Milwaukee Midget

[ggl205]

Reading this technical discussion for a proper cooling system has me wondering why my cooling system works. What I have on the Lakester comes from years of using something similar on road racing cars. One simple feature was to keep the swirl pot (header tank) higher than the cylinder head/radiators and drilling a .125" diameter hole in the perimeter of the thermostat, all to bleed off trapped air. In a road racing car, it was often difficult to position the swirl pot higher than cylinder head but much easier in the lakester (see images). Also, I use just a 7 pound pressure cap on the swirl pot. BTW, my radiator is contained in a five gallon water tank.

John

[Milwaukee Midget]

Hi, John -
Yours is nicely laid out, and yes, space is tough to determine until we get the engine placed, but there's room to locate items on the firewall.  We actually won't know how well it cools until we get it to Bonneville.  The dyno provides the water for testing, and it's a variable we need to anticipate.

Bob, the stock injectors are rated at 16.75 - shy of what we need, although yes, we could up the pressure to compensate.  That said, by the time I had the 8 injectors I have tested and cleaned to find the best 4, the cost is about the same to order up new ones, which is the plan.

Talked to Mel today - needs a few more dimensions to get the rods ordered.

Rex - the accusump arrived while I was out of town.  You should see the check in today's mail, if it hasn't already arrived.  Again, a thousand thank-yous!   

[fordboy628]

Reading this technical discussion for a proper cooling system has me wondering why my cooling system works. What I have on the Lakester comes from years of using something similar on road racing cars. One simple feature was to keep the swirl pot (header tank) higher than the cylinder head/radiators and drilling a .125" diameter hole in the perimeter of the thermostat, all to bleed off trapped air. In a road racing car, it was often difficult to position the swirl pot higher than cylinder head but much easier in the lakester (see images). Also, I use just a 7 pound pressure cap on the swirl pot. BTW, my radiator is contained in a five gallon water tank.

John

Hi John,

Well if the swirl pot and or expansion tank is higher than the cylinder head and radiator, then many potential problems are averted.   Any trapped air collects at the highest point in the system, SO . . . . . . .



Systems where the cylinder head is the highest point can work:

A/   With a complicated air purging sequence as the system is filled.    The problem with this is: that if a slight overheating condition is created and there is no effective coolant recovery, the head gets cooked.

B/   Use of a pressure bleed system.    The problem with this is:  it is complicated to plumb, and can be tricky to size bleed orifices.   BUT, coupled with a coolant recovery tank, slight over-heating is not an issue.   Heat exchangers can also be placed wherever, and it does not matter if the cylinder head is the highest point in the system.


As far as pressure caps are concerned:

1/   Less pressure can be used if the components exchange enough heat to keep the coolant temp under the boil temp.   Boil temp will vary based on coolant used and pressure applied and ambient temp, etc.

2/   If the system components are marginal, then more pressure may save your butt/engine on a hot day.   Again, based on coolant used and pressure applied and ambient temp, etc.

But this only works if your engine's water sealing can tolerate more pressure.    Cosworth BD's are typically sensitive to this.    The older Coopers Gasket BA0202 (as well as others) head gasket, made specifically for Cosworth, would usually leak from the packing in between the copper face and the steel base if the pressure was more than 7 psi.   A "Bars Leak" capsule could save your butt, until a new head gasket could be fitted.    I used to use a Fel-Pro "Print-o-seal" gasket to solve that problem.   Then Cosworth caught on and used Fel-pro for their gaskets.   I think most Cosworths now run Cometic gaskets.

3/   If the heat exchanger(s) is(are) too small in all environments, then you have no choice but to fit larger or more efficient heat exchanger(s) or better ducting or ??


Fordboy

[Stainless1]

Chris, 16.75 is a very small injector... I think 600s come with 26 lb injectors these days....
Well all you need to do is find bigger ones that fit you TB. 
Looking forward to seeing this iteration of the Midget on the salt 

[ggl205]

Fordboy:

We exclusively ran the three mile short course at WOS last year so didn't stress the cooling system much. In fact, we had 150 and 175 mph limits for licensing (two drivers) along with ride height and other suspension adjustments keeping us from going long course. All I had on the spare parts shelf was a well used, British made radiator from my old 1979 Lola T580. It pressure tested to 20 psi OK but was warned by the radiator guy not to push it over 7 pounds due to age and construction method used to build it. Given I will be moving my battery, extra room is available for a larger tank and radiator. I may have to beg Stainless to crack the tank and remove the old Lola radiator in favor of a new one.

John

[Milwaukee Midget]

Chris, 16.75 is a very small injector... I think 600s come with 26 lb injectors these days....

It's my thought that it's likely a duty cycle issue on smaller, high winding motorcycle engines.  We're looking at peak hp to come on at 8,500 rpm.  A 600 bike motor is likely spinning better than 12k, so to meet demand in the short window of intake valve opening, one might increase volume with respect to time?  A quasi-educated guess on my part . . .

[Rex Schimmer]

Chris,
Glad you got the Accusump, I have also received the check. Hope it helps you with your oiling system.

Chris, Mark and John (ggl205) I also happen to have a double pass radiator that measures approx 15x15x4 that is from a Porsche race car. I had planned on using it on my track roadster rebuild but decided that the present radiator that I fabricated should be fine. If you can use this radiator I can supply pictures and exact dimensions and I would need about $100 + shipping for it. I also have a Harrison heat exchanger approx 10x15x4 inches, single pass with -10 AN male fittings for the in and out. Same deal except I would need $50 + shipping for it.

Rex

[ggl205]

Chris,
Glad you got the Accusump, I have also received the check. Hope it helps you with your oiling system.

Chris, Mark and John (ggl205) I also happen to have a double pass radiator that measures approx 15x15x4 that is from a Porsche race car. I had planned on using it on my track roadster rebuild but decided that the present radiator that I fabricated should be fine. If you can use this radiator I can supply pictures and exact dimensions and I would need about $100 + shipping for it. I also have a Harrison heat exchanger approx 10x15x4 inches, single pass with -10 AN male fittings for the in and out. Same deal except I would need $50 + shipping for it.

Rex

Rex, as you can likely tell, I am a cooling system illiterate not knowing advantages and disadvantages of dual and single pass radiators. I think your 10X15X4 single pass rad will fit in my tank but the -10 AN inlet/outlet diameters seem a bit small. Could the radiator be modified to accept 1.250" diameter tubes? Also, how much pressure will this radiator reliably handle? I would like to increase my system pressure 7 psi to 20-25 psi if the radiator can take it.

John   

[Rex Schimmer]

John,
The Harrison cooler is a former oil cooler from some sort of military aircraft and I am certain that it would handle 25 psi operating pressure, the challenge is that the tanks are fairly small and it add a 1-1/4 alum tube would require that the end of the tube would need to be pressed into an oval and the end of the tanks would have to almost be completely removed so it would at best be a compromise. I really think that it should really be an oil cooler, looking at the -10 fitting the I.D. is about .48 inches and I could easily increase to .53 but the pressure drop at 40 gpm of water would be about 4-5 psi/connection plus at pressure drop of about 5 psi/foot for the hose. You could easily have 20+ psi of pressure drop in just the plumbing! Not a good application. You might consider buying a piece of alum core and then making the header tanks your self and then making the radiator exactly what you need. I have made several radiator this way. We (Duke and I) thought about a radiator in a tank for our little lakester but decided that just a water tank designed to take 25 psi would be a better choice. We happen to have a fair amount of space in the rear of the car and we made the tank round and with dome heads, works great, but of course we do run methanol which really cools the engine. If you decide to make a radiator let me know I have a place in Kingman, AZ that has really quality core material. If you are interested in a custom unit Duke and I could also build you one to your spec, but it would be more than $50!

Rex

[ggl205]

Thanks, Rex. I will be in touch. Whichever way I go, it would require some sort of custom built radiator.

John

[fordboy628]

And now, for the obligatory "Goat Explosion" . . . . . . .

In the world I live in, there exists a need for the rapid disassembly of an engine, or perhaps an engine "mock-up".     Usually the purpose of this disassembly is to perform a "post mortem" inspection of the assembly, thereby to discover and document the root cause of the failure.   Sometimes though, the need is just to check some additional dimensions, or perhaps to proceed to the next part of the engineering and fitting procedure.   Now mind you, the post mortem process should always be deliberate, thorough and unhurried, the better to learn of, and benefit from, any "mistakes".

However, the engineering design and mock-up process requires no such deliberation, the result of which is that any nearby flat surface collects the hastily dismembered bits.

Resulting in the work bench "goat explosion", thus seen below . . . . .



and also below:



Since the goal of the disassembly was two fold:
A/   Remove the crankshaft to prepare the mock-up assembly for welding up the "neutered" oil sump, and the requisite "re-assembly"





2/   And to have the crankshaft out and available for the checking of dimensions needed for billet connecting rod ordering.



More about the connecting rods in the next installment of:

Adventures on the Milwaukee Shore, Non Froedtert Heart Transplant, Season 4 . . . .



NotChristiaanBarnardboy

[fordboy628]

Just for anyone who is interested:

After a short learning period, I am officially in love with the ease of using Flickr to post photos.


Fordboy

[Milwaukee Midget]

More goat chow to come -

Stopped by C&S today - and CLINT was there!  That's Mel's kid - he started his own shop up in Menomonee Falls - good catching up with him.

Mel and I pulled down the Saenz order form and filled in some numbers.  He's faxing it off today - hopefully should have more number$ tomorrow.

Also called Lenny and Tom at T&T.  Lenny's handling the piston order - Tom's e-mailing me the EFI info.  I'm looking to have all of these orders placed before the groundhog shows his ugly puss this weekend.

[Stan Back]

Is "placed" akin to "filled"?

[Milwaukee Midget]

Is "placed" akin to "filled"?

In my experience, they are, at best, estranged relatives.