Swap Lower Unit from johnson 110 to 140???

[mbecke2]

DISASTER STRIKES AGAIN!! Finally got my motor running again after 1600 bucs and well you guessed it, soon as I take it out, the lower unit blows!! Anyway I got on a plane for about 5 seconds and bam the entire boat starts shaking violently and the motor looked like it was goin to jump off the transom. I'm not sure what happened but now when I put it in gear the prop doesnt spin and it revs up like its in neutral. SO I have a 1986 JOhnson 110 vro (not running) and I was wondering if I could use the lower unit from that motor to fit in the 1988 johnson 140 vro. Looks the same size, but I'm not sure if this will work. ANyone know the answer??

 

[SparkieBoat]

Re: Swap Lower Unit from johnson 110 to 140???

there is a lower unit interchage post in the secret files section...I know that some 140s came with the bigger gear case..but my guess is yours will work fine..even if you had the larger type gearcase on the 140 it will still work.

 

[Faztbullet]

Re: Swap Lower Unit from johnson 110 to 140???

Sorry but no......the 120 and 140's use a different gear ratio(2.25) than the V-6 cases(1.86) and V-4 units(2.1) and the driveshaft lenght different due to crankshaft being longer....

 

[SparkieBoat]

Re: Swap Lower Unit from johnson 110 to 140???

but he is not using a V-6 foot..he has a 110 and is putting it on a 140...that should work fine shouldn't it?? I dont know where you saw anything about a V-6?? maybe another post..they all run together sometimes

 

[Faztbullet]

Re: Swap Lower Unit from johnson 110 to 140???

No as the 1988 140 is a small bore looper engine,not a crossflow. If it was a crossflow it would work. A lot of of these engines came with the V-6 case(15 spline) and people think its the same as the V-6 but ratio is different. This engine also came with the small V-4 case(13 spline) but they dont live long as the looper has more torque than the crossflow.

 

[SparkieBoat]

Re: Swap Lower Unit from johnson 110 to 140???

so could he swap the drive shaft out and use it?? If not, he could use a V-6 foot, but he would have to re prop to compensate for the gear change, is that correct?? Or is it worth it to hunt down the right foot? I know I have seen a lot of the late 80s 140HP motors out there..must have been a very popular motor for some reason. so it should not be that hard to find the right foot I would think.

 

[mbecke2]

Re: Swap Lower Unit from johnson 110 to 140???

I found a 1984 140hp will this one work???

http://www.louisianasportsman.com/l...d=266889&sid=d5400a54dc8da56bbea7424f0d68bce6

 

[levi_tsk]

Re: Swap Lower Unit from johnson 110 to 140???

nope that is also a crossflow engine youll need one your year model and up to about '96 the engine the lu comes off of has to be a loop charged engine aka looper

 

[Faztbullet]

Re: Swap Lower Unit from johnson 110 to 140???

I found a 1984 140hp will this one work???

Sorry ...but no. You need one off a 1987 and up 120/130/140 Looper.

so could he swap the drive shaft out and use it??

Only if it was same size case and it would have to be reshimmed as its a 1 piece shaft, the 2 piece didnt come out till early 90's.

If not, he could use a V-6 foot, but he would have to re prop to compensate for the gear change, is that correct??

A V-4 looper with 1.86 ratio struggles to get up(been there/seen that) so reproping isnt a good option. Say if its running a 17p @ 5500 with 2.25 ratio, you would have to drop to a 13p with the 1.86 ratio to get the same speed and it still would be slower planing.

Or is it worth it to hunt down the right foot?

Yes it better to find corect that try to get by.

 

[SparkieBoat]

Re: Swap Lower Unit from johnson 110 to 140???

you are da man Faz....I am trying to store all of the valuable info you give out in my pea sized brain...this post needs to be archived.

 

[mbecke2]

Re: Swap Lower Unit from johnson 110 to 140???

GOOD NEWS!!! I swapped the lower unit and it was a perfect match. Only thing I had to do was swap the shift rods which was simple because they screw right out. The drive shafts were identical in size and spline count. The gears shift great and work fine. Took the boat out and it ran fine. I got 5000 rpm at WOT with a 19 pitch prop. A little slower out the hole. I forgot the gps so don't know the speed but I'd guess I went around 40mph. I unscrewed the drain hole from the blown lu and water drained out for 1 minute and then nasty black sludge smelled rotten, metal shavings everywhere. Guess it blew a seal/gasket. Is this lu from the 110 going to last in the 140 looper powerhead??

 

[tx1961whaler]

Re: Swap Lower Unit from johnson 110 to 140???

I unscrewed the drain hole from the blown lu and water drained out for 1 minute and then nasty black sludge smelled rotten, metal shavings everywhere. Guess it blew a seal/gasket. Is this lu from the 110 going to last in the 140 looper powerhead??

Not if it gets water in it like the last one.........

 

[mbecke2]

Re: Swap Lower Unit from johnson 110 to 140???

Well I need to figure out what caused that so I can learn from it and not let it happen again. So how do I prevent it from happening or check to make sure it don't have water. Where are the seals and how do you check them?? I guess I should drain the lu oil every once in a while to make sure there is no water.

 

[nymack66]

Re: Swap Lower Unit from johnson 110 to 140???

GOOD NEWS!!! I swapped the lower unit and it was a perfect match. Only thing I had to do was swap the shift rods which was simple because they screw right out. The drive shafts were identical in size and spline count. The gears shift great and work fine. Took the boat out and it ran fine. I got 5000 rpm at WOT with a 19 pitch prop. A little slower out the hole. I forgot the gps so don't know the speed but I'd guess I went around 40mph. I unscrewed the drain hole from the blown lu and water drained out for 1 minute and then nasty black sludge smelled rotten, metal shavings everywhere. Guess it blew a seal/gasket. Is this lu from the 110 going to last in the 140 looper powerhead??

I am running a LU from a 1978 140v4 (crossflow) on my 1987 140 v4 Looper, swap the shift rod like you mentioned bolted up like a glove, most importantly its a 2:1 ratio and 13 spline ..
Metal shavings is NOT good ...Sign on gears chewing up or clutch dog ...
Notice the vent holes above the cavation plate ? 1978 v4 LU