RWC Engine temperature question

[Ajax]

Gents-

What is the expected engine operating temperature with a wide open system (no thermostat or adjustable ball valve) on a RWC engine with ambient water temp at around 60F?

I'm trying to verify that I've adequately flushed the crud out of my exhaust manifold. I *was* running at 120-140F with insufficient exhaust water and a lot of steam.

After power flushing the engine, I am down to 100-110F, at WOT, with little or no steam and more exhaust water. Am I there yet, or do I need more flushing?

Thanks.

[joe_db]

Sounds fine to me.
If the exhaust manifold is the issue and not the entire engine it is easy enough to remove and boil out if it gets clogged again.

Gents-

What is the expected engine operating temperature with a wide open system (no thermostat or adjustable ball valve) on a RWC engine with ambient water temp at around 60F?

I'm trying to verify that I've adequately flushed the crud out of my exhaust manifold. I *was* running at 120-140F with insufficient exhaust water and a lot of steam.

After power flushing the engine, I am down to 100-110F, at WOT, with little or no steam and more exhaust water. Am I there yet, or do I need more flushing?

Thanks.

[JOHN COOKSON]

Ajax
You're good on the temp. You're running only 40 or 50 degrees over the ambient water temp.
After I rebuilt the cooling system on my RWC A4 that has a thermostat I run ~ 70 or 80 degrees over the raw water temp. That is if the water temp is 70 degrees I run ~ 145 to 150. I'm happy with things the way they are.
As I'm sure you know if the temp is too low for you the way things are you can you can put a thermostat in and raise the running temp.
Did you try to localize where the blockage was? Or did you just pressure flush the whole shebang? The manifold has been mentioned and certainly is a prime suspect. You can localize the blockage by disconnecting hoses and seeing where the water flow is decreased.

TRUE GRIT

[Ajax]

John-

I had done two acid flushes of the engine.

It seemed that output from the hose connecting to the exhaust manifold (from the t-stat housing) was sufficient, but I had very little exhaust water and a lot of steam, and the manual indicated a clogged exhaust manifold in that case. I suppose the crud from the cooling jacket had been pushed into the exhaust manifold.

So, I power flushed the exhaust manifold with fittings and garden hose as prescribed. Some solid bits of junk flushed out and the color was very rusty. After about 10 minutes, everything was clear.

Even though I had enough output from the t-stat housing hose, I flushed the block and also got some solid bits and funky colored water for a while. Once the water was clear and without solid crud, I stopped.

That's where I am now. I motored for awhile yesterday with the system wide open, and couldn't get the engine any hotter than 110F. My OEM thermostat is DOA. I'll either buy the manual ball valve setup from Moyer or the Indigo t-stat kit. I haven't decided which one, yet.

[Jimmy]

Ajax
For what it's worth, I would go with the ball valve kit......in fact I did.
After my first season, of removing the T-stat for winterizing, I was sold!

I adjust the valve a couple times a season.as the lake starts around 50 degrees in April, and peaks around 75.

The still good T-stat lives it life in a zip lock bag, stored with other spare parts.

Cheers

[Ajax]

Ajax
For what it's worth, I would go with the ball valve kit......in fact I did.
After my first season, of removing the T-stat for winterizing, I was sold!

I adjust the valve a couple times a season.as the lake starts around 50 degrees in April, and peaks around 75.

The still good T-stat lives it life in a zip lock bag, stored with other spare parts.

Cheers

Your point about the mess of winterization is well made. However, I intend to convert to FWC at some point, and would no longer need to remove the t-stat.

I always thought that the ball valve was kind of "Rube Goldberg" compared with having a proper thermostat to regulate engine temperature, but I'm re-evaluating that opinion.

[joe_db]

It needs attention every now and again, but it does work and is cheap too

Your point about the mess of winterization is well made. However, I intend to convert to FWC at some point, and would no longer need to remove the t-stat.

I always thought that the ball valve was kind of "Rube Goldberg" compared with having a proper thermostat to regulate engine temperature, but I'm re-evaluating that opinion.

[hanleyclifford]

Your point about the mess of winterization is well made. However, I intend to convert to FWC at some point, and would no longer need to remove the t-stat.

I always thought that the ball valve was kind of "Rube Goldberg" compared with having a proper thermostat to regulate engine temperature, but I'm re-evaluating that opinion.

The by pass valve is, in effect, a thermostat - utilizing human brain and dexterity as opposed to spring and lump of metal.

[Ajax]

If running with no thermostat, do you want the little check valve in conjunction with the ball valve, or just the ball valve by itself?

[joe_db]

You don't need both. The check valve is used as a fixed restriction and the valve is a variable restriction.

If running with no thermostat, do you want the little check valve in conjunction with the ball valve, or just the ball valve by itself?

[hanleyclifford]

If running with no thermostat, do you want the little check valve in conjunction with the ball valve, or just the ball valve by itself?

I do not use a check valve, just the by pass (FWC).

[hanleyclifford]

You don't need both. The check valve is used as a fixed restriction and the valve is a variable restriction.

And restrictions are the enemies of a cooling system, especially RWC systems.

[joe_db]

Sort of. The more you restrict the bypass the more cooling water flows through the engine instead of around it. When my old old engine would overheat I would clamp visegrips on the bypass hose and drop the engine temperature about 40 degrees

And restrictions are the enemies of a cooling system, especially RWC systems.

[hanleyclifford]

Sort of. The more you restrict the bypass the more cooling water flows through the engine instead of around it. When my old old engine would overheat I would clamp visegrips on the bypass hose and drop the engine temperature about 40 degrees

I do indulge in a little restriction inasmuch as I use 1/2" hose in the by pass loop and 5/8" hose in the main loop but since I use a 3 way (diverter) valve there is no issue of preferential flow. RWC engines with Dole thermostats are the most at risk for blockages but the later thermostats are not much better due to the reliance on a seal in a cast iron housing.

[JOHN COOKSON]

Reserve Cooling Capacity

I always thought that the ball valve was kind of "Rube Goldberg" compared with having a proper thermostat to regulate engine temperature, but I'm re-evaluating that opinion.

A good thing to have.
If the engine runs at the desired temp with the bypass valve wide open and if there is ever a problem with the cooling, closing the bypass may allow you to carry on under reduced power until there is time for diagnosis and repair. This is why I think a valve on the bypass is a good idea even in a "normal" running engine. It gives you positive control.
Clamping the bypass hose is a more crude method but would have the same effect.

TRUE GRIT