GasketCase's SEARS Swamper LT [2018 Build-Off Entry]

LOL, oppys sound awesome.... might get you some ear protection.  After a while it does make your head hurt. 

@MightyRaze you ain't kidding on the ear protection Haha .

Also got a question for you or anyone else that knows  oppys ....  This thing knocks at idle. Ive read that this is normal with them. Is this true?

Cause it runs great and no excessive metal in the oil.  Just scares the hell outta me so I just keep a high idle on it.

I have one that knocks a little like a diesel, but my others do not.  I guess it is a matter of how loud?  If it runs good go for it till she dies.  Maybe idle it up a hair?  Also what kind of OIL you using?  In FL, I would probably run SAE 30 all year round.

GasketCase wrote:

@MightyRaze you ain't kidding on the ear protection Haha .

Also got a question for you or anyone else that knows  oppys ....  This thing knocks at idle. Ive read that this is normal with them. Is this true?

Cause it runs great and no excessive metal in the oil.  Just scares the hell outta me so I just keep a high idle on it.

Both of the ones I have run really smooth actually, especially at a low idle.

Might be the valve lash you are hearing? I clearance my valves on a couple of flatties at around .005 to .003 and got a tick from it but motors run great. Can only hear the tick at idle.

Cool exhuast.  Hopefully your hearing a tic and not a knock.  It's cool to see this build off tractor really come together here.

I do the Ol' screwdriver trick to the block and heads. it definitely sounds like a knock but Ive even opened the back of the block and checked the Rod caps . Wierd oh well.  If she blows before the end of competition, I'll put my KOHLER 15 HP single on there.  This oppy twin is from 1994 and the KOHLER I believe off the top of my head is a 97 .

@MightyRaze indeed I am running sae 30 . Believe me it's pretty miserable down here on the tampa bay.  Between the monsoons of rain we been having , then the days without rain is just terrible at 97 degrees with 100 percent humidity.  Haha.

@Crazy_Carl thanks man I appreciate the support and help as well.

Found some time to mount the LED bar. Also I  was rummaging through my unneccessarily large collection of random parts that I have and found a push mower exhaust shield. Wish it was perfect as is but I ended up cutting so it was straight. Just gotta paint it the swampy green color lol . Take a look .

The heat shield is a nice touch.

I think you should tear the oppy down at least to diagnose it. There’s plenty of time left and push come to shove you could stuff the Kohler in there and join the Kohler club.

@Crazy_Carl read your post this morning and decided to look a little deeper into the noise.

I ran the engine for not even 3 minutes and found the knock is more noticeable from the left cylinder head than the right when listening from the combustion chamber or top of head (Whichever one puts the picture in your head lol) .

Now when I listen along the bottom of the block the noise is the same. I stopped at this point to start build pulley system.

 I think I'm going to drain her and pull the inspection plate off the back of the block and check the crank journals and rod journals tomorrow.

UPDATE:

Found a piece of steel that I found interesting to use for a double pulley clutch.  Again this is an experiment since the first one I built was on my build and I still had a bit of slippage and the pulleys were further from eachother.

So now i built this one

Nice looking clutch! About the noise, your description almost sounds a bit like a worn out bore (piston slap) on the one cylinder. Did you ever try a compression test on 'er?

@AllisKidD21 You beat me to it . I was gonna edit my post before anyone saw it  haha

But like you were saying on the compression test. I literally been staring at this motor in my garage and it dawned on me. I don't even why i havent done it when i have damn compression tester lol I'm gonna check it in the morning. Or maybe now that I'm curious

Could possibly be a worn out wrist pin or worn out wrist pin journals on the piston head or connecting rod. I'm really hoping it's all Good.

If it goes turns out to be a out of round cylinder , I'll just search for another.  If not ill use single kohler (15 hp pressure lube ) while im looking for another engine  cause the big twin honestly looks cool as hell on this small mower

Better not of jinxed me now @AllisKidD21 haha

I've been procrastinating to myself on tearing down the oppy to see for any possibilities relating to the knock.  I'm slowly gaining the energy to do it since it was a pain leading up to getting it mounted on the frame  and after I gave it a oil change .

On the upside , I've finished up mounting the double pulley clutch and I'm having a good feeling on proper operation with no slippage .

Also I installed the tension spring . That got a bit scary like usual. Lol . All I got left to do is build the disengagement linkage and the clutch/belt system will be good to go. NOTE TO SELF : REMEMBER TO HOOK UP BRAKE LINKAGES.

Now that I am looking at the pictures. I may install a idler to correct the belt towards the transaxle

@AllisKidD21 checked compression and both cylinders checked out good. I started the engine and let it idle for awhile and checked the oil again.  Nothing out of the ordinary like before lol. I guess its just like everyone else's.  

Got a little bit done today considering it was mainly dry out but hot as hell. I went ahead and built the clutch disengagement linkages. Determined a good leverage point without having a rediculous stiff clutch pedal.  Came out pretty good.  

Huh, if the compression is good in both cylinders I wouldn't think piston slap would be the problem. Maybe just something like excessive valve clearance or what have you. Either way probably not a big deal.

Great work on the clutch setup! Looks like it should work well.

@AllisKidD21 I'm thinking that it is more than likely what you said with the valve lash . I'm going to check that between today and tomorrow.

And thanks on the clutch compliment. I am currently running the stock 5/8 belt pulley on the crankshaft . Since the motor came from my MTD yard machine. I took the pulley and squeezed it in the bench vice for now but eventually I will put the correct pulley on it.

Build is looking great! I really like the pivot mechanism and clutch linkage, may steal that idea sometime  Are you keeping the clutch pedal on the right side or swapping it over to the left? Isn't your clutch on the wrong/slack side of the belt? The clutch should be on the tight side of the belt, which is on the right if you're looking down on it.

Thanks man I appreciate it , it's becoming my favorite build so far !

@MatthewD I'm pretty sure you want the tensioner on the slack side of the belt ? Correct me if I'm wrong.   . This motor also spins counter clockwise.  So looking at the picture i posted , the slack side will be where the tensioner is now and the pull side Is on the left .

So in motion tensioner side is going towards the transaxle and then comes around straight to the crank pulley and then back to tensioner pulley.  

Also I am still debating on moving the clutch pedal to the left. I want to keep it somewhat original but at the same time I always like custom haha. If I keep the pedal in its position it's in now, I was thinking of installing the throttle to steering wheel itself like the racing mowers .

I have built a somewhat prototype of a gas pedal I may possibly use cause if it was any other build I'd just throw the tacky looking bicycle brake handle as a foot pedal. ( I'll take a picture tomorrow morning and post)

The linkage setup is phenomenal . Doesn't require serious effort like I've had in the past. The tensioner design out shows itself so far .im going to build a skid plate for it as well .  In the morning , I'm gonna put the transaxle on jack stands considering I still have to build the steering system for it but for now Ill start her up to see how the belt system reacts.

Oh yes sorry. I was assuming that the engine turned clockwise and got confused on which side was slack or tight. Yeah you do need the clutch on the slack side of the belt. Found a diagram which shows slack/tight side of the belt when the pulley is spinning clockwise or counter-clockwise. (Not mine)

Might want to recheck engine rotation.

That clutch should be on the slack side of the belt. Looking from below, engine rotation is anticlockwise. Like you have it now, the engine is going to try and disengaged the clutch when the belt is pulled tight. You want the clutch on the slack side, so the belt is sort of fed into the clutch. The engine and clutch will work together to tension the belt, rather than against each other, like in the setup you have now.

@MatthewD yeah it confused me at first when trying GB to design the belt routing .

@"prancstaman yep checked twice too haha. It definitely spins counter clockwise though

@RichieRichOverdrive how is it going to disengage the clutch if it's on the slack side. The picture is taken from the front of mower . I put jack stands under the transaxle and tested it today. and it works perfect.

It’s well designed clutch and simple route so it doesn’t surprise me that it works. If your crankshaft does indeed turn counterclockwise as viewed from underneath your tractor, your clutch is on the tight side of the belt which is under tension and should be on the slack side. I think this might cause some abnormal belt and bearing wear.

As all those above have mentioned about the side of the clutch.  I can see how it "works" with such a strong spring, but it would work better from the other side. 

I run the same opposed in Li'l Red.  This is how mine is set up.



Also, even the best clutches are just average without belt guides on the engine pulley!  Make sure you have those too!

Ok guys , whats your definition of the slack side. Cause i understand what yall mean by having the clutch on the pull side of the belt would cause it to fight against the engine obtaining a result of belt slippage . Now heres a little doodle i did realquick on my phone. Its horrible but itll do .

You are mixing your engine rotation being Up and down.  You are showing your belt in the drawing from the top, but showing your rotation of the engine from the bottom.  

This is what you show in your tractor pictures.  This is what people are seeing in your build.
RED CIRCLE is the engine.


Evidence:
Note the angle (From the Floor) and what side the pulleys are on.



Pulley, counter-clockwise; flywheel Clockwise