive Happy"

[edward ericson]

Well I got back after it today & have not yet found joy.

I took out the heater core and tested it for flow. It flows. 

I took it out of the system anyway.

I filled the small heater lines (and also tested flow thereby). They were and are full. 

I topped up the block and the radiator.

I started the car and let ‘er run.

First time I got no temp reading at all. The hoses all held but pretty soon the overflow tank was pissing as the high side pipe gurgled forth again. Even then the fluid was not hot. I let her run for another 10-15 minutes before I lost my nerve. 

With the engine shut down she eventually sucked the overflow near to dry.

So I re-did all the steps above. Sure enough there was no fluid at the temp bulb again, so I more carefully refilled that. Refilled the rad.

Started her up.

This time, seeming success! The temp gauge climbed off 90 and started drifting toward 120F.

Pretty soon though the high side started pinging again, the overflow tank overflowed, and as that happened the temp on the gauge started to drop. Down to 110. Then 100.

This time the fluid at the rad was a little warm. Luke, let’s say.

Back at the engine, everything’s boiling off. There’s a little oil leaking out from under the cam cover–maybe front main?

Green stuff running everywhere under the car from the overflow tank, but no real leaks I can see.

I don’t think the HG is blown–yet.

But not sure how to proceed. 

I thought maybe the rad cap was faulty–maybe it is. But it’s marked 1.3–which should be near 19 lbs pressure. The stock one is 16 lbs. So the new one that came with the rad would have to be wicked faulty for it to let leak-by & blow all that coolant into (and out of) the overflow like that….

It might be the stat is stuck. I tested it before installing it but that was a few months back and it set dry after that, so maybe?

But the real issue seems to be that the engine is getting hot enough to puke hard out the top hose while no other coolant anywhere in the system–much less where it needs to be, just above the thermostat–is above beer temp. 

Damndest thing.

Maybe someone who has worked radiators and stuff can set me on the right path.

edsnova2014-07-04 20:39:39

[Peter C. King]

 

Ed,

 

It sounds as if you still have air in the system. The trick is to bleed it. You may wind up with a bleed valve at the high point once you figure out where that is.

 

Air expands as it warms up. Water/antifreeze does not expand as much. As the engine begins to warm the air pushes water out of the overflow and sucks water back in as it cools and contracts. It sounds as if the air is in the engine. Is the thermostat on the block? It’s usually high on the block. In that case I would remove the thermostat and fill the system until water reaches the thermostat. Then replace the thermostat, fill the hose leading to it and top off the radiator.

 

That you are beginning to see temp on the gauge says that the waterline in the engine is going up.

 

Ideas:

 

1. Fill the system with the nose up so that the radiator is really the high point. 

 

2. Remove the thermostat, replace the hose and use a garden hose to see if I you can flow water through the engine from the in hose at the radiator. If the out hose burps air keep the water running until no more air escapes. Then button it up and see if that fixed the problem.

   

3. Smell the water coming out of the overflow for an exhaust smell. There’s still a chance that you have a head gasket leaking into the cooling system.

 

BDriver

 

 

[Ed Service]

Like BDriver wrote,

  Another thing, you should not be using straight anti-freeze!  This is another place where more isn’t better. 50/50 cools much better and flows better in your system too.

[Royal]

Ed, never owned a Subaru, but I feel your pain.  

I would

Put it in the driveway

Drain antifrz

remove the thermostat

Jack front end way up

Remove hose from radiator 

Jury rig some method of attaching garden hose directly to the hose going to the engine

Force flush with garden hose on full cycling the water on/off/on/off for at least 2 beers worth. Try this also against the normal direction of coolant flow.

I wish you luck. 

[edward ericson]

Thanks, guys.

Yeah, I’m going to need a bunch of bleeders, looks like. One on the rad top hose, one on the heater core exit (the high point), one each on the pipes as they go over the axle. Maybe one on the heater hose on its way out of the block too.

Looks like another project.

FYI, I did fill the block from the top to its high point–or pretty near–with more or less a 50-50 mix. The stat is on the bottom on this car. That’s the weird thing. 

BTW, I took a reading from the ECU when she was running. Got 0 trouble codes.

[Paul Mossberg]

Keep at it Ed. You’ll get this done!

By the way Roy…I love the way you keep time! “…for at least two beers worth….” Priceless!

Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster

If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)

[edward ericson]

OK, ordered five bleeder valves and a substantial amount of rigamorole with which to install them. Maybe $120 worth all told and now awaiting shipping. 

I will also need the muffler guys to weld a bung on one of the pipes they bent for me.

I will also need to drill and tap the Suby water neck I cut way back when, as that’s the high spot on that side. Thinking I may need to get an aluminum welder involved in this business, but I might try to get away with an epoxy job. It’s going to need a 1/8 npt thread for the bleeder. 

If all goes as now planned I will end up with five bleeder screws in the system:

1. at the top hose into the rad

2. at the top (outlet) from the heater core.

3. at the top heater hose outlet from the engine (which goes to the heater inlet)

4. at the return side rad hose where it goes over the axle.

5. at the main coolant outlet on the engine (which is higher than the axle-over pipe).

Should be done in a few weeks.

Today it is 73 degrees and sunny in Joppa, MD, and I am very sad to be sitting in my windowless home office ordering these parts instead of galavanting about the countryside in my car.

If I had foreseen this scenario last year as I was planning this caper, I would not have started the job.

edsnova2014-07-05 12:17:55

[Peter C. King]

Ed,

 

You engineered a liquid cooling system into an air cooled car. That is quite an achievement. So it has a few air locks in it. They are not hard stops. You are almost there.

 

Congratulations,

 

BDriver

 

P.S. Be careful of which epoxy you use. Most soften at 140 degrees. There are high temp products. Look at Liquid Metal.  

 

[Dale Schumacher]

Ed,
Just keep at it – baby steps – I am with you – July and 80 degrees and low humidity here as well and installing engine tin for my engine re-install. You are not the only one missing great weather.

[Ed Service]

Shouldn’t be that hard to get the air out. Are you sure you have the water flowing the right way through the rad?  Unless there is a compression leak putting air into the system it should burp itself once you get the engine block totally full.  Have you tried running it without the rad cap on? sometimes they need to operate without any backpressure until they get the air all purged. 

[edward ericson]

Thanks, Eddie. Yeah It’s flowing the right way–or it’s set up to, anyway.

And I did try it without the cap the first time and she got very belchy. I know that’s how it usually works. But that first try, I was getting so much violent purge on the high side that I could not keep up with the hose water.

There was no sign of the stat opening either. 

And that makes sense, since there was no pressure in the system and no way to get the coolant to flow into the heater core circuit, where it could trigger the flow event I still await.

Again–I can’t stress this enough–the Suby system uses the thermostat to determine when the coolant will go back into the engine, NOT, as with most other vehicles, to determine when it’s too hot to do any good and so must be allowed to flow out of the engine and into the rad.

It seems like a subtle difference, but in practice it makes it hella harder to get this rig flowing at normal temp this first time. 

Seems the pump is always pushing coolant out, pressurizing it even as it’s getting hotter.* But the thermostat has no interest in allowing any back in until the coolant hitting it from the heater core circuit reaches about 162 degrees. 

That’s what ain’t happening, for whatever set of good reasons.

*It is not insignificant, I think, that the stock Suby’s high side is opposite the side where the radiator cap and overflow are located, so that any burping has to flow sideways through the rad before manifesting itself, much more cooly, and calmly, under the cap. The stock Suby also has a built-in bleeder valve right next to the high side inlet. By contrast, the Honda rad that I’m using sees the high-side flow come in about five inches to the left of the cap, and of course the direction of proper flow is down, which is the last place the stuff wants to go when it’s hot. Especially when the thermostat is closed. 

[Ed Service]

Maybe try operating it without the thermostat until you prove that the engine is in good condition?

  I own a 2012 Subaru Outback and am somewhat familiar with how it works. Thermostats on the suction side are a lot more trouble to get purged properly!  I am a heavy duty mechanic at my day job so have considerable experience making things work. ( I work for Kubota)

[Montie Henderson]

Just a thought here, has anyone thought about how strong the water pump needs to be.  It may not be able to push the coolant the distance.   Maybe adding a 12 volt bilge bump from a boat in the system (or at least to get the air pumped through). When we put a Ford Cortina engine in a Baha bug (30 plus years ago) we mounted the radiator as part of the rear bumper.  Not the best look but it worked.   You might run a pressure test (cold and hot) front and back, I’m not even sure who could estimate the amount of pressure needed for the time and distance needed.  Do we have any engineers or physicists’ in the group?    

I’m not a pro-mechanic or anything, just thinking out loud or maybe I’m .

[Royal]

Montie,  I believe that you are on the right track, but there are too many variables and unknowns to help a physicist or engineer solve the problem.  In addition to the problem of long pipe runs into a non-non-subi radiator, the thermostat blocks all flow until the engine is fully warmed.  In my post above, I suggested using a garden hose to eliminate the possible problem of the Subi’s water pump not having enough head pressure….hoping that we could say what difference, at this point, does it make?

But, the thermostat poses a restriction to flow.  I suggested drilling the thermostat with a 1/8″ hole to allow some coolant to pass.   Or, how ’bout using a time-release pill to temporarily hold the thermostat open until the system is full of coolant.  (I’m beginning to think that Ed put Beano in the system on his first fill attempt.):P

[Author]

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