Castle Garden 12.5/102

surging? Hmm.... bad intake gasket?

Check and make sure the pins that the butterfly valves in the carb fit nice in their bushings. Those bushings will wear out and cause tons of air to get into the carb and really throw off your air/fuel. Do you get what I'm trying to say? The simplicity did the same thing a while back

mightyraze wrote:

surging?  Hmm.... bad intake gasket?

Gasket is split a little round the bolt holes. I'll put some gasket maker around it

CraftsmanQuad19 wrote:

Check and make sure the pins that the butterfly valves in the carb fit nice in their bushings. Those bushings will wear out and cause tons of air to get into the carb and really throw off your air/fuel. Do you get what I'm trying to say? The simplicity did the same thing a while back

Interesting. I will check that out  I'd say it's just some more dirt in the system somewhere.

Finally got her running the way she should. Runs and cuts well.



When this picture was being taken, the Briggs was running on about 95% paraffin (kerosene). She doesn't smoke hardly at all and I find that once you warm it up on petrol, it runs fine on kero. It does pre-ignite under a lot of load but it's not too bad. Means I can cut my lawn near enough for free.

Sweet, glad you got it running! What was the culprit?

95% kerosene?

MatthewD wrote:

Finally got her running the way she should. Runs and cuts well.



When this picture was being taken, the Briggs was running on about 95% paraffin (kerosene). She doesn't smoke hardly at all and I find that once you warm it up on petrol, it runs fine on kero. It does pre-ignite under a lot of load but it's not too bad. Means I can cut my lawn near enough for free.

The letter series John Deeres were kinda like that. One small tank for gas, one large for kero. Start her on gas, once she warmed up you turn the valve to kero. Don't stall her on kero, you're gonna hate yourself for it. Spend hours draining the carb, priming her, blowing out the cylinders, etc. I think they had a lower compression setup. BTW, I think they were set up for other fuels too, whatever you have to burn off really. Our '46 A has been bored over, can't run her on other fuels for long now. Still has the turn valve and both tanks. It's really interesting what they did back then to save money

That is very interesting. I may need to research that. Sounds kind of cool.

mightyraze wrote:

Sweet, glad you got it running!  What was the culprit?

95% kerosene?  

I cleaned the carb again. I think it was some dirt in the bowl. Yep, kerosene, I've always ran engines on it. The only engines that don't preform well on kero are OHV Honda's. 

RichieRichOverdrive wrote:

Quote :

The letter series John Deeres were kinda like that. One small tank for gas, one large for kero. Start her on gas, once she warmed up you turn the valve to kero. Don't stall her on kero, you're gonna hate yourself for it. Spend hours draining the carb, priming her, blowing out the cylinders, etc. I think they had a lower compression setup. BTW, I think they were set up for other fuels too, whatever you have to burn off really. Our '46 A has been bored over, can't run  her on other fuels for long now. Still has the turn valve and both tanks. It's really interesting what they did back then to save money

Oh right. I never have any problem starting an engine on kero when it's warm. When it's cold just put a little gas in the plug hole or down the carb. I normally start her on gas, let her warm up then drain the gas out and put kerosene in the tank.

So...was greeted today by a puddle below the engine and a cylinder full of fuel. I think the needle and seat have some dirt in them or something. Also the bowl nut gasket was broken so I made one out of card and it's probably leaking as well. This thing never gives me a minutes peace!!! 

Oh no! Have you got a fuel shut-off to help protect against that?

Haha, if this thing ever lets you take a break, do you think you could get a couple pictures of the drive train setup? I'm curious to see what it looks like.

mightyraze wrote:

Oh no! Have you got a fuel shut-off to help protect against that?

Nope but i am going to install one. In the next few days I will take the carb off and clean it again which should hopefully solve my problems.

AllisKidD21 wrote:

Haha, if this thing ever lets you take a break, do you think you could get a couple pictures of the drive train setup? I'm curious to see what it looks like.

Yep no problem. It has a tiny differential case beside the sprocket so it's not a live axle.

So I fixed the fuel leak out of the bowl today. I put a nut gasket from an identical carb onto this one but it still leaked. Went to my local hardware shop and got a fiber washer for 50p. Seems to have fixed that problem. However it is still flooding the cylinder with fuel. When I leave it for 2-3 hours, the cyl. floods enough that it takes quite a bit of cranking at full throttle to start her up. When I blow through the fuel inlet with the bowl off and push the float up it stops the air going through. The float must be sticking somehow. For the moment I'll install a fuel shut off valve to stop the flow of fuel to the carb.

Is it a plastic float or metal? It may need "bent" to close the needle. The float should be level to like a degree wider, but typically level. If plastic, it can be bent with heat, but you have to be very careful.

So I just installed a fuel tap to prevent further leaks into the cyl. I do have a spare carb of this type that I will nick the float off just to see if the tab is not closing the needle properly.

I still haven't had any luck with this mower yet. It's​started to surge again and is still letting fuel into the cylinder. I'm gonna really go through the carb carefully on Monday and replace the float. And I'll get the pics fir you Alliskid. I haven't forgot yet

Isn't that a bugger. Are you sure the float doesn't have a tiny hole in it somewhere? That would prevent the needle from closing all the way and would also cause running issues. And no rush on those pics, I hope you figure the old girl out! Haha.

I'm going to go through absolutely everything to do with the fuel system. I also have to change the oil once i know the carb isn't going to fill the crankcase up with petrol again.

AllisKidD21 wrote:

Isn't that a bugger. Are you sure the float doesn't have a tiny hole in it somewhere? That would prevent the needle from closing all the way and would also cause running issues. And no rush on those pics, I hope you figure the old girl out! Haha.

or hopefully the needle isn't wearing out.

mightyraze wrote:

or hopefully the needle isn't wearing out.

I have a spare parts carb from a 12hp flatty with a broken fuel inlet that I know works good otherwise so I'm gonna take the float/needle etc out of it and put it in the 12.5 carb. Hope it works, I need my grass cut tomorrow.


Got some pics of the drive train.

Pulley on the engine. The belt goes from this to the Peerless 700's pulley via a single pulley clutch.




Under this cover is the 700. 





Removing the grass box allows you to see the axle. The chain comes down from the 700 to the sprocket on the differential. 

Oh I see, it has a Peerless 100 series axle. Cool! Thanks for snapping those pics man!

Ah that's what it is. Thanks!

I replaced the float today and seems to have fixed the flooding issue. Cut my grass today and it works fine. Changed the oil as it was quite thin and about 1/3 gas.

+1 for AllisKidD21 on the float idea! Glad you got it going.

Ah, glad ya got it figured out! You'll be hauling grass in no time!! Haha

Hit another problem. This one isn't quite as severe as i thought it would be. By accident my brother put a long threaded sparkplug (the ones OHV engines use) into the engine. When it turned over, the piston smashed the electrodes of the sparkplug and made a mark on the piston. The crankshaft is slightly bent because it vibrates a bit more than it should and at just above idle there is a slight knocking noise. I assume this is not too much to worry about, but just want to make sure before i cut my grass tomorrow.

Nobody seems too worried Cut the grass no problem today so I'm don't think it's too much to worry about.