# New to me QT16 with power loss under load



## Linusb212 (Sep 18, 2016)

I found a very nice QT16 with mower deck and snow thrower. It has no rust and is about as nice as a 40+ year old unrestored tractor can be.

The only problem it seems to have is that under load such as going uphill the engine bogs and loses most of its power. 

I'm not quite sure where to start with diagnosing. Thinking I should just sell it to someone more capable but not sure. 

Does anyone have any suggestions on the power loss


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## RC Wells (Dec 26, 2008)

The engine should be an Onan BF-MS 2-cylinder opposed twin of 659 cc. Start with the carburetor.

The most likely cause of loss of power on an older machine that has been parked for a while is a clogged carburetor. The main and pilot jets become obstructed with debris from old fuel. As the engine requires more fuel from a load, the carburetor is unable to respond.

A broad statement is that the small tractor is an excellent product, and probably well worth cleaning or replacing the carburetor if all the other functions work well.


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## jhngardner367 (Apr 5, 2011)

Welcome to the forum!
That ONAN engine is touchy about the point gap,and spark plug gap/type .
Try setting the points at 0.020",and the spark plug should be a Champion h8,or modern equivalent(champion H8C),with a gap of 0.025" .
Once that's done,make sure the fuel is fresh,and also check for spark on both plugs.
Then, check the carb adjustments.


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## dozer966 (Dec 30, 2014)

I would start with air filter and fuel filter. Cheap and easy to replace . Also check spark on sparkplug and also cheap to replace. If no fix go to carburetor. The kiss system is usually the best.

Great looking machine I wouldn't get rid of it and it has direct PTO drive in front for the blower and not belt.

Good luck


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## Linusb212 (Sep 18, 2016)

Thanks guys! Thank you for the advice - it very much is a nice machine. I would like to get it running strong.


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## SnowmanPA (May 12, 2007)

*QT-16 Experience*

I had a QT-16 for many years and I loved that machine. Actually, I had FOUR. Two were nice running and two I had picked up for parts for little to nothing. 

I found that the Onan twin was a really nice motor with a good deal of power. But when I first bought mine, it too would lose power when it was getting warm. I found that the vacuum impulse-type fuel pump seemed to be the culprit. I replaced the vacuum fuel pump with a small "Mr Gasket" 12-volt electric fuel pump designed for small engines. It completely solved my power issues. I ran it that way for 3 years until the entire motor itself became so worn out that I replaced it with a 24-hp Honda.

The tractor itself...never had a problem with it. I put a 3-point hitch on it and I could pull a 5-foot york rake around my 1-acre yard with no trouble. I only grudgingly parted with it when I sold everything and moved out of state and back to the city.

Good luck with it.

Ted


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