Newest of the newbies

[dave68iou1]

I recently purchased a 1985 Thundercraft Citation with a 3 litre Mercruiser 140 engine. I have a leak coming in that allows approximately 2 inches of water in a period of an hour and a half. From what I can gather, I will need to replace the bellows? I have basic mechanical skills (can replace brakes, water pumps, etc. on cars) but don't know how large a job this will be. I'm not even sure what service manual I would be looking for as many of these terms are new to me. On the motor itself, I found a few placards and I'm hoping somebody can point me in the right direction.
Engine. Mercruiser 140, Model MCM140. S/N A433050
Drive Unit: A462307
Transom Assembly: A467994.
Boat has only 482.8 hours on it and I am hoping to take my 3 year old out on it this upcoming weekend. After reading a few posts on here, it isn't looking likely. I need help determining what kind of parts I should be looking for as only basic maintenance has been done to the boat prior to my ownership. Will I need any special tools or parts, and with alot of determination, what are the odds I will be able to get the repairs done before Saturday? I live in Massachusetts and can not find a marine repair shop with any openings anytime soon. Boat will be moored in New Hampshire, so any help in this area is greatly appreciated. Sorry for the long post, but I would really like to start enjoying the lake soon. I plan on going through the easy stuff this week (plugs, wires, coil, distributor, and a little carb cleaner to break the slight hesitation. The prop turns freely (not sure if that means anything) and boat seems to run very well except for the slight leak. Can I cause any damage by running it with the leak? The bilge pump can keep up with it easily and only needs to be run every couple of hours to be safe. Thank you for any help!

 

[Haut Medoc]

Re: Newest of the newbies

Welcome to iboats.....
I don't have access to year of make by s/n, but....
See if this link is helpful.....
http://www.boatfix.com/merc/Servmanl/6/6covr3.pdf
If your drive is pre '91 it should.....
You have your work cut out for you.....
If you drain the drive & find no signs of water intrusion, you are lucky.....
I don't have time at the moment to outline everything, but you should drain the drive, pressure test it immediately to see if it will hold 15# ....
Observe what comes out of the bellows....
Water & gear oil, or just oil..
Gotta go, good luck!......​

 

[jimhen]

Re: Newest of the newbies

Maybe I can offer some slight advice until someone with more experience get back to you.
I am facing the same repair but I am not leaking, so I have asked the what if questions. The water coming in can get inside your sterndrive, and if you run it you may burn it up.
Also if you tear the bellows just a little more, you could sink your boat.
So, best to be patient for now. You will hear back from a sharp mechanic who probably will tell you to get the service manuel and get to work on it.

 

[180shabah]

Re: Newest of the newbies

You will hear back from a sharp mechanic who probably will tell you to get the service manuel and get to work on it.

Who is he talking about???

 

[dave68iou1]

Re: Newest of the newbies

Good information so far. What manual am I looking for? I am familiar with the Chilton's guide on the automotive side, but I am not sure what specifications I'm dealing with (i.e. Alpha drive, are all Mercruiser 140's the same, etc.). Are there online versions of the service manual that I can print out or view? Thanks again for the information so far. I am anxious to get started on this project! The link sent has only the Table of contents on it.

 

[Haut Medoc]

Re: Newest of the newbies

The link I gave you above is the manual for your drive.....
If you run the cursor over the lettered sections on page seven, it will download that section.......
You need to remove the drive asap & see what is in the bellows.....
If you have a fair set of tools & aptitude you will be able to DIY....
You need to gat a grease gun & lube the ujoints & gimbal bearing asap....
You can work on the motor by suppling water directly to the bell housing with the drive off.......
You will need a hinge pin tool to remove the bell housing.......
Remember that the helm must be in foreward for drive removal.....
If water has been sitting in your bellows for long you will most likely need new u-joints & gimbal bearing.....
This is quite a task for a newbie, how much cash do you have to throw at it?
I'd have to say next weekend is unlikely....
I'm sure you want to make sure the boat is ship shape before taking out a young child.....​

 

[dave68iou1]

Re: Newest of the newbies

I am hoping to keep it around a few hundred. I could put more into it, but want to learn the mechanics myself. Is it worth taking to a marine shop and what kind of costs am I looking at? Should I just part ways with the boat if it's going to cost this much to take to the lake? What would the most important repairs be to get this thing on the lake for a couple of days of boating? Which Transom reseal kit should I get for this boat? There are 2 on this link and I'm not sure if either one of them will work. http://marineengineparts.com/shopsite_sc/store/html/page258.html

 

[Jerico]

Re: Newest of the newbies

My boat is an 88 with a 3.0 and Alpha 1. I finished tackling the bellows & gimbal bearing a couple of weeks ago and made my first real outing last Saturday with no problems.

I'm a pretty good backyard mechanic, and the guys here and references they give you are invaluable. It is doable, but definitely not easy. The one that gave me the most problem was the exhaust bellows. On my 3rd try to get it to hold my wife commented "never pay a professional to do once what you can do 3 times."

Follow the manual. Be sure and clean where the bellows connect meticulously, then light sand. The only thing I did against the manual was I did not use bellows adhesive on the exhaust boot on the 3rd try.

By the way, I bought a kit from my local boat shop that included the gimbal bearing, gimbal, exhaust and shift bellows, water hose, o-rings, and lower unit seal for $158.00.

 

[dave68iou1]

Re: Newest of the newbies

How long did it take you on your first try? I have a friend who is a great backyard mechanic that will help. Hoping to get it done on Friday so i can get out on the lake by Saturday.

 

[180shabah]

Re: Newest of the newbies

If you have everything, it is esily do-able in a single day.

Do you have an alignment tool? You must align the bearing and the engine to each other or you will destroy the coupler very quickly.

 

[jimhen]

Re: Newest of the newbies

I found this site yesterday, I am going to get a manual anyway, but this may help you get a quick idea of what's involved. good luck
http://www.outdrives.com/merc/mdtips03.html