Multifuel engine intercooler - Steel Soldiers::Military Vehicles Supersite

cranetruck · 03-12-2006, 14:45

Installed two more temperature probes today to measure the effect of the water cooled intake manifold.
Drilled a 1/16 inch dia hole at the cylinder #5 intake (see image) and also a 1/16 inch dia hole in the intake manifold adapter.
Two thermocouple bead type probes were installed.
I also installed a temporary pressure/vacuum gauge to monitor the air filter canister vacuum.

After warming the engine to about 175F and making preliminary measurements, I took the deuce on test drive.
On a long uphill run in 5th gear at 55 mph the engine temp was 185F, the pyro showed 1,100 F, the boost gauge 10-11 psi, the adapter temp 222F and the temp at #5 cylinder 210F. The cooled intake manifold acts as an itercooler here.

Love that friggin multi!

The vacuum was 2 inches of water at 2,000 rpm, it pegged the needle at 2,500 rpm (conditions as above). The gauge only goes to 2 inches.

cranetruck · 03-12-2006, 14:58

Mounted the DVM/thermometer on the air intake since the thermocouple wasn't long enough to reach the inside of the cab from the intake manifold adapter.

Recovry4x4 · 03-12-2006, 15:04

There is so much more to these engines that us commoners haven't discovered. Sure a bombed B series might outrun it but I really love my multifuelers! Great information Bjorn.

Djfreema · 03-12-2006, 15:10

That is some really great info! Once again, another successful experiment by Cranetruck! Now I will stop daydreaming of a big FMIC on my duece.

cranetruck · 03-12-2006, 15:38

The results are preliminary, but interesting never the less. The filter vacuum reading is inconclusive since the gauge pegged out at 2 inches of water. Incidentally, the air compressor is getting its air from the canister as well, but there was no indication on the gauge when it was loaded (sucking air).
The ambient was about 62F. Deuce as shown below.
The air temperature must be different for the individual cylinders since the paths from the intake manifold adapter vary in length. Number 3 cylinder must be getting hotter air than number 6 for example.

I drilled the holes knowing that some debris would fall on the inside of the manifold, but it's all aluminum and a test drilling on a spare manifold resulted in very little debris. The thermocouple probes are 1/16 inch dia and fit snuggly in the holes.

cranetruck · 03-12-2006, 16:59

Installed a vacuum gauge with a wider range to measure the vacuum in the filter canister. Made another test run.
With a pyro reading of 1,100F and a boost of 11 psi, the vacuum reading was 20 cm of water. That was the max I saw.
This is a new filter with about 1,000 miles on it (courtesy of Kenny Engle) and should provide a reference for you who may want a different filter cartridge.
BTW all the test runs today were made with 100% petro diesel.

Djfreema · 03-12-2006, 19:53

It would be interesting to see the filter canister vacuum readings with a K&N air filter and aslo the charge air temperature readings before and after a K&N filter.

mangus580 · 03-12-2006, 20:29

Great Info Bjorn!!! Glad you were able to do it. Now that leaves one question to ponder..... would an intercooler be of benefit? Is there any benefit to dropping that temperature even more?

rizzo · 03-12-2006, 20:36

how are you cooling the intake?

mangus580 · 03-12-2006, 20:43

cooling is happening by the antifreeze coolant that goes through the intake by design of the multifuel engine.