The Railspeeders Forum

What engines are available to replace an Onan.

What needs to happen to get it done, and are there parts available?

Can anyone comment on the success/problems with this type of installation, and how complicated it is.

Trackman

From what I've seen on the Les King/Dean Mark website, the Honda replacement engine is no longer available, but the B&S Vanguard is still available.

Dean Mark still has them listed on the website, along with the kit needed to mount it in place. Quoting the website :



What's wrong with your Onan that you need to replace it?

- Jonathan

Trackman-
That is quite a topic, you need to do a lot of reasearch before jumpng in as it's a one way decision. Your not going to take a conversion back out if you don't like it as good as the Onan, yor going to put up with it. A direct replacement means the replacement unit does everything as well as the original, so just know righ now that there is no such engine. There are happy conversion owners, and there are not so happy conversion owners. I've lost count how many times I've discussed gearing changes on those conversions, but never on an Onan powered car. I'd be for driving a conversion car before buying.

Jerry

The text on Dean Mark's page reads exactly like it did when that was Les King's page, including the comment about which engines were in stock. I would check availibility with Dean before making a decision.
Bill Delmar

FYI,

I'm not sure if this is a compatible motor or not, but Northern Tool lists a 23hp B&S motor :

http://www.northerntool.com/webapp/wcs/ ... 476_278476

- Jonathan

On a two speed car the comments I have heard are the V twins don't have the low end torque and lugging power compared to the Onans. Haven't actually seen the curves. Just Googled CCKB torque curve and got this ad from NARCOA site:

Fairmont transmission sprockets. If you have a Briggs or Honda conversion you know that the standard Fairmont sprocket ratios designed for Onan's are other than ideal and these engines are not exactly happy campers. They tend to lug at lower speeds and you need to be going too fast to even approach the optimum torque curve. I have a limited number of tapered bore, tapered key Fairmont transmission sprockets available. The 17 tooth seems to be ideal for touring at track speeds and the smaller ones (14,15, & 16) are best for narrow gauge cars and cars normally operated at low speeds or towing work trailers.

I have this posted on the general page. I am in the process of swaping engines out now.
Progress report. After busting one of my ONAN clutch hubs it was time to back up. After extensive conversations with Dean at Fredericksburg Shops a succesful solution has arrived. I am going to do Dean drawings of the assembly and a set of instructions along with photos. Actually it's going fairly well now, once we figured out what order it has to be assembled in. You see no instructions come with the Les King Kit. I'll keep you posted.
I picked up my engine from http://www.millcreeksawshop.com/. They have the supplier drop ship it from the warehouse, saving you shipping cost. Very nice people to work with and a fair price.
The engine you want is "Briggs & Stratton Vanguard V-Twin Horizontal Engine with Electric Start — 21 HP, 1in. x 2 1/4in. Shaft, Model# 385447-0075-E1". Acording to Briggs the 23 HP engine is to strong. By that they mean you will never make the engine work up to it's capacity. Briggs suggested the 21 HP so thats what I am going with. I still may have to change the sprocket out. Time will tell


Mike

I re powered my speeder with a 23 hp vanguard, and added a 60 amp Denso, external alternator. It has been a year, so far I like it.
Why did I "change" engines?
Onan was was worn. Plugs fouled often. Onan parts are expensive. 500.00 gets you a hatfull, and not a large hat. Local parts source is a difficult person, for me, to do business with.
I "geared down" on the advice of Dave Myers. 23T sprocket to a 21T
It seems to be the correct ratio for my needs. I run a tach and speedo. Vanguard
redline is 3600 rpm + or - 100 rpm.
I chose to remove governor and tie the original Fairmont throttle to new linkage with a hot rod accessory "bell crank".
When you start a project like this remember, "opinions are like rear ends, everyone has one. Call or contact offline if you have more questions. pumpkincar