# Hirth 35HF Jet A 2-stroke, no oil mixing needed

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#### 12notes

##### Well-Known Member
Log Member
I stumbled across this engine recently but can't find any more info or if it's available to any organization too small to have it's own military:

It's a 2 stroke, 60 Hp, 79 lb (wet), 2 cylinder engine that runs on kerosene based fuels (Jet A) and doesn't need oil mixed into the fuel. My main objection to 2 stroke engines is the need to mix the oil with the fuel. This seems to solve that problem, it lighter than the 1/2 VW I currently have while being a lot more powerful. Apparently there was an earlier version called the 3503 HF, and I've also seen reference to the Hirth S1204 HF, which is based on the F23, and has 45hp and weighs around 50 lbs.

I was wondering if anyone has seen one, has any experience with one, or knows what they cost. Ideally, the S1204HF would work for my application if it can be found and it's not extremely expensive. 35HF would be overkill power-wise, but still fit.

Other than a potential whopper of a price, is there some downside I'm not seeing here?

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#### Hot Wings

##### Grumpy Cynic
HBA Supporter
Log Member
is there some downside I'm not seeing here?
Yes.
At only 79 pounds it will make all the work I have, and will do, to convert an industrial engine for my Quickie wasted time.
I suspect the price will be well into the 5 figures range so I'll just keep plugging along.............

#### 12notes

##### Well-Known Member
The similar gasoline version, the Hirth 3503 with fuel injection, electric start, and gearbox is $12,500, the 35 HF is probably more than that. The S1204 has a chance of being under$10K.