1800cc Over-heating Problem

[V.T. Eric Layton]

Hello group,

I have a 1982 Subaru Brat w/ the 1800cc engine. A couple years back I was
having an intermittant over-heating problem. Unfortunately, I did manage to
overheat the engine to excess one day and ended up popping one of the head
gaskets and warping the head. I tore down the engine after that and did a
rebuild on it. The rebuild has only about 1,500 miles on it, but I'm again
experiencing the exact same over-heating symptom.

Here's what happens... in city driving, over a period of a couple weeks or
so, I will lose about 1 qt. of coolant from the radiator. However, in
sustained highway driving at speeds of 55-65 mph (3,000-3,500 rpm) the
radiator loses over 1 qt. after about 30 minute of driving. I've checked
this girl over from stem to stern. The only place that it's losing the
coolant is straight out of the overflow on the filler of the radiator
itself. There are NO other leaks. I've actually watched the overflow
belching coolant out while I was standing there.

I know what you're gonna' say... change the cap! Well, that's been tried 2
or 3 times now. I even spent $18 on a OEM cap from the local Subaru dealer.
That didn't help either. She's great for knockin' around town, but I can't
trust her on the open road for long trips. This little truck was my mother's
at one time. It was her pride and joy. The thing only has 70K miles on it,
no rust, no dings or dents, etc. It's a nice little truck. That's why I took
the time and the expense to rebuild the engine and keep the thing. I have
two other trucks and a motorcycle, so none of them get driven excessively.

Anyone here with some suggestions or ideas, I'm open. I've discussed this
with a couple "master" mechanic friends and they're stumped. The last
suggestion I received was to have the radiator flushed out, but EVERYTHING
was flushed and cleaned just 1,500 miles ago, when I rebuilt the engine.
Like I say... any suggestions will definitely be considered by me. Maybe
someone else out here has had this same problem in the past.

Either post here or reply via email -- (e-mail address removed)

Regards,

 

[pheasant]

Hello group,

I have a 1982 Subaru Brat w/ the 1800cc engine. A couple years back I
was having an intermittant over-heating problem. Unfortunately, I did
manage to overheat the engine to excess one day and ended up popping
one of the head gaskets and warping the head. I tore down the engine
after that and did a rebuild on it. The rebuild has only about 1,500
miles on it, but I'm again experiencing the exact same over-heating
symptom.

Here's what happens... in city driving, over a period of a couple
weeks or so, I will lose about 1 qt. of coolant from the radiator.
However, in sustained highway driving at speeds of 55-65 mph
(3,000-3,500 rpm) the radiator loses over 1 qt. after about 30 minute
of driving. I've checked this girl over from stem to stern. The only
place that it's losing the coolant is straight out of the overflow on
the filler of the radiator itself. There are NO other leaks. I've
actually watched the overflow belching coolant out while I was
standing there.

I know what you're gonna' say... change the cap! Well, that's been
tried 2 or 3 times now. I even spent $18 on a OEM cap from the local
Subaru dealer. That didn't help either. She's great for knockin'
around town, but I can't trust her on the open road for long trips.
This little truck was my mother's at one time. It was her pride and
joy. The thing only has 70K miles on it, no rust, no dings or dents,
etc. It's a nice little truck. That's why I took the time and the
expense to rebuild the engine and keep the thing. I have two other
trucks and a motorcycle, so none of them get driven excessively.

Anyone here with some suggestions or ideas, I'm open. I've discussed
this with a couple "master" mechanic friends and they're stumped. The
last suggestion I received was to have the radiator flushed out, but
EVERYTHING was flushed and cleaned just 1,500 miles ago, when I
rebuilt the engine. Like I say... any suggestions will definitely be
considered by me. Maybe someone else out here has had this same
problem in the past.

Either post here or reply via email -- (e-mail address removed)

Regards,

Mebbe you've got a few plugged cores in the radiator. Sounds like my 86 GL
about 8 years ago, I flushed till blue in the face, and still overheated on
hot days with AC running. Was totally stumped, talked to my Scooby's big
job mechanic; he asked me when I'd last changed antifreeze, said Hmmmmmm not
sure. Suggested I replace the radiator, and bingo. No more overheating.
Guess that's what I get for not listening to scheduled maintenance
suggestions when it came to cooling system. I do now.

Mark

 

[Tony Hwang]

Hi,
Water pump? Chem flush of cooling system. Sure head and gasket is A-OK?
Rad. hoses in good shape?
Tony

 

[S]

Hi VT, All!

Hello group,

I have a 1982 Subaru Brat w/ the 1800cc engine.

Check for an internal coolant leak where the intake manifold connects
to the cylinder head(s), and/or at the head gaskets. Coolant entering
the intake passages or combustion chamber here is more or less
undetectable unless real severe (you can smell it in the exhaust
sometimes, may give plug tips a yellowish tint), but leaks in these
areas, especially at the head gasket, can over pressurize the coolant
system, causing the radiator cap to barf coolant.
If that's all nice -n- tight, I'd get a nice clean junkyard radiator
and try that. Oh, I assume you've checked that _both_ fans work, the
fan temp switch on the radiator is OK, and the thermostat is opening
as promised . . .

ByeBye! S.

Steve Jernigan KG0MB
Laboratory Manager
Microelectronics Research
University of Colorado
(719) 262-3101

 

[V.T. Eric Layton]

Hey Folks,

Thanks for the quick responses. Yep, everything was flushed less than 1,500
miles ago, when I did the rebuild. As to whether the head/gasket are all
right, well... there seems to be no eveidence of burning of coolant in the
combustion chamber. There's no evidence of burned coolant in the exhaust.
I've been advised that a faulty head gasket can create excessive pressure in
the radiator, but this is the exact same problem this engine had prior to
the rebuild. I'm leaning toward a radiator problem. Amateurish flushing
attempts by me previously probably served no purpose. I'm going to end up
taking it to a radiator specialist and let them "rod" it out properly and
see if that will alleviate the problem. Thanks for the helpful advice all.

Regards,

 

[Rick Courtright]

attempts by me previously probably served no purpose. I'm going to end up
taking it to a radiator specialist and let them "rod" it out properly and
see if that will alleviate the problem. Thanks for the helpful advice all.

Hi,

While rodding out the radiator MAY do the trick, it's very likely you're
throwing good money after bad. Before taking it to the shop, why don't
you get a hold of the folks at www.radiator.com. Ask what they have for
your car, especially if they have a double row core. Their prices are
surprisingly good, their service also good (although I'd suggest if it's
practical that you pick up your new radiator at a local warehouse so you
can match it with the old one right off. It took three different catalog
numbers to get the one that fit my car best.)

Many here on the NG have reported poor results with cleaning clogged
Subie radiators, which is why I suggest you investigate a brand new one.

Best of luck,

Rick

 

[Edward Hayes]

Rodding out radiators on modern cars is almost useless today as the material
is too thin. Manufactures had to do this with all the polution stuff
requiring 195-205 degree stats to get max cooling. Ed

 

[Bill Putney]

Hi,

While rodding out the radiator MAY do the trick, it's very likely you're
throwing good money after bad. Before taking it to the shop, why don't
you get a hold of the folks at www.radiator.com. Ask what they have for
your car, especially if they have a double row core. Their prices are
surprisingly good, their service also good (although I'd suggest if it's
practical that you pick up your new radiator at a local warehouse so you
can match it with the old one right off. It took three different catalog
numbers to get the one that fit my car best.)

Many here on the NG have reported poor results with cleaning clogged
Subie radiators, which is why I suggest you investigate a brand new one.

Best of luck,

Rick

I 150% agree with the Rick's and other's recommendations here to
*replace* the radiator. BTI (Before The Internet - in my life anyway) I
learned this the hard way too. I messed around for 2 years convinced
that if I cleaned the radiator enough, it ought to clear it out. By the
time I figured out that it wasn't getting any better, I had to replace
the heads.

My experience and that of countless others says that cleaning/rodding -
either DIY or by a shop - does very little if any good on these
radiators. The tubes are so small on the inside that the slightest
buildup will clog them with no chance of clearing, PLUS the external
fins corrode away and/or fill totally with sand and/or bugs so no air
can get thru to do its job. Reversing that is impossible (or at least
not worth the time that it takes even if you *could* be even marginally
successful at it).

Replace the radiator - radiator.com - and have done with it.

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")

 

[SuperPoo]

Replace the water pump also. Pump failure is common in your vehicle and will
give very similar symptoms to what you are reporting. (Cools better at low
speed/rpm)
Not to say it is not your radiator but if I were betting a buck on this I
would bet on the pump.

Steve

 

[V.T. Eric Layton]

Pump is brand new... less than 1,500 miles. It was replaced when I did the
rebuild last Spring. It's relatively easy to replace, but I think I'll try
the rad first.

Thanks...

 

[Ed Fortmiller]

Went through many overheating problems with my '82 1800 engine a few years
ago. Replaced the head gaskets and other stuff. Still didn't fix the
problem. Replaced the radiator and that fixed the problem.

--
Ed Fortmiller | (e-mail address removed) | Hudson MA
*
* To avoid getting a lot of SPAM junk mail, I have altered my REPLY-TO
* address. PLEASE remove the leading "RUBBISH" from my REPLY address.
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[SuperPoo]

Well if the pump has only 1500 miles on it, that blows my theory. Good thing
I did not bet the buck.

Steve

 

[V.T. Eric Layton]

Well, you know, Steve... that's why they call it "gambling" and not
"winning".

Later...

 

[V.T. Eric Layton]

Wow, Ed! That makes me much more confident about the radiator change out.
Sounds like you went through all the same crap I went through. I couldn't
call Radiator.com today... it was a bit of a hectic day. I'm gonna' try to
give 'em a holler tomorrow.

Thanks,

~Eric

 

[Ed Fortmiller]

Wow, Ed! That makes me much more confident about the radiator change out.
Sounds like you went through all the same crap I went through. I couldn't
call Radiator.com today... it was a bit of a hectic day. I'm gonna' try to
give 'em a holler tomorrow.

I'm not sure how good/bad aftermarket Subaru radiators are as I have never
used one of those.

Sometime ago I needed to replace my heater core in my '82 so I bought an
aftermarket unit. When I pulled out the original Scooby one it had more fins
and more tubes. Put the aftermarket one in and it never functioned as good
as the original Scooby one. On cold winter days the interior of the car
never got real warm.

--
Ed Fortmiller | (e-mail address removed) | Hudson MA
*
* To avoid getting a lot of SPAM junk mail, I have altered my REPLY-TO
* address. PLEASE remove the leading "RUBBISH" from my REPLY address.
* Any Email sent to the address without removing "RUBBISH" will
* automatically be discarded without me even seeing it.

 

[V.T. Eric Layton]

Well, I had the choice between OEM and aftermarket when perusing the
Radiator.com website. I chose the aftermarket due to its cheaper price and
the fact that it had a lifetime warranty. As far as heater cores go... well,
here in Tampa I could light a couple matches in the cab of the car and that
would heat sufficiently for any kind of Winter weather we get down here...


Later...

~Eric

 

[Rick Courtright]

I'm not sure how good/bad aftermarket Subaru radiators are as I have never

Hi,

I'm not sure about other vendors' products, but I went with a two-row
core from www.radiator.com last summer on the advice of several folks
from the NG. Recently, my auxilliary fan died, and I haven't had a
chance to replace it. But the two-row radiator actually runs cooler with
one fan than the factory unit did with both (and barely warmer than it
did with two fans.) This is in temps of 100F+ here in SoCal.

HTH,

Rick

 

[Bill Putney]

Hi,

I'm not sure about other vendors' products, but I went with a two-row
core from www.radiator.com last summer on the advice of several folks
from the NG. Recently, my auxilliary fan died, and I haven't had a
chance to replace it. But the two-row radiator actually runs cooler with
one fan than the factory unit did with both (and barely warmer than it
did with two fans.) This is in temps of 100F+ here in SoCal.

HTH,

Rick

Same here - on my (previously - now sold) '86 turbo wagon, it had one
belt driven fan and one electric. I actually was able to leave the belt
driven fan off, and the temp gage would stay in the middle on the
hottest day of summer with the a.c. going full blast.

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")