SVX Engine cooling "Again & Again" - Page 8

SilverSpear · #**106** 09-27-2009, 04:49 AM

Tony, excellent job so far. Concerning the flow meter, what is your budget in US$ for that?

The tank method might be useful... to a certain extent. As you said getting approx numbers is better than getting nothing.

As for the coolant pipe clearance, do you think it will clear a stock manifold?

Dessertrunner · #**107** 09-27-2009, 05:52 AM

Budget a couple of $100. This manifold is the same hight as the standard.
Tony

TomsSVX · #**108** 09-27-2009, 10:24 AM

Quote:

Originally Posted by Myxalplyx

Just read this whole post! Lots of information. Very informative and technical. Since I'm the anti-technical.....here it goes.

Seems most people have been focusing solely on coolant flow, with the assumption that the left bank is flowing less and causes the car to overheat at sustained high rpm. Makes sense!...

Have we broadened our view to look at other factors that may come into play, which could cause the left bank to heat up? Here's a bone I'll toss out. The side that the left bank of coolant is supposed to cool. What cylinders is it cooling? Is it 1-3-5? Have we considered whether these cylinders are getting the proper amount of fueling from the injectors? If say...injector #1, #3 or the combination is not putting out the proper amount of fuel (or too much), could this simulate the same overheating of coolant that is being experienced?

Just throwing this out there since the cleaning of my Subaru's injectors (Old school and new) always resulted in #1 and/or #3 being worse than the rest, until I had them professionally cleaned. Increasing the coolant flow of the left bank may be like taking more headache medicine for the headache instead of removing the cause of the headache. Could only be prolonging the inevitable.

If this is far fetched, besides coolant flow, try to examine what else could simulate heating up of the coolant flow of the left bank, something other than just the flow.

I'll crawl back into my reading/lurk state and continue to learn now. L8Rs...

If indeed this were the case, it could be easily seen that an engine was not burning as well on the LH bank of the engine as it were on the RH. Unfortunately this is not the case and some are running SAEM which can and will compensate for said issues. The reality of the inejctors being dirtier is that they are first in line of the fueling system. Naturally anything moving past the filter will end up.... in the LH side injectors

Tom

SilverSpear · #**109** 09-27-2009, 12:42 PM

Quote:

Originally Posted by Dessertrunner

Budget a couple of $100. This manifold is the same hight as the standard.
Tony

Oh ok. I thought it is lifted because of the individual throttles.

This picture surely shows that we have a lot of space to do a Y system into the rad, just in case.

As for the flow meter, I am searching and sending emails to potential suppliers. Since it is Sunday, I guess we should expect something by tomorrow... our time

Dessertrunner · #**110** 09-28-2009, 07:19 PM

My friend with the buggy has tried changing the ECU from a Motec to EMS in an effort to solve the cooling problem as he beleived that the timing was out but it didn't solve the heating problem. I think he is at a point were he will pull the engine out and change to a different type. There is nothing he can do to keep it cool and now he is about to give up on the SVX engines.
Tony

dynomatt · #**111** 09-28-2009, 07:20 PM

You and I should make an offer on his engines...his current price is a bit high though.

M

oab_au · #**112** 09-29-2009, 06:03 PM

Quote:

Originally Posted by Dessertrunner

My friend with the buggy has tried changing the ECU from a Motec to EMS in an effort to solve the cooling problem as he beleived that the timing was out but it didn't solve the heating problem. I think he is at a point were he will pull the engine out and change to a different type. There is nothing he can do to keep it cool and now he is about to give up on the SVX engines.
Tony

I reckon we should take up a collection and buy you a Fuggan camera.

What has he done to the cooling system on the engine.?
What pump, and flow rate does it have?
What was the modification that he did to the outlet piping?
What is the radiator that it has.?
What rev range does it run?

Harvey.

Trevor · #**113** 09-29-2009, 08:03 PM

Quote:

Originally Posted by oab_au

I reckon we should take up a collection and buy you a Fuggan camera.

What has he done to the cooling system on the engine.?
What pump, and flow rate does it have?
What was the modification that he did to the outlet piping?
What is the radiator that it has.?
What rev range does it run?

Harvey.

Harvey,

Just in case criticism hits the fan, for what it is worth, I will back you on this one. I am as you are, fully aware that it is easier to advise than do, but it is becoming obvious that the train has never been on track.

The thread clearly shows a lack of any sort of logical approach in curing the problem. Basic rules covering testing have not been carried out. So far there is nothing but a confused set of trials, often two at a time. No proper conclusions have been established from work to date. Incoherent fiddling is not science.

What stands out is that the cheap and simplest options, have not been tested. Even if not a complete success, these could prove valuable in providing definitive evidence and move things forward.

There has been talk of flow testing. As I see it, this will only be of value if a figure for right and left sections can be established. From a mechanical slant, this would appear a very difficult proposition. The actual information required relates only to, --- is the flow to high or too low, on one side only, or throughout. This can be established by testing rather than measuring.

First up, blank off the heater circuit at the pump, remove the thermostat, i.e. for increased flow. Note the results before and after. A means of measuring accurately any change in temperature will be valuable. However again, actual figures are not that important.

As always, sticking neck out, Trevor.

Dessertrunner · #**114** 09-29-2009, 09:27 PM

I understand were you guys are coming from but I am the only guy that has a method to measure the return water temp and with in 3 day able to measure the head tempreture on each bank as well as return coolent from the bottom of the radiator.
As regards the buggy we have a race track on Steve farm and we measure how far the buggy gets before overheating. At this time I have been pushing him to measure return coolent temp but only now has he agreed that it might be an issue.
What we do know from trials we have done todate.
- Take out the thermstate as it overheats to soon otherwise.
- Overheating occur from about 5,000 rpm up. Below this it isn't a problem.
- If we are using a standard cross pipe ontop of the engine we have to return coolent to the pump through the heater pipe. This suggested the top pipe was a problem.
- The orignal radiator was over 3 times bigger then ours then it was changed to a multipass unit. This change improved to distance before overheating.
- We have tried a Craig water pump with the existing turbine removed and it was no good at all.
- Of the current pump options the orginal was best.
- Its not the ECU as we have tried two types, but both are having problems reading the cam timing at 6,000 rpm with the result that the engine is breaking up at high revs.

What we don't know but will is how well the airflow and radiator are getting rid of the heat generated before returning to the engine.

If I have forgot anything ask.

What I will be doing hopfully this week end :-
Fit dual temps to the heads.
Drive down the road at 110kph on a straight flat road for 100k measure outside tempreture.
Drive for 15 minutes in 6th then measure the temps on the three guages.
Repeat in 5th, 4th and 3rd while still driving at 110kph.

Graph the results, and I am guessing that as revs go up the left bank has a harder time getting flow due to the pressure restriction. If that is confirmed I will then change the top pipe over to the moded one (i have two of them) and re conduct the trail at the same outside air tempreture.

This is long winded but I am getting somwhere, I spent two much on my race engine to assume that it won't overheat so I intend to stay on the issue till it is solved. Have a great day guys and I hope you are all healthy and well.
Tony

TomsSVX · #**115** 09-29-2009, 09:33 PM

sounds like a solid plan. let us know how it goes

Tom

Boxersix · #**116** 09-29-2009, 10:14 PM

May I jump in here and just add some food for though......

-Loss coefficients of the coolant system in case?

-LC's of the pump diffuser/case coolant inlets?

-Relieve the case of micro bubbles at bores and vent to swirl pot(highly likely due to case passage design, compare 30/30r and porsche castings to EG casting

)? Have had some similar issues of this manner with some engine swaps(other chassis) where normal engine position is askew, causing localized collection of micro bubbles and ultimately reduce flow in specific jacket areas. Purging the case to a swirl pot eliminated the sitiuation in all instances. 4an(1/8th NPT tap) sufficed. Not completely sure of EG33 case thickness @ the bores, may require welding on a bunk prior to drilling.

Did not have this issue with the EG33 in the 96X2 prototype chassis, but then again the entire ME-RWD drivetrain in that car sat at about a 15 degree cant(motor low).

Quote:

Originally Posted by SilverSpear

This picture surely shows that we have a lot of space to do a Y system into the rad, just in case.

Take into account that and equalized "y-pipe" collector off the heads in place of the OE crossover will not yield a balanced left/right system as the flow path of the coolant inside the case halves from the coolant inlet(pump) is not balanced. If you were talking about some other setup for the "y pipe" then disregard this response

Carry on with normal discussion

oab_au · #**117** 09-29-2009, 11:29 PM

Quote:

Originally Posted by Dessertrunner

-
If we are using a standard cross pipe ontop of the engine we have to return coolent to the pump through the heater pipe. This suggested the top pipe was a problem.
- Its not the ECU as we have tried two types, but both are having problems reading the cam timing at 6,000 rpm with the result that the engine is breaking up at high revs.

Tony

Tony I take it that it is still running the standard crossover pipe?
Or is it modded with the swollen middle?
Or is it modded where they join on the right bank?

The heater will always pass water, I would not say it shows a problem. As one end is to the top pipe, the other is to the inlet side of the pump. Then you have the Bypass pipe that does the same thing from the other end of the cross-over pipe.

These types of sensors are not good for high speed operation, because of the reluctance of the unit, they can end up with a constant voltage, that can't be read. Thats why they have changed to the Hall Effect sensor for crank pick-ups, a more reliable signal at speed.

Harvey.

Dessertrunner · #**118** 09-30-2009, 12:00 AM

Harvey we are running the swollen cross over pipe now, when you say the hall effect type are better what cars use them and were would I get one. I was thinking of getting a sensor from a Porsche as you would think it could handle it. I think Tom made the point that the one on the crank is working at 12 times per rev and still reading okay but the cam is only read 1 time every 2 revs. Or have I got the bull by the tail instead of the horns?
Tony

SilverSpear · #**119** 09-30-2009, 01:35 AM

Tony, I have contacted two companies for you, I dunno if their products are applicable to car engines, pls check them out:

Liquid Controls
Pathfinder Instruments

I am still waiting for their replies

Trevor · #**120** 09-30-2009, 03:54 AM

Quote:

Originally Posted by Boxersix

Take into account that and equalized "y-pipe" collector off the heads in place of the OE crossover will not yield a balanced left/right system as the flow path of the coolant inside the case halves from the coolant inlet(pump) is not balanced. If you were talking about some other setup for the "y pipe" then disregard this response

Carry on with normal discussion

This is exactly correct. Difference in the flow resistance, relative to each side of the dual cooling path, will be the deciding factor, in spite of both outlets flowing equal and free. Correction must be achieved elsewhere.

Bubbles/air/turbulence as suggested, constitutes a very likely problem worthy of attention.