Radiator Flushing - Kleen-Flo product

73SC · A Poncho Legend!

Radiator Flushing - Kleen-Flo product

long stroke · Canadian Poncho Superstar!

Snake oil magical elixer.

Leo2+2 · Guru

Ray, I've used it a couple of years ago. Did the job at the time.

73SC · A Poncho Legend!

My Jobber said he sells cases to the local shops, maybe a nice way to turn some added revenue for them. At less that 10 bucks I figured I'll give it a shot, new coolant and distilled water should be good to go for the rest of the summer.

seventy2plus2 · Canadian Poncho Superstar!

I've got a couple bottles of the Prestone equivalent. I ran some through my low mileage 2+2 350 a couple years ago. The coolant was quite brown before I started, and while it improved I didn't get the desired results. I didn't really have any instructions, I later learned I had to peel off the back label to get instructions. I'll have to give it another go here this summer, and maybe run it in the car for a couple days to really loosen things up then flush the heck out of it.
Note: That's the problem with not driving cars often enough, it should have been flushed years before.

73SC · A Poncho Legend!

The interesting thing is that the FSM for my Corvette describes the flushing process in good detail and suggests every 5 years or 100,000 miles. It doesn't say to leave the flushing agent in the radiator for a couple of days and even warns about driving the car around with the stuff in it. Its basically a one hour procedure. I'm inclined to be like you though Clint and follow the instructions to the letter.

Anyway I sent my guy to the dealer today to get the coolant and distilled water, he came back with Dex Cool and I was disappointed to see that. I told him the Corvette does not take that orange stuff and he told me that the parts guy looked up the 93 LT 1 Corvette and gave him the coolant. I called them back and they had to admit their error so my morning plan is off schedule now while we head back and get the right coolant.

I'm going down this path because I had two hoses burst on me a week apart, The car never overheated. I'm not really sure what it is going to accomplish because on a recent trip to the cottage, 2 hours and 15 minutes the highest temp I saw was 107 in bumper to bumper on HWY 400 and at cruising speed it settled down to 92, once the sun went down and I was cruising the county roads it settled in at 89. I figure partly that the coolant has been topped up twice lately so I should probably just put in fresh and figured the flush would be a good idea too.

73SC · A Poncho Legend!

Reporting in after flush.

Drained radiator of coolant and refilled with water and the Kleen Flo product. It has a very distinctive odor to it and obviously has solvents and cleaners in it. Per instructions ran engine for 10 minutes which really turned out to be 12. I did put on heater as per FSM so that heater core could benefit as well. After this opened the petcock and put the garden hose in the radiator tank and started flushing it out until it ran clear. This took about 40 minutes. Let it drain and then added Coolant and distilled water. The picture below shows a batch of drained coolant and kleen flo, it obviously gets limestone deposits out and you could see some rusty bits and brownish water running out as the fluid became less milky green. Test drove the car, went downtown via Bayview extension a semi expressway road that feeds the highway through Toronto and Rosedale Valley Road a 40 minute round trip. The car ran mostly between 89 and 92 but did get up to 104 at traffic lights which isn't hot enough for fans to come on. System seemed to work A Okay. I'm satisfied that radiator was cleaned but didn't see any evidence that it was in bad shape. One of the benefits of having a car from stateside and not winter driven is there is no rust and the petcock was by far the easiest one I have ever encountered on a car and this thing is 27 years old.

-- Edited by 73SC on Sunday 9th of August 2020 12:17:52 AM

73SC · A Poncho Legend!

I've had a week to drive around now commuting to work in a combination of city streets and expressways. The weather has been very hot and humid hovering from 29 to 32 here in Toronto.

In morning light traffic on the Don Valley Parkway at speeds of up to 120 kph the car runs 89 and 90 all the way downtown, a 10 to 12 minute highway run, switch to Queen street which intersects the famous Yonge and Bay and University Avenue and it will get up to 92 or 94. This is a full 3 degrees lower than before the flush. On way home there is a long climb out of the valley up Pottery Road and it reaches 97 or 98 again at least 3 degrees lower than before the flush. So I am satisfied this product does what it says it will do, a more efficient cooling system. I plan to take it on a long two hour highway run next week so I can report back then as well.

4SPEED427 · A Poncho Legend!

long stroke wrote:
Snake oil magical elixer.

I totally disagree. I've seen what rad flush products can do and Ray's observation is on the tame side. I've seen them do more dramatic work than that on a cooling system.

One down side to using them is the leaky heater cores that sometimes result from using rad flush. All the junk in the core has clogged the leak until the flush washes it clean. GM has a good rad flush as well, (or at least used to, it may be discontinued) but boy is it a powerful smell. I wouldn't rinse it all out in an small enclosed area.

73SC · A Poncho Legend!

You make good points Carl, I did make sure to run the heater in order to get the flush in the heater core as well and the smell is very powerful, I heard my neighbor yelling at her husband wondering what that smell was and my car was at least the length of their lot, about 130 feet in city lot size, away. I was pleased to see that my rad was in good shape. I got two bottles so I still have one left. I though that I might need to double treat my Corvette but as Carl points out my results were tame but overall good so I didn't bother.