Intercooler or "interheater" Cummins 5.9

[Skoolie BOBB]

I was looking at my engine a while back and it appears that the intercooler actually uses engine coolant in the intercooler. If this is the case, then the coolant that you use to HEAT the interior of the bus is the same as what is used to COOL the incoming air charge. Does that make sense?? If I understand intercoolers, it is to take the heat out of the incoming air so it will be more dense when it enters the combustion chamber. I've read articles about cold-air intakes for Japaneese cars and they substantially increase the power. Temperatures are relative. The air may be cooler than without the intercooler, but there still has to be some heat in it.

A solution??? So, I look on ebay and this guy has water pumps that are used on a Ford, F150 Lightning. I bought one. What I would like to do is by-pass the intercooler and send the coolant right back into the engine. Then, construct a totally separate cooling circuit for the intercooler. I'd put in a resevoir tank, a little radiator like what is found in a heater in a car and my pump. The only heat I would be dealing with is that picked up in the intercooler--not the engine itself. Cooler air, more power, more fun.

I do wonder if the engine would run lean with this modification. It is a '90 and it doesn't have a computer to monitor things. Any comments?

Herb in Utah
1990 Flatnose 'bird

 

[bdavis441]

sounds like a good idea, you just need to devise a setup to measure intake air temperature after the intercooler to verify effectiveness. I think you will find that a rather large system will be required due to the amount of heat produced by the turbo to be effective. I am curious how this will work. Keep us posted.

 

[Kirbystud]

The intercooler makes the air going into the engine the same temp. Yes when it's hot outside it is cooling the air going into the engine. But when it's cool outside it is also heating up the air going into the engine. So the engine can run more efficient all the time. No matter what the temp is outside. So I don't think it would help you any. But I like the way you think........

 

[bdavis441]

But when it's cool outside it is also heating up the air going into the engine.

The intake air is heated by the exhaust driven turbo. Ambient temperature is not the issue. The intercooler is never heating the air, it is always cooling the air down from the higher temperatures of the turbo.

 

[Skoolie BOBB]

The ambinet temperature will be the coolest the the incoming charge could be unless you did something like add a mist-sprayer. And, yes the heating of the air does come from the heat produced by the exhaust side of the turbo. It is the fact that coolant from the engine isn't all that "cool"--it has engine heat in it.

A guy stopped by our house and he had a Dodge Ram with the Cummins. This engine had a huge intercooler radiator that is in front of the regular radiator. I was surprised at it's size. It makes me do some rethinking about the size I will need. Brad mentioned above that it would be a good idea to measure the air temperature before and after. I had some of the same thoughts. I also was thinking about putting a gauge that measure the fuel/air ratio. They aren't all that expensive--a new engine is.

Herb in Utah

 

[Rick78EFI460]

First, you can't run a Diesel too lean, it just isn't in the equation. The more air you have , the more oxygen there is for combustion. There is no stociometric air/fuel mixture for a Diesel , a million parts air to a part of fuel is OK . Not enough air for the given fuel makes black smoke (soot) and poor economy. Every intake stroke you want every O2 molecule you can possibly have in that cylinder, then you add the amount of fuel you want to burn. This is why turbochargers are so effective on our Diesels.... very different than a gas motor that requires a specific mixture. Most of the temperature caused by the turbos is due to the act of compressing the air, not the exhaust temps as you would expect. Any time a gas (air) is compressed it creates heat, and compressed air can be very hot. This very hot air can cause a pre ignition event in the motor, which is very destructive. This is the whole reason for the intercooler, you want to bring the compressed air down to a reasonable temperature before you introduce it into the motor. The only guage you really need in your turbo'd Diesel that may not be there is a pyrometer to monitor the temperature of the exhaust gasses.

 

[Skoolie BOBB]

I honestly didn't know that the air/fuel ratio isn't all that important. Thanks. I have to say that I am surpised that the compression of the air makes that much heat. I am quite aware of the physics involved but surprised that just that small amount of increased pressure makes that much heat. Thanks Rick.

Herb in Utah