Remove drive shaft lower bearing cup

[todd3ponds]

Hi - I've got a 1978 Mercruiser MC1 (I think) sterndrive Model 260 Serial # 5059876 that I'm rebuilding. New drive shaft, drive gear, and bearings. This problem I'm facing is that the new design has a thicker/taller driven gear and shorter lower bearing underneath it than the original (so the height is exactly the same), so I need to remove the bearing cup from the housing, because the old and new size and slopes are vastly different. (and yes, I've got a new drive gear and bearings, as well, already assembled and preload'ed - and the shimming tools)

Any advice on this? I'm about to attempt to use my generic two-arm puller & slide hammer, but I wanted to know if there's an easier/more elegant/less-potentially-damaging way to do this. Anyone done this before? A tool that works well that isn't expensive?

The other concern is: these cups fit in there really tight. When shimming, is the process: press the cups in, install and close up, check the clearance, take it apart, drive the cups out, fix the shims, rinse and repeat?

Thanks!

 

[dubs283]

A standard two jaw puller ought to work for removing the bearing cup. You may need to grind material off the jaws for clearance to gain a tight fit under the cup

For assembly/shimming the process is:

- Set driven gear/driveshaft/top cap bearing preload (6-10 lb/in for new bearings, 3.5-7 lb/in used). Preload is achieved by adding/removing shims under the top cap bearing cup. To check preload use the lower driveshaft and pinion nut inserted into the driveshaft housing (with seal), invert the driveshaft housing and rotate the shaft with a dial inch pound torque wrench

- Set driven gear height using the proper tool and proper face on the tool to achieve .025" height. Shims added/removed under the driven gear cup must be added/removed under the top cap cup to maintain preload

- Set drive gear height with proper tool and proper face to achieve .025" height

Without the proper service manual it's difficult to explain online how to achieve proper gear height and bearing preload

You may be better off purchasing a new/used drive oem/aftermarket. I've heard SEI drives are decent replacements

 

[Scott06]

Hi - I've got a 1978 Mercruiser MC1 (I think) sterndrive Model 260 Serial # 5059876 that I'm rebuilding. New drive shaft, drive gear, and bearings. This problem I'm facing is that the new design has a thicker/taller driven gear and shorter lower bearing underneath it than the original (so the height is exactly the same), so I need to remove the bearing cup from the housing, because the old and new size and slopes are vastly different. (and yes, I've got a new drive gear and bearings, as well, already assembled and preload'ed - and the shimming tools)

Any advice on this? I'm about to attempt to use my generic two-arm puller & slide hammer, but I wanted to know if there's an easier/more elegant/less-potentially-damaging way to do this. Anyone done this before? A tool that works well that isn't expensive?

The other concern is: these cups fit in there really tight. When shimming, is the process: press the cups in, install and close up, check the clearance, take it apart, drive the cups out, fix the shims, rinse and repeat?

Thanks!

I used a slide hammer as well but had to grind down the jaw as mentioned to get under the cup. Yes you may have to do it a couple times to get the right shim. Definitely get the factory manual and you will need the factory tooling to set up the gear height.

you will also need an inch lb torque wrench to set the rolling torque /preload. I bought a $75 beam style one that is just as accurate as the dial style ones I have at work...

 

[todd3ponds]

Thanks for your replies - confirms what I had been thinking. This is a hobby project, so I'm learning how to do it right I do have the factory shimming tools, and the manual. Also, Dubs, thanks for the extra info on setting preload. I'll let you know how it turns out.

 

[Scott06]

Thanks for your replies - confirms what I had been thinking. This is a hobby project, so I'm learning how to do it right I do have the factory shimming tools, and the manual. Also, Dubs, thanks for the extra info on setting preload. I'll let you know how it turns out.

i did my gen 2 last winter, snagged a fishing line around prop seal- when I pulled the carrier I found some corrosion on things despite never having had water in the lube ( the boat sat mostly unused before I got it- 11 yrs /37 hrs).

So I popped the top cap found corrosion on teh up bearing and some staining on the races where the rollers sat. I tore it down and resealed it replaced the bearings in the upper mostly because it was apart. Only the prop seal and the shift shaft seal had an issue. Boat is an 04 with 350 hrs, made a believer out of me on using the OEM parts. I was able to get the bearing numbers off them and order through our bearing house at work same bearings as OEM , most were 50-60% less.

Bottom line if you are mechanically inclined and take your time and follow the factory manual its not an issue and rewarding project. Very similar to doing and engine, trans or setting up a differential in your car.

Also found a bearing heater and or heating up the housings lightly with a torch they will pretty much drop in/on. Also HF seal and race driver kit was good for this as well. To get the carrier retaining ring out with out drilling I broke my 1/2" breaker bar so now I have a 3/4" ...

 

[cyclops222]

Remember.........You will TRY to do it right. A professional might not care.