'83 Overheating and idling rough

83TercelSR5 · Post by **83TercelSR5** » Sat Jun 30, 2007 2:26 pm

I just bought a '83 SR5 a week ago and I have a couple problems.

1.) The biggest issue is that the temp gauge has been going to above red for the last couple days and it show's that the car is overheating really fast (like after 5 miles of driving. the fluid level in the resevoir is fine and there is never any smoke or steam or anything and the engine doesn't seem particularly hot but I don't know much about cars. Some people have told me that its probably the thermostat which is a cheap easy fix but i'm wondering if it could be something else. There does seem to be some coolant in the engine compartment coming from somewhere but again, the levels are fine. Could the radiator not be pulling coolant from the resevoir? The level doesn't seem to ever change. also on the top radiator hose leading to the engine there is a plug like thing right before what I think is the thermostat area (it is green if that helps) i don't know what it is but some of the tiny little conection wires on the top of it are broken so could that be causing some problem?

2.) It was running fine when I bought it but idling rough. It will idling around 1000 but drops down to 500 on and off and acts like it is going to stall. It's not a huge deal but I'd like to getting running smoother.

I tried searching the forums but didn't really have any luck. Thanks alot for your input!

neonsport · Post by **neonsport** » Sat Jun 30, 2007 2:48 pm

Since this car is new to you, replace the thermostat first. Buy one from the dealership; aftermarket ones are hit and miss at best. I've never had an aftermarket one work more than a season or two in the Tercel, and a factory one will likely last you as long as you own the car.

Replace your radiator cap. If the seal is bad, it can leak coolant and keep the radiator from pulling coolant from the reservoir.

While you're at it, flush and refill the cooling system. Don't use Dex-Cool or similar coolant. Make sure the lower radiator hose doesn't collapse while the engine is running at higher RPMs (like on the highway).

If the Tercel has the original radiator, it is likely at least partially obstructed. I replaced mine with an aftermarket unit that came with my parts car about 3 years ago. Since then, my Tercel hasn't run over about 1/3 temp even on the hottest day, sitting in traffic.

That's the problem with buying a 24 year old car. You have to start from scratch as far as knowing what maintenance items have been taken care of, and how well they were done. The good thing is that it's a Tercel. Once you've got everything working well, it'll likely work well for years.

83TercelSR5 · Post by **83TercelSR5** » Sun Jul 01, 2007 9:35 pm

So I actually just found that there is a coolant leak but I'm not sure where it is coming from. I added coolant and the car doesn't overheat at all but it definately is dripping from somewhere. It's not from the radiator or the hoses. It actually kinda seems like it might be coming from under the water pump but I can't really tell. Does anyone have experiance with that sealing stuff you pour in the radiator for small holes? I figure I should try that first. Hopefully my water pump isn't cracked or something.

Also can I just use water straight instead of coolant? I know it doesn't have the lubrication but I only plan on having the car for a few months.

Thanks!

GTSSportCoupe · Post by **GTSSportCoupe** » Mon Jul 02, 2007 12:35 am

83TercelSR5 wrote:So I actually just found that there is a coolant leak but I'm not sure where it is coming from. I added coolant and the car doesn't overheat at all but it definately is dripping from somewhere. It's not from the radiator or the hoses. It actually kinda seems like it might be coming from under the water pump but I can't really tell. Does anyone have experiance with that sealing stuff you pour in the radiator for small holes? I figure I should try that first. Hopefully my water pump isn't cracked or something.

Also can I just use water straight instead of coolant? I know it doesn't have the lubrication but I only plan on having the car for a few months.

Thanks!

Definitely don't use the coolant leak sealing stuff. I've only heard bad things about it. It can plug-up the coolant passages through the engine's head, and cause more damage than it fixes.

I think straight water would be ok for a few months, but I wouldn't recommend it for long. Just don't do it during winter if you live in a cold area (where it freezes).

takza · Post by **takza** » Mon Jul 02, 2007 5:33 am

If the rad cap is bad or the hose to the overflow is blocked...you won't see a low level unless you take the rad cap off.

Try tightening ALL hose clamps on the front of the engine?

Warm it up from cold to where it is a little under normal on the temp gauge...shut it off...then use a flashlight to find where the coolant is leaking?

If you keep overheating it...the head gasket or head will go...

Typrus · Post by **Typrus** » Mon Jul 02, 2007 2:00 pm

If it looks to be from under the water pump it very well could be the water pump itself. One of the weep holes indicating a fried bearing. They aren't expensive and aren't hard to do, if thats what it is.

Addsome lube additive to your straight water at least. I'm pretty sue they make an additive fo coolant to boost lubricative properties.

jetswim · Post by **jetswim** » Mon Jul 02, 2007 5:14 pm

Also, look for vacuum leaks! A big cause for rough idling.

mightyterc · Post by **mightyterc** » Tue Jul 03, 2007 9:09 am

Firstly replace the thermostat, and get those wires checked out.

That seal stuff is called chemiweld. Do NOT use it, as already said, it can block up your head, and the youve got a huge problem.

If you can, get the system pressure tested, and that will tell you how much of a leak you have. Hopefuly its just a lose hose or radiator cap.

Post by **Petros** » Tue Jul 03, 2007 8:02 pm

GTSSportCoupe wrote:
Definitely don't use the coolant leak sealing stuff. I've only heard bad things about it. It can plug-up the coolant passages through the engine's head, and cause more damage than it fixes.

I think straight water would be ok for a few months, but I wouldn't recommend it for long. Just don't do it during winter if you live in a cold area (where it freezes).

This is a myth, and an oft repeated fear. The sealants work fine for limited problems. there is nothing in a cooling system that is small enough for a sealer to plug up. Many new cars come from the factory with cooling system sealant since small leaks can often be difficult to find. They will not seal a bad hose or rubber seal (at the water pump shaft), they will not seal a head gasket, and they usually will not last that long. But to temp fix a small leak, the radiator sealants are fine. I have used them many times to get home and put off doing a permanent fix.

If your water pump seal is bad (coolant will drip out under the water pump pulley), you have to replace it, the sealant will not work. Water pumps are inexpensive and easy to replace if you have the knowledge and the tools.

Yes, and water makes a perfectly good coolant, I have used it for many years for summer driving (it actually cools better than anti-freeze). Do not use tap water, it has too many minerals you will ruin your radiator. Use distilled water from the market. In the winter months you need coolant or you risk damage to the engine in freezing weather (I have done that too).

good luck.

keith · Post by **keith** » Wed Jul 04, 2007 7:01 am

it actually cools better than anti-freeze

Thats another myth. Water has properties that should make it better, but water has a very high surface tension and its bipolar. A small amount of antifreeze breaks the surface tension and greatly increases its ability to absorb and radiate heat.

Pure water with aluminum is not a real good idea either. It worked with cars that had all iron blocks and heads with brass freeze plugs and copper radiators.

83TercelSR5 · Post by **83TercelSR5** » Thu Jul 05, 2007 6:52 pm

Thanks for all the info guys. I just hard a parts place in Sandy, OR order me a water pump and it was only like $28 which seems pretty cheap. I've never worked on cars so this will be my first job. It looks like a pretty basic job, is that true?

Unrelated question, I was trying to replace the fuel filter and was having a hard time getting the hoses off. are there any tricks for getting hoses off easier?

Thanks again!

tercel4wdrules · Post by **tercel4wdrules** » Thu Jul 05, 2007 7:38 pm

I also went through the same problem when I was replacing the hoses that go to the fuel filter. They simply would not come off, so I took a blade and cut them off and that saved the day without damaging anything. I just wish I would have done that when I first realized I couldn't get them off.

splatterdog · Post by **splatterdog** » Thu Jul 05, 2007 8:11 pm

I would also be prepared to throw a timing belt kit at it too. It will be off for the pump job. Also there is an o-ring seal between the pump housing and the front of the block that usually doesn't come with the pump. Easiest thing is to go straight to Toyota for that one.

Remove and install the whole pump assembly with the heater hose pipe attached as well. Gasket removal and placement is much easier on the bench. remove only the 12mm head bolts and the one 10mm that secures the dipstick and one 12mm holding the pipe to block. Don't forget to plug the dipstick hole too.

Pull the lower hose with the engine hot to drain(thermostat has to be open to let anything below the head out) and pull the radiator. They couldn't be any easier to pull and it really opens things up.

If you plan on keeping it I would also put cam/crank seals in too. Those were the biggest oil leaks on both of mine.

Finally. I see no one has mentioned checking the cooling fan. A quick test to see if the fan still works is to pull the fan switch connector on the bottom of the rad with ignition on. It should run.

Don Jorgensen · Post by **Don Jorgensen** » Thu Jul 05, 2007 8:26 pm

I've read several suggestions that may work for an emergency or temporary cooling sytstem short fix but you have to fix the problem.

First off the cooling system has to be pressurized to increase the boiling temperature. Antifreeze and pressure raises the boiling point beyond 212 degrees farenheight. About 10# pressure increases the boiling point to about 225 degrees farenheight. Running with the cap loose keeps pressure from building so the engine can keep coolant flowing through the system but also allows the system to push out because there are areas where coolant passes some hot surfaces above 212 degrees which will boil and push out the loose cap eventually leaving you without enough coolant passing through the system.
Keith makes good points about the advantage of antifreeze over distilled water.
There are no substitutes for properly cleaned surfaces, gaskets and compounds to seal bypasses and thermostat housings.
Petros makes some good points about these stop leak applications.

The hose removal from the gas filter is cronic to most hose removal. Unless you want to replace the hose, I suggest first giving the hose a twist with a pliers after you have moved the clamp out of the way. Then you gotta twist and pull as opposed to twist and shout. Most of the time you will prevail but wear gloves because about the time the hose will come loose, you will get the satisfaction of jamming your pulling hand across or on something sharp.

I wish I had access to a forum like this 40 years ago when I was under the panels of my first car, a 1936 Chevrolet Master Deluxe 2 door Sedan. So many things to learn the hard way.

Don

takza · Post by **takza** » Fri Jul 06, 2007 4:36 am

83TercelSR5 wrote:I've never worked on cars so this will be my first job. It looks like a pretty basic job, is that true? Unrelated question, I was trying to replace the fuel filter and was having a hard time getting the hoses off. are there any tricks for getting hoses off easier? Thanks again!

MOST of these "jobs" seem easy when you read the manuals and look at the pictures...but you soon find that the real world of old rusted/corroded parts and solid physical reality is usually a little different. My self seems to think these jobs will be easy...but I always say to my self...hey dummy...watch what the **** you are doing...or you'll THINK the job is "easy" before it's over.

Just had this proven AGAIN after getting into a rear brake job where the first order of business is to get the damned drums off...got into this casually...not remembering that in some cases...you get one chance to get it right...or you end up facing a mess. Because I wasn't watching my Ps and Qs as they say...I ended up having to make a brake drum puller to get the first one off. The second one I did using the screw holes in the drum...the right way...and even it wasn't easy.

So...NO JOB IS EASY...until it's over and you've driven the car for a week. ONLY THEN....you can get online and tell someone that the job is a piece of cake.