Coolant Flush

There have been quite a few "new" TR owners join in
the past few months. So I'm gonna post a basic question
of two parts for all us newbies to the TR mechanical world.

1. What is the proper procedure to drain and flush
the radiator and cooling system of the TR cars?
A. for example- thermostat in or out?
B. Engine running, drain open?
C. etc ...............



2. How can one determine the thermostat opening temperature,
like what model thermostat do I have?

thanks,

dale

To drain the engine you remove the radiator cap, open the plug on the bottom of the radiator (or if there isn't one, slip off the lower water hose. On the left side of the engine, about 1/2 the way down, toward the back there is a plug which will let the water out of the block.

This should let all the water out.

Now if you take the plug out you can put a stiff wire in and poke around. See what comes out. If you get allot of crude out keep poking. You can also take the water pump housing off and poke around the water passages in the top of the head. Rinse it all out. A high pressure water sprayer is great for this. Short of pulling the engine apart there is not allot else you can do to the engine block.

You can also force water through the radiator backwards by putting a hose in the bottom, and sealing it with a rag and then opening up the water full blast. If there is loose crud it may come out, but if there really is stuff stuck in it, it is better to have a radiator shop clean it properly.

Do not run the engine without water or while you are draining the engine! I will most likely ruin it!

The easiest way to find out what temperature thermostat you have is to just look at it. it is stamped on the thermostat. You can test it by putting it into water and heating it, with a thermometer as a comparison. As it approaches the temperature stamped on it, it should visibly open up. Given the fact that they are rather cheap I would just buy a new one. The local parts place should have them.

To drain the engine you remove the radiator cap, open the plug on the bottom of the radiator (or if there isn't one, slip off the lower water hose. On the left side of the engine, about 1/2 the way down, toward the back there is a plug which will let the water out of the block.

This should let all the water out.

Now if you take the plug out you can put a stiff wire in and poke around. See what comes out. If you get allot of crude out keep poking. You can also take the water pump housing off and poke around the water passages in the top of the head. Rinse it all out. A high pressure water sprayer is great for this. Keep poking and rinsing until the water comes out consistently clean. You can also force water in from the drain hole. Short of pulling the engine apart there is not allot else you can do to the engine block.

You can also force water through the radiator backwards by putting a hose in the bottom, and sealing it with a rag and then opening up the water full blast. If there is loose crud it may come out, but if there really is stuff stuck in it, it is better to have a radiator shop clean it properly.

Do not run the engine without water or while you are draining the engine! I will most likely ruin it!

The easiest way to find out what temperature thermostat you have is to just look at it. it is stamped on the thermostat. You can test it by putting it into water and heating it, with a thermometer as a comparison. As it approaches the temperature stamped on it, it should visibly open up. Given the fact that they are rather cheap I would just buy a new one. The local parts place should have them.

Yisrael thanks,

"Back in the day" all of us poor folks drove clunker
cars that tended to overheat going up long, steep hills.

Once a year we would "flush" out all the rust. That
consisted of draining the radiator, filling it with the hose,
running the the engine for about 15 to 20 minutes with the
radiator spitcock open on the bottom and the hose filling
the radiator top opening.

Is this the correct procedure for flushing a Triumph?
Or will 15 minutes of constant cold water flowing thru
the engine do damage?

thanks,

PS: I didn't mean to start a cross thread on the
engine overheating issue.

d

Tinster said:

Yisrael thanks,

"Back in the day" all of us poor folks drove clunker
cars that tended to overheat going up long, steep hills.

Once a year we would "flush" out all the rust. That
consisted of draining the radiator, filling it with the hose,
running the the engine for about 15 to 20 minutes with the
radiator spitcock open on the bottom and the hose filling
the radiator top opening.

Is this the correct procedure for flushing a Triumph?
Or will 15 minutes of constant cold water flowing thru
the engine do damage?

thanks,

PS: I didn't mean to start a cross thread on the
engine overheating issue.

d

Click to expand...

It all depends on what the goal is. This will get out most of the loose rust. Running it cold is not the best thing, but shouldn't really do to much damage either.
I think you should at least poke around the block drain with a wire and see what comes out. If it looks like there is crude, spend the time to get out as much as possible. Otherwise, just flush it out as you suggest and put in nice clean antifreeze. The suggestion to use a 75/25 mix is good. replace it yearly since there is less of the protective chemicals in there.

70herald said:

To drain the engine you remove the radiator cap, open the plug on the bottom of the radiator (or if there isn't one, slip off the lower water hose. On the left side of the engine, about 1/2 the way down, toward the back there is a plug which will let the water out of the block.

This should let all the water out.

Now if you take the plug out you can put a stiff wire in and poke around. See what comes out. If you get allot of crude out keep poking....

Click to expand...

Everything Yisrael said, except that the drain plug (or, on some cars, a petcock) is on the right-hand side of the engine. Triumph may have been onto something when they switched from a block petcock to a plug, inasmuch as this (in my opinion) is where most of the sediment will accumulate. It's easy to be fooled by a stream of water coming out of an open petcock. Many times I've seen that, removed the petcock and poked around only to eventually loosen gobs of sediment, after which the trickle or stream of water becomes a gusher. THAT'S what you want to see. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif If you don't get a gusher of water out of the engine block drain, you've still got buildup! /bcforum/images/%%GRAEMLIN_URL%%/frown.gif

.. and please be aware that antifreeze of any concentration is deadly to pets if they lick it or drink it.

I'll send our family dog right over>

[/quote]Everything Yisrael said, except that the drain plug (or, on some cars, a petcock) is on the right-hand side of the engine. [/quote]
it all depends if you are standing in front of the engine or behind it /bcforum/images/%%GRAEMLIN_URL%%/jester.gif How about near the exhaust manifold?

70herald said:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]...the drain plug (or, on some cars, a petcock) is on the right-hand side of the engine....

Click to expand...

it all depends if you are standing in front of the engine or behind it /bcforum/images/%%GRAEMLIN_URL%%/jester.gif How about near the exhaust manifold? [/QUOTE]That works for me! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif I'm used to citing locations as if one were sitting inside the car. (I could have said sitting in the driver's seat, but that also could be confusing depending on which side of the car the steering is on....)

PeterK-

Thanks for the info. I didn't know that.
We have three cats. One will drink from rain
puddles on the outdoor furniture.

Wendy would have my head if I poisoned one of of cats.

thanks,

d

My engine is a TR250-

I see a lever arm spitcock coming out of the block
directly over the starter motor.

Is this the block water drain device?

d

There are coolant flush kits available in most auto parts stores. Ones where you add their chemical to your system, run the engine for a specified period of time and then drain and backflush the system. The antifreeze sellers usually sell them. I've had good experience with them.
After the backflush then it's time for the new thermostat and radiator cap.
Also go to a parts store that sells for trucks. Diesel trucks use a "water wetter" additive that helps prevent cavitation in the system. Dunno if the water wetter sold at the discount stores is the same as the truck stores, that's why I recommend the trucks, either that or read the contents of the bottles from both sources then decide.

PeterK said:

.. and please be aware that antifreeze of any concentration is deadly to pets if they lick it or drink it.

Click to expand...

My dog won't touch it.

My engine is a TR250-

I see a lever arm spitcock coming out of the block
directly over the starter motor.

Is this the block water drain device?

d


Yes Dale, that's it.

RonMacPherson said:

There are coolant flush kits available in most auto parts stores. Ones where you add their chemical to your system, run the engine for a specified period of time and then drain and backflush the system. The antifreeze sellers usually sell them. I've had good experience with them....

Click to expand...

Yes, some are better than others, just like some automatic dishwashers are better than others. But it's a bit like that tuna casserole dish after dinner. It MIGHT get clean in the dishwasher, but you'll KNOW it gets clean if you put it in the sink and SCRUB it. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif It's still a good idea to do the "probe" thing. In your case, Dale, remove that petcock. With your track record thus far on Crypty, I don't know as I'd expect anything to flow through that drain...or if the drain itself isn't clogged up and/or ready to let go!

Andy- et al

I got super lucky on this one. I must have done
a fairly decent flush job when I replaced the blown
up radiator. Even though I was not aware of the
engine block spitcock at the time. I flushed it
maybe 4 times to get DPO Pedro's stop-a-leak goo
out of the system.

I bought a coolant flush product this afternoon.
When I took off the entire engine spitcock assembly
water strongly gushed out. I could get nothing
particulate out with a small screwdriver or with
a length of wire. No DPO Pedro crud at all.

My thermostat was made in France and is stamped
82* C. My radiator, radiator cap, hoses, thermostat,
temp sender and temp gauge are all new with less than
300 miles use on them.

Stupid question? Can thermostats be obtained anywhere?
Or must I order one from the Big Three?

regards,

d

AutoZone lists 15 choices with different temperature ranges.

Napa lists 18

Parts America lists 7

It crosses with a small block Chevy, which is a very common application. I believe the gasket is the same as well.

Interesting observation:

This morning I performed phase three of
the coolant system flush. Clear water
for ten minutes after the engine reaches
operating temperature.

The temperature pegged out at a constant 150* F.
A 30 degree drop from my normal 180* operating
temperature with 50% antifreeze or with the
flush chemical.

Proves Bill's statement that plain water removes
heat best.

I'll go in search of 165* t-stat and put back 25%
antifreeze and some slippery water additive if I
can find any on the island.

Now it's off to the mines for me to pay for Crypty's
maintenance.

d

Did you remember to open the heater valve, if not you've old stuff in the heater core. Watch for leaks under the dash