Overheating problem

I have a 65 riviera that runs great but over heats. I have change the thermostat, radiator, water pump, double checked the timing, and switched to a electric fan. The car won't heat up at idle but as soon as I drive it, it gets hot. I was wondering if anyone else has ran into this problem. I'm leaning towards it being a head gasket but it's not blowing steam out the pipes. I'm going to try a block test sometime this week to see if it picks anything up..

Thanks Casey

Hey Casey.,

Let's start with some basic questions and I'm sure our forum friends will have more.

New or used radiator? Has the engine ever been bored out? Does it run hotter at higher speeds or heats up when in traffic? Does it have a clutch fan and has that been checked or swapped? There's another recent thread that covers lot of these variables, meaning there can be many things to explore and then rule out... Plus maybe it's one cause or a combo of causes. Knowledge leads to discovery, I guess.

It's a new radiator I went from stock fan to electric fan with no change the motor is stock bore I believe.

it gets hot after driving it I can let it idle for ever and won't overheat.

Thanks Casey

There's an identical thread to yours on here. The solution for that gentleman was a new radiator. Browse the threads and you'll find it. Read it and you'll identify with what you're posting. Then you'll see his solution.

Ed

Already read it and changed everything with no luck..

I have seen this problem due to omitting the thermostat, heard of the problem running a 160 thermostat moving the water too fast to pick up the heat or not enough time in the radiator to dissipate the heat. Long shot the thermostat was left out or defective stuck open all the time? 60 over can and will run hot. Do you have a fan shroud? My buddy and I are both 2nd Gen owners and have been through our share of nailhead over heating issues and in more than one case there was no rhyme or reason. Are you allowing the air gap in the radiator for expansion? These cars will puke coolant when over filled, do you have a temp gauge and does the car run poorly or does it just seem or show symptoms of being hot like purging? The temp gauge on Goldie reads 230 on a hot day and I am sure she is 190 maybe 200 but not 230 it is just the variant in the gauge. New radiator cap?

Thanks, I have a new radiator and cap. I'm running a fan shroud with a 160 thermostat. I did notice that the water looks like a river flowing. The car get to about 220 and will purge some water but I do have the system full I will try and lower it some. Should I try to run a 180 thurmostat? The car runs great It just get hot after driving it around but I can let it idle and it cools back down..

Thanks Casey

Hi Casey, Remember that for every pound of pressure in the system your boiling point of 212 increases 3 degrees therefore with a 15lb cap x 3 per pound is 45 degrees above the 212 for a total of 257 degrees, then your coolant will add another 20 degrees for a total of 277 degrees before your water becomes steam therefore not cooling your engine and causing a problem .... as long as it is liquid you will not damage the engine so at 220 you are not in danger but watch it and become concerned at over 250 or 260. Look at you mechanical gauges they show 280 degrees at the top not like the OLD CARS without a pressurized system showing 212 as boiling which is just water without pressure. Manufacturers dropped many of the temp gauges because customers became alarmed when they saw 230 or 240. Keep an eye one it and talk to your radiator man to ease your anxiety. Good luck Paul

Check out this website ........... http://www.aa1car.com/library/overheat.htm good luck, Paul

Did you check to make sure the brakes aren't dragging? Can you stick your foot out the door on a level surface and make it roll in neutral?

Bernie

Thanks for the help.. I did a block test and it came back good so no blown head gasket. I was wondering if a stuck heat riser could cause it to over heat just noticed that mine is stuck shut.. Well I can't move it by hand should I be able to?

Thanks Casey

Ok I finally figured out my overheating problem my new radiator was clogged already.. I was in denial that was the problem. Is there anyway to clean the cooling system out I'm running a panty hoses to catch the stuff and its alot. Is there any way to help it? Iv tried a flush but didnt seem to help. I think the motor sat for 10 years with just water in it.

Thanks Casey

Take the rad out and have it professionally rodded out. My 2 cents...

I got the radiator cleaned, its in the block that I need to get the stuff out of.

OK, now I understand. I'll defer to the more knowledgeable folks on this forum. How many miles on the block, to the best of your knowledge?

http://www.evaporust.com/evaporustcsc.html?gclid=COXwy4i09sACFQto7AodgVIANw

Thank you Ed ill give it a try.

Thank you Ed ill give it a try.

There is a way to diagnose a clogged radiator in ten seconds with no guesswork. You diagnose

this problem with a laser temperature gun. You can buy a laser temp gun that you can point a laser at anything and it will tell you the temperature of the object where the beam is hitting it. I keep one in my toolbox and it is a lifesaver on diagnosing overheating problems. If you point the gun at a clogged radiator, you will find that it is very hot at the inlet at the top hose, but there will be cold spots further down, sometimes room temperature if it is really clogged. A good radiator that is flowing will be somewhere between

180 and 155 throughout the core no matter where you point the gun. By the way, an engine that only overheats going down the road and not at idle is a clogged radiator about 95 per cent of the time in my experience. The other five percent is usually a water pump impeller problem.

Edited September 23, 2014 by Seafoam65 (see edit history)

Also consider your elecric fan. The factory fan with clutch and shroud is actually very effective and pulls a good amount of air especially if you get a HD fan clutch. Electric fans do work if set up right, but many times they are not.

Electric fans can sometimes work, but they're only over compensating for the original problem.* You have to remember that in there hey-day these cars ran fine from the factory with the correct temp thermostat, water from the tap, and the stock radiator. There's no reason they can't do the same now. As Winston says "find the problem and get it fixed." There's a hidden problem somewhere that needs to be found. I like the idea of the laser temperature gun.

Rebuilt water pumps can be a problem right out of the box if the rebuilder has taken short cuts and "smoothed" the impeller to look good rather than replacing it. If the blades have been shaped to look good they'll just cause the water to cavitate in the pump rather than circulate it. A stuck hot air choke flapper in the exhaust system will force hot air through the intake rather than through the tailpipe. Like Jim Cannon says, make sure that you have a quality clutch fan, not one of the cheap ones. Is your a/c condenser blocking air flow to the radiator? If you've done the basics, then it's time to dig deeper. Sometimes you just have to swallow your pride and break down and consult a professional. Tim at Macek's Automotive in Merriam, KS knows my cars better than I do.

Ed

*A guy goes into a men’s wear shop to purchase a new suit. There’s not much of a selection but he finds one he likes and wants to have it altered. The sleeves are too long, the pant legs are too long and the waist is too large, and the lapels are too wide. The shop owner doesn't have an alteration shop but he also doesn't want to lose the sale.

The shop owner pulls the sleeves up and tells the guy to press his arms against his chest. He has the guy hold up the waist with one hand, and pulls the legs up and has the guy hold his knees together. He then adjusts the lapels and has the guy hold them in place with his chin.

The guy walks out of the shop and passes a couple of elderly women. One says to the other, “Look at that poor man, so deformed.” The other lady replies, “Yes, but doesn't his suit fit him well.”

Edited September 23, 2014 by RivNut (see edit history)

i figured out what my over heating problem was it was a bunch of stuff in my cooling system that clogged my new radiator. i went and had the radiator cleaned out and now it wont brake off 170 but im running a pantyhose to catch the stuff before it goes into the radiator.. this is what i got after driving it around for a hour yesterday..

i need to find a way to clean this stuff out of it.. or ill just keep checking it after a few miles guess it can only get better lol

The Aussies have a device for that. It's spliced into the upper radiator hose. I was sent one by a friend but have since discarded the package so I don't know the name of it.

Ed

The only way to get all that sediment and scale out is to remove all the core plugs from the sides of the block. Dig it all out and flush with a water hose and strong stream. Then run it without a thermostat and keep cleaning out your panty hose filter. You won't get a strong flow from the water pump with the stat in place. Drain and flush the coolant several times until it drains out clear. Your heater core also needs to be back flushed.

I will try that this weekend.. I want to pull the freeze plugs out And try to flush it out threw them. I'm just glad I'm in the right direction I haven't been able to drive it much with the overheating problem.. Thanks for the help

Taking the freeze plugs out to drain the block is not going to completely drain the block. You can't just "pull the freeze plugs" you have to drive them out then drive new ones in (if you can find the correct size) plus they're terribly difficult to get at with the engine in the car. Besides that, the bottom of the freeze plug sits higher than the lowest level of the water jacket where all of the sludge and sediment settles. The only way to get all the water out by removing freeze plugs is to tilt the engine 90 degrees sideways, both ways. The lowest parts of the water jacket are the two drain holes on either side of the block. They're not very large so a good sized piece of junk will stop the water flow. Your best bet is to try and "cook" some of the scale, rust, and sediment loose using a chemical bath, and draining it through the water pump. Then when it looks fairly clean, reconnect everything chemically clean it again but this time drain it through the drain holes in the block. You'll need to be able to tip the car front to back in order to get all of the water and junk out of it. Running a car without a thermostat won't get it hot enough to cook everything loose unless you do something else to make it run hot, like take off the fan and block the radiator.

Ed

Thanks for the help, I will give it a try I drove it around for a few hours today and there was alot less stuff in it. I'm going to try and pull the lower drain plugs.

http://www.ebay.com/itm/111470767957

http://www.ebay.com/itm/111470767957

Tom would you recomend this after a rebuild.T.N...

Tom would you recomend this after a rebuild.T.N...

Hi Nuge,

Not necessarily but obviously it cant hurt anything. I WOULD definitely recommend a fresh radiator after a rebuild. I wouldnt call it cheap insurance as the cost to recore a radiator has escalated but a fresh rebuild will want to run hot for awhile and nothing will ruin a tight engine faster than overheating.

Tom

Hi Nuge,

Not necessarily but obviously it cant hurt anything. I WOULD definitely recommend a fresh radiator after a rebuild. I wouldnt call it cheap insurance as the cost to recore a radiator has escalated but a fresh rebuild will want to run hot for awhile and nothing will ruin a tight engine faster than overheating.

Tom

Will do Tom,after cost of rebuild now is a good time to do so.wanted to recore in the future anyway.thanks for the headsup-T.N...