PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

[gokart83]

I got this with a strong running powerhead. Lower unit is in very rough shape. I was told on a HULL nother forum that my 92 115 rude lower would interchange. I figured out that the shift rod was different but I did the turn count in thing and switched them out. Now the foot wont go all the way up. I measured the driveshaft and there seems to be a 1/2" or so difference. Am I doing something wrong or is there some more work I can do to make it fit? Like cutting off a little bit of the shaft or find a different shaft for the 115 lower? As a bonus, it would be nice to know the gear ratio on these 2 lowers.Any help would be greatly appreciated! My 8 and 10 yr old boys are really getting into fishing and our 16' john boat is getting smaller every time they need new shoes! I really want to get my dads 1993 DC Key West going as he likes to come too.

 

[emdsapmgr]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

You are probably mixing apples and oranges with those lower units. That 1985 140 is a big bore looper engine. For that 1985 year, those V4 engines came with V6 lower units, but had the same gear ratio as the older style V4 crossflow engines. The 1992 115 gearcase is from that prior-vintage crossflow type powerhead. I'm not sure those gearcases are interchangeable. I'm sure you will get further comments from one of the experts on the board.

 

[boobie]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

If I remember right the d/s lenghts are different and also the shift rods.

 

[Faztbullet]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

The 1979-1991 driveshafts are 21-3/4 from mounting flange of unit to top of shaft and the 1992-94 are 22-1/8 (all measurements +/- 1/16) and If I remember correctly a different gear ratio(2:25 stands out) if the 4-5/8(big) housing and stock V-4 is 2:1 Only option is to change upper/lower shafts......

 

[gokart83]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

The 1979-1991 driveshafts are 21-3/4 from mounting flange of unit to top of shaft and the 1992-94 are 22-1/8 (all measurements +/- 1/16) and If I remember correctly a different gear ratio(2:25 stands out) if the 4-5/8(big) housing and stock V-4 is 2:1 Only option is to change upper/lower shafts......

By upper/lower shafts, do you mean there are 2 parts to the drive shaft or are you talking about the mid section housing which looks like 2 parts. Also, can I just cut off 3/8" and file/lathe cut a bevel on the end as stock? It would only be about 1/4" less splines and Im only fishing with this boat. Also, does the drive shaft end fit directly against the power head or is there any clearance there?

 

[Faztbullet]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

The pre 1991 units use a 1 piece shaft and the 1992 and up use a 2 piece.The crank snout on the early looper cranks are longer than the newer ones. I dont recommend you cut the shaft but better to find a shaft or trade unit for one that will work.

 

[Sprky]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

We have cut shafts as a last resort............... I don't care for it, but have not experienced any problems.

 

[gokart83]

The pre 1991 units use a 1 piece shaft and the 1992 and up use a 2 piece.The crank snout on the early looper cranks are longer than the newer ones. I dont recommend you cut the shaft but better to find a shaft or trade unit for one that will work.

If I find a one piece shaft, will it fit my 92 lower unit without any problems? Lots of people here sell foots but we are in a very heavy salt enviroment here. My 92 does not even have the paint wore off yet.

 

[gokart83]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

We have cut shafts as a last resort............... I don't care for it, but have not experienced any problems.

If I cut it I would only have about 3/4" of spines. Does that or the indent being at a different height sound like it wouldnt work? Thanks everyone for all the help!

 

[Sprky]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

First I would determine if the splines are bottoming out in the crank or the crank is bottoming out on the shoulder below the splines...... I don't have an early crank to measure.

Wrap the lower two thirds of the splines with electrical tape, insert and note. Make your decision from there.

 

[gokart83]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

Update! Found out that the shift rod was keeping it from going all the way up. Removed it for a test fit and the drive shaft was bottoming out in the crank. It was only 1/8" too long so we ground off almost 1/4", ground a new bevel and cleaned it all up with a triangle file. Kinda like keeping the 2 piece shaft as it seems it would not bind on the gears as bad if there was a slight misaligment. Now found the V6 shift rod too long and the V4 rod too short. Started cutting threads up V6 rod and broke the cheap auto parts store die. Oh well, Ill go to Graingers on monday to get a better die. At least this is a easy problem to solve. Thanks to all for the help!

 

[gokart83]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

Update-----Still running great after several trips!

 

[gokart83]

Re: PLEASE HELP!! bOUGHT A 1985 140 LOOPER GEARCASE INTERCHANGE

just wanted to put anthor update that the 92 V4 foot that I modified the shaft on just got back from about its 20th or so all day boating trip and still going strong! Very easy to make fit and I would def recommend it to anyone verses an expensive foot if they have the newer 92 up on hand!