Let's baseline my grandma's neglected, (20 year old to us) 1997 LX450 (2 Viewers)

[bicycleagent003]

That water still looks pretty crummy to me. I would suggest a *gentle* backflush. I don't recall which hose you want to disconnect at the firewall, but you can search for that on Mud. Just be sure to use gentle pressure, there is another Mudder that is convinced he blew his HG by flushing his cooling system. If it were me, I would just use hose water (gentle pressure for backflush first) for the filling and running it around town to get it to operating temperature, run the heat on high to get the whole system circulating, then drain and refill. I would keep doing that until it looks clear, but if it doesn't get to clear then I think I would just starting taking it apart without putting good coolant in it. By taking it apart, I mean replacing the radiator, water pump, thermostat, heater control valve and hoses and clamps. That's just my take on it. Fun but time consuming, and costs will add up.
You have another vehicle, so it appears you can take your time with this. Hopefully time and funds are also sufficient.

 

[avdeveloper]

That water still looks pretty crummy to me. I would suggest a *gentle* backflush. I don't recall which hose you want to disconnect at the firewall, but you can search for that on Mud. Just be sure to use gentle pressure, there is another Mudder that is convinced he blew his HG by flushing his cooling system. If it were me, I would just use hose water (gentle pressure for backflush first) for the filling and running it around town to get it to operating temperature, run the heat on high to get the whole system circulating, then drain and refill. I would keep doing that until it looks clear, but if it doesn't get to clear then I think I would just starting taking it apart without putting good coolant in it. By taking it apart, I mean replacing the radiator, water pump, thermostat, heater control valve and hoses and clamps. That's just my take on it. Fun but time consuming, and costs will add up.
You have another vehicle, so it appears you can take your time with this. Hopefully time and funds are also sufficient.

yeah I'll pass on the backflush and just rely on the typical fill, run, drain. ok I bought some more water. I have the new parts you mentioned. should I get a new water pump while I'm at it then?

given that there might still be residue, I'm going to have to make a trip to the landfill to dump this water right? I've made two trips by now LOL

 

[bicycleagent003]

I actually didn't see how many miles you said are on the vehicle, but I would just replace the WP if it were me. I think an Aisin WP on Amazon is like $75. If you've already drained and filled it and you're just draining out contaminated water but not coolant, I would just pour it in the gravel/mulch on my own yard and let the sand filter it down. You're not pouring coolant in the ground, just water with gross bits in it (looks like rust to me). But that's just me.

 

[SaturnAscends]

yeah I'll pass on the backflush and just rely on the typical fill, run, drain. ok I bought some more water. I have the new parts you mentioned. should I get a new water pump while I'm at it then?

given that there might still be residue, I'm going to have to make a trip to the landfill to dump this water right? I've made two trips by now LOL

I was just asking about this on another thread where @BILT4ME said it took him 6 drain and fills with distilled water to get it draining out reasonably clean.

The only thing I'm not clear on is if you have to drain from the block each time, and if the dirty water still has to be disposed of at a parts store, as you already mentioned.

Anyway I'm in kind of a similar predicament. After seeing this I'm wondering if it's even worth all the trouble vs. taking it to a BG flush machine and just being done with it so you don't have to deal with like 12 gallons of toxic sludge.

 

[avdeveloper]

I was just asking about this on another thread where @BILT4ME said it took him 6 drain and fills with distilled water to get it draining out reasonably clean.

The only thing I'm not clear on is if you have to drain from the block each time, and if the dirty water still has to be disposed of at a parts store, as you already mentioned.

Anyway I'm in kind of a similar predicament. After seeing this I'm wondering if it's even worth all the trouble vs. taking it to a BG flush machine and just being done with it so you don't have to deal with like 12 gallons of toxic sludge.

yeah I mean at this point it might be cheaper to take it to the shop. but would they do the job if I told them to fill it with just distilled water instead of coolant because I'm going to take it apart anyway.

and yes I'm planning to drain it from the block right before I take it apart but I was contemplating on doing it sooner but would it be a mess?

 

[avdeveloper]

I actually didn't see how many miles you said are on the vehicle, but I would just replace the WP if it were me. I think an Aisin WP on Amazon is like $75. If you've already drained and filled it and you're just draining out contaminated water but not coolant, I would just pour it in the gravel/mulch on my own yard and let the sand filter it down. You're not pouring coolant in the ground, just water with gross bits in it (looks like rust to me). But that's just me.

right. I'll give it 3 more rounds and then if it doesn't change, it's safe to say that's no longer coolant. I'm about to reach 280k in mileage. I'll probably replace the water pump as well.

 

[SaturnAscends]

yeah I mean at this point it might be cheaper to take it to the shop. but would they do the job if I told them to fill it with just distilled water instead of coolant because I'm going to take it apart anyway.

and yes I'm planning to drain it from the block right before I take it apart but I was contemplating on doing it sooner but would it be a mess?

I’m not exactly sure as I’ve never attempted it before. Some claim you can quickly attach a 5/8” hose to the drain after loosening the bolt to direct the coolant into a container.

As far as the shop getting all the old stuff out, I’m not certain but the BG machines are theoretically supposed to remove most of the old stuff. I guess it all depends on how OCD you wanna get with it.

In any case I’d monitor the temps and coolant levels afterwards to make sure no sludging has occurred, and the system is bled properly, etc.

 

[avdeveloper]

so when I'm bleeding the distilled water I set my heater to hottest at low fan speed and rear heater to low as well. I just noticed this today but in past few days when I did the flushing, I didn't see this.

 

[avdeveloper]

Update: I was still running with distilled water in the pipes when I ran over a bump on the expressway at 75mph and exhaust came loose. I couldn't pinpoint where the noise was coming from so I had taken it into the dealership and got out with a loaner and a pricey invoice to have the entire exhaust system replaced because it turns out that the last time the exhaust was fixed, the aftermarket cats and muffler were just welded on. I was initially planning to DIY the replacement but given that the bolts/nuts are not going to come off cleanly, I'd rather pay for the time to have someone else do it. So I won't be able to continue with the flushing and dismantling until I get it back in two weeks.

 

[avdeveloper]

all right! grandma's cruiser is back from the shop with a full exhaust replaced with OEM. It's much quieter but is burning off the stickers that weren't removed during the installation so it smells.



Time to continue with the flush. I got the spout from wits end that will help me drain from the engine block as well to hopefully get me to clearer water faster.

I took a video of engine noise where the drive belts are. Does that sound normal or is the alternator noisy?

 

[florida95fzj]

I had to use Thermocure but it finally got the rust of my cooling system. Rust apparently is an insulator so it retains heat in places you'd like to cool. I am seeing temps in the 180s now and it only got to 195F briefly on a 100F day recently in stop-and-go traffic.

Before the Thermocure, the flushes were not productive and just created more waste that's a pain to dispose. I also did a garden hose flush and backflush followed by a few rounds of drain/fill with distilled water. IIRC, I flushed the heater core by itself. Then I was able to install the new water pump, radiator, and changed all of the hoses.

 

[avdeveloper]

I had to use Thermocure but it finally got the rust of my cooling system. Rust apparently is an insulator so it retains heat in places you'd like to cool. I am seeing temps in the 180s now and it only got to 195F briefly on a 100F day recently in stop-and-go traffic.

Before the Thermocure, the flushes were not productive and just created more waste that's a pain to dispose. I also did a garden hose flush and backflush followed by a few rounds of drain/fill with distilled water. IIRC, I flushed the heater core by itself. Then I was able to install the new water pump, radiator, and changed all of the hoses.

thanks for the tip. I just ordered it. I saw the sediments from my previous flushes drop to the bottom and the water on top is clear. I guess those would be the rust build up. I'll try flushing the heater core by itself.

 

[florida95fzj]

thanks for the tip. I just ordered it. I saw the sediments from my previous flushes drop to the bottom and the water on top is clear. I guess those would be the rust build up. I'll try flushing the heater core by itself.

The directions are a bit fuzzy to me but I think it turns the water black. Darker means more rust. I believe you're supposed to see a temp reduction while running with that stuff in the system but I didn't see a big improvement until after I changed all of the parts. I can't say if getting rid of the rust actually made a big cooling difference. My goal was to only to keep the rust/sediment out of the brand new radiator. Pretty sure I posted some pictures in a thread here.

I have to admit I was half surprised all of the work actually paid off. I was concerned the corrosion was so massive there was no coming back. Once I started changing hoses, I learned I also had to replace a lot of expensive hard pipes due to deterioration. The process had the truck down much longer than I wanted but it was worth it.

 

[avdeveloper]

The directions are a bit fuzzy to me but I think it turns the water black. Darker means more rust. I believe you're supposed to see a temp reduction while running with that stuff in the system but I didn't see a big improvement until after I changed all of the parts. I can't say if getting rid of the rust actually made a big cooling difference. My goal was to only to keep the rust/sediment out of the brand new radiator. Pretty sure I posted some pictures in a thread here.

I have to admit I was half surprised all of the work actually paid off. I was concerned the corrosion was so massive there was no coming back. Once I started changing hoses, I learned I also had to replace a lot of expensive hard pipes due to deterioration. The process had the truck down much longer than I wanted but it was worth it.

yup same reason for wanting to remove the rust. I don't want that contaminating the new parts I'll be replacing with.

 

[avdeveloper]

The directions are a bit fuzzy to me but I think it turns the water black. Darker means more rust. I believe you're supposed to see a temp reduction while running with that stuff in the system but I didn't see a big improvement until after I changed all of the parts. I can't say if getting rid of the rust actually made a big cooling difference. My goal was to only to keep the rust/sediment out of the brand new radiator. Pretty sure I posted some pictures in a thread here.

I have to admit I was half surprised all of the work actually paid off. I was concerned the corrosion was so massive there was no coming back. Once I started changing hoses, I learned I also had to replace a lot of expensive hard pipes due to deterioration. The process had the truck down much longer than I wanted but it was worth it.

this should do the trick for flushing the heater core right?

 

[florida95fzj]

I did something similar. I bought a fairly inexpensive hose nozzle off Amazon that would jam tight into the spare hose and let me control the pressure. There's lots of good ways to do this.

 

[avdeveloper]

so I'm working on replacing the drain plug on the engine block with this nice gadget from wits end, and I'm having trouble finding it. the vague picture from the FSM says it's on the left side of the cylinder block.

Is this bolt on the picture the plug?

 

[florida95fzj]

That's tough to say. Is that the driver's side? I don't recall anything being in the way and I see some kind of wire in the picture.

 

[COYS]

Well done replacing the full exhaust. I just did mine including new manifolds. I didn't notice much of a difference.

Your overall engine noise is much louder than mine.

 

[avdeveloper]

That's tough to say. Is that the driver's side? I don't recall anything being in the way and I see some kind of wire in the picture.

yes its on the driver side