Radiator flush

[john saleeby]

Does this sound like a proper way to flush?

Drain coolant
refill with water from garden hose
remove upper radiator hose from radiator side
start car
leave garden hose in radiator with flow from garden hose matching flow of water exiting the top radiator hose.

Also, any good results using powdered Cascade dishwashing detergent?

 

[Squid4life]

That might work if you remove the thermostat. I just did mine by draining coolant (water in my case), filling with clean water, and opening the petcock. Had hose barely running in the top of the rad to keep filled. Either that or drain it, fill it with water, run it through, drain it, repeat.

I also used prestone rad flush, adding some water, and driving 6 total hours as suggested. Then drained and filled with water.

Kind of hard to flush "pressurized" with the thermostat in.

 

[oldsracer]

That might work if you remove the thermostat. I just did mine by draining coolant (water in my case), filling with clean water, and opening the petcock. Had hose barely running in the top of the rad to keep filled. Either that or drain it, fill it with water, run it through, drain it, repeat.

I also used prestone rad flush, adding some water, and driving 6 total hours as suggested. Then drained and filled with water.

Kind of hard to flush "pressurized" with the thermostat in.

This is the best way to do it. At my shop we usually open the petcock drain the radiator cold, run garden hose water through it cold until its clean coming out the bottom.(MUST BE COLD,IF RADIATOR IS HOT COLD WATER IS A DEATH WISH). Close petcock and fill the radiator first with some sort of radiator cleaner and water as directed to. Drive until the car fully warms up and heats up fully. Wait for it to cool off then open the petcock and drain the fliuds and observe how clean the fluid is. Then we usually do another cycle of just garden water (depending on how dirty it is/was). Then fill back up with antifreeze and water and check for leaks. We usually will only use one bottle of cleaner because customers dont like when you gotta use two...But again, it is very important to keep the motor cool or cold because cold water and a hot motor or radiator is asking for cracks and bursts. You can keep doing this as many times as you wish to get everything cleand out but take your time. This is a time consuming process but done right youll only have to do it once.

 

[Nick Micale]

This may not be the best way, but just what has been learned after 25 years of keeping TR cool during the long, hot desert summers.

We have found the commercial radiator flushes and and cleaners are caustic and acidic which is not only harmful to cooling system materials, but are EXTREMELY difficult to completely remove from the system.

The procedure which has evolved to work the best for us is to first drain the old, and probably dirty fluid from the system. Then fill it with water and add 8 oz. of RMI-25 and drive it 200-300 miles, or until lots of brown crud is around the radiator cap.

Drain and flush again. This time disconnect the heater hoses and flush, as well as back flush, the heater core with a garden hose. This can take 15-20 minutes to clear out the crud.

Also, as an option to removing the t'stat. we remove the lower hose from the radiator when flushing the block.

This is where there is a big problem when using chemical flushes, the poor circulation with the 90 deg. bends trap it in the core, and other junk from the system as well which slowly works back into the cooling system and eventually causes damage.

With the heater hoses disconnected, you can also back flush the block using the heater hose that enters the intake manifold.

RMI-25 is the only additive that will actually clean the cooling system, block, radiator, heater core and all else while you drive. Since it also protects the cooling system from corrosion, it can be used year around even with antifreeze in the cold temps.

Remember, antifreeze will run hotter in the summer, so best to change fluids twice a year in that case.

Once you do a "complete" flush and use RMI, the cooling system will be trouble-free for many years. We have proven this with many GN using RMI over 15 years with radiators that are still clean as new, and no build up on tubes or anywhere in the system.

 

[GN owner]

This may not be the best way, but just what has been learned after 25 years of keeping TR cool during the long, hot desert summers.

We have found the commercial radiator flushes and and cleaners are caustic and acidic which is not only harmful to cooling system materials, but are EXTREMELY difficult to completely remove from the system.

The procedure which has evolved to work the best for us is to first drain the old, and probably dirty fluid from the system. Then fill it with water and add 8 oz. of RMI-25 and drive it 200-300 miles, or until lots of brown crud is around the radiator cap.

Drain and flush again. This time disconnect the heater hoses and flush, as well as back flush, the heater core with a garden hose. This can take 15-20 minutes to clear out the crud.

Also, as an option to removing the t'stat. we remove the lower hose from the radiator when flushing the block.

This is where there is a big problem when using chemical flushes, the poor circulation with the 90 deg. bends trap it in the core, and other junk from the system as well which slowly works back into the cooling system and eventually causes damage.

With the heater hoses disconnected, you can also back flush the block using the heater hose that enters the intake manifold.

RMI-25 is the only additive that will actually clean the cooling system, block, radiator, heater core and all else while you drive. Since it also protects the cooling system from corrosion, it can be used year around even with antifreeze in the cold temps.

Remember, antifreeze will run hotter in the summer, so best to change fluids twice a year in that case.

Once you do a "complete" flush and use RMI, the cooling system will be trouble-free for many years. We have proven this with many GN using RMI over 15 years with radiators that are still clean as new, and no build up on tubes or anywhere in the system.

 

[GN owner]

NIck,

I was doing a search on the best method and/or chemical to use in order to flush the cooling system because recently I noticed that the engine was running hotter than usual. In trying to get to the bottom of this problem I noticed that around the radiator cap there was a lot of brown soft mud like crud so this crud must be clogging up the water passages and radiator. I use a mixture of RMI-25 and some anti-freeze. The coolant is still green and somewhat transparent so the coolant is not as contaminated as I first thought. So what I gather from reading your post is to remove the lower radiator hose and the heater hoses and flush the cooling system until all of the coolant comes out clear. Then add 8 oz of RMI-25 and drive around for 300 miles or so and then drain/flush the system again and then just add RMI-25 and I should be good to go. Do you think it would be beneficial to do this a couple of times as I want my cooling system to work like it was a few months ago when the engine was not running hot since we are on the tailend of summer here and its been hot lately. Thank you for any added comments you may have for me.

Thank you very much,
GN owner

 

[Nick Micale]

NIck,........... Do you think it would be beneficial to do this a couple of times as I want my cooling system to work like it was a few months ago when the engine was not running hot since we are on the tailend of summer here and its been hot lately. Thank you for any added comments you may have for me.

Thank you very much,
GN owner

The RMI will clean the cooling system while you drive, and it will keep the crud in suspension until the solution becomes saturated and you will see the crud accumulate around the radiator cap.

It is then time to flush the system and again add RMI. When the system is then relatively clean, it will remain that way with the continued use of RMI.

If you are in an area with freezing temps, it is a good idea to add a RMI treatment with the fresh antifreeze and it will continue the cleaning process as well as supplement the minimal additive package contained in antifreeze.

Since antifreeze will not transfer heat as well as plain water, our recommendation is to flush the antifreeze every Spring, and go with water and RMI until the Fall.

With local T-R's using RMI-25 over most of their lives for about 20 years, we very seldom see cooling system issues even with our blazing hot summer months which can take a tremendous toll on engine and transmissions as well!

 

[TLIMITED]

The RMI will clean the cooling system while you drive, and it will keep the crud in suspension until the solution becomes saturated and you will see the crud accumulate around the radiator cap.

It is then time to flush the system and again add RMI. When the system is then relatively clean, it will remain that way with the continued use of RMI.

If you are in an area with freezing temps, it is a good idea to add a RMI treatment with the fresh antifreeze and it will continue the cleaning process as well as supplement the minimal additive package contained in antifreeze.

Since antifreeze will not transfer heat as well as plain water, our recommendation is to flush the antifreeze every Spring, and go with water and RMI until the Fall.

With local T-R's using RMI-25 over most of their lives for about 20 years, we very seldom see cooling system issues even with our blazing hot summer months which can take a tremendous toll on engine and transmissions as well!

Hey Nick,Where can I buy the RMI-25?Do any local parts chains carry it?

 

[earlbrown]

Oh hell no. That stuff is almost as rare as unicorn blood, but but not quite as hard to find as orphan tears. You won't find it over the counter.



...and nothing wakes up a sammich like unicorn blood and orphan tears.

 

[1fastcobra]

Check out this item I found on eBay: http://pages.ebay.com/motors/link/?nav=item.view&id=181503669621&alt=web

Allways good to keep a little extra on hand

 

[TurboSmart]

I use a oil based house cleaner called LestOil, will be doing this on my GN this week..

On a cold engine, drain the radiator, add a 16oz bottle and fill it with water, leave rad cap off
Start the car and warm it up, leave it idling for lie 15 to 30 mins tops.

Then, with the car running, open the petcock a little bit, just to dribble water and add fresh water for 30 mins or so.

Shut off the car, and remove lower hose from the rad. Let it drain....

Let it cool down a little bit,
Add water to the rad with the hose removed, let it flush...

Remove upper rad hose and fill the engine with water slowly, let if flush thru the lower rad hose.

Reconnect hoses, fill it with plain water and start engine until warm, keep the water hose inside the radiator, filling it.

Remove the lower rad hose, cap radiator hose (usually I flip the hose) and continue to add water until is clear.

Then, shit off car, let the water flow to help cool the engine.

Reconnect clamps, hoses, etc.. fill the radiator with coolant (pure, no mix as there is water in the engine block)

Start car and check mixture, add water or coolant as needed.

Drive the car to burp the system, add as needed.

 

[whitehot1]

If you go on ebay to buy the RMI-25. You will get a lot better deal buying it in one 32 oz bottle than you will in four 8oz bottles. I just bought some last month and the price is still the same this month. And don't worry about having extra you will use it. As far as adding it to the cooling system an 8 oz bottle will treat a 5 gal cooling system so you don't really need to use an whole 8 oz bottle in a GN cooling system. If your cooling system is fairly clean and not full of crud you could just add the RMI-25 without draining and flushing the system and it will maintain the cooling system to keep it clean as you drive.