Coolant Level Anomaly

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Side note on Vaseline. I had two 2Fs and one 3FE motors rebuilt at an old, old machine shop where Vaseline was used as the assembly lube. Two of these motors have > 300k each on them indicating that Vaseline was a suitable assembly lube for the bearings.
back in the late 80's early 90's when building Rotary engines vaseline is what we used to hold all the corner & apex seals in place as well as the large O-rings etc during assembly. Worked a treat but made for a big smoke cloud on 1st startup which quickly dissipated.
 
So I finally got the new overflow assembly delivered today after having to pay an additional $68 in orange douche tax to enter the country.

Maybe this will fix the issue, or maybe not. In any case, it's nice to have clean and shiny new parts.

I will say that the new tubing fits substantially tighter than the 29 year old ones and is in much better shape.
Fingers crossed Jon!
 
I might've missed this but my assumption is that Jon has already revved the engine up to 2k+ rpm while watching for aquarium style bubbles in the overflow tank!
 
I might've missed this but my assumption is that Jon has already revved the engine up to 2k+ rpm while watching for aquarium style bubbles in the overflow tank!
See post #31.
 
Update:
I had to run a bunch of errands yesterday, so before I started I made certain that the new overflow bottle was EXACTLY at the FULL line and the radiator was filled up to the filler neck port.
Did a bunch of highway with lots of local streets mixed in, and of course some sitting in traffic.
Checked levels this morning and the overflow bottle was exactly at the full line and the radiator was up to the neck.

I spent some time going over the old overflow assembly and it all looks pretty solid.
At this point I'm going to call it good and chalk it up to old rubber??? Who knows.

HOWEVER, one thing that just popped into my head, while I was out yesterday I didn't have the heat on because it was the first warm day.
I'm going to have to run the same test with the heat on and see what happens.
 
Final update.
Ambient temps dropped 30F yesterday along with some snow flurries. Ran around with the heat on.
Checked levels this morning and all was good.

So basically I could have fixed this issue with $1.50 worth of new hose as opposed to spending $100+ on an entire new assembly.
However I will use a juicy rationalization that it all should have been replaced long ago and I was delinquent in my maintenance.
Yea, that'll work.
 
Glad you fixed it!

Semi related question as I’m also keeping an eye on my coolant levels after radiator change. Is it normal when the outside temperature dropped 10 deg Celcius since last time I checked, that I noticed less coolant in the overflow tank in the morning (I always check in morning). I know coolant contracts under colder temp but was still wondering if I get the right idea. So before going to inspect for a leak, I realised it could be temperature related, opened the radiator cap and found more coolant in the radiator than before, last time I did that exercise a few days ago, with warmer weather! So it seems more coolant has been going back into the radiator at it cools overnight, it definitely looks like what’s missing in the overflow (still at high) is in the radiator. Is this a rad cap thing, or normal with colder temps.

Just for my curiosity. Thanks
 
Glad you fixed it!

Semi related question as I’m also keeping an eye on my coolant levels after radiator change. Is it normal when the outside temperature dropped 10 deg Celcius since last time I checked, that I noticed less coolant in the overflow tank in the morning (I always check in morning). I know coolant contracts under colder temp but was still wondering if I get the right idea. So before going to inspect for a leak, I realised it could be temperature related, opened the radiator cap and found more coolant in the radiator than before, last time I did that exercise a few days ago, with warmer weather! So it seems more coolant has been going back into the radiator at it cools overnight, it definitely looks like what’s missing in the overflow (still at high) is in the radiator. Is this a rad cap thing, or normal with colder temps.

Just for my curiosity. Thanks

your radiator level should always be full, the overflow bottle will rise a bit after a drive as the coolant heats up and expands so it will push some out and into the overflow, but then as it cools, it will suck it back into the radiator. A ten degree change in ambient temp is not going to cause big changes in coolant levels in your overflow bottle.

If you've just replaced the radiator, you may still have air in the system, so the vehicle can "burp" these over time and your coolant level can drop. Did you try and bleed the system with the heater on and the cap off while refilling with a sealed funnel?
 
your radiator level should always be full, the overflow bottle will rise a bit after a drive as the coolant heats up and expands so it will push some out and into the overflow, but then as it cools, it will suck it back into the radiator. A ten degree change in ambient temp is not going to cause big changes in coolant levels in your overflow bottle.

If you've just replaced the radiator, you may still have air in the system, so the vehicle can "burp" these over time and your coolant level can drop. Did you try and bleed the system with the heater on and the cap off while refilling with a sealed funnel?
Thanks, yeah I did! But I also figured out the system could still be adjusting itself after a few heat/cold cycles (air pockets etc)

The coolant in the radiator a few days ago was a bit low (picture one) but I did not do anything to it. This morning it was higher like on the picture, and I have not added any coolant since then as mentioned.Overall level I would assume is the same as what I lost in the overflow (I am talking half a cm down) seems to have increased the level into the radiator.

So thought it could be the temperature, it’s not, gotcha. Maybe the system just adjusting, I’ll keep an eye on it and check both radiator + overflow each morning. Right now I dont have to add anything as it’s full in both.

IMG_7108.webp


IMG_7109.webp
 
if one can appreciate how clean that coolant look though, it was not a given considering what it looked like before. This is after a 400km drive post radiator + coolant hoses (incl PHH), thermostat and fan clutch change.
 
if one can appreciate how clean that coolant look though, it was not a given considering what it looked like before. This is after a 400km drive post radiator + coolant hoses (incl PHH), thermostat and fan clutch change.
The difference in level in those 2 pictures is about a tablespoon. Not an issue.
Coolant levels in the overflow will rise and fall with temperature as that is the nature of the beast.
I had a 30F drop in ambient temps yesterday and the level in the overflow was slightly below the full line. Again, to be expected.

The key is that the radiator remains full and that over time, weeks/months not days, there should be no coolant loss.
 
My 2 cents, for hose lubrication.

Vaseline, is petroleum based, it should not be used on rubber coolant hoses. For that I recommend Dow Corning 4, DC4, or any silicone based lubricant.

Cheers
 
The difference in level in those 2 pictures is about a tablespoon. Not an issue.
Coolant levels in the overflow will rise and fall with temperature as that is the nature of the beast.
I had a 30F drop in ambient temps yesterday and the level in the overflow was slightly below the full line. Again, to be expected.

The key is that the radiator remains full and that over time, weeks/months not days, there should be no coolant loss.
Thanks that makes sense. Temperature went back up to when I was checking a week ago and now coolant in overflow exactly at the same level than before, so it was the outside temperature as I thought. But got it shouldn’t pay too much attention to it on a daily basis, but feels good to see it back up just to make sure nothing was lost at least after my 700km drive.

Edit: For everyone to understand I am only checking the coolant that often because my engine recently overheated pretty bad and I was fearing a HG issue. In Australia the HG on the 1FZFE seems to be far less of an issue than in the US, have not really looked into why though, but still had to think about it. Looks like I dodged another bullet and she’s good for another thousand km 🤞🏽
 
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Thanks that makes sense. Temperature went back up to when I was checking a week ago and now coolant in overflow exactly at the same level than before, so it was the outside temperature as I thought. But got it shouldn’t pay too much attention to it on a daily basis, but feels good to see it back up just to make sure nothing was lost at least after my 700km drive.

Edit: For everyone to understand I am only checking the coolant that often because my engine recently overheated pretty bad and I was fearing a HG issue. In Australia the HG on the 1FZFE seems to be far less of an issue than in the US, have not really looked into why though, but still had to think about it. Looks like I dodged another bullet and she’s good for another thousand km 🤞🏽

I had a similar issue to you, and have basically been down the same path as you. New radiator, all new hoses, tracking coolant movement. After a full cooling system refresh, even trying to "burp" the system while refilling is hard on these engines, they will equalise after a few hundred kms of driving. You're doing the right thing by keeping an eye on it, and tracking any changes.
 
I think you made the right call. I replaced my overflow hose but now I keep looking at that hazy, foggy bottle. A new bottle just makes it that much easier to monitor coolant levels.
 
My 2 cents, for hose lubrication.

Vaseline, is petroleum based, it should not be used on rubber coolant hoses. For that I recommend Dow Corning 4, DC4, or any silicone based lubricant.

Cheers
Vaseline/grease is a goofy choice for sure. Antifreeze is pretty slippery. Smearing that on radiator/heater hoses works for me. Windex works well for sliding hoses on as well.
 
I'm late to the party but only checked out the thread because THE @jonheld was asking for help. I had to do a double take. It's rare to see one of the primary forum contributors requesting assistance on a problem.

I would have immediately suggested the overflow tube. I had similar issues but it wasn't as dramatic as yours: overflow would fill but then wouldn't fully refill rad after parked. I replaced my overflow tank and the hose and noticed that the original soft pliable hose was also very loose on the overflow nipple. I don't remember if the rad side was as loose. After replacing the tank and hose, I've never had any issues and the new hose was significantly more difficult to install.
 
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