might be running HOT!

[gonzo]

i finally got around to driving my 72' dime after getting some of the bugs worked out. noticed the temp was about half way with a little street driving, so decided to get the Radiator flushed and cleaned. after driving it more temps just kept rising! checked the Thermostat on the stove and drilled a small hole, still same result. installed a electric fan and had same result. drained and refilled with cap off, water didnt seem to move and needle very close to the "H" so i removed the Stat temp went down to half and up to about 3/4.

 

bought a new Stat and a IR temp gun. at idle very close to the "H" around the "P" in TEMP. checked the the whole engine bay with temp gun Rad, Head, Block, Hoses, Oil Pan and Exhaust. biggest number i got was 170* F, (except Exh@ 328*F). Cap off water never move or spilled over was even able to put my finger in the Rad water without getting burnt (not recommended).

 

Could i just have a Bad Temp Gauge? am i missing something? am not loosing any water at all and car feels good.

 

Hopefully i can get this fixed and make the Eagle Rock Swapmeet

[Zeusimo]

I Would Try Running A Cheap Aftermarket Gauge To Be Sure

 

Everything Sounds Right

 

My Temp Gauge On My 610 Is Blown...

So Maybe They Loose Accuracy After A While???

 

Maybe There Is Stuff In The Block

My 610 Had TONS Of Acorns In The Block

[DAT510]

Head might be plugged?

If you can put your finger in the rad, wouldn't that mean that the stat isn't opening or water isn't getting to the stat?

[gonzo]

am also thinking Accuracy might be off.

 

how would i check if the head is plugged?

 

i took it for a quick run on the Freeway, got back home checked temp with gun all over and got 180*F as the highest. took Rad cap off with no over spill and water was nice and calm!

 

could it also be the Temp Sender on the inlet gone bad? i noticed the wire on it is newer like if somebody replaced it.

[DAT510]

Check the temp of the stat housing and the top part and compare temps.

 

I'm not sure how you would check if the head is plugged while it's on the head...

maybe take off the stat housing off of the head.. But not while the head is hot!!!!

[gonzo]

on top of the Stat Housing i get 160*-170*F. on top of the Rad i get about 158* and bottom about 125*.

 

am gonna see if i can find a cheap Temp Gauge somewhere.

 

also there is a line hooking up the stat housing to intake to outlet with water flowing.

[DAT510]

I was just concerned about you saying that the Rad water is calm, and that you could stick your finger it... Is this while running or immediately after a drive?

Cause if the rad water isn't hot after a drive, then the stat might not be opening up, but if water flows to the intake mani, then it's def not plugged.

Yeah might be your gauge lol

[banzai510(hainz)]

sand the contact that goes to the sender.

 

If you have another housing(w/sender) you could swap it out instead .

Its EZer than trying th etake the sender out and brecking the whole housing.

Find the gasket from housing to the head

 

 

make sure the lower water hose isnt collasping when motor is reved up

 

 

You think the gause if OFF????? Your gas gauge accutrate also??????? If gas gauge off then its a volt reg proplem in the instrument panel.

[ggzilla]

Do you have the L20B engine? There was a service bulletin about this.

[gonzo]

Don't get me wrong, the water in the rad is hot when I put my finger it's just doesn't seem 220+*F redline hot.

 

It's got an L16.

 

It looks like the Fuel gauge is working fine so far. I don't have another housing or sender so am just goin to sand the one I have.

 

Could it also be a bad water pump? It looks brand new but I know that doesn't mean much.

[datzenmike]

#1 It obviously hasn't boiled over so can't be that hot. I've had water in the block boil while the rad temp was cold. When it boils the pressure will blow water out the rad cap.

#2 The temp readings you got with the IR gun are normal... could be a bit warmer but ok.

 

Cheapest easy thing to do is replace the sender.

 

The resistance inside the sender lowers as the temp goes up so a bad connection/corrosion would read cold(er) not hot... but won't hurt to clean the connection..

.

[kelowg]

Id pull out t stat and drive it. Then at idle, cap off. See if water is flowing thru rad. Might need to drain off some water to see it moving

[gonzo]

Am goin to replace the sender, I'll try that first. I already took the old one out cleaned it up with sand paper (wasn't really dirty) but didn't make a difference.

 

I've already tried it with stat off and water seems to be flowing. Can't really tell how fast it is or do I know how fast it should be!

[datzenmike]

Here...

 

 

Run up to temp and use a resistance meter on the sender. If within the graph the gauge is suspect.

[gonzo]

Datzenmike,

 

I want to give this a try. I think I got a meter somewhere in the garage.

 

How would I hook it up to the sender and do I have to set it at a certain setting?

[ggzilla]

Ohmmeter, connect black wire to bare metal of engine block. Connect red wire to the temp sender .

[gonzo]

well i gave it a try with 2 different Ohms tester. the first one is a Harbor Freight hand held electronic digital. the second one is a Sears Automotive Analyzer from 70's or 80's.

 

both Meters read @ 45-46 ohms. testing them on the bare metal and negative post on the battery. on the old Sear's i adjusted the ohms by touching the cables and setting it @ 1 ohm and kept testing it after disconnecting, hopefully thats the correct way. inside the car it was reading right at the center of the "P".

 

according to the chart, that seems like the right Temp for a hot and humid day in the Valley. so would buying a new sender and gauge be the best way to make sure its running correct?

[ggzilla]

Nope, that won't help.

 

Your sender is reading 45 ohm, but what is your guage reading at the same time?

[gonzo]

I disconnected the wire on the sender when I did the test. The gauge inside the car read @ center of "P" before and after the test.

 

Should I have left the wire to the gauge connected? And if so, is it a good idea to hook up the meter from cold till hot and keep an eyes on the ohms to see any changes?

[ggzilla]

From your description, sounds like there is no problem. When Sender is 45 ohms, Gauge is centered. That's just about right.

 

Unless "center of P" means something other than center of gauge.

[gonzo]

By Center of "P" is we're the needle reads in the word "TEMP" on the gauge on top like in the Table Datzenmike offered. In othere words the needle is close to the "H" on the hot side of the gauge (under the word temp). According to the table it should be on the "T" on the word "TEMP"

 

Maybe that makes more sense. Am goin to connect the meters this morning as the engine is cold and see if I get a different readings as the Temp warms up and changes.

[gonzo]

i did a test this morning with engine cold. it was reading @ about 200ohms. with the fan removed and Electric fan OFF and car completely Hot it got to the lowest reading, @ 30ohms. on the gauge in the car it was right before the RED. according to the table it should of been about half way! there was no boil over on the Rad and car sounded fine at idle.

 

i think am going to Auto Parts store and see if i can get a Temp gauge and test it again!

[datzenmike]

My 620 and 720 truck and both my 710s read about 1/3 the way up the gauge. So about the E in TEMP. Never at 1/2 but always below. The gauges should be read as what ever is normal for your car and when it changes by going higher or not reaching your 'normal' range as possibly a concern.

 

When I was a kid everything was about cars and racing. Every race or dragster had gauges and idiot lights were considered a joke. This was through the 60s in the heyday of the muscle car era. People complained and looked for options like gauges for temp and oil pressure and the factory responded by including them in their cars. BUT these gauges mostly didn't have numbers so really what was the point? Well my guess is that they were concerned that owners would be alarmed by some of the readings. For example oil pressure can vary widely from cold to hot and sudden stops and very sharp cornering can cause the pickup to briefly suck air and drop pressure. A brief zero reading or falling gauge would freak-out owners. Temps I notice can climb above normal as the engine warms up but quickly settle down and run in their normal range. Both oil and water temp gauges are slow moving so that much of these extreme readings are not noticed. Numbers would only alarm most owners so a temp normal 'range' is used. As long as inside a small range everything is ok, outside... maybe it should start to be a concern.

[gonzo]

I sort of see what you mean. I want to have the peace of mind that I will shut my car off or at least cool it down before it over heats.

 

Well I bought an aftermarket gauge but the sender and adapter don't fit the stat housing and all sales are final on those products. While trying to connect it to the stock sender, the Radiator water finally boiled over then all the water got somewhat light brown. I turned on the Fan and it calmed down right away. I connected the Meter and turned OFF the fan and checked it again. It started to boil over at about 25ohms. Inside the car the gauge was on the RED. Also during all this you can see the water flowing.

 

It looks like the Stat is working and with the Ohms reading I got it opened at the right temp.

 

Maybe I can find the right adapter and still be able to use the new Temp gauge.

[datzenmike]

The brown is the boiling inside the block stiring up the rusty sediment. There are two small brass block drains, I think one on each side. You can remove and flush water through. Ideally a frost plug or two can be removed and a garden hose used to stir it up and flush it out.

 

The coolant area around the cylinders can get scary rusty and the scale drops off and collects in the bottom and acts like insulation. So always use and keep good quality anti-freeze in there.