SVX Engine cooling "Again & Again" - Page 102

oab_au · #**1516** 04-07-2013, 05:47 PM

Quote:

Originally Posted by Dessertrunner

Just installed a new PWR radiator into my wifes car, the radiator have lower fin count then standard and a 44mm outlet instead of the standard. PWR made a mistake with the radiator so I had to remove and relocate the power steering cooler. Also remember that this car has the thermstate now mounted on the top pipe on the engine.
What was interesting is I had the AC unit off which means the fans don't run unless the radiator gets hot and the air temp was 25C. I wanted to get the fans to run on so I let the car idle for 20 minutes.
The fans never turned on, in the end I gave up and turn the car off, I figure there must be some other issue but I could remove the cap with out any problem, no back pressure.
On the old system that the SVX had for cooling this would never happen the fans would turn on after 5 minutes.

Tony

Yes I have had mine idling for quite a while without the fans starting, but I can't see it not building pressure, must be a leak somewhere.

Harvey.

Dessertrunner · #**1517** 04-07-2013, 10:43 PM

Hi Mr Harvey.
It did build up some pressure but not enough that you can take the cap off. Normally you have to use a rag and have big B- - -s to take it off.
Tony

neverLift · #**1518** 04-19-2013, 08:46 AM

Tony/Harvey, where would the best place be to mount a coolant temperature sensor for a gauge? Before the thermostat on the crossover pipe? On the LHS head since its usually hotter?

This sensor for the gauge is also tied to a peak alarm/warning light and buzzer, hence why I was thinking the LHS head. Do you use existing threads/remove a plug for the sensor?

cheers
-Evan

Dessertrunner · #**1519** 04-19-2013, 12:24 PM

Evan,
the hottest part is the left hand head, so remove the plug at the back and make a new one for the sensor to bolt in to. Thay head will get hot before anything else.
Tony

neverLift · #**1520** 04-19-2013, 12:47 PM

Sounds good, will do. At what temp would you recommend the alarm coming on, i.e. when to back off, 100*C?

And when we are saying LH, is that drivers LH or looking at the car from the front LH?

cheers
-Evan

Dessertrunner · #**1521** 04-19-2013, 11:38 PM

Drivers left hand,
temp set at about 105C you can see this temp for short periods.
Tony

Dessertrunner · #**1522** 06-22-2013, 05:01 AM

I have removed

shark_22 · #**1523** 06-22-2013, 07:32 AM

very nice job!

these engine like to go in high rpm the only restriction is the overheating at this rpm after a few minute.

so this top thermostat gonna help alot!

But when using these top thermostat the 50mm housing still necessary or it not gonna help?

SVXRide · #**1524** 06-22-2013, 12:16 PM

Tony,

Excellent approach! Looking forward to seeing the test results.

Cheers,
Bill

Dessertrunner · #**1525** 06-22-2013, 02:42 PM

Quote:

Originally Posted by shark_22

very nice job!

these engine like to go in high rpm the only restriction is the overheating at this rpm after a few minute.

so this top thermostat gonna help alot!

But when using these top thermostat the 50mm housing still necessary or it not gonna help?

What the 50mm housing does is move the revs at which cavitation occurs up higher. Standard car and thermostate postion it will occur at around 2,000rpm, its so bad th coolant will stop flowing. Increase the suction size and cavitation doesn't happen tillaround 5,000 and its only small enough that over time it builds up air.

Bazza, Steve Jones & Matt all found there was a build up of air over time at higher revs.

In conclusion YES you need the bigger suctions etc and also need to restrict the coolant quanitiy. The side benfit of the change is that at high revs it will be harder for the coolant to boil as there will be a localize hi pressure in the block. My guess it will be arond 30 40 psi.

Tony

Dessertrunner · #**1526** 06-22-2013, 07:55 PM

Okay top therme holder will be shipped to Shark_22 on Monday and he will run some tests on the race track at 6,000rpm. Aim will be to find what size outlet minizes or stops the air build up in our engines.
Tony

Huskymaniac · #**1527** 06-22-2013, 08:05 PM

Couldn't you just install a bypass line in the cooling system with a pressure relief valve inline? When inlet-vs-outlet pressure of the radiator gets too high, the valve opens and partially bypasses the radiator to semi-equalize the pressures. That would create a situation where there is a maximum coolant flow through the radiator equal to the bypass pressure divided by the flow resistance of the radiator. If this maximum flow is good enough to provide sufficient cooling, there shouldn't be a problem.

Tireiron · #**1528** 06-24-2013, 11:36 PM

So I finally got my car out for a ride and I put the thermostat in the upper pipe and gutted the OEM thermostat down to just a gasket. I am not running an enlarged pump inlet and radiator outlet yet (looks like it will need to be dealt with though soon). The car is fine idling and driving around town, but once I hit the highway after about a mile the coolant gauge is spiking up into the red. I stop and idle for a minute and the temp floats back down to comfortable. Now it is possible I still have an air bubble to work out, but it was puking coolant out the overflow bottle as everyone else has encountered. I'm going to attempt to work anymore air out of the system for now, but my next aim is to get an enlarged housing then blow a bunch of money on a PWR radiator with the enlarged outlet.

As far as I know the headgaskets should be fine (this is sicksubies motor which him and tom built). After everything cooled down it pulled the coolant back into the motor, and almost emptied the overflow bottle in the process. I've had headgaskets go in EJ25Ds multiple times and in my old EG33 so I know how they tend to act and this didn't seem to be that issue.

I may try and go back to the OEM setup temporarily until I can get the pump inlet and radiator then go back to the upper thermostat setup, unless people feel that there may have been a large air bubble that I have to work out and this should run fine with the smaller pump inlet and upper thermostat until I can get the enlarged setup. This is not being tracked for now, just want to be able to drive it some to finish tuning it.

-Jason

Dessertrunner · #**1529** 06-25-2013, 03:01 AM

Hi Jason,
Did you drill a hole in the top thermostat? If you don't the thermosate will not see the hot coolant.
Do you still have both bypass pipes connected to both sides of the engine going down to the water pump?
Any chance the top thermo could be the wrong way around.
What revs is the problem developing?

Have to say standard radiator won't stand the pain.
Tony

Tireiron · #**1530** 06-25-2013, 05:32 AM

The rest of the cooling system is OEM minus the line into the throttle body (throttle body is bypassed). I have two 1/8th inch holes in the thermostat and it is the correct direction. I'm thinking there may have still been an air bubble and will work on it some more this way for now and take it real easy until I am sure the air is gone. And in the meantime I will source a modified housing and a PWR with the 45mm outlet. I'm running a 6mt so I don't have to worry about transmission cooling in the radiator.

As for rpms I would have to say it was when I was staying above 3000 to 4000 for an extended period of time. I have a JDM 6mt so the revs on the highway are not that friendly as they were with the auto.

Thanks
Jason

Thankfully I have 3 wrx motors sitting in my basement to use for parts and can send out a housing from one of them. I still need the outlet on the PWR to be in the OEM location though because of clearance for my alternator under the motor.