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Old 05-06-2016, 01:17 PM   #3876
Gregski
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Re: Restoring Rusty

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Originally Posted by Valarius_Starchaser View Post
maybe I haven't been following along well enough but have you replaced your radiator cap? what psi is it rated at and would a different psi help and what is your actual coolant to water ratio have you measured it??
sure enough my old radiator cap leaks like a sieve, does not hold pressure at all
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Old 05-06-2016, 01:22 PM   #3877
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Re: Restoring Rusty

so bought a new one, $5 bucks

tested it as we test all parts new or old here at Suburbs Garage Inc. and it tests good

took the truck for a test drive with the new cap, and results: no change, truck runs just as hot

remember all the cap does is increase the boiling point do to the added pressure, it does not effect how hot your engine runs, so the result was expected, but its still good to have a proper working cap
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Old 05-06-2016, 01:23 PM   #3878
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Re: Restoring Rusty

side by side for prosperity

the new cap was designed by someone who actually owned and operated a vehicle cause it has two edges for you to grasp whilst screwing or unscrewing it, unlike the original which was perfectly round and nothing to hold on to, win, win
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Old 05-06-2016, 09:02 PM   #3879
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Re: Restoring Rusty

I know in our race cars we only ran water. Then sometimes we'd run Water Wetter which did help especially on the fifty lap races of stop and go. Eventually we went to an electric fan from a Volvo and that cooled the engine nicely. As for the bypass hose if you can't find one start looking at 3500 trucks with the 454 engines in them. I had to replace that stinking hose on our work truck. Good luck and get to cracking.
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Old 05-07-2016, 07:56 AM   #3880
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Re: Restoring Rusty

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the new cap was designed by someone who actually owned and operated a vehicle cause it has two edges for you to grasp whilst screwing or unscrewing it...
This is because, by leaving those little ears off, GM was able to save a small fraction of a penny on each gross of caps. Then, by the time the savings were spread over the entire production run, GM was able to keep some $87.73. The shareholders should have been very pleased.

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...in my case first the door panels had to pass the scratch test...

...take a green scotch bright pad and a bucket of lightly soapy water and wash/scrub them as best as you can

give em another finger nail scratch test if they still leave a mark...
I've read through this thread a couple of times now and it's like reading a book. I hope that I'm not wrecking the thread somehow but, considering that this previous quote is genuinely from THIS very thread, I figured that I will take a chance.

Ok, so I'm really unenlightened when it comes to this stuff. I have a couple of questions - what is it that I'm trying to scratch and how do I know when the panels are ready to accept the paint? I took the panels off of my truck, cleaned at least one of them up really well with Simple Green because it was what I already had in the garage. In those areas where the panel, the one that I cleaned, is NOT chalky, my fingernail doesn't leave any sort of mark. But in the chalky areas, YUP! I do leave a mark. When I clean it a second or third time, there is no difference. What's up with this? Can you help?
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Old 05-07-2016, 09:27 AM   #3881
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Re: Restoring Rusty

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This is because, by leaving those little ears off, GM was able to save a small fraction of a penny on each gross of caps. Then, by the time the savings were spread over the entire production run, GM was able to keep some $87.73. The shareholders should have been very pleased.



I've read through this thread a couple of times now and it's like reading a book. I hope that I'm not wrecking the thread somehow but, considering that this previous quote is genuinely from THIS very thread, I figured that I will take a chance.

Ok, so I'm really unenlightened when it comes to this stuff. I have a couple of questions - what is it that I'm trying to scratch and how do I know when the panels are ready to accept the paint? I took the panels off of my truck, cleaned at least one of them up really well with Simple Green because it was what I already had in the garage. In those areas where the panel, the one that I cleaned, is NOT chalky, my fingernail doesn't leave any sort of mark. But in the chalky areas, YUP! I do leave a mark. When I clean it a second or third time, there is no difference. What's up with this? Can you help?
the scratch test does just that it determines if the panel is ready for paint, we are not saying all panels can be saved, or painted only the ones that pass the scratch test, hope that helps, your panel may be passed it and ready for the trash can
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Old 05-07-2016, 09:37 AM   #3882
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Re: Restoring Rusty

pressure tested the cooling system next, and heard a hissing sound by the inlet hose (top driver side) there appears to be a tiny crack/leak there and another tiny one somewhere towards the passenger side on the bottom, not show stoppers, but this do place the radiator on the Parts Replacement List
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Old 05-07-2016, 09:42 AM   #3883
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Re: Restoring Rusty

Gentlemen I'll be brief:

NO THERMOSTAT

NO PROBLEM


DISCLAIMER: We are not going to run without one, this is just a great clue.

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Old 05-07-2016, 10:08 AM   #3884
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Re: Restoring Rusty

did you try a high flow thermostat yet?
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Old 05-07-2016, 10:27 AM   #3885
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Re: Restoring Rusty

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did you try a high flow thermostat yet?
I have not, not yet, thank you for the suggestion, to be honest whichoo I have not heard of a high flowing unit, is that what they mean by a 180*F vs the stock 195*F? or is it something totally else
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Old 05-07-2016, 10:46 AM   #3886
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Re: Restoring Rusty

It has a larger area for the water to flow through so is not so constricted,they are a little pricey $15 or so
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Old 05-07-2016, 09:27 PM   #3887
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Re: Restoring Rusty

After seeing that, I for one, would condemn the Duralast Thermostat. If the engine is that cool without a thermostat, I would have to think the AutoZombie part is not working correctly. It may be opening enough to not overheat, but not opening enough to get the temp where it needs to be.

I would try a better part. Maybe a Stant? Maybe a 160 or 185 degree just for some wiggle room.
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Old 05-07-2016, 09:32 PM   #3888
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Re: Restoring Rusty

Get a 180º AC-Delco thermostat.
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Old 05-07-2016, 09:46 PM   #3889
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Re: Restoring Rusty

Stick with the stock 195, but get a quality unit. You want the engine to come up to normal operating temp. This helps a bunch of things, among them lubrication.
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Old 05-08-2016, 09:53 AM   #3890
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Re: Restoring Rusty

first I plan to test mine

then I intend to step up to a name brand one, and test that one before even installing it

next I think we may need to run a 180* or even a 160* F with the Vortec heads, only testing will tell

and finally theres that high flowing thermostat option, who knew this little guy had so much impact, (what a control freak) ha ha

as an FYI I will save drilling holes in the Thermostat as the last resort, lol
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Old 05-08-2016, 12:04 PM   #3891
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Re: Restoring Rusty

What kind of head gaskets did you use?
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Old 05-08-2016, 12:19 PM   #3892
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Re: Restoring Rusty

High flow thermostats would be the units like the 195°F Stant 45359 SuperStat

To regulate coolant at roughly 195°F the thermostat needs to be fully open at 200°F and closed somewhere around 180°F.
You don't want to run 160°F thermostats in a daily driver. Fuel mileage and engine longevity will suffer. Normal coolant temp should run between 200°F and 230°F. This will keep the engine oil above the boiling point of water to boil off any condensation and unburnt fuel to be exhausted out through the PCV system... These temps will still keep the oil below the temps where it'll start to burn and coke up the engine and the combustion chamber will run at a fairly efficient temp.

The 1970's OEM temp gauge is a poorly calibrated guide at best. Only slightly better than a warning lamp because it gives you a heads up before you get to OMG IT'S TOO HOT. Most aftermarket gauges are little better.
If you really want to know what temps the engine is running you'll need a good quality infrared thermometer. The $30 Lowes, Home Despot, and Horrible Fright units don't qualify. You're going to spend over $70 for a decent one. My old Fluke cost over $130
There really is no reason to trust a 42 year old nail head sender. If it's a new unit it's likely either badly matched to your gauge or, if it's a Letric Limited unit, defective.
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Old 05-08-2016, 12:36 PM   #3893
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Re: Restoring Rusty

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What kind of head gaskets did you use?
these are the cylinder head gaskets I am using GM Chevrolet Performance part number 10105117 as per the GM turn key engine build specifications
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Old 05-08-2016, 01:23 PM   #3894
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Re: Restoring Rusty

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Originally Posted by hatzie View Post
High flow thermostats would be the units like the 195°F Stant 45359 SuperStat

To regulate coolant at roughly 195°F the thermostat needs to be fully open at 200°F and closed somewhere around 180°F.
You don't want to run 160°F thermostats in a daily driver. Fuel mileage and engine longevity will suffer. Normal coolant temp should run between 200°F and 230°F. This will keep the engine oil above the boiling point of water to boil off any condensation and unburnt fuel to be exhausted out through the PCV system... These temps will still keep the oil below the temps where it'll start to burn and coke up the engine and the combustion chamber will run at a fairly efficient temp.

The 1970's OEM temp gauge is a poorly calibrated guide at best. Only slightly better than a warning lamp because it gives you a heads up before you get to OMG IT'S TOO HOT. Most aftermarket gauges are little better.
If you really want to know what temps the engine is running you'll need a good quality infrared thermometer. The $30 Lowes, Home Despot, and Horrible Fright units don't qualify. You're going to spend over $70 for a decent one. My old Fluke cost over $130
There really is no reason to trust a 42 year old nail head sender. If it's a new unit it's likely either badly matched to your gauge or, if it's a Letric Limited unit, defective.
Agreed on keeping the 195 for the reasons stated. Also, oil viscosity varies with temperature, and you want to get the oil up to operating temperatures so it's fluid enough to provide good lubrication by getting into all the nooks and crannies.

The Harbor Freight infrared thermometer unit I have has actually been pretty accurate when checked against more substantial units. May vary unit to unit, but mine at least seems OK.

Agreed also on the sender units with one exception. American Autowire makes a 1513321 correct substitute, with the resistance curve matched to the 1978 and earlier gauges. Any other substitute will not match the gauge.
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Old 05-08-2016, 06:21 PM   #3895
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Re: Restoring Rusty

We used to use an infrared unit from HF while checking tire and rotor temps on the race car before switching to probes. The HF worked fine and was well calibrated against the probe long acre unit we used.
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Old 05-09-2016, 08:31 PM   #3896
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Re: Restoring Rusty

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Originally Posted by rusty76 View Post
We used to use an infrared unit from HF while checking tire and rotor temps on the race car before switching to probes. The HF worked fine and was well calibrated against the probe long acre unit we used.
I've had two. They were both pretty dodgy. Must be luck of the draw. Gloom despair and agony on me...
The Fluke was pricy but It's been great since day one.
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Old 05-09-2016, 09:05 PM   #3897
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Re: Restoring Rusty

so tested the 1999 Suburban Valucraft thermostat rated for 195* F

it also don't open until 205*F
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Old 05-09-2016, 09:09 PM   #3898
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Re: Restoring Rusty

more importantly gauges showed up, we got a brand new Summit brand water temp gauge in green and a matching oil pressure Summit gauge also in green (we'll deal with that one later)

naturally it came with a 1/2" NPT adapter (would it kill em to send the 3/8ths?)

so it will be mounted in the water outlet initially than transplanted to the intake manifold driver side
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Old 05-09-2016, 09:10 PM   #3899
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Re: Restoring Rusty

What's in the big white box?

patience ODBI
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Old 05-10-2016, 12:03 AM   #3900
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Re: Restoring Rusty

alright so equipped with the brand new digital water temp gauge and sending unit it was time to go back to square one and install the 195* F thermostat back in to see how hot actually the truck runs, and so we did and guess what the guage never read above 199* F and we drove it hard for 30 minutes like we do in all our tests

by the way I love this new gauge it says a number and the word TEMP what more do you need, it is absolutely brilliant

but wait does it show the display in 7 different poser colors, absolutely NOT, and we love it that much more for it

the gauge took about 10 minutes to install and 9 of those minutes were spent looking for long enough cables to install it in the cabin, lol

black to truck ground

red to switched 12 volt power

blue to sending unit

purple (is a mickey mouse wire for dimming the gauges) no thanks for now

so while driving ie moving we were reading 194* F and while stopped at a red light we were reading 197* F
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