Well, after installing my intake gasket for the 3rd time, this month and finally using RTV on the end seals, I've noticed when I drain the antifreeze out and it sits in the catch basin I'm using, the bottom 1/8" looks rusty/dirty/oily.

The radiator cores do have Calcium(I think) deposits on them. (i believe a two care radiator). I can see two cores looking in through the radiator cap, but only 1 looking in through the driver side top hose inlet.

It still flows okay, and hovers right at 185-190 going down the road. There is some "junk" in the coolant when I drain it, little black "pebbles" if you will. Pieces of dirt. I screen them out each time.

With the intake just back on, I figured this would be a perfect time to flush/clean out the radiator. Prestones Superflush or 10 minute flush doesn't seem to be carried around here anymore, not at parts stores, nor Walmart. Only the bars leak version.

Am I better off just circulating water through the system? Through searching, \some suggest Vinegar and water, others suggest Cascade(WHAT!?), and another suggested a pressure washer. I don't think the pressure washer is a good idea. I don't want a large chunnk of one of the deposits on the edge of the core to separate, not "dissolve" and then clog something. I guess that's my biggest question here, would that happen? Should I just flush the big stuff out with the hose, let it come out of the bottom radiator hose and call it a day?

I thought I would fill the system, put the hose in the radiator fill, start the car, and just let the water run fast enough to keep it up, and wash it out for a few minutes. That would get the "big chunks" out, right?

 

Any brand radiator flush will work fine.

 

If it were me, I would be back flushng the system. Prestone used to sell a back flush kit that contained a hose fitting that went into a heater line. Buy the back flush kit and and a sort piece of heater hose, splice the fitting into the heater hose line, connect the hose and back flush the system.

 

Do you think I should clean the radiator seperately? Fill it up with vinegar/water or the flush and let it sit, then flush that out, for the big particles in the radiator don't flow through the hole system on the way out?


Thanks. I'll look into it.

 

I would also remove all of the block plugs and run a whole lot of water through there to churn up as much sediment as possible. If you put a garden hose in the filler, and let 'er rip, you ought to get a god flow out those plugs, and a lot of turbulence in the block all around them (as well as a neat geyser from the filler - wear your bathing suit!).

- Eric

 

I would follow the directions on the bottle. I like the Prestone back flush kit, however he said he could not find one.

 

I'm with Eric on this one. I just flushed my system a few months ago. I started by draining it at the radiator, then running filling and draining it a few more times with just water. Then I pulled the radiator and just ran water through it until it was completely clear. Then I pulled the block drain plugs and was amazed at my how crud came gushing out of there. I ran water through the inlet over and over again with one side plug open and then the other until they were both flowing clear.

Change your radiator and heater core hoses too, maybe even the heater core itself since it's probably got some nasty juices in there and could be corroded and just waiting to spew into your car's interior!

 

So I took the radiator out. I filled it with vinegar, let it sit for an hour or so, drained it and refilled it again with more vinegar, this time hot/boiling. Radiator has been sitting full since about 6pm last night. I figure it'll sit there until I get home, I'll drain it out and look at it again. I can always boil some more vinegar and do it again. Will flush it out with hot water tonight.

Sorry, I didn't mean the back flush kit, I meant the flush solution. I found a cleaner/flush. It syas for heavy cleaning run it in the car for 300 miles. So I'll fill it up with distilled water and use that and see how that goes.

In the filler, you mean the radiator filler right? Could I accomplish the same thing with a garden hose in the thermostat hole on the intake? I have the radiator out, filled with vinegar to dissolve some of the crap.

Thanks. Sounds like a good plan. I'll try to back flush the radiator core before I replace it. Weren't you concerned with adding tap water into the system when flushing it out? An intake swap quickly turned into a week long extravaganza, ha.

 

Yes, and Yes, BUT a.) The thermostat has to be open for you to flush through it, which it won't be once you blast it with cold water, and b.) The normal flow direction is in through the water pump and out through the thermostat, so if it's running, it'll need water coming in from the bottom.


Nope. Doesn't matter at all.

Show me where, in factory literature or on the antifreeze or flush solution label it says to use distilled water.

- Eric

 

Get a couple of these, one in 5/8 & another in 3/4. Also get some heater hose, about 6" in both sizes. Also get a 5/8 to 3/4 hose union. You'll be able to flush any car with this set up as it hooks directly to a garden hose, no need for a tee that might fail sometime later.

 

Well I found the water jacket bolts next to the freeze plugs, but they wouldn't budge. I put even tried a breaker bar and nothing. I thought about kicking it and trying to 'jar' is loose, but I didn't want to snap the head off. So I left it alone.

I removed both heater core lines, and flushed water in both ways. Some coolant came out, not a lot, and then it was clear water almost immediately. Maybe 1-2 seconds of fainly tan colored water/coolant. So the heater core is probably pretty good.

It was getting late and I wanted to drive the car tonight so I started reassembly. I'll add 2 bottles of the prestone cleaner/flush with distilled water and let that circulate for a couple of days. Hoping to go on a small road trip for the 4th and put a couple hundred miles on the car. Should be long enough to clean and remaining crap out.

3 Gallons of Vinegar later the radiator is about as clean as it'll get. Adding boiling Vinegar to the radiator and keeping a probe for and engine heater submersed in it kept the Vinegar nice and warm and it worked better. Most, if not all of the crud is off of the end of the cores in the rad. It's only a 2 core radiator, so every bit will help.

Will post back after my roadtrip when I drain the water/cleaner mix. We shall see.

 

I use a large truck water filter system and stick it in the heater hose coming out of the block and leave it there for maybe a week or so (of daily driving) and if the system is really dirty the filter will be plugged, so no heat, then add new filter and see what happens...but filters are about $10 bucks each the filters have a rust inhibiter in them...after a while the coolant looks very clear. This is with the anti-freeze still in system.

 

Thats a good idea, putting a filter in line with the heater hose.

My radiator looks good. Between the vinegar sitting for 2 days, and the radiator cleaner, it looks clean, there are a ton of little black specs in the water/cleaner mix which should come out when I flush the system again. Gotta either get those block plugs removed some how without breaking them, or use the T.

But the better, more exciting news is, AFTER 200 MILES, THE INTAKE GASKET END SEAL ISN'T LEAKING!!! WHOOP WHOOP.