3.0 mercruiser rebuild...help!!!!

[michaeli84]

im gonna try to salvage my 89 merc motor by rebuilding it from scratch. i spoke with an older more experienced machine guy and he told me not to do it ill be pissing my money away. however their are remaned motors all over the internet so why not rebuild it. anyway i got water in the block/head when my manifold went without me knowing. it sat for a year its rusty as hek and seized up i need to know where to get all the internal bearings and stuff i need for when it comes out of the machine shop and if im crazy for even considering this whole thing?:

 

[Bt Doctur]

Re: 3.0 mercruiser rebuild...help!!!!

A machine shop will supply the needed components when the crank size is determined.Same with the rod bearings.If you`ve never done one before:
The correct service manual, and read it OVER AND OVER AND OVER untill you understand it.1 mistake and the rebuild was all for nothing
Torque wrench, good quality
have the block boiled and retap every hole before any assembly,
Thoroughly SCRUB the block inside and out.
Obtain a rifle and shotgun cleaning kit to clean the crankshaft oil holes, the lifter gallery shaft and the lifter bores
RE-SCRUB
using #50wt oil, coat crank bearings and insert crank,torque,check clearance
install piston rings and let sit in a coffee can with #10wt oil
put fuel hose on rod bolts and insert in block and torque
install head ,torque is 3-4 steps, in the correct order
Yes, I know there are some things missing but I build them , not type about them. Tricks and shortcuts won`t help if you don`t understand the MANUAL.
IT`S YOUR BEST FRIEND,BUT IT CAN`T TALK YOU THRU THE BUILD.
READ IT,READ IT, READ IT,READ IT, READ IT,READ IT, READ IT ,READ IT.

 

[Fishermark]

Re: 3.0 mercruiser rebuild...help!!!!

i spoke with an older more experienced machine guy and he told me not to do it ill be pissing my money away.

Did he give you a specific reason for not trying to rebuild it? I have rebuilt several engines, including some that were very rusty. Many times the rust is only surface deep... other times the rust goes all the way through. A competent machine shop will assess what you have before you spend much money. They can measure the bore and see if it has been bored out before, etc.

The "Doctur" has written a pretty good prescription for you to follow . Personally I like using assembly lube instead of motor oil for the bearings, but everyone has their own way of doing things. The important thing is to not try and skip the details.

Bottom line - let your local machine shop guide you on the possibility of rebuilding the block you have. Don't be "married" to the idea that you have to rebuild THAT block. There are many 3 liters out there that may serve you better as a base to rebuild... IF your shop tells you that your engine block is too far gone. Just a thought.

 

[littlebookworm]

Re: 3.0 mercruiser rebuild...help!!!!

I'd be a little worried about re-using a block that had sat with water in it for a year. Did it freeze during that time, thereby cracking an inner chamber? Why not pick up a used block from an auto/truck salvage yard? A rebuildable one can be bought for very low cost. Since you plan on a total rebuild, you'd at least know you'd be starting with a block and heads which don't have possible cracks in them. BTdoctor steered you right in the process. Take your time, double-check each step, lubricate each bolt before you put it back, use a clean workspace, use marine gaskets and freeze-out plugs, and be certain you understand and follow the directions and specs in the manual. Good luck. Hy