Should resovoir tube be on top position of rad fill tube?



Yesterday I completed the rad. Swap however I believe I put the resovoir tube on the steam tubes position?


Here’s a exploded view of a LT1 mine is LS1 but am thinking these tubes share the same position. Could this interfere w/ filling the rad.?


Here’s my plan cruise around a bit w/ tap water maybe 30 miles or longer it’s not gonna freeze for a few weeks.

I believe the whole cooling sys holds 15 quarts for automatic trans cars. I was able to pour 1gallon, 3 an half quarts of tap water into rad. Running her for 5 minutes w/out the rad. cap letting sys. Burp out trapped air.

On all previous rad. Flushs I’ve only used 1gallon of dexcool then filled w/ tap water.

Since I was able to pour in almost 2gallons it mite be a good idea to add 1 an half gallons of dexcool then fill w/ half gallon of tap water that combined w/ blocks gallon would be the proper mixture of coolant correct?



Edit: 25 years ago I Bypassed the transmission in rad. For external B&M super cooler.

IIRC I plugged the rad trans lines BC of the power steering cooler which is now history, so there’s realy no need to plug these ports any more correct.

Please advice an Thanks

 

Yes, the reservoir tube goes up top. The engine will overheat without this correct.

The radiator cap shuts off the connection to the overflow reservoir (so the system stays pressurized) and opens up to let excess pressure escape to the bottle and let fluid back in as things cool and a vacuum develops in the system.

If the tubes are reversed, then the system will not pressurize. In that configuration, the radiator is open to the atmosphere through the overflow reservoir. (Just like it would be if the radiator cap wasn't on at all.)

I recall that when I did my last super flush, just over 1 gal of fluid was in the radiator and 1 gal sat in the passages and galleries of the engine block.

 

I thought the thicker steam tube looked a tad differnt, will reverse the tubes before I cruise around.

are you saying the whole cooling sys. only holds 2 gallons? BC IIRC on previous flushs I'd pour only one gallon in rad. then fill the rest of it w/ water probley another gallon.
how much fuild goe's in the resovior? I'll use the dip stick to fill it up. BTW that failing coolant level sensor went back on easy enough w/ rad removed an appeared intact where I doubt it caused any leak as previously thought.thanks for advice.

 

The owners manual has us at almost 3 gallons and I forgot about the overflow tank: (So, just over 1 gallon from the radiator drain, just over 1 gallon comes out from draining the block, and the remainder is in the overflow tank.)

 

since swap I've cruised around on a couple 10 miles trips. here's the level at rad. after upteen flushs I still have small specs of brownish crap on the rad. lid image of level.you can see the fuild is still nasty. I should have cleaned the inside of the upper an lower rad tubes there was a bit of brownish crap I did clean a little but not thoroughly.


I may have added to much tap water into reservoir the lower large section is completely filled it's filled right to the bottom of the fill tube.

I've decided to use one an a half gallons of the preston orange dexcool

plan to pour in fuild:. pour the first gallon directly into empty rad.which in theory will mix w/ the gallon already in block.
then mix the half gallon w/ distilled water an continue to fill rad. then the remainder of this into reservoir.

 

$4 will get you an antifreeze tester, which will show you the concentration on your mix. No need to guess anything with that very inexpensive tool.

If you don't want to go the route of a cleaning agent and full flush, I would just steal the wife's turkey baster, suck off that crap that is floating on the top of the coolant and wipe the neck with a towel. After doing this a few times, it might clear up.

 

excellent advice as usale. I've already stolen a turkey baster years ago, I did replace it though.yes I'm observing the GM mud specs on my brand new cap also floating on the rad. fill tube.

I tightened the new rads cheesie hard plastic pet ****/drain just hand tight. poured half a quart of tap water in to make sure drain was tight.
proceded to pour in one gallon, an one an a half quarts of consentrated orange dexcool
which filled the rad up to just below the resovoir pickup tube.
the last quart of dexcools was w/ engine running for around 15 minutes burping air bubbles.

so according to my calculations I need to add this half a quart for total of one an half gallons half the whole cooling capisity.
since I haven't added anything to resovoir I'll add this half quart to resovior? then fill rest of resovoir w/ tape water.

I poured 2 quarts into resovior which filled it to above its full level. I believe the resovior holds one an a half quarts but haven't completely confirmed this.


I'm not sure exactly how to fill the resovior evidentiality fuild is constantly being sucked in an out of this resovior. never realty paid much attention to reservoir level
like the dipstick has a cold level maybe a half quart or more then a hot level maybe quart an a half? please advice. an thanks

I've been wanting the antifreeze tester my new 05express 3500 RV van came w/ the green antifreeze which I should have flushed out a couple years ago. I didn't bc it looks newish.

 

I wouldn't worry too much about the "hot" level, it's always going to change depending on just how hot the coolant is.

What really matters is the cold level. Once all the air has been burped from the system, and the engine has been allowed to fully cool (overnight), that's when you want to set the fill point to the cold level.

What I have learned from many, many drain & fill cycles with the stock radiator is that when you first refill the radiator (after completely draining it), you'll want to set the level in the overflow bottle to roughly the "full hot" point (when the engine is cold). This is because there will still be air in the system, so you want some extra coolant capacity so that there will be fluid to replace the air that is purged when you run it the first time (if you run the overflow bottle empty, then you'll just suck more air into the system and prolong the purge process). After the engine has been fully heated (including circulating coolant through the heater core) and allowed to fully cool down (overnight), you'll want to check the level again. It will likely be below the "full cold" point, so fill it back up to the "full cold" level. You'll want to check it once or twice more after a full heat up/cool down process just to make sure that the level is steady...and when it is, then you'll know that all the air has been fully purged.

I always use the pre-mixed 50/50 coolant so that I don't have to worry about blend ratios. Otherwise, you might have to keep draining and refilling to get just the right blend without being under or over filled.

 

Excellent advice above, which follows my experience. ^ Running the engine won't get the air bubbles out, but running the system through several heat-up/cool-down cycles will. Monitoring that "cool" level will tell one where the system is and the antifreeze tester will confirm what part (antifreeze or water) needs to be added to make up the difference.

 

I haven’t driven her since filling the rad. All I’ve done is run engine w/out the rad. Cap an observed the air bubbles, did this for about 15 minutes an she’s still burping a few bubbles.

Haven’t added anything to the now empty resovior. Except the little bleed over though resovior tube when filling rad. so I will check dipstick I'm not expecting much probaley less than half a quart.

Is the reservoirs dipstick lower level reading the hot?

I’m thinking it must be the lower reading bc the rad has sucked the needed fluid to satisfy the sys.?



When you say to fill to “when you first refill the radiator (after completely draining it), you'll want to set the level in the overflow bottle to roughly the "full hot" point “



Is that like one quart of the premixed antifreeze to empty resovior?



As far as the mix ratio goe’s I counted the block as one gallon an rad. As one an a half gallon. Resovior as 2 quarts total cooling sys.3gallons (will premix resovoir). I think the upper level on dipstick is 2 quarts where I can premix that for proper ratio.I’m assuming the rad,s antifreeze will mix w/ blocks water?thanks for advicing.


will the remaining bubbles actuely bleed off though the resovoirs bleed off tube? also what do you think about the green antifreeze in the van like if I test it an its w/in acceptable range just leave it or change to the dexcool orange? thanks.

 

Yea, the top of the radiator will trap those air bubbles and as the coolant in the system pressurizes and expands, it will "burp" the gas out through the overflow bottle. This will keep going once you put the cap on - the pressurized system will get any last bits of gas out of the system and flow them to the radiator. Under pressure, more gas could accumulate there than the expansion of one heat/cool cycle can deal with. No big deal - over several cycles, the system will naturally push gas out and suck fluid back in. (from the bottle) Taking measurements at the dipstick at the bottle will give the best information and taking a peek under the cap once everything is cooled will allow you to keep an eye on any crud.


Normally, the fluid level in the reservoir will go up when hot (fluid expands and some gets pushed out to the bottle) and will go down as it cools. (fluid contracts, creates a vacuum in the system and sucks fluid back in from the bottle) HOWEVER, as the system is working air bubbles out of the system after a flush, you may not notice a change because it is pushing air out instead of fluid. Checking the "cool" level after a cool-down will tell you where you really are. Don't be surprised if the level keeps going down after a few cool-down cycles. Its probably not a leak but a signal that more air is being worked out of the system.


When the system is cold, fill to the cold line. Per the process above, you will need to come back and make up a little more after additional heat/cool cycles as air works out of the system.


Its all out-of-my-science. I'm not sure anyone has a perfect measurement of what is in the block because emptying it involves taking a shower in coolant. (its a very sloppy thing) lol Getting the $4 antifreeze tester is the sure-fire way to know where things are. Its an amazing thing and probably the least expensive tool we can by for a car these days. (The antifreeze companies must be giving us a break on it because they know it will help them sell more product.)


Yes. The steam tube, (at the top of the engine) and air rising to the top of the liquid in the (relatively) calm environment of the radiator captures the air right at the siphon tube for the overflow bottle and that's how it gets out.


You should be all good. May be just rinse the tester out with fresh water when going between the coolant types.


If you like tools and want to really nerd out with this, you can get a refractometer from Amazon for $25. Its more precise, but a lot harder to use. (Its also important to pick out a model with the right scale for what you are measuring. ...and then read the correct scale when you are taking the measurement.) Ethylene Glycol is what is in the car. The other chemical is for other types of coolant.

 

^ Great answers above. I agree with all of it.

It might take quite a few heating/cooling cycles to get ALL of the air out. Sometimes I'll still see minor drops on the overflow dipstick (maybe 2-3 ounces, which is about one or two rectangles on the stick) even after ~200 miles and a dozen heating/cooling cycles.

On the coolant ratio/mix, I honestly don't know why anyone ever fights with this problem. Even if you don't want to spend slightly more money per ounce for the premixed coolant, you can just pre-mix the concentrated stuff yourself before you pour it into the radiator. It's just so much easier that way. Only exception would be if you're adding to a system with a current ratio you want to change, in which case you'll need to add pure water or pure antifreeze to adjust the blend. I guess that might be the case here if you were doing a water flush and didn't want to go through the whole process of draining the block again.

Refractometer is a great tool. I have a couple of really old ones from the '60s, from a relative who used to work for Caterpillar and kept them when he retired. They were very high grade for their era and still work great. Much more precision than I would ever need for home use, but might as well use what I have.

 

my resovoir is basicely empty.
I'm a bit confussed RPM WS6 says to fill resovoir to roughly hot full which is the lower section of dipstick.

When the system is cold, fill to the cold line. Per the process above, you will need to come back and make up a little more after additional heat/cool cycles as air works out of the system. what am I missunderstanding here?

 

I'm not sure what you're looking at, but the "full hot" level marking is higher than the "full cold" level on that dipstick. The level will always be higher when the engine is hot, hence the factory marking being higher for the "hot" position.

 

If the reservoir is cold empty, that's a sign that air is still working out of the system. Add more to the cold level on the dipstick.

The dipstick should look like this: (without the crud on it - It should say "Full Cold" below the first rib and "Full Hot" above the second rib)

 

OK I see the hot level it is the higher position. this is where I roughly fill to before driving. then start heat cycleing an checking the level.
one more thing the first engine mod was air lid an ported throttle body. when I did the throttle body I removed the coolant line. IIRC the throttle body is plumbed inbetween the rad lower overflow an the steam tube under the intake manifold.
is the throttle body coolant line mainly for northern cold climate cars?
thanks

I see the two levels. since I haven't added anything to resovior I fill the premix to the hot before driving.

here's my DS still has the Lucas stop leak from the power steering cooler leaking into the cooling sys,BTW What is this plastic piece I circled?
thanks

 

The throttle body coolant line connects to the port on the radiator just below the overflow tube. This is the same port that also connects to the steam tube, so you would just bypass the throttle body portion if you didn't want coolant circulating there. I think this system just prevents icing of the throttle blade in very cold weather, probably not a concern where you live. Lots of folks delete it, I don't think it's ever really a problem.

That plastic piece circled above doesn't look like anything stock. None of my four 4th gens have ever had a piece like that anywhere near that wireloom area. I see you have an aftermarket cable there, probably for an audio system, so maybe it was a leftover from when that was installed. It looks like some sort of a battery terminal cap or something such as that.

 

Yea that's for cold weather climates, definitely not Florida..

Even when it's in the 20's here it's not enough to freeze the Throttle Body.

 

It also looks pretty clean/new. I'm thinking its road debris shed off from a lesser make of vehicle that may have gotten kicked up in the engine compartment.