SVX Engine cooling "Again & Again"

[Trevor]

Those who are unable to read accurately; interpret adult language or comprehend same; think that I have nothing to offer; regard me as a pretentious and or hate my guts; please ignore this post and rattle your dags.

Kia ora Joe,

You advise --- “I'm finding the answers here interesting from a technical point of view.” Nothing has been proven, therefore you also wisely advise --- “We need to have another owner do the [clearly defined] modification in a car showing heating problems, then Tony's great work will be proven by peer emulation.”
(Better watch it Joe, your English is becoming rather haughty.)

I intended to provoke further thought, rather than be controversial. Everyone please, --- replies should be exactly confined to the questions specified, and should not deviate towards external whys and wherefores, or cover what is imagined is inferred, or might lie between lines.

First, --- it is important to take into account that large pumps of the irrigation variety, draw liquid via a port at the centre of the impeller and discharge off the side of the impeller. Whereas the small SVX pump is of a entirely different design and draws coolant via an offset port under the impeller, and discharges outwards from the impeller.

This means that the SVX arrangement requires specially designed and shaped inlet and outlet ports in order to direct the flow. The inlet passage within the pump cover, incorporates a thermostat, and the cover forms part of a chamber from which fluid enters the pump volute or diffuser, via a specially shaped final delivery port.

The outlet involves a specially shaped indentation in the block, and the cover, pump body and block mated together, comprise the complete pump assembly.

The interior port which delivers fluid via the pump volute or diffuser to the rotating impeller, comprises the last point of resistance/restriction within the cooling circuit.

Therefore within the area of the pump, the radiator outlet and pipe is the first point of resistance and has least resistance; the pump cover the second; the inner port the last; and importantly this has maximum resistance.

In the event that it is a proven fact, why does altering the radiator outlet pipe have an effect on cooling?

In the event that it is a proven fact, why does removing the thermostat and increasing the port within the cap/cover have an effect on cooling?

Could it be that altering the designed shape of the cover reduces the efficiency of the pump?

It is interesting that in many instances involving other cars, removal of the complete thermostat in the hope of improving cooling, has had the reverse effect. But removing only the inner valve portion, has proven effective. This would indicate that removing the body of the thermostat has upset the as designed, intake to the pump and has reduced pump performance.

I leave the cat among the pigeons.

[svxistentialist]

Originally Posted by Trevor

Kia ora Joe,

You advise --- “I'm finding the answers here interesting from a technical point of view.” Nothing has been proven, therefore you also wisely advise --- “We need to have another owner do the [clearly defined] modification in a car showing heating problems, then Tony's great work will be proven by peer emulation.”
(Better watch it Joe, your English is becoming rather haughty.)

I'm sorry Trev old boy, it's possibly caused by the sort of gits I'm conversing with.

Originally Posted by Trevor

It is interesting that in many instances involving other cars, removal of the complete thermostat in the hope of improving cooling, has had the reverse effect. But removing only the inner valve portion, has proven effective. This would indicate that removing the body of the thermostat has upset the as designed, intake to the pump and has reduced pump performance.

I leave the cat among the pigeons.

That's an interesting hypothesis and not without its possibilities. If true it might indicate that the rate of flow of the coolant fluid in Tony's modification is slower than that with the unmodified rad outlet. It [coolant rate of flow] could even perhaps be shown to be slowed down simply by removal of the thermostat if your housing inefficiency theory holds water. Pun intended.

This could be proven by a before and after flow-meter test.

And we wouldn't even have to ask Harvey to do it!!

Joe

[oab_au]

Originally Posted by Cam

copied from wikipedia:

"From about the 1980s, new designs of smaller petrol (gasoline) engines also displayed cavitation phenomenon. One answer to the need for smaller and lighter engines was a smaller coolant volume and a correspondingly higher coolant velocity. This gave rise to rapid changes in flow velocity and therefore rapid changes of static pressure in areas of high heat transfer. Where resulting vapour bubbles collapsed against a surface, they had the effect of first disrupting protective oxide layers (of cast aluminum materials) and then repeatedly damaging the newly formed surface, preventing the action of some types of corrosion inhibitor (such as silicate based inhibitors). A final problem was the effect that increased material temperature had on the relative electrochemical reactivity of the base metal and its alloying constituents. The result was deep pits that could form and penetrate the engine head in a matter of hours when the engine was running at high load and high speed. These effects could largely be avoided by the use of organic corrosion inhibitors or (preferably) by designing the engine head in such a way as to avoid certain cavitation inducing conditions"


From what it says about cavitation on Wikipedia (the above is only an excerpt) then we should have some damage in the cooling paths of the engine, or on the impeller. Does anyone happen to have a means of checking for distortions in the metal (ultrasonic testing...I am not sure what you could check it with w/o visiting a bandsaw).

It says there would be pitting, or bits of material removed in a way that would make the aluminum appear "spongy". Or like flashing, i suppose...:confused:

From my post #279.

Pump cavitation is a fact of engineering, it will happen with a standard engine. If the thermostat is partly closed it will restrict the inlet to the pump, and, at speed, it will cavate. If the impeller speed is high it will pull the molecules of water apart to form bubbles of void.
These are bubbles of a very low pressure, so the water around the bubble will instantly boil due to the pressure drop. It is not hard to tell if this is the problem as when these voids explode into boiling, they will create small pock marks around the aluminum casing, very much like detonation marks around the edges of a piston.
Having said that, I don't think the cavitation will stop the pump from pumping, in our case. Any modifications that you do the the impeller will reduce it's effectiveness at normal speeds. It is a trade off.

Harvey.

[Cam]

Since I have my engine in pieces right now, and have experienced A LOT OF OVERHEATING, I took the time to look at my engine last night. Also my water pump. There is flashing all over from where it was cast in the factory.

However, the areas where the impeller was milled out and all the parts that were not cast aluminum had no pitting, or spongey appearance. I can post pictures for all to see if you would like.

There is a drawback, however. My car had a blown head gasket, so there is no guarantee that my car was overheating from cavitation. I would actually think that it was not likely. If bubbles were to come in through the blown gasket though, the same damage should be present.

Like I said, if anyone wants to look at pictures for comparison/analysis then let me know, otherwise I will leave you all to figuring this out on your own as I have no expertise in cooling matters.

Good luck to all

[Trevor]

Originally Posted by svxistentialist

I'm sorry Trev old boy, it's possibly caused by the sort of gits I'm conversing with.

That's an interesting hypothesis and not without its possibilities. If true it might indicate that the rate of flow of the coolant fluid in Tony's modification is slower than that with the unmodified rad outlet. It [coolant rate of flow] could even perhaps be shown to be slowed down simply by removal of the thermostat if your housing inefficiency theory holds water. Pun intended.

This could be proven by a before and after flow-meter test.

And we wouldn't even have to ask Harvey to do it!!

Joe

Joe,

Your English is excellent, please do not drop the standard to that ruling here.

Harvey already owes us an answer, i.e. how to test and prove his scheming, steaming pump theory.

Trevor.

[JONES OFF ROAD]

Who really cares about theories, or cavitation versus boiling!!!!
I had a racing engine that got hot (and boiled)!!!!
I made the thermostat housing mod and THAT fixed it!!!! (no thermostat, or restrictor)
I dont give two-hoots about what the coolant does as it circulates, or cavitates, or boils......because my temperature runs cool, and thats all that matters!!!

There are plenty of suggested mods at the moment, those who need to should be trying the one of their choice (not just thinking about what might happen).....but I would certainly suggest the thermo housing enlarged and no thermostat or restriction as the start point. (you will also need to block the bypass pipe between waterpump (thermo) housing and crossover pipe).
It would appear that this thread is more about 'who's smarter than who', rather than fixing the mechanical problem.
Please also remember that this issue should only relate to racing/modified engines, if your road going stock svx is overheating, these mods will not solve the problem, you have other issues!
Sorry for sounding so cranky, but I am......this problem is all but solved

[Dessertrunner]

Steve right on. The whole soulation has got lost in all this theory. Both your and my engine are running cool and we can't overheat them so we have done our bit. Time to move on to the next project and stop wasting time on theory.
Tony

[SilverSpear]

Steve and Tony, you are both right. You've done enough so far for yourselves and the community. Indeed time for you guys to move to the next project and let this debate be over.
I can understand that on your side of the world, the thermostat is not needed since it is too hot. Tony if you don't mind that the fellas in the US continue with it posting the results of the inline tat.

[Trevor]

Originally Posted by Dessertrunner

Steve right on. The whole soulation has got lost in all this theory. Both your and my engine are running cool and we can't overheat them so we have done our bit. Time to move on to the next project and stop wasting time on theory.
Tony

Tony,

This thread is now too involved to backtrack.

Before you move on. ----- For the benefit of all, will you please advise where and when you reported that the engine in your SVX engine is now running cool, exactly how you fixed your problem and how tests were carried out.

Only after providing this long awaited information, will you have done your bit.

[svxfiles]

OK, I'm late to the party, but
when my younger brother Mike Krynock was road racing Kawasaki 900s Ninja's
they used an aluminum flat block off plate with three 10mm holes drilled into it instead of the stock thermostat.
This allowed enough water flow through the water cooled head and upper block for a 120 or so HP engine.
It is also to be noted that the said engine has an engine oil cooler of substantial size specifically designed th help cool this 10,500-11,000 engine.
OT

[dynomatt]

Tony's summary

http://www.subaru-svx.net/forum/show...&postcount=862

and

http://www.subaru-svx.net/forum/show...&postcount=897

Can we all move on?

[Trevor]

Originally Posted by dynomatt

Tony's summary

http://www.subaru-svx.net/forum/show...&postcount=862

and

http://www.subaru-svx.net/forum/show...&postcount=897

Can we all move on?

The above constitute summaries of nothing more than progress. Nothing is confirmed regarding exactly how the problem was fixed and how tests were carried out.

Nothing has been achieved, nothing has been finalised. Many have spent a great deal of time on this thread. NO, I for one will "not move on" until facts are established and there has been a satisfactory conclusion.

[SilverSpear]

Originally Posted by Trevor

Tony,

This thread is now too involved to backtrack.

Before you move on. ----- For the benefit of all, will you please advise where and when you reported that the engine in your SVX engine is now running cool, exactly how you fixed your problem and how tests were carried out.

Only after providing this long awaited information, will you have done your bit.

Trevor, first of all you know how much I respect you as a knowledgeable person and a senior member, so please do not take my comments personally. Throughout the history of this thread or any other thread, I never attacked you or your statements and I do not intend to, ever. But why are you giving orders to Tony to explain how his engine is running cooler? If I publicly state that I have done mod X and it increased the power of my engine by 10%, am I obliged to explain how?

I have done the copper intake mod before and I placed the cone filter in the wheel well and I fabbed a new bumper with a hatch to that filter. I realized that this is one of the best power mod I have ever done on the SVX at a time NO ONE agreed with me. They started telling me that copper will not have any effect in cooling the air sucked by the filter/engine and it will cause turbulence in the wheel well area and the engine will not suck air efficiently... you know what? I DON'T CARE! I am happy with my mod and I shared it over here and it is up to anyone who cares to follow my path, but no one obliges me to go to a dyno for example to prove my theory...

Same thing happened to Myxalplyx when he came up with the Y pipe intake system, everybody was against him... be he carried on and it was adopted later on (Tomyx intake).

No one obliges Tony or any other member to prove the validity of his/their work around here. If we believe he solved the problem, then we follow his path, if not, then it is our business...

Respectfully,
Danny

[Trevor]

Originally Posted by SilverSpear

Trevor, first of all you know how much I respect you as a knowledgeable person and a senior member, so please do not take my comments personally. Throughout the history of this thread or any other thread, I never attacked you or your statements and I do not intend to, ever. But why are you giving orders to Tony to explain how his engine is running cooler? If I publicly state that I have done mod X and it increased the power of my engine by 10%, am I obliged to explain how?

I have done the copper intake mod before and I placed the cone filter in the wheel well and I fabbed a new bumper with a hatch to that filter. I realized that this is one of the best power mod I have ever done on the SVX at a time NO ONE agreed with me. They started telling me that copper will not have any effect in cooling the air sucked by the filter/engine and it will cause turbulence in the wheel well area and the engine will not suck air efficiently... you know what? I DON'T CARE! I am happy with my mod and I shared it over here and it is up to anyone who cares to follow my path, but no one obliges me to go to a dyno for example to prove my theory...

Same thing happened to Myxalplyx when he came up with the Y pipe intake system, everybody was against him... be he carried on and it was adopted later on (Tomyx intake).

No one obliges Tony or any other member to prove the validity of his/their work around here. If we believe he solved the problem, then we follow his path, if not, then it is our business...

Respectfully,
Danny

Kia ora Danny,

Unfortunately, in anticipation, you have predicted controversy, have read between the lines and jumped to a conclusion.

In no way am I “giving orders to Tony to explain how his engine is running cooler." Please read my post as it was intended to be read.

“For the benefit of all, will you please advise where and when you reported that the engine in your SVX engine is now running cool, exactly how you fixed your problem and how tests were carried out.”

I agree that Tony is not obliged to provide any further information, but I do believe that in the circumstances prevailing, it is reasonable that he should do so.

Sincerely, Trevor.

[SilverSpear]

Originally Posted by Trevor

Kia ora Danny,

Unfortunately, in anticipation, you have predicted controversy, have read between the lines and jumped to a conclusion.

In no way am I “giving orders to Tony to explain how his engine is running cooler." Please read my post as it was intended to be read.

“For the benefit of all, will you please advise where and when you reported that the engine in your SVX engine is now running cool, exactly how you fixed your problem and how tests were carried out.”

I agree that Tony is not obliged to provide any further information, but I do believe that in the circumstances prevailing, it is reasonable that he should do so.

Sincerely, Trevor.

Trevor, I was not talking about this sentence above.

Rather I meant this one...
"Only after providing this long awaited information, will you have done your bit."