How best to adapt engine?

[thedaddycat]

I have the 7114 and a Kohler 14 single with new piston and rings that came with it. I also have a Briggs 16 twin that I'd like to put in it instead of the Kohler. The Briggs crank is 1/2" higher than the Kohler. I have come up with three ideas for adaptation of the Briggs. Raise the BGB mounting plate(and BGB) up by 1/2". I don't think there's enough room to do that and still have clearance for the rods and linkages above it. Lower the engine mounting plate by 1/2". Weld angle iron to the frame, then cut out the bottom of the frame and weld it to the angle iron. With the sides of the angle iron pointing in towards the middle of the frame to act as a shelf for the bottom to rest on, you can modify it so that it is reversable in the future. Weld the bottom of the frame pan to the edge of the angle iron under the tractor, leaving the original frame cut alone. To restore, cut the angle away from the frame pan, lift into place, tack it and then just weld it up. This third idea is a little out there, but in theory could align the crank and BGB input shafts close enough for the coupling and flex plate to handle without modifying the frame. Put washers under the front engine mounts, between engine and frame. This would tip the BGB end of the crank down towards the BGB. Put washers between the frame cross plate and the top BGB mounting holes to tip the BGB input shaft up towards the engine. This could also be done using plate that had been ground down at an angle to give the desired effect. The trick is to get the angles right..... Now I know there are many out there who will have opinions on this, please don't be shy about telling me how crazy this idea is......

[SmilinSam]

Kind of interesting.. All the Briggs 16's I have seen , both flat opposed and V twin have had the cranks lower than whats supposed to be and the engines need raised up. Got any Pictures Daddy????

[HubbardRA]

Kirk, I ran a 12 Hp Kohler from a Cub Cadet by making spacers to sit the engine on and drilling new holes. The crank was about 1/2 higher than the B/S setup. Ran it for several years with no problems. In my opinion the slightly increased angle is not as critical on BGB wear as having a preload or compression on the driveshaft and BGB shaft. If the rear yoke is allowed to float on the shaft during assembly, with a loose set screw until everything is tight, then there is neither an upward or downward force on the BGB shaft. This is the main cause of failure. I assemble the driveshaft completely, align the flywheel bolts horizontally, then tighten the rear yoke setscrew. I have had three different engines on the 61 Wards other than the original, and I am currently running a different engine on my AC 716, and have had no BGB or flex joint problems. Remember the Wards tractor has seen very heavy loading with about 12 years of tractor pulling (20 - 30 pulling runs per year) and lots of towing use around home. I am just now converting it to a work machine. The main thing that you need to be careful of is that you have to make sur that the BGB shaft and the engine crankshaft are parallel. If not, you will be putting a pulsation into the gear train. This is hard on BGB bearings. Parallel is more important than having a low angle. The flex joint or a universal joint puts a pulsation into the driveshaft, the other one removes the pulsation, providing the shafts are parallel. The more angle, the more severe the pulsation, but the joints will take care of it if the shafts are parallel.

[thedaddycat]

Here are the two engines side by side on the garage floor. The Kohler is on the left, Briggs on the right. I also thought of this since the last post. The earlier tractors used a rubber compound type coupling, maybe 1/2" thick. Would that type be better than the thin flex disc? What I'd like is to leave the frame unaltered if I can. I am still undecided about which engine to use, but have time to take a good hard look before switching to the Briggs. In its favor it has more power than the Kohler, and the twins are smoother from what I hear. Down side is why I posted this question, adapting it to the tractor. Fuel use and maint. costs I have no idea on what it would be, nor on how many hours are on it. The Kohler is fresh, new piston and rings I was told. It is not fully assembled, and would be easy to take down to check valves, etc. I also have an electric PTO clutch on a 12 HP Kohler that I may be able to just move over onto the 14, I'll have to check it out. It needs no mods to the tractor since it's the stock engine. Not a lot of down points there..... I guess the real question is, is 2 HP and a smoother engine worth what it will take to make it happen. If Option #3 plays out, the answer is yes for sure.

[MikeES]

Is there a shallower oil pan available for the Briggs. Just a thought. BTW the K301 and K321 blocks are identical (piston bore only), the front clutch should work just fine.

[BLT]

I scored a piston on my 7010 Briggs 10 HP two summers ago, and while I was agonizing about tearing it all down to get a bore job, I have an 18 HP Briggs IC and thought about putting it in. I have dimensional drawings on both and did dimension checks between the two while the old one was out. I think I would have lower the mounting buttons one inch and then to clear the cylinders I would have need the "gas axe" to clear the side rails. Luckily, I saved the bore on the old one with a hone and put in a new piston and chrome ring set and re-installed the old engine. It seemed a little much for me to tackle. I lucked out last week and got a Sunstar dirt cheap and when you run both engines wide open the vibration between the sinle and V twin doesn't appear to be that bad. When it gets down to power my "ole" 10 HP Briggs will handle a 48" deck quite well on a normal lawn cutting. I admit on the first cuting in spring will make it snort.

[PatRarick]

Every opposed twin I have seen is the same height. Have never seen one that is lower. Just looked in the parts book, and there is no other oil pan available. An idea may be to have the top or sealing side of the pan planed down by the necessary amount at a machine shop. May have to shorten the oil slinger slightly, or could maybe get by with cutting a groove in the bottom of the pan to allow clearance. Pat

[HubbardRA]

Kirk, As I have said before, it is your decision. My opinion, I'd put it in like it sets. You may have to add some spacers to the driveshaft bolts at the engine. You want the rear yoke as far up on the BGB shaft as possible to eliminate leverage on the shaft in case there are side loads. When I used the Cub Cadet engine, as I said earlier, it sat higher. I had to make an adapter to hook the driveshaft to the flywheel and also had to put tubing spacers on the bolts that were about 2 inches long so that the driveshaft would bolt up without any modifications. I've never had any problems with these setups. A one cylinder Kohler is rougher than a one cylinder B/S. A two cylinder is much smoother. I put a two cylinder Vanguard on a Murray mower that I had to replace the B/S one cylinder. It was like climbing out of a VW Bug into a full size Cadillac. That V-twin was so smooth and quiet that it was unbelievable after using these one-lungers for so many years. Go for the twin, it will work.

[PatRarick]

Another idea would be to replace the driveshaft and coulpers with universal joints and a straight shaft. That is how the Sunstar engine is connected. My wild idea of planing the pan has got me intrigued. I am going to look at a 16hp opposed today to see if there is enough flywheel or blower housing clearance, then pull it apart and see how well this possibility will work, as far as having to alter the oil slinger. Want to keep the proper lubrication. Kirk, I assume your 16 horse is the splash lube, rather than the pressure lube? Just checked the books, and the exact difference in crankshaft height is .465". The cast iron single is listed as having a 6.125" distance from mounting feet to crankshaft, while the opposed twin is 6.59" Pat

[HubbardRA]

Pat, Kirk, Universal joints give the same pulsation as a flex disc. What you really need is a constant velocity coupling. You could use the flexible couplings that are used with pumps and other devices. Two pieces that mount on the shafts with three fingers sticking out. these then interface with a rubber insert with six slots. These cause no pulsation because they don't have a cross type joint. With the length of a Simplicity driveshaft, raising the engine shaft 1/2 inch will only change the angle about 1 degree. I don't think this is enough to worry about.

[Leroy]

Well im in the same tractor just 3-5 hp off with trying to put in a 20 hp Onan were a 17 hp Kohler was. on a 7117 The drive shaft kit is not there the old one on the kohler was kept by the old man who has all my lawn more service jobs. But the memory is failing him. He is 85. I did ask him and he said he didnt see it, Oh well. Now when i go to "A" dealer not Simplicity But i did buy it from them ,and ask for a Onan coupler to the Simplicity. "no such Critter". So i have to manufacture one. While i have an alshimer patient living with us . Wifes Grandpa. And he is a neat freak But he moves my stuff and can't remember 15 minutes ago. I dont know if i will ever get this thing going again. with the work that the housework needs and automotive repairs and cleaning up after Grandpa's accidents so the wife doesn't pull all here beautifull hair out. Retireing from 3 things would be nice, Chasing my tools and bolts and washers down that gramps moves ect. The thing is this Guy has 6 kids and my wife is the only one who would devote her time to take care of this man. We are overloaded. But im interested in ideas on a kit to make the connection to the 7117 with the 20 hp Onan. Any Ideas welcome cept fer sellin it. Leroy

[thedaddycat]

I have one day shift left to go and then I'm on vacation for two weeks...... I'll pull out the twin and set it in the frame for a quick look at how it will fit. The 7114 seems like it is a lot longer than the 3310. I wonder how much room to the front there'll be with the twin in there. I'll post pics in a few days..... From many posts I've read, I have a question. Are any front mounted implements on the 7100 series powered from a front PTO or are they all center PTO driven? If none are front PTO driven, there'd be no reason to mount the electric clutch on the Kohler. I have a feeling I'll be looking at Dutch's Hybred Hitch plans again soon....

[HubbardRA]

Kirk, I can't answer for a 7100 series but the 7000 series uses front PTO units. I'm just not familiar with the 7100. I'm thinking maybe they are the same chassis as the 7000, but I have been wrong before.

[UCD]

Kirk My 7790 is a 7100 series chassis. The diesel has no provision for a front clutch every thing runs from the center PTO

[Kent]

I've heard that the 7100 series frame is slightly longer in front than the 7000 series, but I don't know exactly where this added length is...

[UCD]

It is stretched in the middle. Wheel base is longer.

[MikeES]

Kirk, I have seen a 914S with the front clutch. I believe the early single cylinders used the front clutch, I think they went with the center PTO for the twins and then decided to use it for the singles also. I dropped a KT17 opposed twin into a 916 (same as a 7116) just had to cut the side rails of the frame for the twin cylinders to clear. The mounting holes for the twin were already in the engine plate deck. Everything else including drive shaft, couplings even electrical plug worked. I have noticed that later 900/7100 series had all frames cut for the twin even with a single cylinder engine. The diesel had its own frame.

[UCD]

7116 Frame

7790 Frame

[thedaddycat]

I was just looking back over some stuff and noticed that just in front of the lower front end of your box, the cross brace is also cut away in the 7790 frame. I'm revisiting that 16 horizontal twin Briggs in the 7114 idea, with a twist....... I saw an ad for a tractor with a V-twin 18 HP for $300, thinking the V might fit better that the flat twin....