Toyota 2F Engine for 30kW Natural Gas Generator – SAE Bell Housing & Power Output

[knightrider85]

Hi everyone,

First off, I just want to say that this forum has been a great help whenever I run into issues with my Toyota 2F engine. I really appreciate the knowledge shared here!

I’m currently working on a DIY project where I plan to build a 30kW natural gas generator using a Toyota 2F engine. To achieve this, I need to couple the engine with a Stamford-type alternator. Could anyone with experience rebuilding or modifying these engines guide me on which SAE-size bell housing will fit the 2F engine exactly?

Additionally, I plan to install an electronic governor to keep the RPM stable and a Deep Sea module to monitor overall engine parameters. Since the 2F was not originally designed for high RPMs, I’m curious—how much HP/kW can I realistically expect it to produce when running on natural gas at generator-friendly RPMs?

Any insights, suggestions, or past experiences would be greatly appreciated! Thanks in advance.

Looking forward to your advice.

 

[charliemeyer007]

I'd do a 3 phase unit at 1500/1800 rpm. 30kW is like 40 hp so the 2F ought to be up to the task even on back propane.

 

[knightrider85]

I'd do a 3 phase unit at 1500/1800 rpm. 30kW is like 40 hp so the 2F ought to be up to the task even on back propane.

Thanks for the reply, mate!

I’ve done quite a bit of research, and the Toyota 2F’s reputation for reliability and high-end torque at low RPMs definitely makes it a great choice for this project. I agree, it should be up to the task, even running on propane.

The alternator I have is a 3-phase unit, but I plan to reconfigure it to single-phase. However, I'm currently stuck with the bell housing issue.

I’ve attached a picture of the double-bearing alternator—I’ll need to be very precise with its alignment, especially because of the added load. Any suggestions for aligning it properly with the engine and ensuring it’s stable would be greatly appreciated!

Looking forward to hearing your thoughts.

 

[knightrider85]

 

[charliemeyer007]

I ran gasolene 10kW on down gennies for my signal rig in the Army. Days to weeks at a time 24/7. Only once I got to change one 10kw to 3 phase and cut our fuel consumption buy 1/2. I did get to do some work with diesel 15 and 45kW. I favor pulling the power off in 3 places rather than one - just for balance.

I would think you could get some sort of keyed rubber isolated power coupling to fit between your generator and a gutted transmission (hi gear in 3 and 4 sp is straight threw 1-1 I think). These units easily can accommodate 1 degree alignment error.

I have watched a lot of pakistan's youtube machining vids and some of those guys have awesome talent for repairs.

My steam engine design used a fly ball governor driven off the distributor shaft. Inverted aluminium 4 cylinder Vega engine with the cam converted to make it a two stroke, injecting high pressure steam in the spark plug hole.

 

[knightrider85]

I ran gasolene 10kW on down gennies for my signal rig in the Army. Days to weeks at a time 24/7. Only once I got to change one 10kw to 3 phase and cut our fuel consumption buy 1/2. I did get to do some work with diesel 15 and 45kW. I favor pulling the power off in 3 places rather than one - just for balance.

I would think you could get some sort of keyed rubber isolated power coupling to fit between your generator and a gutted transmission (hi gear in 3 and 4 sp is straight threw 1-1 I think). These units easily can accommodate 1 degree alignment error.

I have watched a lot of pakistan's youtube machining vids and some of those guys have awesome talent for repairs.

My steam engine design used a fly ball governor driven off the distributor shaft. Inverted aluminium 4 cylinder Vega engine with the cam converted to make it a two stroke, injecting high pressure steam in the spark plug hole.

You're absolutely right about three-phase power—that's one of the reasons I got this alternator in a 3-phase configuration. Initially, someone told me that since it’s for residential backup, the phases wouldn't be properly load-balanced, but after hearing your experience, I don’t think it should be an issue.

Regarding the rubber-isolated coupling, I came across the Lovejoy coupling, which has a rubber insert between the teeth of the coupling—one side connects to the alternator, and the other to the engine. But that's not exactly what I’m looking for. I’d like a coupling setup similar to how Cummins original gensets are coupled, which is why I was asking earlier about the SAE flywheel housing fitting.

And yeah, you're spot on about Pakistani machinists—there’s definitely some incredible talent here, but unfortunately, skilled people like that are rare. I found one guy in southern Pakistan who has built hundreds of gensets using Toyota, Daihatsu, Mazda, and other engines. The best part? His canopy designs match Japanese models like Nippon and Denso! I’ll share his YouTube channel here:
Azeem Ahmed Generators

The only problem for me is he’s too far away, and sending all my parts across the country doesn’t make sense.

By the way, your steam engine project sounds absolutely insane! I’d love to hear more about how you converted that Vega engine into a two-stroke steam setup—that’s some next-level engineering.

Looking forward to your thoughts!

 

[knightrider85]

thats wat im looking for

 

[knightrider85]

Another thing I plan to do is increase the weight of the flywheel to improve rotational inertia. This should help compensate for the torque required when starting heavy appliances, preventing the engine from bogging down under sudden load spikes.

 

[knightrider85]

this is one his gensets its toyota 3s 2000cc straight six coupled me mc alte uk alternator, runnning on natural gas

 

[cruisermatt]

The closest thing you will find that will
bolt to a 2F is a 3-speed bellhousing. They have the same transmission pattern as GM.
The 3-speed/1F flywheel is substantially heavier as well and will bolt to 2F.

 

[Malleus]

^this
...beat me to it!

 

[charliemeyer007]

Engine mount 33.34. Then pump adapter which would be you genny head.

 

[knightrider85]

I need to determine the correct bell housing pattern to match it with an available SAE flange size (#2, #3, #4, or #5). From my research, SAE #3 or #4 seem to be the most common for medium-sized industrial engines, but I’m unsure which one would be the best fit.

Has anyone here worked with a similar setup or knows the exact SAE flange size that would match the Toyota 2F? Any guidance or recommendations would be greatly appreciated!

 

[POPO AGIE]

I'd do a 3 phase unit at 1500/1800 rpm. 30kW is like 40 hp so the 2F ought to be up to the task even on back propane.

To generate at 1500/1800 rpm the generator would have to be a 4 pole generator. 1500 rpm would have 50hz output and 1800 would have 60hz out put.

 

[charliemeyer007]

No clue what power cycle they use in Pakistan. 50 or 60 hZ and 120/240

 

[POPO AGIE]

I have never worked in Pakistan. I work for GE and have been working on turbines and generators for 32 years.
2 pole generators run at 3000 rpms for 50hz and 3600 rpm for 60hz
4 pole generators run at 1500 rpm for 50hz and 1800 rpm for 60hz

regardless of what part of the world and Europe and Asia are usually 50hz and North America are 60hz but Texas used to be 50hz and are still on there own grid.

 

[knightrider85]

ur right about it we have 50 hz which is 1500 rpm