Mercury V6 School for lower units

**TEXAS20225** · 04-28-2020, 02:30 PM

its different times! its case by case!!I have had some that i worked on way to long most all of them were Sportmasters not so much CLE or Torqmasters( which is my favorite Gear case) experience is everything i wont go in to the shim results adding a certain amount of shim does not always produce a equal amount of change!! Just read and understand if you dont understand find out what it means , i taught my self how to rebuild gear cases over a very long period of hard knocks, i also learned the basics of motor rebuild a long time ago from a good friend and accomplished motor man Tommy Warren he started all this stuff, i have since developed my own style of building thru much blown money and parts on machine shops and my stupidity of taking their word for it and trying to believe a business owner

believe me it just aint so in every case know them who labor correctly by there track record not by what they say just my .02

**LakeFever** · 04-29-2020, 01:34 PM

Tex do you use marking compound to test contact pattern in your builds?

**bbezok** · 04-30-2020, 06:31 AM

could someone tell be if a 1993 XR6 4-1/4" case ratchets?

**Capt.Insane-o** · 04-30-2020, 08:31 AM

Yes

**bbezok** · 04-30-2020, 08:34 AM

thank you!

**Aaronhl** · 07-10-2020, 04:13 PM

Originally Posted by TEXAS20225

it is the big bearing ratcheting case just before was a preload 1647-9147,9147- C,9147-C1 were all big bearing ratchet

So I know the C2/C3/C4 lower units do not ratchet like the C/C1 units, so other than taking the lower unit off and looking at the number itself, are you able to spin the prop in gear to verify if it is a C/C1 unit if you hear the clicking sound? Will the C2/C3/C4 units make the same noise when you spin the prop or is it just locked up? School me

**LakeFever** · 07-10-2020, 04:45 PM

I have both. You can spin the ratchet backwards by hand reverse of whatever gear selected and the non ratchet doesn’t move at all when in either gear

**Merc 2.5** · 07-10-2020, 06:23 PM

The clutch dog is square on non ratcheting, the clutch on ratchet has a ramp on 1 side so it can spin backards but lock forward, vise versa with reverse , of course I think there is sum bigger or better bearings in the ratchet unit also. Just little fyi , and I hope I'm rite that the rite name for that part is clutch dog lol. I have 3 units and all ratchet , 1 unit has no c

I wanna start learning more bout these things to , but like texas says. Bout only way to really do that is to just do it urself , I'm tryin start gather the tools needed

**tnelsmn** · 07-27-2020, 03:05 PM

Are you able to interchange a bearing carrier with a drain plug into an older preload case? I have a 1647-6670 preload case I want to cone, but would rather not have a big hole leading up to the drain plug after adding a nose cone if that makes sense. Any specialized tools required for that job?

**LakeFever** · 07-27-2020, 03:15 PM

*edit* whoops I dont know about the pre load case, I have this for a Big bearing non preload case. A stock 2.4L 200hp case is what im working with. Original answer below;

Yes I have that exact set up a welded and filled drain plug with a sporty bearing carrier. The sporty carrier is for the hipo shaft though not the stock small shaft. I dont know off hand if there is a small shaft drain style bearing carrier. Someone else will have to chime in on that

**Dave S** · 07-27-2020, 03:22 PM

Pre load cases.....are …. week....the pin gear wants too get away from D/S.... it will over 200 hp I like pin cases.... fur 2.0 motors.....2.5s need more surport,,,,,,but the pinipn pushes up to the D/s spline/ main bearing....Ratchy cases don/t Break the cam follower…..Chunk cases,,,, if run in a sand will berak the cam follower and ya go only rev.... to the bar...….

**Merc 2.5** · 07-27-2020, 03:26 PM

I have a post sumwere around here wondering bout the 2 diff units , people say the unit with pin on top drive shaft dosent ratchet? I have 2 that have that pin but they both ratchet in both gears , so I'm just curious

**tnelsmn** · 07-27-2020, 03:32 PM

This is off a 2.0 175. It’s an old case, late ‘70’s. It has the spring loaded pin on top of the DS leading me to believe it’s a preload, but it does ratchet. I figure I’ll cone this one and run it while looking for a better case.

**Aaronhl** · 07-27-2020, 06:32 PM

Originally Posted by Merc 2.5

I have a post sumwere around here wondering bout the 2 diff units , people say the unit with pin on top drive shaft dosent ratchet? I have 2 that have that pin but they both ratchet in both gears , so I'm just curious

I only have ratcheting C lower units. I have a couple working units, and a couple for parts/rebuilding currently, so I do not have any experience with the preload style, or non ratcheting units. When I am looking at online classifieds, I am trying to get good at spotting a C or C1 unit by the pictures or seller description/engine serial...I would hate to drive a couple hundred miles if I was gonna buy one to find out it's not what I was expecting...

Hard to tell the type of lower unit when it is on the mid section. If it was off, you can usually see the driveshaft pin.

I first look on the side of the over unit to see if it has the plastic cover near the water inlet holes, I believe those are all preload cases from the early 80s.

If there is no plastic cover, it could be a ratcheting...Any preload models without the plastic over??

**LakeFever** · 07-27-2020, 06:58 PM

Almost all of the lowers with the anode are not ratcheting. There are some but it’s a good rule of thumb that if it has the anode it doesn’t ratchet. The little gills over the water inlet are usually ratchet cases bb style. At least that’s the case from what I’ve seen the last few years