260 Merc Cruiser out drive

[Keithb87]

We have a 84 ish Caravelle with the 260 Merc Cruiser I/O. It takes on water and we think it is comming in from the accordian boot.
How hard is it to change this? or should we take it to a shop???
We run mainly jet boats, and use this one when the jets are down, (Quite often lately) or for a spare at the lake since it's open bow and seats up to 12 people.
Any input would be appricated.
Thanks,
KeithB87

[mickeyfinn]

Boot is no problem to replace. While you are there you should either replace or service the U-joints and all the boots (bellows) Usually you will have 2 or 3 of them. Not sure with a 260. One iis the drive shaft boot, one is the exhaust and one for the shift cable. You do need to drop the drive off the back of the boat to do it right. Go to the local west marine and by the haynes manual and it gives simple step by step instruction for doing this. If you decide to replace the universal joints DON"T by them from the marina dealer. Take the old ones to your local speed shop and get them to cross them over. You can get the exact same universals (usually) in a different box. Most drives don't have u-joints custom made for them. Good luck. Should only take about 2 or 3 hours.

[75spectra]

If you decide to replace the universal joints DON"T by them from the marina dealer.
I have seen the carnage from exploded automotive u-joints! I WOULD buy them from a marina and make sure they are factory Mercruiser joints. They are diffrent from automotive as most car driveshafts dont normaly bend at 45 degree angles under a load! If you have ever seen a "H"-bar explode you would know what I mean.
By the way the boots are not to hard to replace but you will have to buy a "hinge pin" tool to remove the bell, about $20.00 or so from Merc.

[mickeyfinn]

If you cross a part number for the U-joints you should be able to get an EXACT replacement for the mercruiser part. Will be the same manufacturer, same joint, same numbers stamped on them everything. Just comes in at a fraction of the cost and a different box.

[Havasu47]

75 Spectra is correct. The u-joints up until very recently were made by Spicer FOR Mercruiser to their specifications. They are NOT the same part from the part store. Same dimensions but not the same standards. The genuine Merc. u-joint for an '84 260 is $48.00 each. How much are the ones from the auto parts? $20.00?? Maybe you save $48.00. How long will it take you to change them? Remove the drive, replace the u-joints, (not any u-joint tool will work) re-install the drive. 3 or 4 hours? I am assuming the u-joint are the originals, they have lasted 20 years, not uncommon for a boat that is serviced regularly. We have many times repaired drives and transom assy's from u-joint failures. Not a pretty sight. And almost every one had been replaced with "less expensive u-joints".
I advise you to spend the extra bucks for the good stuff.

[Keithb87]

Thanks for the info. I'll go get the service manual and look into it.

[ECeptor]

A $35 service manual is a great investment and will payback the first repair you do rather than take it to the shop.
BTW, your drive more than likely is an Alpha 1

[Keithb87]

It's my fiance's g-pa's boat. It take on water and it has been getting worse over the last season. It has issues and I think this is where we need to start. Water comes in somewhere around the drive and we can't see where it is comming from.