Nit-picking as I plan my radiator-flush and hose replacements

[BonzaiDuck]

I once just let the mechanic (my now-retired "Master Mechanic") advise me when I needed to replace radiator hoses, and my last hose replacement occurred at a crisis moment when my water-pump froze and my radiator was damaged. That was twelve years ago, but the car has been driven only 29,000 miles since then. Available wisdom says to replace the hoses once every 5 years or 60,000 miles, and I believe the time-span is not the critical factor: I think there is an assumption there that people will drive about 12,000 miles per year. We put about 3,000 miles per year on each of our vehicles.

The cooling system was flushed about that time, also. Additional repairs a couple years later would've mandated replacement of anti-freeze. But in all, we're at most talking about antifreeze and hoses that are at MOST 29,000 miles old, but over a span of 12 years.

I have ordered a new set of DAYCO hoses through RockAuto -- to arrive on Wednesday three days from now. I've stockpiled three gallons of 50-50 antifreeze and six gallons of distilled water (@ $0.95 / gallon). I have a new 170F Thermostat ready, a new $2 radiator-drain petcock, and a set of new hose-band-clamps.

The longest of the two major radiator hoses has its bottom radiator connection in a very tight place. It will be a lot of extra work to remove that connection, and a bit troublesome to reconnect a stiff new hose. I've researched some options, like removal of the lower radiator fan shroud -- a spring clip on either side and a lock at the bottom. I should be able to slide this lower shroud around enough to make the hose connection more accessible (and visible!)

In 2017, the Master Mechanic checked the anti-freeze and his notes say that it was "OK". But because of other repairs this year, the cooling system needed topping up, so a different brand of ethylene glycol antifreeze was added to the original stuff provided through the Master Mechanic. This would possibly compromise any anti-corrosion additives in the original antifreeze. And when I warm up the car with the radiator cap removed, I can see powdery residue occasionally churning in the fluid.

I think it's time for a flush. Wisdom about flushing the radiator says that it is convenient to replace the hoses (obviously). There is a suggestion that the old hoses might hold some leftover contamination, but this seems to be a cautionary afterthought of less consequence.

It's been a rough summer renewing our two vehicles. I've "suspended" the repair-shop replacement for the retired Master Mechanic. I cannot trust those people to do anything to my vehicle without screwing up something else, so I'm taking over oil changes, radiator flushes, and other maintenance functions until I can find a repair outfit that doesn't promote unnecessary labor-intensive repairs that can wait, or who lie to the customer about damages they did under warranty so the customer will pay more. I cannot abide by any of that S***.

There are no cracks or deterioration on the hose ends for my radiator hoses. There is no swelling around the flange lips of the hose fittings. There are no cracks or bulges in the hoses. There are no "soft spots".

What would you do?

1) Replace ALL of the hoses, and go through the misery of dealing with the bottom connection of the long radiator hose.
2) Replace all the hoses EXCEPT for the long radiator hose, and save it for next year. [I won't have to "flush" the radiator next year, but only need to replace the radiator fluid with the same brand and formulation.]
3) Defer ALL hose replacements for one year, but flush the radiator NOW.

Also, I'm a bit skittish about radiator additives, and I recoil at the idea of putting a "T" fitting into the hose line to "back-flush" a cooling system. I once blew a head gasket that way, ending in an engine overhaul. Just the idea of using Prestone Radiator Flush and Cleaner causes me some concern.

There are no pressure leaks in the system. There is no indication of anything suggesting a head gasket leak. The car "gits up and goes" -- never overheats. If I use the Prestone, I intend to do the "10-minute flush" -- running the car in place, quickly removing the Prestone/distilled-water mix after cool-down, replacing with more distilled water and then putting in the 50-50 antifreeze.

 

[someone16]

I'd just leave it if it looks fine. What would really ruin them is if you have an oil leak and it ends up getting onto the hoses, so check that first.

Also you typed on all that but didn't say what car it was? I'm sure somebody here will have better advice knowing what car it is.

 

[BonzaiDuck]

Maybe I just overestimated the peanut gallery. I've been posting a LOT during the last four to six months at this "Garage" forum. There is only one, true vehicle other than my brother's 95 Nissan Pickup SE -- which I maintain as a family duty.

It is the 1995 Isuzu Trooper LS.

There are two groups of people, one at either end of the spectrum regarding this orphaned SUV. There are enthusiasts and cultists on the one hand, some of them posting boastful summaries on classic-car web-sites. On the other, there is a group from which you hear "Isuzu? WHAT is an ISUZU?" or from my mechanic cousin "You need to get some 'merican Iron!" -- and from the Mechanic-From-Hell whose cluster-fuck of serial damage to my Trooper makes me imagine him mumbling over my engine compartment "Troopers?! We don' need no stinkeen Troopers! Whadda we need stinkeen Troopers for?!"

187,000+ miles
Smog-test in 2018 was better than it was when I bought it in 2002
New suspension, brakes, PS hoses, etc.
60,000 miles on the tranny
30,000 miles on alternator, water-pump and radiator (and the hoses of subject topic)
Tires with less than a year's wear, if you figure people drive 12,000 miles/annum
12-CD changer, frosty A/C, automated exterior side-mirrors
Chrome rims
Grille-guard
Blue Metallic Pearl and Iron Metallic Gray paint that looks new

Hey! You asked!

There were never any oil leaks to contaminate my hoses -- to speak of. I'll say what -- since I'd had a PS steering fluid (Dexron) leak in the hose near the difficult "long" radiator hose, I'll get a lamp on it and check. But that was just a drool, and was being blown back toward the belts and engine -- away from the radiator hoses.

 

[BonzaiDuck]

Heh-heh . . . . That long, difficult hose from the bottom of the radiator is dry as a bone -- no bulges, cracks -- nothing.

I feel more comfortable with the idea of skipping the hoses this time, and merely giving the cooling system the complete flush. I won't even replace the thermostat until I'm ready to replace those hoses, and I'll simply put the new ones from RockAuto back in my parts locker until maybe next year.

. . . Maybe I'll just spend $3 on a roll of self-fusing rubber hose bandage and throw it in the glove box, just to be prepared . . .

Maybe I'll have the A/C refrigerant charge checked by another prospective shop in January or February.

What a ride! What a ride! Who has stinkeen Troopers? Nobody has stinkeen Troopers! Whadda they need stinkeen Troopers for?! I could give up my secret here, about getting a California vanity plate: "SPRDUPR" or "SUPRDPR"

 

[someone16]

My bad, didn't seem to connect the dots on all the other threads you had! Well it does sound like you want to stay on top on of everything that can cause you trouble.

People have said that the upper hose usually wears out faster due to constant heating and cooling vs the lower hose. So if you really want to stay ahead of the game you can replace the top hose + change the coolant and leave the bottom hose.

At this point it's a balancing act between spending money doing work and leaving it until it's necessary. I mean technically anything that is plastic/rubber in the car would degrade after so many years and you can make an argument to replace it.

 

[BonzaiDuck]

My bad, didn't seem to connect the dots on all the other threads you had! Well it does sound like you want to stay on top on of everything that can cause you trouble.

People have said that the upper hose usually wears out faster due to constant heating and cooling vs the lower hose. So if you really want to stay ahead of the game you can replace the top hose + change the coolant and leave the bottom hose.

At this point it's a balancing act between spending money doing work and leaving it until it's necessary. I mean technically anything that is plastic/rubber in the car would degrade after so many years and you can make an argument to replace it.

Sure! But how soon? 12 years on those hoses, but only 29,000 miles or so. No bulges. No cracks. No soft spots. I think I'll probably go ahead and replace the upper hoses and defer the big one. Or -- maybe once I "get into it" -- I'll just do them all.

See, we have two vehicles. There's my 94-year-old Moms and my 62-year-old disabled brother just out of surgery on his leg -- so he can keep it. Moms has like 10 doctor's appointments per year, and there are those of my brother -- obviously. He can't drive the 5-speed manual pickup -- which is his. He's got to drive the Isuzu when he's in better shape than he is now. And the Trooper is the only vehicle which allows comfortable transport for three people. As a "backyard mechanic" -- my preference is to take my goddam time. I don't need the constraints of getting something done according to a shop rate manual, and if you don't do things repetitively, doing them the first or second time causes more worry, time -- planning. But in this situation, I can't leave the Trooper disassembled for very long.

That's why it was so important this year to try and establish a relationship with a new repair shop that had promise for the long term. After the troubles with the Mechanic from Hell, the search continues, and I've got to manage on my own until I find someone trustworthy to pay for the work.

 

[BonzaiDuck]

Well . . . I've finally, after 15 years of BonzaiDuck anonymity, revealed myself with an avatar, as I have consistently presented myself to the world since buying the Trooper as the reincarnation of Ed Abbey -- environmentalist, career seasonal NPS Ranger, author and Southwestern US literary icon. So -- sure -- the Trooper -- part of the overall accoutrement. It's OK to impersonate an interesting person in your local historical tradition. Become what you wanna be. Vanity, vanity. My theory is that the Machine Manitou of the Isuzu has invaded my soul to raise this masquerade 18 years ago. Abbey wanted to be reincarnated as a Turkey Vulture, so maybe he decided to take a leap when we drove by a dead Mesquite back in '02 in his burial place of Cabeza Prieta, where about 20 of the birds had socially congregated. Anyway, no exorcism needed; my possession is benign and not malignant like Star Trek's Borg.

Here are my latest discoveries drawn from white papers on sites by companies like "Gates" -- who manufacture hoses.

There are three types or formulations of ethylene glycol (that's the compound -- right?) antifreeze products. IAT, OATS(?) and HOAT(?). IAT is the oldest, and uses silicates in its corrosion-protection function. (Please correct me if I'm wrong about this or that detail). The others use an organic chemical anti-corrosion formula. With absolute certainty, when IAT mixes with one of the other two, there is a chemical reaction which generates a light powdery substance. This light powdery substance eventually clings to the seals of the water pump, and eventually cause the seals to fail. And when the seals fail, the antifreeze invades the bearings of the water pump, so eventually, the pump fails and seizes up. When it seizes up, it can cause the timing belt to break, and for failing to keep water flowing, it might damage the radiator, cause overheating and a head gasket leak, and even lead to bent valves.

So whether I topped up my radiator with a formulation that conflicts with Master Mechanic Dick's choice for his customers, or one that didn't, the powdery substance I've occasionally seen recently when material flows into the top of the radiator is either ordinary corrosion byproduct from the engine cooling jacket, or it is the result of mixing two different types of antifreeze.

If the latter, corrosion on the water pump can begin within 5,000 miles of driving. If the former, there is junk in the antifreeze that wasn't there when most of it was put in the cooling jacket at the last flush or maybe a couple years later.

Either way, it is imperative to flush the cooling system now.

As for the hoses, the hose showing the most wear is the upper hose mentioned by someone16 -- the easiest hose to access and easiest to replace. Even the wear is questionable: it could be dirt around the edge of the hose-clamp band, or it could be the woven fibers beginning to show through the outer rubber. The spots are so small that I believe further examination will show that it's dirt. But this would be an easy opportunity to replace that hose.

The lower or "long" hose looks brand-new in comparison to the upper one. All the other hoses have a thicker wall, are narrower, and look next-to-new sturdy.

The priority is to flush that sucker and replace the antifreeze. I can diddle with the hoses as I please, then look for signs of wear over the next year or beyond. I'll probably replace the upper hose now. Why not? Can I twist a screwdriver? Do bears shit in the woods?

 

[BonzaiDuck]

OVERLY ENTHUSIASTIC UPDATE

Some cars have bleed valves or drain valves on the engine, but the prevailing option is limited to the petcock drain plug in the radiator. If you measure the amount of fluid you can drain in a single pass, you will see that you still have 55% of the original fluid left in the cooling system.

Suppose you drain a gallon, and suppose your capacity spec is 2.32 gallons? If you perform the operation 8 times, successively adding 8 gallons of distilled water to the radiator fill-neck, you will still have about 1% of the original 50-50 anti-freeze mix in the system, plus some tiny amount of the radiator-flush product you added the first time.

The drained fluid will still look just a bit like Lime Kool-Aid. The next time you drain off 1 gallon and just fill with 50-50 mix, your EC or engine coolant will still have 6/1000 of the original mix-- which, after all, was already 50% distilled water. 0.3% is not a lot of impurities in your resulting radiator contents, since most of it was ethylene glycol!

After that, you can probably drain a gallon a year, replace a hose here or there and eventually the thermostat.

 

[WackyDan]

My last truck was a Dodge Dakota which I replaced after 13 years (bought new) of ownership. Never had to replace a single hose after 120k miles.
Our last car was a 2005 Chevy Malibu we just replaced after 13 years and 113k miles. Only hose I had to replace was at 12 years and it was a small 5/8 inch connector hose that sprung a leak at the clamp.
My F-150 is now 7 1/2 years old at 42k miles and is just fine.

If this was a 1970's or 1980's vehicle the hoses would already have been replaced at similar mileage. Materials have gotten better apparently.

As for coolant changes - My F-150 only allows me to drain about 1 1/4 gallons out of it. So I only get about a 1/4 to 1/3 the coolant out. I just do that once a year during an oil change under the assumption that I'm introducing enough fresh coolant that it is more than maintaining the anti corrosion and lubrication properties the truck needs. So far no issues.

 

[deadlyapp]

If you were really, truly, really worried about some tiny extra bit of sediment in your system that wouldn't be caught in the bottom of your radiator, you could easily jury rig up a system with a cheap pump and in-line filter and a couple of rubbermaid tubs. Shit you could probably do it without a pump and just gravity feed it from a higher elevation into the motor with the thermostat removed while running the motor and letting it drain out the bottom of the radiator.

 

[BonzaiDuck]

Well, the last cycle with distilled water to replace a gallon in the cooling system produced something like really weak lime Kool-Aid in the drain pan. If I replace a gallon of the 50-50 coolant every six months or each year, I doubt I'll need to perform this kind of thorough flush for a long while.

The new Universal coolant is yellow instead of green. My main concern going forward is to avoid mixing different brands of anti-freeze by "topping up" or any similar replacement operation.

As for "water-pump lubricant", these products really only rejuvenate the WP seals and keep them from leaking. I've chosen Red-Line Water Wetter. Every time I replace a gallon of anti-freeze 50-50, I'll add a half bottle of this stuff. Some say don't bother; I say it won't hurt.

As for the hoses, one has to get a sense of what hose deterioration is. I might have left the hoses alone, but I replaced the top hose so I could look at it. I won't regret the $30-worth of hoses that I ordered; I'll just keep them in storage until needed.

I just had my A/C system recharged for about $125. It was worth it. The repair-shop reported that the system was over-charged. It had been that way for at least a few years, which seems strange, because all A/C systems leak slowly. The excess refrigerant was the cause of sub-optimal cooling. They replaced the refrigerant and charged it to spec pressure. It's very frosty now.

I may use that repair shop in the future, but only if the A/C compressor, power-steering pump or steering-gear-box give out -- the only three things besides the engine that could fail. I'm going to assume responsibility for my oil-changes, cooling system and minor repairs. It was a bad summer, what with the Shop of Horrors and Mechanic from Hell.

These are the battles one must fight to keep an old car tip-top and on the road.

 

[deadlyapp]

Well, the last cycle with distilled water to replace a gallon in the cooling system produced something like really weak lime Kool-Aid in the drain pan. If I replace a gallon of the 50-50 coolant every six months or each year, I doubt I'll need to perform this kind of thorough flush for a long while.

The new Universal coolant is yellow instead of green. My main concern going forward is to avoid mixing different brands of anti-freeze by "topping up" or any similar replacement operation.

As for "water-pump lubricant", these products really only rejuvenate the WP seals and keep them from leaking. I've chosen Red-Line Water Wetter. Every time I replace a gallon of anti-freeze 50-50, I'll add a half bottle of this stuff. Some say don't bother; I say it won't hurt.

As for the hoses, one has to get a sense of what hose deterioration is. I might have left the hoses alone, but I replaced the top hose so I could look at it. I won't regret the $30-worth of hoses that I ordered; I'll just keep them in storage until needed.

I just had my A/C system recharged for about $125. It was worth it. The repair-shop reported that the system was over-charged. It had been that way for at least a few years, which seems strange, because all A/C systems leak slowly. The excess refrigerant was the cause of sub-optimal cooling. They replaced the refrigerant and charged it to spec pressure. It's very frosty now.

I may use that repair shop in the future, but only if the A/C compressor, power-steering pump or steering-gear-box give out -- the only three things besides the engine that could fail. I'm going to assume responsibility for my oil-changes, cooling system and minor repairs. It was a bad summer, what with the Shop of Horrors and Mechanic from Hell.

These are the battles one must fight to keep an old car tip-top and on the road.

Water wetter in combination with Antifreeze/normal coolant is pretty much a waste of money. Water wetter however is fantastic in an environment where you never have to worry about freezing temperatures and can forego antifreeze/glycol mixes completely.

 

[BonzaiDuck]

Water wetter in combination with Antifreeze/normal coolant is pretty much a waste of money. Water wetter however is fantastic in an environment where you never have to worry about freezing temperatures and can forego antifreeze/glycol mixes completely.

But not much of a waste, at something like $7 or $8. Even so, and if it does what it's supposed to do, you'd have no need for it if you simply replaced half the coolant annually -- assuming you used the same coolant.

I'm just discovering how I might have saved myself a pile of change in past repairs, if I had done regular cooling system flushes. Anti-freeze is cheap; the work is a minor pain in the ass. But I think paying more attention to it is a wise thing . . .