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Thread: Full coolant flush tips?

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    Full coolant flush tips?

    unbolt engine block bolt?
    turning on the van with heater on high?

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    Re: Any tips on a full coolant flush on a 4y?

    Last time I had a complete flush, it was done by my NAPA garage. Yes, it wasn't cheap, $184 WOW(!), included the refill. But the crap that came out was UNBELIEVEABLE!!! Scale, rust and some stuff I've never seen! I have always used distilled water. The flush equipment is made by Gates and has only been out for roughly a year. They wanted to refill with the OEM Toyota antifreeze, but at $75 a gallon, I was told that it was discounted for me(?), I asked for the green stuff that I have always used. If you can afford it, it's worth it! Make sure it's the Gates System. The mechanic said that it has saved a few cooling systems. What else would expect them to say! Again on my high milage '95 Alltrac SC/LE it deserved it!
    Quote Originally Posted by highwind View Post
    unbolt engine block bolt?
    turning on the van with heater on high?

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    Re: Any tips on a full coolant flush on a 4y?

    Quote Originally Posted by kiowa View Post
    Last time I had a complete flush, it was done by my NAPA garage. Yes, it wasn't cheap, $184 WOW(!), included the refill. But the crap that came out was UNBELIEVEABLE!!! Scale, rust and some stuff I've never seen! I have always used distilled water. The flush equipment is made by Gates and has only been out for roughly a year. They wanted to refill with the OEM Toyota antifreeze, but at $75 a gallon, I was told that it was discounted for me(?), I asked for the green stuff that I have always used. If you can afford it, it's worth it! Make sure it's the Gates System. The mechanic said that it has saved a few cooling systems. What else would expect them to say! Again on my high milage '95 Alltrac SC/LE it deserved it!


    Ya, I have 2 bottles of Coolant Flush (bought that coolant flush kit too) \ running in the system for about 3 days now and I also filled up on some new yellow coolant. Ive been running around town with the heater on (to get the coolant flush running through the heater core) There is something Im very very concerned about is the people who are using the traditional yellow coolant. I came over from the MR2 Forum and they STRICTLY use the Toyota Coolant (red) because it has more additives in the coolant, (aka no headgasket failure) Not sure how "myth-y" this is.

    I have a bunch of Toyota Red Coolant here and I live in Florida so I dont need to use as much coolant as other places (But I plan on moving to Portland, Oregon)

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    Re: Any tips on a full coolant flush on a 4y?

    Everybody likes to see clean coolant in the recovery bottle and/or when pulling the radiator cap. These flushes and/or chemicals only help keep properly maintained systems clean. If the system has been neglected or abused (never changing coolant, mixing incompatible coolants, or running straight water), these processes and chemicals are not enough (will only get rid of the super fine or "silty" parts of the contamination). The big stuff stays behind and can only be cleaned after engine removal/disassembly. I recently tried flushing an engine that had the cooling system abused by the PO. It had been run with water only for several years. I used the Prestone chemical flush product and flushed it using the flushing tees & garden hose method. Water came out dark brown initially but after over an hr of flushing it turned clear. After flushing I filled with new coolant & drove it. The coolant almost immediately turned dirty again and overheating issues persisted. I removed engine, tore it down, knocked out the freeze plugs and here is what I found:







    And the pile you see there is only a fraction of what was in there. I blasted this thing with a pressure washer from all different angles and from all directions. After that I reassembled the engine with many new parts (documented here) and now it runs as cool as a cucumber. I've put around 7k miles on it so far & all is well. Tim

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    Full coolant flush tips?

    Is the the proper coolant for our vans or is there something special for high mileage or intense heat?--

    http://www.amazon.com/gp/product/B00...290_em_1p_1_ti

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    Re: Full coolant flush tips?

    I'm indifferent to the brand antifreeze you use. As long as it meets the minimum OEM requirements and you change it every 2 or 3 years it's fine. Toyota brand is a bit expensive, but it certainly meets these requirements . Tim

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    Re: Full coolant flush tips?

    Tim,

    I had the coolant flushed out about 2 years ago on my 2wd Van but when I took it in for service they told me the water to coolant ratio was too high and it need to be flushed again. It still runs cool with the temperature needle 2-3 ticks below the half way line. But since you said flushing every 2-3 years I'm guessing it's time but I'm not interested in paying $165 for a coolant flush....sheesh!!!

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    Re: Full coolant flush tips?

    Flushing is what you do when trying to compensate for years of neglect. Assuming your cooling system hasn't previously been neglected/contaminated, if you change coolant every 2 - 3 years, and don't intermix different types of coolant, then you don't need to flush. Just drain out the old and put in the new. Sometimes I'll let my coolant go longer (up to 5 years) but if you do that it's a good idea to check ph. The problem with leaving the coolant in too long is it can become acidic. If that happens it will start eating away at gasket material and aluminum parts. Tim

    PS: If you're changing types of antifreeze, then it's a good idea to flush as it's never a good idea to mix different types.

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    Re: Full coolant flush tips?

    Thank you for the attention to detail on not mixing coolants, I'm not sure what kind was used when my now retired Tech preformed the initial full service on the Van so it looks like a flush will be due to factor out the uncertainty.

    So the recommendation from the shop said-

    "coolant protection is +20 degrees and rusty and recommend flushing"

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    Re: Full coolant flush tips?

    That sucks, sounds like the last flush was not done correctly. If it looks rusty you need to clean it out (flush) ASAP as this means you're already on your way to trouble. The correct freeze protection should be -32. To have less freeze protection means you have less corrosion protection (there's not enough concentration for the corrosion inhibitors to do their job). Here's an extreme example of what can happen if the system is neglected/abused for too long:

    This is what I found behind the freeze plugs during an engine overhaul (and this was AFTER a thorough coolant flush):

    The above engine only had 150k miles on it.

    It's best to drain the block and the radiator after a flush so you can get the water out. Here's where your block drain plug is located:


    You can use the drain plug on the radiator to empty that, but I usually pull the lower radiator hose off the radiator nipple as that will drain more thoroughly. When it comes to left over water in the system, different water sources will have different acidic and/or mineral content, so unless you want to start out with questionable PH, it's just best to drain and use a 50/50 premix. If you would rather roll the dice (don't drain), you should use a concentrate antifreeze to compensate for the water that got left behind (sounds like the last guy didn't do that). Personally, I like to drain then use Extended Life green Prestone 50/50 (but other brands/types are good too). When I was talking about not mixing types, I meant not mixing different colors (IE: don't mix orange with green or yellow or red etc). In some cases it's okay to mix green & red, but you need to know if the additives are compatible (never mix inorganic additives with organic kinds). It's usually okay to mix different brands of the same colors (although there are some exceptions so I would try to avoid it). It's best to pick a brand/type that meets OEM specs, flush once, then use this same stuff from that point on. The problem with mixing is not all additives will work together. If you end up with a compatibility issue the additives may counteract each other or come out of suspension and fall to low points of the system (turning into sedatives & leaving your engine unprotected). There's lots of information on the net. Just Google search "different types and colors of automotive antifreeze".

    If you use a concentrate, in order to maintain correct PH, I would recommend using distilled water to mix. FYI, you can get PH test strips at most auto parts stores. Tim

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    Re: Full coolant flush tips?

    Excellent illustrations thank you. Looks like I'll be flushing it just too eliminate the risk of the first nightmare photo of the clogged freeze plug, Nooooo thank you I don't wanna deal with that!!!

    lets see if I have the order of operation correct-
    1) with engine cool release pressure from radiator cap
    2) unclamps lower raitator hose and drain
    3) attach lower radiator hose
    4) fill with distiller water and run engine to mix leftover coolant
    5) unclamp lower hose and drain
    6) attach lower hose
    7) fill with 50/50 extended life coolant at the radiator cap

    I'm scared to open the freeze plug cause 1) probably can't reach it from where it's located and 2) might not torque it down properly and have another issue down the road.

    I heard to get the leftover coolant out that you can even use a radiator pressure tester to push the coolant out of the block and not have to open the freeze plug? Does that sound right or dangerous to the internals cause they like to work with the natural flow of gravity and not be pushed and pressured out?

    Thank you
    Attached Images Attached Images  

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    Re: Full coolant flush tips?

    To drain the block you don't need to remove freeze plugs, just take the 14 mm brass bolt/plug loose (circled in above picture) and the block will drain. This is a tapered brass plug that seals itself on the taper when it's tightened back up, so very little chance of creating a leak by taking it out and putting it back in. The bad part is access. It can be frustrating (especially on a 4wd) but not impossible to get it in/out (this is due to the terrible placement between the alternator and motor mount).

    Here's a post I made a while back explaining how to flush: http://www.toyotavantech.com/forum/s...=2735#post2735

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    Re: Full coolant flush tips?

    Tim thank you for the redirect link

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    Re: Full coolant flush tips?

    Quote Originally Posted by timsrv View Post
    To drain the block you don't need to remove freeze plugs, just take the 14 mm brass bolt/plug loose (circled in above picture) and the block will drain. This is a tapered brass plug that seals itself on the taper when it's tightened back up, so very little chance of creating a leak by taking it out and putting it back in. The bad part is access. It can be frustrating (especially on a 4wd) but not impossible to get it in/out (this is due to the terrible placement between the alternator and motor mount).

    Here's a post I made a while back explaining how to flush: http://www.toyotavantech.com/forum/s...=2735#post2735
    Hey Tim, I just yesterday did a flush, but not quite as thoroughly as I would have liked (I couldn't find the 5/8 tee you mentioned in your writeups so I just put the hose in the radiator fill cap and ran it until the water came out clear after draining, closed everything back up, ran it for 15 minutes with water and a flush solution, drained again, "flushed" again, filled with water, ran for 15 minutes, drained and refilled with coolant and distilled water, but for some reason I only managed to get just over 5 litres in including filling the overflow tank to the full line. Is there some kind of reservoir that I could somehow have failed to drain? There was a fair bit of scale in the coolant I flushed but no rust, didn't strike me as horribly severe corrosion. I replaced the greenish yellow coolant the PO had put in with Beck Arnley red toyota coolant so I wanted to be sure I got all the green stuff out, and I'm pretty sure I did, but if there's almost 3 litres of mystery liquid (either coolant or undistilled hose water) I'm a little concerned. Any ideas? Thanks!

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    Re: Full coolant flush tips?

    If you pulled the block drain and drained the radiator that should be all of it. Sometimes a vacuum can cause some to stay in the system, but you should have gotten most of it. After all is said and done, the part that matters is the concentration. You should have ~-34F protection. You can buy a cheap antifreeze hydrometer at any auto parts store to test freeze protection. If it doesn't have good freeze protection then drain some out and replace it with concentrate. run and test again until you get it right. Tim

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    Re: Full coolant flush tips?

    Good idea! I'll pick one up. Thank you

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    Re: Full coolant flush tips?

    Quote Originally Posted by Wrench View Post
    ... drained and refilled with coolant and distilled water, but for some reason I only managed to get just over 5 litres in including filling the overflow tank to the full line.
    I just went through this and am fairly confident that my cooling system was fully filled with distilled water. I only got ~6 liters to drain out via the radiator, block, and full overflow reservoir. I assume there are still ~1.9 liters (4wd with rear heater, 7.9 liter capacity) in the hoses, lines and heater cores. Unless somebody advises me against this, I am going to account for that 1.9 liters of water when I make my 50/50 mix.

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    Re: Full coolant flush tips?

    That's how I always do a flush and fill. Flush and drain. Calculate half the system capacity and add that volume as antifreeze concentrate. After that top with straight water. Then I fill the reservoir with a 50/50 mix. Add more 50/50 to the reservoir as needed after heat/cool cycles. You'll never get all the water out so best to factor it into the equation.

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    Re: Full coolant flush tips?

    Tim, i think im having a similar issue as that engine you pulled the freeze plugs on. Ive flushed out my vans block many many times and lots of chunks came out. I flushed it til nothing else came out. The radiator, t-stat, and water pump are all new. Still when i try running it the temp guage just keeps on climbing, and the radiator does not get warm to the touch. However the front heater core does get warm. I took the throttle body off and found that its coolant passage was blocked. I unblocked it, but i still have to unblock the metal pipe that goes from throttle body (Under the air manifold) back to the block. Thats where im at right now. I am suspecting that the block is still clogged somewhere. Is it possible to pop the freeze plugs out without pulling the engine? Any advice helps. Thanks! James
    P.S. My van is an 86 van le 2wd auto.

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    Re: Full coolant flush tips?

    They can be removed, but you'd need to tear down the D/S of the engine (manifolds included). When I cleaned my engine it was on a stand, completely torn down to just a bare block. I used a pressure washer and sprayed from all angles with block in different positions (upside down, sideways, etc). Each time I repositioned and resprayed I got more junk out. I think it would be very hard or even impossible to clean to that same degree with the engine in the chassis. The restricted access would also make it tough to resurface the plug holes and press new plugs in. You could always go with the rubber plugs, but those IMO are just temporary as the block will rust where the rubber contacts it and will eventually start leaking. Tim

    To see more details of freeze plug replacement see THIS POST

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