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What are the advantages and disadvantages of putting a turbo on my little 332. Also Would I need an intercooler?
 

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Disadvantages: $$$ and labor.

Advantages: Looks & sounds "kewler", more power!

Your going to find you really don't need more power from that Yanmar. Traction will be your issue. My 14 hp Kohler in my 314 never ran out of power with a 49, a 54 blade or a 33 tiller. Lost traction, yes, but never stalled or bogged the engine.

Just my 2¢, Bob
 
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I can't answer that with any facts or experience, but I'm thinking a turbo basically puts more fuel into the engine. More fuel equals more heat. With that, I would surmise you'd need an intercooler.

Are you experiencing overheating problems now? If so, just the light on the dash or blowing out overflow tube. Could be a multitude of issues: bad sensor, bad water pump, clogged radiator, bad thermostat, bad radiator cap.

If your looking to install a turbo to cool your engine, I (personally) don't think it will help...with or without additional cooler. Bob
 

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If this is something you want to do, do it! If it doesn't work out for whatever reason, you can always take it all off. Go for it! Bob
 

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The advantage is a couple horsepower and lb ft torque under load at high rpm. The disadvantage,as stated is the time and money needed to put the turbo on will likely never be returned in work performed. I did this last winter and found I could push through a sidewalk plowing, that I couldn't without the turbo. What did that save me, about 30 seconds a run. I pulled the turbo this spring ,as it was getting a bit loose and was putting a bit of oil into the intake tube. (chinese turbo)
 

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The turbo will only put more air in the cylinder.
To take advantage of that available air, the injection pump would need to be recalibrated.
That recalibration would be determined by the pop off valve. The pop off valve limits the boost pressure at a certain level.

Just adding a turbo and not recalibrating the injection pump is a recipe for disaster. To much air, not enough fuel will multiply the heat in the cylinder many times.
That heat is what kills a diesel engine. It takes out the rings, scuffs cylinder walls, and melts pistons.
If you decide to add a turbo, get a pyrometer.
Put it in the exhaust manifold before the turbo.

Also, the recalibration of the injection pump is pretty much a wag, expect to do it at least twice.

Wag = wild ass guess.
Good luck.
 

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The advantage is a couple horsepower and lb ft torque under load at high rpm. The disadvantage,as stated is the time and money needed to put the turbo on will likely never be returned in work performed. I did this last winter and found I could push through a sidewalk plowing, that I couldn't without the turbo. What did that save me, about 30 seconds a run. I pulled the turbo this spring ,as it was getting a bit loose and was putting a bit of oil into the intake tube. (chinese turbo)
It sounds like heat did the damage.
Do these little diesels have oil coolers on them?
 

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Squirrel, these little chinese turbos are a journal bearing design. I ran a piro guage from the start. I never turned up the fuel or worked it hard/long enough to build excessive heat. I would also idle it down enough time before shutting it down. Heat was not the problem. As far as what you said about turning up the fuel to match the air,that may be sound advice for a gas engine,but these diesels are load-regulated. The more load you add,the more fuel the govener will add to maintain the set RPM. Diesels LOVE air! It is the addition of fuel that causes heat(and boost). My 332 would only build 2-3 lbs boost under heavy load,not nearly enough to engage the wastegate. I have been driving and working on my own turbo diesel trucks for adout 10 years and have learned a thing or two in that time. There is always more to learn ...I can rebuild this little turbo for under $100, it's just a matter of prioritys.
 

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I should cear up my "deisels love air" statement before it bites me in the butt. Deisels love COOL air. As you add boost and compress the air it gets hotter. I imagine this is what you were talking about as far as air causing dammage in a diesel engine. That point is well taken, but again, 2-3 lbs boost doesn't build much heat in the winter.
 

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You are correct Mr. Doug, the addition of fuel does cause heat.
But an increase of air in the cylinder will lean it out. That lean condition causes a lot more heat.

If your turbo only produced 2 or 3 psi boost, there was something wrong. Maybe wastegate, turbine or impeller not sized correctly.

All I know after 20 years is, you cant do 1 thing without doing the other. It just doesnt work.

The other variable that would need to be adjusted and set is the timing. A mechanical injection pump sets the timing.
Theres a lot more to it, than just installing a turbo.
 

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I should cear up my "deisels love air" statement before it bites me in the butt. Deisels love COOL air. As you add boost and compress the air it gets hotter. I imagine this is what you were talking about as far as air causing dammage in a diesel engine. That point is well taken, but again, 2-3 lbs boost doesn't build much heat in the winter.
No, I figured you knew that much.
I was referring to the addition of pressurized air into the cylinder without the additional fuel to balance the cylinder.
 

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"the addition of pressurized air into the cylinder without the additional fuel to balance the cylinder." ...will result in a cooler combustion, this in turn will reduce the speed of the turbo,this will reduce the amount of pressurized air into the cylinder. No?
 

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You're right Doug. If the load is really high you'd want to go rich, were it a gas motor (in order to reduce knock and cool the Piston). The extra air reduces the pumping loss, and you increase volumetric efficiency to above 100%. Since it's a diesel, you don't need to worry about knock obviously. The Diesel being more thermally efficient than the Otto cycle, you don't really need to worry about cooling by going rich. As you said, the EGT will likely be the limiting factor due to too much fuel. Always run your diesel lean :)

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If you have to much air and not enough fuel in the cylinder, it results in heat. The fuel cools the cylinder.
I've had many, very many injectors fail to put the required amount of fuel in a cylinder. Always the same end result. Bad rings, scuffed cylinder walls, melted piston, all from a lean condition.

Now an over fueled cylinder generally results in fuel in the oil. Usually will smoke black under load to. Usually you'll find a scuffed cylinder and bad oil rings on the cylinder. And a very clean piston.

A diesel is not a gas engine, the only common thing is there 4 stroke.
 

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Skwirl, I still don't get your point. Isn't the amount of boost a product of the amount of fuel introduced into a turbocharged engine? If you have no fuel,you have no boost. You cannot compare the failure in one cylinder to a complete engine assembly.
 

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Skwirl, I still don't get your point. Isn't the amount of boost a product of the amount of fuel introduced into a turbocharged engine? If you have no fuel,you have no boost. You cannot compare the failure in one cylinder to a complete engine assembly.
No, boost is not based on fuel.
Engine rpm is.
Boost is based on heat. Combustion chamber heat cause hot exhaust flows fast. That how a turbo works.
When a diesel is at idle, theres no boost.
What keeps it running?
 

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If a truck is giong down hill how can the engine RPM increase if there is no fuel. What keeps it from overheating,as air is the only thing going through the engine,and no fuel to cool the cylinder?
If boost is based onheat,which I do not dispute,why is there no boost at idle.
"When a diesel is at idle, theres no boost."
What keeps it running?" I suppose fuel and air keep it running. A small amount of them.
So what about load? Does load cause heat? What causes load. Will a properly sized turbo spool on an engine that has heat and load,but very low rpm ?

Would it be safe to say that enough load and enough rpm are required to produce boost.
 

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I believe you are right Doug. An NA diesel pumps the maximum air possible all the time, since there is no throttle. Mass air flow does not change. If you add a load, the governor will compensate by adding fuel in order to keep the same RPM on the Yanmar. Exhaust mass flow rate increases only with the amount of fuel added. Mass flow is a very big knob when talking exhaust energy. At full load, the engine will burn all of the available air in cylinder, or at least most of it.

For a boosted engine, the same applies. Only when you add load and subsequent heat, you will spin the turbo, which introduces even more air. Increasing air mass air flow. This allows you to add more fuel to burn and make more power. As you make more power, the total exhaust mass flow increases further.

The misconception is the heat of combustion. Diesel burns at the same temperature regardless of how much or how little is used. What changes is the mass flow. The higher the mass flow, the further the heat travels. What I mean by this:
The Piston, cylinder, valves, head (and coolant), and exhaust all absorb heat energy from the gas that flow through it. The higher the mass flow, the hotter everything gets. If you exceed the rate at which everything can reject the heat, you get in trouble.

With a gas engine, you restrict the amount of air, and soak the cylinder in fuel that absorbs a lot of that heat energy in the form of evaporative cooling. Some fuel does not get burned (running at 11:1 AFR for example). In a diesel, since it's always running excess air, you have no knob to turn that limits the fuel burned other than reducing the volume of fuel in cylinder. This is why too much fuel in a diesel can be bad.

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