Engine swap questions

[drwgblanks]

hi everybody. I have a 1977 aquasport with a 2.5 liter mercruiser and an old merc outdrive. I am getting ready to pull that old merc out and put in a 1997 3.0 merc and outdrive. Am I going to have any problems with the original hole in transom? Also, the mount on the old engine goes across the engine compartment to each stringer. The newer engine's mount is alot smaller. It won't fit all the way across. It rests on a fiberglass support. Would I just use the mount that's in the boat now or build something for the new mount to fit on?

 

[drwgblanks]

Re: Engine swap questions

anybody?

 

[HT32BSX115]

Re: Engine swap questions

You shouldn't have any problems making the new one fit.

You may have to do a little fiberglass work to make the engine mounts match up though. The bolt pattern for the transom plate should be the same.

You may have to drill 2 additional holes for the newer gimbal mount and transom plate.

I don't think Mercruiser has changed their gimbal bolt pattern/cutout in many years.

My Bravo bolted right into the same hole as a King Cobra after I drilled two additional holes at the top.


Cheers,


Rick

 

[drwgblanks]

Re: Engine swap questions

Thanks for your reply. I'm a little worried that I might be biting off more than I can chew timewise. You got any idea's on how long it should take me to do a total swap....wiring and all?

 

[HT32BSX115]

Re: Engine swap questions

Well it depends on how "particular" you are and what problems you find in the transom when you get the old one out.

I ended up doing a bit of fiberglass work in the whole bilge. Well, A lot of fiberglass work.

I did not have to move the engine mount pads. I did have to move the engine mounts though.....so I filled the old hole with epoxy mixed with milled fiberglass and drilled new holes. You may have to cut out the old engine mount pads and fiberglass new ones in.

I also am completely rewiring everything. New fuel-fill and supply lines

everything. I started on this project last DEC. I'm just about ready to drop the engine in. I don't work on it every day and sometimes go a week or more and I don't even look at it.

Yesterday I had the fuel lines installed and had re-installed the fuel tank and was tying everything in place and I decided to turn the fuel pickup 90 degrees to get a better position on the fuel line coming from the tank.

I broke the SOB off in the tank!! (You could hear me all over the neighborhood!!.....lotsa four letter words)


Well I had to remove the tank and get the broke fitting out of the tank and remove the gage sender so I could extract the standpipe, and metal shavings. Now I have to get a sender gasket and make up a new standpipe etc.....A little setback!!


I had a dealer tell me that it would take him a couple of weeks and about $1500-2000 to install. But he wouldn't have done ANY of the cosmetic stuff and would have "haywired" everything. I would have had to re-do everything to my satisfaction.


If all you're going to do is swap it out (you have the harness for the "new" engine?) and you have the hoist already there...it should take more than a couple of weeks to do everything if you work on it every day. I don't know what you have to do on the engine mounts so add for that.



Regards,

Rick

 

[drwgblanks]

Re: Engine swap questions

HT, thanks again for your replies. Sounds like you are enjoying your little project lmao. I actually haven't even inspected the floors yet in this boat. They feel solid, but I need to check them because I'm a little suspect of the old hull. I will also be inspecting the transom when the old drivetrain is removed. So as far as being ready to drop her in....I'm not quite that ready. The old motor is still in the aquasport and the newer one is still in the Bayliner. As far as the "harness". Are you referring to the wiring harness or the plate? I was probably just going to take out everything in the bayliner and put it in the aquasport, except for some of the wires and cables because they aren't going to be long enough. I need to try to get some pics of both. I'll try to do that this afternoon.

 

[drwgblanks]

Re: Engine swap questions

Well I was playing around with measurements. It looks like the 2.5 and the 3.0 are the same block. Is this correct? If it is, then it looks like I can just put the new engine right back on the old engine's mount. I have made some progress. I got the outdrive off tonight and started pulling the gas tank and unbolting engine, etc. Anybody have any tips on getting the engine out? I was going to use a tree and a comealong. After unbolting....it should come right out right? Then I will continue pulling off the transom assembly. I ran out of time to get pictures but I should have some on tomorrow.