# Need advice on rebuilding Onan in Case 446



## ptuptu (Dec 12, 2010)

Hi Folks I have a 446 with a tiller, wood splitter, blade and snow thrower, great rubber, chains and wheel weights (no mowing deck). I bought the whole works for $1000 and all the attachments work great. The tractor itself is a problem. I'm retired and have plenty of time, but I need to learn more about small engine repair. My first task is to invest in some moderately priced diagnostic equipment. I can sure use all the info I can get. Here's the stats on the tractor.

Case 446-779741910
Onan BF-MS3264F B773233748

I also bought a spare Onan from a local guy who was repowering with a Vanguard 22 hp, but it's B43M-GAO163622 Serial C823601846

I read some where that the BF-MS series aren't compatible with the B43M series.

As you can see I'm a total newbie, but I can sure swing a paint sprayer.

Thanks in advance.:usa:


----------



## Hoodoo Valley (Nov 14, 2006)

Welcome to the forum! Those Case units are really neat units. Some of those Onan motors such as the P series and some of the B series are near impossible to get any form of parts for in terms of rebuilding, and when you do find them, they're expensive. I'm not sure on your motor but you might look into the cost of the rebuild before you start tearing in to it.


----------



## cmac (Jun 17, 2012)

Onan rebuilds are expensive (I know cause one if my Cases could one) the rebuild kits alone can run you 1200+ if u can find one, The Onan is a great motor with lots of torque but it will run you about the same or more as a Vanguard Re-Power, The two Onan's are not compatible (short answer). If your bent on an Onan rebuild or replacement there are company's out there where you can purchase a rebuilt one, I believe one is out of Michigan. In my opinion if your looking to "restore" your Case/Ingersoll go with a rebuild. I have have a '93 Ingersoll with a Vanguard that I've been very happy with as well. Good Luck! Enjoy your Case!


----------



## obx (Nov 17, 2014)

Is there an electric fuel pump I can install on my 1975 case 446 onanengine


----------



## Andy1Andy2Andy3 (Feb 2, 2014)

I'd just repower it man


Andy1Andy2Andy3


----------



## tractorfreak34 (Aug 25, 2015)

I agree with Andy1Andy2Andy3


----------



## film495 (Nov 1, 2013)

tune it up and see what happens ... maybe it just needs some love. does it run at all?


----------



## TominDallas (Aug 4, 2015)

This website claims to be the go-to source for Onan rebuild parts. They have published phone numbers and claim to be available to help. Get your numbers ready and give 'em a call, tell them what you've got and what you want to do with it. See what they say.

http://onanrebuilding.com/

Once you've got a parts list and a price, you've got to decide whether to rebuild or replace. I'm seeing B&S engines online in the area of $500-$800 depending who's got them and which model and size they are. If you just want to rebuild for the sake of doing it, a good parts supplier is absolutely necessary and it sure helps to have a knowledgeable parts guy on the other end of the line.
A good machine shop nearby helps a lot. You can give them a block and let them measure and check it out, help decide whether to go oversize or replace.


----------



## tractorfreak34 (Aug 25, 2015)

Hey TominDallas


----------



## TominDallas (Aug 4, 2015)

As far as diagnostic tools are concerned, I think the best thing to determine an engine's condition would probably be a compression gauge and a list of factory specs. What it was from the factory against what it is now? Difference between cylinders. Is it the valves or is it rings and cylinders? There are ways to determine this on your own. You can take the heads off and feel for excessive ring groove. That'll tell a lot.


----------

