I currently have my Formula parked until I replace its coolant reservoir. I have about five spare used factory Fiero coolant reservoir tanks here... and they all appear to leak.
Yes, I'm fully aware that the Fiero Store sells a rather pricey reproduction for $39.95... but with shipping to Canada being an additional total ripoff price of $49.82... they can keep their precious repro part.
What universal coolant reservoir tanks have people used? I've looked over the archives, and there's been very little posted about this here over the decades.
[This message has been edited by Patrick (edited 05-20-2023).]
The Fiero Store replacement sounds pretty reasonable to me. I value my time and fuel to go and scrounge one that does not fit properly. It just seems like a lot of unnecessary time and effort.
Originally posted by sanderson231: Can you tour a junk yard and see what would fit? Then buy a new one for that car.
That might be an option... "They" make OF Tanks of all kinds of shapes and find whatever and get from a yard is often cheap.
But... Those may not hold as much coolant. In Fiero, because 14+ quarts the coolant can "grows" more when hot then most front engines and w/ small tanks may not have space to handle Fiero heat cycle expansion and reserve capacity for minor leaks or weather cold and system sucks more coolant in to keep on air.
Yes, OF tanks has space above fill mark but this is so doesn't loose coolant like when engine is very hot like stuck in traffic, driving up/down hills, etc. + people forget the coolant gets Hotter when engine shut down adding to hot engine "problem" just said.
Is why Fiero tank is way bigger the most others but often is "over kill" for many owners.
Look at trucks and larger SUV too. Have more space in the engine bay and may have bigger OF tanks for similar reason as Fiero.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
In response to various points which have been brought up...
I started this thread in the hopes that I wouldn't have to re-invent the wheel Fiero coolant reservoir. I was hoping that someone, who has already gone through this, would stumble across this thread and post... "Just get a coolant reservoir from a 2012 Toyota Corolla"... or something along those lines. Maybe given enough time, that'll actually still happen. Either way, this thread should still end up being helpful to someone else down the road in the same situation.
The nearest wrecking yard that's now worthwhile going to from here is an hour away on the freeway. Sure, not an outrageous distance, but not a distance I wish to travel unless I know for sure that I'll be finding something I can use. I actually enjoy going to the wrecking yards and poking around... when it's warm and dry... not this time of year up here. Just out of curiosity I looked up what the "local" wrecking yard (Empire) charges for a coolant bottle, and it's about $11(US). Pretty reasonable!
A readily available new universal coolant reservoir tank is the Dorman 603-001.
I can currently buy one of these for $18(US), and that includes shipping. Its dimensions are 6"x4"x5" and its capacity is half a gallon. I don't know how that capacity compares to the stock Fiero reservoir. Anyone know off hand? If not, I'll measure the capacity later today.
[This message has been edited by Patrick (edited 03-10-2023).]
Originally posted by Patrick: A readily available new universal coolant reservoir tank is the Dorman 603-001.
I can currently buy one of these for $18(US), and that includes shipping. Its dimensions are 6"x4"x5" and its capacity is half a gallon. I don't know how that capacity compares to the stock Fiero reservoir. Anyone know off hand? If not, I'll measure the capacity later today.
Total Volume of OE tank is near 1 US gallon. At Full When Hot you add appox 1/2 gallon from empty.
Because of tank shape, empty to add mark isn't linear and likely < a quart for this "zone." If tank is @ add or below then radiator can suck on down side of heat cycling, more if has small coolant leak when system is hot. System can leak coolant out under pressure but suck air at same leak after shut down.
Been rain today and likely tomorrow so can't get my spare to measure exactly.
Any generic tanks and many OEM units for other vehicle need vertical flat spot to mount. If dorman etc are tipped to side more then a few degrees then working volume will be reduce some to a lot.
A readily available new universal coolant reservoir tank is the Dorman 603-001.
I can currently buy one of these for $18(US), and that includes shipping. Its dimensions are 6"x4"x5" and its capacity is half a gallon.
I want to say the stock tank was around 3.5 quarts. But it's been awhile. My memory might be off.
The aluminum tank I used was about 1.5 quart. I filled so it was almost full when the engine was hot. And it was almost empty when the engine was cold. So 2 quarts should be enough. But you'll likely end up using almost all the tank's capacity, like I did.
I figured I'd better get back to this thread. Thanks for your insights/posts everyone.
When I removed the reservoir tank from my Formula, I filled it with water and propped it up in a large bucket to see where it was leaking from. Wouldn't you know it, not a drop leaked out.
When it was in the car, it would eventually empty out completely within a week or so (with coolant on the ground under the front of the car). I didn't know if being bolted in place was contributing to a crack being opened up (although I did not have the two mounting nuts very tight), or maybe it was hot water from the rad that was contributing to a crack being wide enough to leak. So I filled the tank with boiling water... and still not a drop was leaked!
I'm beginning to suspect that this reservoir tank is not leaking at all. I'm now thinking that the leak is somewhere else in the cooling system in the front of the car, and the coolant is being sucked from the reservoir by the resulting vacuum in the cooling system. Is that possible... with a car that's just sitting, not running for a week or so?
I usually have my Formula parked on the street, so it was easy to see the wet spots under the car on the asphalt. However, before I removed the reservoir, I parked the car in my yard on the dirt/grass/gravel driveway, so it's not all that easy now to see if it's been leaking coolant. It's also been raining, which contributes to me not wanting to get under the car. But sunshine is forecast this week, so I'm going to have to get under there and see what the heck is going on.
Oh, by the way... I measured the capacity of the reservoir tonight. It's about 4.5 quarts!
"Leaking Tank" is often not the Tank but Radiator sucking it dry during heat cycling because have small coolant leak somewhere else.
Coolant can leak out anywhere when hot and iffy hose joints etc often doesn't let air back in except thru the OF tank path sucking coolant then air when tank is dry after shut down.
Do not "crush" the tank line and Rad fitting by using any strong clamps. Old tank hose gets hard and fail to seal at either end and people then use worm clamps etc that crush the rad tube over time if not immediate. Is why GM only use "weak" plastic clamp there.
If Rad has ever been replace, look careful at OV Tank outlet. Tube section Often have mold flash etc causing hose seal fail.
I have a very tiny leak doing that for months and can't find it even after replacing many hoses or cleaning joints. I just check the tank every month.
Is 4.5q the Total Volume? did you check empty to add and empty to full marks?
[This message has been edited by theogre (edited 03-15-2023).]
I bought one of the "universal" tanks from Advance Auto. But I deleted my front tank and moved the overflow to the back. Radiator has a 20# cap, so it should never "vent". I have a fill adapter on the rear with a 15# cap, with a hose to the overflow bottle.
I'm now thinking that the leak is somewhere else in the cooling system in the front of the car, and the coolant is being sucked from the reservoir by the resulting vacuum in the cooling system.
quote
Originally posted by theogre:
"Leaking Tank" is often not the Tank but Radiator sucking it dry during heat cycling because have small coolant leak somewhere else.
A few days ago I swapped in the coolant reservoir tank from my '84 (to try and eliminate one variable), topped up the coolant, and then let the engine run for 20 minutes. I couldn't see any evidence of a leak anywhere. I left the car alone for a few days, as it was raining anyway. Today was nice (Spring has sprung!), so I had a look at the car again this afternoon. I noticed this one wet spot on the front of the radiator.
I thought I had possibly found the leak... so I started the engine and let it run for ten minutes. Not only did it not leak any further from this area, but the wet spot completely disappeared as the radiator got warm. After I turned off the engine, I checked that area of the radiator two hours later (the radiator was cool), and there was absolutely no evidence of any moisture. I'm now beginning to think the wet area in the photo was the result of water working its way there during the rain we had the last few days. I'll check it again tomorrow!
[This message has been edited by Patrick (edited 03-21-2023).]
After sitting for 24 hours, I saw no sign of any coolant leak. Doesn't mean that there still isn't one, just that I can't see it. I've now parked my Formula back on the street, so if it is leaking coolant, I should be able to see some evidence on the blacktop.
I had the thermostat removed for a few days during the refilling/testing stage... and when I went to reinstall it, this is what I saw. Anyone care to guess what's going on here? I do know what happened... I'm just testing your knowledge.
backward order... "Dyno" and most Syn Oil/Grease on o-ring make it swell. Same problem w/ rubber brake parts. Often gets oil/grease on the rubber to lube to install X part then "Dry out" when out/off and rubber swell then. Rad and T-stat caps get same problem. Use Silicone oil or grease or Permatex brake grease. oil/grease w/ same on T-stat cap "Rivet" on top of cap too. Stops "rust" that stops swiveling the seal and make the cap very hard to remove later. I once had a T-stat cap looked ok first when pulled then coolant start to dry then rubber warped. I installed it but was in a rush and wiped the tube edge w/ engine oil to stop tube rusting... Good thing I keep extra caps in inventory.
Thanks for data. Can't find my spare to get that info.
Careful w/ Rad and other coolant leaks... Small leaks can "Self seal" intermittently until corrosion eats more metal, hose(s) finally fail, etc and suddenly have way bigger leak often on highway in heavy traffic and other bad times.
"Dyno" and most Syn Oil/Grease on o-ring make it swell.
Bingo!
I've been putting grease on the Fiero's thermostat O-ring for decades (for easier installation into the housing), and never had a problem. Even when I pulled this thermostat out last week, the O-ring appeared to be fine. It wasn't until I left the thermostat out of the engine for several days that the O-ring had an opportunity to swell up. Lesson learned!
I've now parked my Formula back on the street, so if it is leaking coolant, I should be able to see some evidence on the blacktop.
Well, my strategy worked. After parking my Formula on the street three days ago, and not moving it, there were coolant drips under the middle of the car when I had a look today. Using a flashlight, I can now clearly see a drop of coolant on the screw head for a clamp on one of the heater core coolant lines.
This is an image found online of the underside of an '86 (should be similar enough to my '88), and I've indicated where I can see the drop of coolant. It remains to be seen if the leak is actually right there, or whether the coolant is running there from a leak located elsewhere.
[This message has been edited by Patrick (edited 05-05-2023).]
No surprise to me... been there just last year. ⚠️ Warning: Heater pipes are Aluminum tube. Very likely other bracket &/or metal under gas tank have issues and damage to plastic on the tube at minimum.
cut at the leak, install 3/4" rubber hose. Non stock item @ most local store but most can order same or next day w/o shipping charge. Likely the bracket won't fit w/o mod or replace w/ other metal.
Only need 2 clamps on hose. Can't "blow out/off" because other things stops the tube section moving.
I finally got around to dealing with this coolant leak. I'll blame my delay on the wet weather we've been having here for weeks.
The biggest hassle was getting the car up high enough, and safe enough, for me to be working under it. I had a bit of trouble determining where the leak actually was. It was always a very slow leak, so I knew I'd have to get the coolant good and hot, and under pressure, to find it. It seemed to me that the foam covering over the heater core inlet tube under the car was damp. I figured I'd start from the front, and open up the foam with an incision down the length of the pipe... but starting with just the first six inches from where it connects to the heater core inlet rubber hose. There's a plastic bracket that holds both tubes (inlet and outlet) to the underside of the car. This is what the bracket looks like (although this one is from a different area).
CLICK FOR FULL SIZE
The bracket was clamped onto the two tubes, and was immediately adjacent to where the rubber hoses connected to the tubes. It seemed a little damp around the inlet tube when I took the bracket off... and sure enough, this is what I eventually saw after waiting about ten minutes.
I tried just tightening the clamp, but it still leaked very slowly. So I moved the clamp closer to the edge of the hose, and put a second clamp on for good measure right next to it. I let the engine run for several minutes so that the rubber got a bit softer, and tightened all the clamps a little bit more. I believe it's okay now. I added a green arrow to the shot from my previous post pointing to the area where I was working.
If the leak is now resolved, I think I got off pretty easy. I feel very fortunate.
If you didn't remove the hose(s) then will leak again there and likely soon.
Again, heater pipes are Aluminum. Can rot at support brackets and anywhere touches other metal as cover in above link. Can also rot at hose connections like T-stat tube too. More so if has weak/no coolant.
At minimum, need to remove that hose to clean the joint. Get proper hose pinch tools and pinch hoses at both ends of pipe. You don't need to empty the system and likely loose ~ 1 quart of coolant if pipe fully drains. Example now in leak link above.
I would do all hose joints w/ clamps on heater loop after 1 was leaking. At least the ones under the car.
Get proper hose pinch tools and pinch hoses at both ends of pipe.
I've never felt comfortable "pinching" older rubber coolant hoses or fuel lines. I'll only pinch a brand new hose.
quote
Originally posted by theogre:
If you didn't remove the hose(s) then will leak again there and likely soon.
I feel pretty confident that with two clamps (one flipped around from the other's orientation) on the connection, both in slightly different locations than where the original single clamp was located, that the seal will be fine. The hose itself is not rotten. I've done this many times on previous cars over the decades and not had a problem. However... IF a leak develops... I will post about it here!
Glad you found it. I can relate to this type of ordeal for sure and I am sure most of us can. Seems coolant like to travel a bit before actually dropping making it a mystery sometimes to find where it came from. lol
Seems coolant like to travel a bit before actually dropping making it a mystery sometimes to find where it came from. lol
Very true! What made this even more challenging, was that the coolant appeared to be travelling inside the foam rubber sheath on the "hot" heater core tube. The coolant was entering the forward end of the sheath where it angles up (green arrow in previous post) and running down towards where the clamp is (red arrow) and escaping the sheath at that location (due to an opening in the foam sheath where the clamp attaches).
Originally posted by Patrick: I've never felt comfortable "pinching" older rubber coolant hoses or fuel lines. I'll only pinch a brand new hose.
Old hoses never had problems w/ pinching if you follow the "rules." IE use something w/o shape edges and only pinch to stop flow. Also have to be far enough from joints to so rubber just bends not stretch on edges whatever inside.
For the rear, find an area to pinch maybe harder because short hoses and w/o pipes in it.
Above tool has no sharps but also pinching parts "floats" some to stay parallel w/ hose in them so doesn't pinch 1 area too much. If this tool "cause" old hose to fail is very likely already "dead" and fail very soon. Example: "Top" Coolant hose on Engine end goes very weak because of engine heat and "bad" coolant. If that hose is pinch, just pushes over the edge to fail sooner but was going to fail regardless.
But even KD and GearWrench shows pic's like this and way to close to the end...
Above tool has no sharps but also pinching parts "floats" some to stay parallel w/ hose in them so doesn't pinch 1 area too much. If this tool "cause" old hose to fail is very likely already "dead" and fail very soon... just pushes over the edge to fail sooner but was going to fail regardless.
I wouldn't disagree that I perhaps keep hoses on my cars well past their prime... but I've never had one catastrophically fail while in use... possibly because I never "pinch" them during any kind of maintenance. I just feel it's (potentially) too damaging to a hose to completely flatten it, even with the "proper" pinching tool. It puts a helluva lot of stress on the two edges that are bent over 180° and compressed. This is not how a hose is meant to be manipulated in normal use.
[This message has been edited by Patrick (edited 05-05-2023).]
Patrick, glad you were able to find the leak. Back to the coolant tank….. I wanted to make a few comments: 1) From my experience, 99% of the leaks are from the bottom outlet nipple and of these it’s not the nipple that is leaking. It’s the hose clamp! (it ain’t tight enough) And yes, the design of the nipple is poor and kind of fragile. 😕 This is why they provide that brass ferrule, so you don’t crush an already fragile tube. Anyways, this is why I ALWAYS use two hose clamps on this nipple. Otherwise, your chances of a leak here are much greater.
2) Never tried it myself but there are a few videos on YouTube showing how you can repair coolant overflow tanks with epoxy resin.
3) Here’s a great tip on how to clean out the “muck” inside a coolant tank: Buy a small box of BB’s, plug bottom of tank nipple, create a mixture of cleaning liquid, soap, hand cleaner, etc., pour into coolant tank with the bb’s, put on top cap, “shake tank until your arms fall off” and presto you got yourself a clean tank. 😀 Kit
[This message has been edited by Kitskaboodle (edited 05-08-2023).]
Originally posted by Kitskaboodle: Back to the coolant tank….. I wanted to make a few comments: 1) From my experience, 99% of the leaks are from the bottom outlet nipple and of these it’s not the nipple that is leaking. It’s the hose clamp! (it ain’t tight enough) And yes, the design of the nipple is poor and kind of fragile. 😕 This is why they provide that brass ferrule, so you don’t crush an already fragile tube. Anyways, this is why I ALWAYS use two hose clamps on this nipple. Otherwise, your chances of a leak here are much greater.
2) Never tried it myself but there are a few videos on YouTube showing how you can repair coolant overflow tanks with epoxy resin.
1. Hose between OF Tank and Rad or whatever never needs a tight clamp to seal because no pressure to deal with. That's why GM and others very often have no clamps or have "Weak" clamps like plastic pinch-on type on this hose like 90+% of Vacuum hoses.
Main problem the hose goes very soft, hard or other problems and won't seal right even w/ metal clamps. Bad/no coolant attacks from inside and oil etc attacks it from outside.
Is also similar problems w/ chain saws etc plastic fuel lines that need to be replace because line shrinks etc causing tank leaks and more problems.
Another issue is Rad Out Tube for OF hose is often made iffy and defects like mold flash on plastic rad tanks not removed or filled and cause a leak.
2. Plastic Weld Epoxy and other "Glues" available to the public won't work on most or all plastic tanks. Doesn't work on many other plastic items for long either. More so when is made of Polypropylene and Polyethylene that close = to Teflon that very few things stick to it. (Even Krylon Fusion paints have issues and its made for painting plastic.)
You can Weld PP PE and some others but very thin line between melting and burning. Burned plastic many hold for a while and "blow apart" w/o warning.
But If been expose to UV and other things causing plastic to break down, Welding can fail too. Weld may actually hold but plastic just fails anywhere else under load in short term.
I'm always surprise Fiero OF Tank w/ brass fitting work so long because again most glues "hate" PP and PE. Even if "Welded" the metal and plastic have different thermal specs and heat cycle stress can make them fail over time.
Side Note: First version of the "Beer Ball" was PE before switch to PETE.
But If been expose to UV and other things causing plastic to break down...
That is exactly what the genesis of this thread was... the plastic on one corner of my original coolant reservoir broke down due to UV rays coming through one of my hood vents. Here's the hood...
And here's what ten years worth of UV rays have done to the corner of the reservoir that was exposed...
I fabricated an aluminum sheet metal cover for my replacement reservoir today, so as to prevent it from suffering the same fate. I'll post a photo when installed.
[This message has been edited by Patrick (edited 05-20-2023).]
But the Bolt Hole breaks just for load on small upper section. GM used a captive washer nut but doesn't help much.
Better is sandwich the "ear" w/ light sheet metal that folded under the ear so a lot more plastic is supported.
Bottom bolt hole breaks too often because upper already broke and GM and others over torqued the hardware.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
Ugly... But the Bolt Hole breaks just for load on small upper section.
Just for clarification... I wasn't suggesting that UV rays had anything to do with the broken plastic mounting tab. It was already broken when I got the Formula, which of course at the time had the factory hood with no vents.
I fabricated my reservoir cover using my '84 as a template... and then I realized that it wasn't going to fit the Formula (without further modification) because the Formula has a rad fan shroud (was originally an A/C car) whereas the '84 has a regular rad fan mount. Had to change things up a bit as I designed the reservoir cover to attach to the top right rad fan mounting bolt. Not a big deal, but I'm as slow as cold molasses.
Okay, reservoir shield installed. The orange colored arrow is pointing to the area where the previous reservoir was destroyed by UV rays coming through one of my hood vents. The red arrows are pointing to where the shield is attached.
Not bad re-use of a 10" length of old aluminum gutter.
I'm now thinking that the leak is somewhere else in the cooling system in the front of the car, and the coolant is being sucked from the reservoir by the resulting vacuum in the cooling system. Is that possible... with a car that's just sitting, not running for a week or so?
I'll check it again tomorrow!
