boozer

need to install 1.5" drive spacers on xr drives with 2" imco shorties. looks as if it shouldnt be to hard. could someone give me a step by step run through of the process? will i need to drain the oil out of the drive to do this, and if so is there any thing i should know about filling the drive backup?? i know it probably sounds like a stupid question. just wanted to cover my bases before i start. any info is much appreciated. thanks shawn

Wahoo ATV

it is alot less messy if you drain the oil first. To refill it just fill it as usual from the bottom. Make sure you locktite the studs in. Also besure you have 2 Big O rings and 1 small one on each side. Finally, your slip collar that slides over the shaft my fit better one way. There are circlips inside it make sure they allow the collar to slide all the way down the shafts.

Griff

Pretty simple and straight forward. I don't mess with drives much, but I have installed a spacer. You will need 2 of the seal kits for the upper to lower.

As said, drain the lube first and you must fill the lube from the bottom drain/fill hole and pump it in to avoid air pockets.

boozer

ok, sounds pretty strait forward. just a few more questions. dont have the boat here to look at right now. is the oil dain on the imco lower units behind the prop or somewhere else?? and is the a special pump needed to refill the drive and if so where can i purchase one?? thanks for your help

Wahoo ATV

Not 100% sure on Imco but I think it is behind the prop. I just use a garden sprayer to fill my drives

Wild Card 09

I just fitted a 1" spacer onto my Imco lower/XR upper.

Yes the drain is behind the prop, just like a Bravo. I drained the oil until I thought there wouldnīt be anymore in the upper, but when I split them,there was quite alot still oozing out. Let the oil drain for a good while, to save yourself the mess.

The four studs in the XR came out easy (use two nuts locked up against each other. Donīt use a vice grip, or you are sure to mess up the studs) but the two on the Imco lower were really tough to move.

Another little surprise was that the Hardin spacer kit, uses studs that are slightly thicker (along the unthreaded bit) than the original Mercury or Imco ones), the threads were exactly as original, but to begin with, when we offered the drive up, the last 1/2" wouldn`t close up.

I ended up honing out the four holes in the Imco lower (about 1/16") and then it fitted just snug and fine!

If your spacer is from Imco you wonīt have this issue to deal with!
Good luck!

Wild Card 09

The drive oil pump is available from any Merc dealer. There are two sizes. Theya donīt cost much.

I recently got the bigger one and it is way better than the little one that I have been using for years.

Thunderstruck

If the spacer(s) are used make sure the shaft couplers aren't buggered by fitting each end onto the vertical shaft before lifting the lower case up to the upper case. Saves a lot of swearing. I was shaking I was so tired after 10 tries or so. Learn as we go.

OK, cheap test. If the spacers don't work you gonna save the drive oil and put it back in after the spacers are removed?? OR are you gonna save the oil from the installation of the spacers?? I plead the 5th!!!!

Thunderstruck

BTW borrow or buy a stud remover. I could not remove my studs on older Bravos with 2 nuts. Summit Racing has them. If the drives are older the studs will be stuck!! Like he said don't use vice grips.

Use a little grease on the orings to prevent them from slipping.

Croozin2

Not hijacking since this is basically the same question - but in reverse!!! My boat already has 1" spacers and I'm thinking about removing them and trying bigger wheels. So, by the previous posts I understand I'm going to need the O-ring kits from lower to upper, plenty of drive oil, the original length studs and.........? How is the length of the vert shaft compensated for when adding or removing spacers? Do you install a different length coupler? So would I then need a stock coupler? I'm sure I could figure it out once I got it apart but I'd like to have my parts there so I can go right back together with it.