Hey all! 

 

I have an '87 Subaru GL wagon, and have been having a couple of problems.

 

1. Overheating. This has been consistent for the past few months. I put in a new thermostat (then a better one because the Stant one was a POS), hoses, water pump and poured water through the cooling system. And still, when I'm cruising at 3,000 rpm, it starts to run hot. Especially now that summer is here. I can't really figure out what the problem is. The coolant looks clean and all… 

 

2. High idle. I thought this was causing the overheating, but that appears to be a separate issue. The high idle came after a 12-hour snow rally, and I thought I found a vacuum leak around the gasket where the EGR pipe attaches to the intake manifold. So I replaced the gasket. No change. I took the carburetor off multiple times to check that none of the screws holding it together were loose (I had rebuilt the carb last year). I checked the base of the carburetor, and the carb itself, for vacuum leaks by spraying carb cleaner around it. Nothing.

 

The difference came when I unplugged the idle stop solenoid. When it's plugged in, the car idles smoothly, but races. So I unplugged it and it runs like spoob, and even then still a little high. Honestly, I just need the thing to run well enough not to blow up until I throw in an EJ22 next month. I'm done spending money on gutless EA82s. But I'm getting a little help from a more experienced friend, so I'll have to drive it on the EA82 for about 250 miles.

 

Ideas, anyone?

 

Thanks, 

 

Ben

 

Can't help with the carb part, been too long since I had one.  The overheat.  Is it pushing coolant into the overflow bottle?  Is there air in the top radiator hose, even after a few full run / rest cycles?

 

From my experiences, EA82 + low coolant overheat = blown headgasket/s in no time.

I don't know if there's air in the radiator hose. How can I tell?

…and if there is air in the upper hose, what's the best way to purge it?

First, did you replace the thermostat with a OEM subaru one? Aftermarket ones are notorious for causing problems. Second, this could be the thermo sensor... I have heard of those things causing issues when they go out. 

 

Third...is the carb a hitachi? 

Pinch and release it quickly multiple times with a hand. Listen very close, you may hear air, gurgles, or just the jiggle pin in a good quality thermostat. If the recovery bottle and cap, no leaks, good head gsdkets, etc. Is working correctly, a few drive cycles will get rid of small amount of air.

A small amount of air is not the cause, it is a symptom. If the upper hose is mostly air, you won't hear gurgles or jiggle pin. In that case, open the cap and add coolant until full. Pinch the upper hose, with the cap off, air bubbles out, add coolant. When I deal with this kind of thing, I use water until I find the cause, unless it is winter.

First, did you replace the thermostat with a OEM subaru one? Aftermarket ones are notorious for causing problems. Second, this could be the thermo sensor... I have heard of those things causing issues when they go out. 

 

Third...is the carb a hitachi? 

 

Yes, it is a rebuilt Hitachi carb. I replaced the thermostat with the best one Napa had, but not an OEM subaru one (the dealership was having trouble locating the part).

 

Thermo sensor… Hmmm. What does that do, where is it, and could it be causing problems with the carburetor's idle stop solenoid?

If you haven't already, I would try adjusting the high idle screw on your hitachi (if you dont know where that is I can post a pic) 

Regarding the thermo sensor, or sometimes called a 'coolant temperature sensor', it it is located on the backside of the engine block, just below the intake manifold (although it might be different for EA82s, I have an EA81) It is almost always near the thermostat housing. It is the unit which tells you how hot your engine is, and I believe it also regulates other electronic things within your engine. (could be wrong about that) If it fails, it will give you false readings on your dash, and I have heard it can cause other electrical issues. Here is what it will look like out of the block:  https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcQDhzabWtxdzRTqYn7ceKAhDDyQEqiUHRSbIlSn7FvVk9vZLKyRag

and obviously, only the top part will be showing when its in the block.

They are pretty cheap usually, I just bought one from rockauto on sale for $8; because mine is 31 years old and will need to be replaced soon. 

 

EDIT: I forgot to address the aftermarket thermostat. As just about everyone on this forum that has had to deal with aftermarket thermostats  will tell you... they are bad news. And I would recommend that you find an OEM subaru one ASAP. Have you tried the online subaru store?

Edited May 13, 201510 yr by Sapper 157

The higher end Stant thermostats are good also. There is a thread about this. I've had no trouble with them.

If you haven't already, I would try adjusting the high idle screw on your hitachi (if you dont know where that is I can post a pic) 

Regarding the thermo sensor, or sometimes called a 'coolant temperature sensor', it it is located on the backside of the engine block, just below the intake manifold (although it might be different for EA82s, I have an EA81) It is almost always near the thermostat housing. It is the unit which tells you how hot your engine is, and I believe it also regulates other electronic things within your engine. (could be wrong about that) If it fails, it will give you false readings on your dash, and I have heard it can cause other electrical issues. Here is what it will look like out of the block:  https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcQDhzabWtxdzRTqYn7ceKAhDDyQEqiUHRSbIlSn7FvVk9vZLKyRag

and obviously, only the top part will be showing when its in the block.

They are pretty cheap usually, I just bought one from rockauto on sale for $8; because mine is 31 years old and will need to be replaced soon. 

 

EDIT: I forgot to address the aftermarket thermostat. As just about everyone on this forum that has had to deal with aftermarket thermostats  will tell you... they are bad news. And I would recommend that you find an OEM subaru one ASAP. Have you tried the online subaru store?

 

Yes, please show me where the fast idle adjustment screw is (although I've never had problems with it before, and nothing has been changed…I rebuilt the carb in November and drove it all winter without problems).

 

I put Napa's highest end thermostat in it, as the Subaru dealer in my area didn't have the part listed.

 

Thanks.

Anyone have any idea how to bypass it temporarily until my new temp sensor gets here? Nobody around me can get one for 3 days and I've gotta drive the thing, overheats after about 20 minutes..

Are you asking about

Anyone have any idea how to bypass it temporarily until my new temp sensor gets here? Nobody around me can get one for 3 days and I've gotta drive the thing, overheats after about 20 minutes..

Are you asking about a fan switch for your brat? This is a totally seperate issue and not likely related to this thread. Is /was the car equiped with a/c and dual fans? To bypess the switch on the radiator youll need to supply a new method of grounding for the fans. Be it a relay and switch, or just a heavy gauge wire run to the cabin and a 20 amp switch to ground. Flip on the switch after warm up. If your having trouble finding the switch there are other options. Ive found some aftermarket switches are normally closed or just stuck closed out of the box. Many other switches could likely fit the hole but finding the right temp, correct thread and similar connector would take alot of research.

 

Something like this would work ide still use a relay.

http://www.ebay.com/itm/Hayden-3653-Cooling-Fan-Control-/281481802148?hash=item41899f71a4&vxp=mtr

 

And this is very similare to factory with correct threads but the temp is low (stock is like 205 degrees turn on)

http://www.ebay.com/itm/181495142283?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

I forgot to ask,.did you try adjusting the idle adjust screw on the front of the carburetor? If you use a flathead driver and turn it to the left then it should slow your idle down.

Sorry if took me so long to upload this. Hopefully you have fixed the problem by now but in case you haven't here is the pic.

Is your fan turning on? Is there anything blocking air flow?