Replacing a Mercruiser 5.7

[bprinty]

Unfortunately due to serve water intrusion due to a loose intake manifold, it is time to replace the Mercruiser 5.7l prevortech 2brl carb on my 98 bayliner 2355 with alpha one gen 2 outdrive. i have bought a rebuilt complete "drop in ready" 96 mercruiser 5.7 with everything on it incl new manifolds, and risers. the engine looks identical to what i have it is now other then the air cleaner cover. I believe they are pretty much the same engine, current serial # starts with 0K new one starts with 0F. I have done plenty of mechanical work before on cars, but i have never replaced an engine on a boat and would not consider my self a pro mechanic, but i have plenty of tools and fortunately i have access to a fork lift to use to lift the old engine out and put the new one in, and after getting qoutes from local mechanics to do the work i am left with no choice other then to take it on myself, everything seems pretty straight forward, but would love some advise and any tips or things to look out for from fellow boaters that have done this before, also if anyone knows of any information online like a step by step process. thanks in advance for any help offered

[Ruffryder]

Sounds like you are the one posted on Facebook cabin cruiser owners club...
shift into FWD, pull the outdrive, unplug the main wiring harness barrel / main ground cable, remove the fuel line, raw water hose, shift cable & throttle cable bracket, exhaust manifolds can stay on or removed depends on your opening, undo 2 rear engine mounts, 2 front mount, that engine should be ready to be pulled up.

[SprinterX]

I would chase down the Mercruiser engine manual that is applicable. In there you'll find plenty of details on the re & re of your engine. It'll have info about tooling, drive alignment and testing to complete the installation.

[Nauti_Mike]

Have the Mercruiser manuals will be a big help. As said to remove an Alpha the shifter must be in forward same is true to install it. Aligning the engine is a must to ensure the drive will go into the coupler.

Is this a mercruiser rebuild or a third party rebuild? 1996 should have a mechanical fuel pump while the 1998 may have an electric fuel pump, being a complete package this should not be an issuer for you.

[bprinty]

Ruffryder yes that was me posting on face book, thanks again for the help. Nauti_Mike it was a third party rebuild, the engine now is a mechanical fuel pump and so is the replacement engine. i have already removed the lower unit. I am going to change the bellows and gimble bearing while I am at it, and i will be buying and gimble removal/alignment tool for this

[Ruffryder]

Autozone or Orielys will rent you a slide hammer so the gimbal bearing can be removed.
there's a tool kit will include alignment bar, bellows retaining clip tool , hinge pin tool.
great time to replace the upper SQ shaft/seal.

[2850Bounty]

Suggestions:

Remove the stern drive as per how Joon and Mike have suggested. (it sounds like you've already done that)

Pull the 4 front engine mount lag bolts from the stringers, leaving the actual mounts attached to the engine for now. (there is a reason for this)
Watch closely how you disassemble the rear engine mount bolts, washers, springs, etc so that you go back together in the same order.


Inspect your drive coupler splines.
Inspect your flywheel ring gear.

After the new engine is in position, you will need to align the engine/drive coupler by either raising or lowering the front/side engine mounts.
You will need an alignment tool for this.
The goal is to achieve grease drag marks in a nice even radial pattern around the perimeter of the alignment tool's FWD section.
(see my images below)

Marine Ignition advance curve is critical, and is NOT the same as the Automotive ignition advance curve!
When you fire this new engine up, you will be adjusting for BASE or Initial advance.
Don't stop there....... look further to see what the ignition is doing for a Progressive advance and a Total advance as per your Mercruiser OEM ignition advance curve!

As you no doubt know, the engine must be loaded for proper piston ring/cylinder wall run-in or break-in.
If roller cam/roller cam followers, there is no requirement for run-in for these components.

When adjusting the cam follower plunger depths (what some call adjusting the valves), I will suggest using the 8 stop static procedure.... NOT the 2 or 3 stop.
Begin with #1 cylinder @ TDC on the Compression Stroke.
Adjust the plunger depth for both intake and exhaust cam followers.
Rotate 90*, and do #8 cylinder in the same way.
Rotate 90* again, and do # 4 cylinder.
Continue this following the firing order (1, 8, 4, 3, 6, 5, 7, 2) until you come back around to #1.

I would also suggest that you look closely at your exhaust components. Between the manifold and elbow (and risers/spacers if equipped), you will have seawater transfer ports. These are known for becoming rust scale compromised and restricted. They can be cleared out and brought back to working condition if (key word IF) all of the mating surfaces are good!


This should help you understand what the alignment procedure is about.
NOTE:
The first image shows the system as if viewed from the Starboard side.
The second image shows the system as if viewed from the Port side.















Good luck with this!


.

[fritzman]

Picture for alignment when motor mount block is changed or replaced, tight fitting pipe to spot in front of Eng. mark target, line up jig on target, jig is PVC pipe to fit front pully W/ dust caps 2ea 1/8 hole drilled in caps for centering rod- pointer, it worked for me.

[2850Bounty]

Oh my!

[builderdude]

Oh my!

+1

While I belive Fritz went above and beyond to perfectly center his new aftermarket Diesel engine within his engine bay, the op’s Standard engine swap will not require any special procedures other than the standard drive alignment you have mentioned

[Ruffryder]

bp, yup anytime & welcome to the club!
I told you, we can help.
OP's drive bellows was also compromised .

[2850Bounty]

Earlier I posted "Oh My", and here is a further explanation of why I posted that!

The method that fritzman used is all fine and dandy until you consider:
..... the rear engine mount bolt centers (rear engine pivoting point) do not share an axis with the center of the gimbal bearing.
..... the gimbal bearing oscillates within it's spherical contoured outer housing.

You will get as close as you can with the alignment tool.

[Chief_Alen]

Don't get pissed just asking, what is the shaft called ... the actual propeller sits on ?

#8

http://www.marineengine.com/parts/me...nd-drive-gears

Thought i was having a mad cow moment for a second, yea the drive shaft.

Propeller shaft is what the prop sits on.

# 48

http://www.marineengine.com/parts/me...ndard-rotation

[2850Bounty]

Dave, you'll notice that in my image, I say "technically called a propeller shaft!" In technical terms, a propeller shaft will be both driven and will drive another component.

And yes, the lower shaft is a prop shaft.

[builderdude]

I really didn’t notice until it was brought up. A fantastic image regardless

[Nauti_Mike]

And on rear wheel drive cars the drive shaft is actually a propeller shaft. PS it has U-joints :-) aka bearing cross by some. ;-)

[2850Bounty]

Don't get pissed just asking, what is the shaft called ... the actual propeller sits on ?

......... and so on!

Alen, I would not become pissed nor upset at your comments. Nor would I expect a non-marine mechanic to know the industry terms for these components.
I spent my early years (1968 thru the 70s) working as a heavy equipment mechanic in fabrication. The industry engineers use the correct terms for components like these. Many of these terms carry over into the Marine industry.
Over the years, equipment, automotive and marine components have taken on misnomer names.

Examples of misnomers:

What many of us call a U-joint is actually a bearing cross.... even though you may see "U-joint" on the box!
A splined drive shaft (in engineering terms) is actually a propeller shaft.
What some call a hydraulic lifter today, is actually a hydraulic cam follower..... and again, even though you may see "lifter" on the box!
For a typical V-8 marine engine, we do not adjust valves, we adjust for the hydraulic cam follower plunger depth.
What some call a Dizzy is actually an ignition distributor.
FWC is a misnomer...... these are Closed Cooling Systems.
What many call a marine exhaust "riser" (in most cases) is actually an exhaust Elbow.
Today's engines are not equipped with freeze plugs..... these are casting core plugs.... aka Welch Plugs.
The list could go on and on!


But I'll digress...... and I'll ask that YOU also do not get pissed at me for explaining this to you.
You and/or anyone are certainly free to use whatever terms you like!

[fritzman]

Yes I push the limits at times, but one thig I learned after 50+ years of twisting wrenches, I want things to be a one time task, Marry Christmas.

[Nauti_Mike]

I want things to be a one time task,

"Marry" Christmas ;-)