I bought a 7 hp Hatz diesel engine

[bigtoy]

I have always wanted a small diesel engine to play with. I found a 7 hp Hatz diesel on craigslist for $400. 00. It was pretty close to home, and new ones sell for $1800. 00+. It starts good, seems to run good. There is no way I am ever going to spend the money for a new one.



Is there anyone out there that knows or deals with these diesels? Thanks!



Here is a video of it: YouTube

 

[MChrist]

I'm sure you'll find good use for it. Only small diesels I have are the ones in our mini excavators. They are 8 hp 2 cylinder motors made by (I think) Isuzu.
Yours would be great for a log splitter. Run that threaded part to another muffler and split all day!

 

[Nyoest]

Man that thing has a bad knock at idle. No wonder they sold it cheap.

 

[bigtoy]

Yea, I agree, but I am not familiar with small diesels, but aren't diesels known for clatter? especially air cooled diesels. I believe the compression ratio is 21 to 1. I would think that would knock quite a bit compared to my 7 hp gas snowblower. That is why I idled the engine on the video for opinions. Thanks for watching

 

[Mikey-KE7LBB]

pretty cool! I'm thinking it'd fit nicely in a Go-Cart...

It just needs a turbo to make it go fast!!!

 

[tpuig]

That's pretty cool. What's the typical use for a small diesel engine like that? Pumps, etc?

 

[JJPage]

Need to mate that with a generator, would make a nice genset.

 

[mwilson]

I have been offered a 2 cylinder Yanmar Diesel from a scrapped T/K unit. I think it is 8 hp. That would give me the radiator, flywheel coupler, starter, alternator, etc. all in place.

I think that will become my household standby genset.

Kinda' thinking it would make me a nice winter project... ... .



Mike.

 

[bigtoy]

A genset is probably what it will become, who knows. I bet it would use alot less fuel than a comparable gas engine. I was told it was used as transfer pump for a huge excavation company.

 

[NIsaacs]

Thats a cool little diesel. When I was kid, a local rancher gave me a 1/2 hp. two cylinder maytag two stroke engine. It was off an old wood tub washing machine. Ours was more modern, it had a 1/2 hp Brigs. 4 stroke and metal tub:-laf I played with that little toy for years, I wish I still had it:{



Nick

 

[CKelley1]

i own several hatz diesel engines they hold up very well. they are used on our vibratory trench rollers for compaction. they are on about four different brands of rollers we get our parts from frank supply

 

[Bill Stockard]

I have been offered a 2 cylinder Yanmar Diesel from a scrapped T/K unit. I think it is 8 hp. That would give me the radiator, flywheel coupler, starter, alternator, etc. all in place.

I think that will become my household standby genset.

Kinda' thinking it would make me a nice winter project... ... .



Mike.

It won't make a very big standby gen set. Engine hp to kw output on small generators is usally 2hp=1kw. 8hp=4kw. Also, being it's only a 2-cylinder, and depending on the engine rpm, you may notice a flicker in the lights since it so long between power strokes. With a 2-pole alternator, the engine will have to turn 3600 or a 4-pole it will have to turn 1800 in order to deliver 60 cycles.



Bill

 

[DJW]

Regarding the knock in the engine, some years ago on a trip to the UK waiting for my friend a small car came out of a rented garage, he driver idled the car while closing the garage door, when he returned I said, "If that's a petrol (gas) engine you have an expensive noise", he smiled and said it was a diesel, when he drove off the engine sounded smooth and a lot quieter than when it idled, maybe the nature of some diesels, although it was several cylinders. I thought it was on its last legs, but car diesels are quite common in the UK, so probably he knew what he had and was not concerned of the idle noise.

 

[rscurtis]

I've never owned a Hatz, but have owned a Yanmar and Robin (Subaru) single cylinder diesel. The pronounced fuel knock at idle is very common. Unfortunately, the Robin is no longer sold in the US thanks to the Punishment Agency. I do have a testament to their durability and robust construction. I once sold a 3" pump to a cesspool contractor with the Robin DY 27 engine. He had it long enough to wear out the original impeller. One day, one of his guys dropped it into a cesspool. It damaged the air filter and set the rack at the starting fuel rate- much more than the engine normally runs on. One of his employees brought it in for repair claiming "it makes a lot of black smoke and the muffler turned orange". Sure enough, the exhaust was as clean as you'ld see on a new truck. I replaced the air filter and repaired the throttle linkage, and it was none the worse for wear. I still had a new 2" version in stock, and when running it, there was no difference between the two.

 

[Nyoest]

Man that thing has a bad knock at idle. No wonder they sold it cheap.

Just a joke. Neat engine, wish I had one.

 

[mwilson]

It won't make a very big standby gen set. Engine hp to kw output on small generators is usually 2hp=1kw. 8hp=4kw. Also, being it's only a 2-cylinder, and depending on the engine rpm, you may notice a flicker in the lights since it so long between power strokes. With a 2-pole alternator, the engine will have to turn 3600 or a 4-pole it will have to turn 1800 in order to deliver 60 cycles.



Bill

It would be replacing an 8hp Briggs, I hadn't checked the specifics yet. I appreciate the heads up and will check the 2-pole/4-pole issue out.



Anyone know right off the top of their head what a Briggs turns on the governor under load????



This 2-cylinder would be the same engine used on the Tri-Pac gen sets but they charge the truck using a standard belt driven alternator.



I will study the donor generator tomorrow in detail.



Mike.

 

[Bill Stockard]

It would be replacing an 8hp Briggs, I hadn't checked the specifics yet. I appreciate the heads up and will check the 2-pole/4-pole issue out.



Anyone know right off the top of their head what a Briggs turns on the governor under load????



This 2-cylinder would be the same engine used on the Tri-Pac gen sets but they charge the truck using a standard belt driven alternator.



I will study the donor generator tomorrow in detail.



Mike.

If the Briggs is on a gen set with a direct drive, it will be turning 3600-rpm. If it's on a belt drive, I have no idea... depends on the pulleys. The B&S won't have enough power (torque) and engine cooling would be a problem at 1800-rpm. If you run your Yanmar on a gen set with a belt drive, you can run it at about any speed you want by changing pulley sizes.



Bill

 

[mwilson]

I wonder what the governed speed of the Hatz will be?. .



Mike.

 

[guldam]

Renn Tolman is the guy who designed the boat I built. His last design is a hybrid of a Tolman Skiff upper part, and a Seabright skiff's bottom. He powered with a marinized Kubota Diesel.



Renn Tolman's Tolman - Seabright Skiff 2 - YouTube



Renn Tolman's Tolman - Seabright Skiff - YouTube



One day I want to build another boat, and power it with an inboard diesel.



GulDam

 

[bigtoy]

Thanks for all the replies! Fun to read. I believe it's max speed is 3600 rpm. I just checked the engine tag and I can't tell for sure it looks like a 6 and 4 were stamped in the same place. So it's either 3400 or 3600 rpm.