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Engine probs

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"Probable major failure - have

"Probable major failure - have a 95' - 96' Merc IO 5.7 (with carb). All was fine but noticed a hickup or two at WOT. When trailering noted oil in bilge that was coming from the valve cover vents (significant oil in bilge). I cranked and noted the starbord side had excessive air/compression loss that was blowing oil out.

Suspect ring or valve failure - either way I am sure it's time for a rebuild/repower. Boat is in good shape and never have had any prob before...feel more than worth it to have repaired.

Question - I have done rebuilds before (vehicles), but this is a different animal for me...pulling it looks to be a major undertaking since i can't even come close to reaching the oil filter much less the "bell-housing" connections.

Will have to take to the shop - any thoughts on which option to take - buy a crate and have swapped, rebuild/overhall existing etc???"
 
""I cranked and noted the

""I cranked and noted the starbord side had excessive air/compression loss that was blowing oil out."

May have plugged oil returns. How much oil is on the dipstick? Water in the pan? Do a compression check and let us know what you find. If you pull the engine, reinstall w/a remote oil filter and oil drain hose.

A reman. by you would save you big bucks. Not a lot to pull an engine; need a forklift or overhead crane or B&T. The engine hangon components are all old and may need replacement. Buying a complete plug-N-play drop in engine can be worth the money over the life of the boat. Check eBay; several good marine dealers sell there. Check w/your local marina for a package deal to include trade-in of old engine."
 
"Would be great if was not a m

"Would be great if was not a major repair for sure....oil on dipstick is about 1 qt low, which is about how much was in bilge. Was pure oil with no water in bilge and also no water in pan.

Will check compression and advise and thanks...I have checked on Merc replacement long block and the rebuilds from other companies.....must say the cost is way way over what I thought. $ 2,500 low and $ 3,500 high and that is with no labor or shipping etc. NOT GOOD NEWS"
 
"Ayuh,...

Yanking a motor o

"Ayuh,...

Yanking a motor out of a Boat is a piece of Cake, compared to a car or truck...
1st thing you've gotta do is remove enough Boat to get Too everything....

Rapido marine engines is a pretty popular rebuilder over at iboats,...
Several posters have bought long blocks from them...
I think the GM Goodwrench motors are still around $1500./ $1800...
Sands the Guarantee though...

Diagnosing Exactly what the issues are with this motor should be the Focus, rather than just Replacing it"
 
I guess all i know for sure is

I guess all i know for sure is i have a large amount of blow by pressuring things up. I assume if i check the compression and all is good there then at worse I am looking at a top end repair??
 
brad i agree with bondo study

brad i agree with bondo study harder at what is going on before you go jerking parts may be a simple fix
 
"Well - I recon it's offic

"Well - I recon it's officially nut cuttin time...There is dead compression on one piston on the problem side. Have checked and the rebuilds plus labor is simply too high a price to pay right now.....so, am in search of an A-Frame and my bro and i are going to start turning bolts.

Any advice appreciated....have a machine specialty shop located to resurface and work the heads, turn the crank etc...will hone inspect and hone block, drop new bushings and get the dragging starter reworked at the alternator/starter shop....i know to replace the oil pump, fuel pump --- not sure on the following:

(96 model 5.7 Merc I/O in a Bayliner Capri (has lift bed on top of motor)

1- How does engine disconnect from bell housing (assume similar to vehicle - 6 bolts and pull)

2- Is it best to remove the manifolds before the pull

Any tricks of teh trade would be appreciated....once we get it out the tear down should be no prob...the closest this boat has come to salt is a margarita.

I definitely will get the remote set up for oil filter and drain. I want to rebuild the carb too.

Of course all rebuild will depend on what we see once torn apart. If I could find a schematic somewhere on the internet that could be helpful in locating the bolts by brail. I do have an 11 year old that is small enough for me to stuff in the hole to at least get the wrenches/sockets set."
 
That sounds like a good piece

That sounds like a good piece of info...did not think i had to mess with the outdrive...i will read up on the manuel before getting started. Have pulled engines (in cars) but never removed an outdrive.
 
Just for kicks and giggles you

Just for kicks and giggles you might start by pulling the head off and see what you have. It may be a head gasket or burnt or busted valve or whatever. Having no compression makes me suspicious it's the bottom end. Usually there is some compression. At least you will know for sure. Just a thought.
 
"First you pull the outdrive,

"First you pull the outdrive, then you remove the 2 rear bolts, the lags for the front mounts, associated wiring, hoses ,etc, lift the motor up and to the stand"
 
your right puget unless the ro

your right puget unless the rods broke or the rings are all siezed it could b in the head thats a good thought and much cheaper than a repower/rebuild
 
"Thanks all for the info....ve

"Thanks all for the info....very useful and will attempt the head removal first. They got to come off regardless so may as well start there while still in boat.

I have two small panels I can remove from the side walls in the engine compartment, so may be tough to get the manifolds out while in boat. Guess i can leave them on and pull them out still attached to the heads, right???

It is the largest engine for that model boat so not much wiggle room. Sorry for delay in response - we were at da lake for last 5 days in the fishing boat and had a blast - freezer is full again
"
 
"Wonderful....I will check to

"Wonderful....I will check to see if I can get a wrench on them.....only couple inches between manifold and sides of engine compartment, which do not appear to be removable. May have to yank the whole baby regardless."
 
"Thanks guys for all the guide

"Thanks guys for all the guidence...I have reviewed the manuels (motor/stern) and really was surprised at the minimal work needed to pull the engine. Have decided to not even worry about pulling the heads til it is out. Figured why work the top end without going all the way thru it. Plan on dropping the heads and crank at the machine shop - honing the block, swapping freeze plugs and bushings and moving forward. Will have to track down an alignment tool.

Definitely want to install the easy oil change system - get the starter reworked and swap the bilge pump and put in an auto switch on a new one."
 
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