Time required to remove 7.4l in 268DA

[MMcCawley]

Well I compression tested my cylinders this afternoon and have low compression in four of the cylinders... We've been planning a vacation to Lake Powell in late September so this will likely throw a wrench in things. Anyways I'm contemplating rebuilding the motor in the coming weeks or parking the boat for the summer (our second child is due mid-August so if I don't get moving soon I'll never get things done. Anyways, I have access to a crane and all of the necessary tools (aside from any special mercruiser tools). Can I plan on having the engine out in a day? Any nuances I need to be aware of?

Also to top it all off, I snapped the hose fitting off on my Seaward water heater while I was down in the engine compartment. Not a good day on the boat!

 

[Ten Years Gone]

Can I plan on having the engine out in a day?

I don't know about your tool selection (no special Merc tools needed for engine removal) or wrenching skills, but it should take less than an hour to get the engine out of the boat. Two hours if you're taking your time and being really diligent about labeling wires, hoses, etc. My boat is near identical to yours, and it took me 45 minutes. That was with the drive already pulled off.

 

[CV-23]

Why remove the whole engine? Your heads may be the only issue. How many hours are on the motor? I would only pull it to replace the motor or drive coupler....ask me how I know that!...Mike.

 

[MMcCawley]

CV-23, I may not have to pull the entire motor. Just planning on worst case. I'm not sure on the total number of hours (bought the boat from the marina through lien sale) which is why I'm inclined to go through the entire motor so I know exactly where I stand.

Ten years gone-
45 minutes is remarkably quick. Something tells me you've done it once or twice before. ;-)

 

[Tail Chaser 661]

Really taking your time and going slow like me. Maybe a 1/2 day.
I had my 350ci out in less then 3 hrs.
Very little to take off and disconnect. Drive, motor mounts, 10 P elec connector, ground cable/battery cables, water heater hoses, raw water hose.
Job goes amazingly fast.

 

[Ten Years Gone]

Ten years gone-45 minutes is remarkably quick. Something tells me you've done it once or twice before. ;-)

I've swapped many car/truck/farm tractor engines over the last 20 years. 1st time with a boat. Getting a boat engine out is incredibly easy compared to a car.

The trick is this: Take dozens of photos and videos of everything, from every angle. Have every necessary tool in the bilge/engine room with you. Have a crane ready. Have a driver/tow vehicle hooked and ready.

Disconnect batteries, disconnect power steering lines at the rack, disconnect incoming water line, disconnect exhaust riser bellows from Y pipe, remove two rear transom mount bolts, remove front engine mount bolts from stringers (leaving mounts on block) disconnect shift cable actuators from riser mount, disconnect fuel line at pump or tank. Lift engine above transom, signal driver to pull boat out from underneath the hanging engine. Back pickup truck under engine, and lower away.

Having a portable drill driver with the necessary attachment dispatches hose clamps very quickly. Also, having an air ratchet makes things move faster.
The key is prepare, prepare, prepare. I definitely had more time wrapped up in the initial preparation, but the actual disassembly and lifting out really took 45 minutes.
And remember, I already had the drive off as it was being worked on elsewhere.

I agree with CV-23, you may just need to have the heads reconditioned. Low compression can be indicative of leaky valve seals/seats. But I understand your wanting to go thru the whole engine.
Either way, you will have more confidence in your abilities and your machinery after you have completed the job.
One advantage to pulling the engine...you can really scrub the nastiness that's been accumulating on the bilge floor for decades! :smt038

 

[Rick K]

Your engine should come out a lot easier than mine did in my 245. If the engine hatch would've been 3 inches bigger, I could've slipped it right out. Make absolute certain that you take a ton of high-res pics, 'cause you'll need 'em. I had pic after pic after pic, except the one where all my trim wires hooked to the shifter plate. You see 'em now, but I guarantee you'll forget how they go back together once it's time to reinstall it!

 

[MMcCawley]

Thanks for all of the advice everyone. I'm planning on pulling the motor out on Memorial day. I'm hoping for a quick rebuild but you know how that goes... I'm keep you posted as things progress.