Another cracked block?

[Joshto]

Hi Folks, a newbie here.

I read every possible thread and youtube videos I could before posting my question here. It seems there isn't a straight answer for it, but many "it depends".

I just bought an As-Is 17-footer (1990 bowrider, I/O 3.0 GM 4Cyl 140 Alpha One, Engine is 1986, I think) without water testing it. Not even on the mufflers. I did it intentionally as the price justified it. The boat came with a good shape trailer, so just selling the trailer would recover what I paid for it.

I did turn the engine to verify it wasn't seized. The engine oil seemed fine, same for the outdrive lube. Spark plugs looked great (rust inside the ceramic insulator, suggesting condensation).

Got it running on the muffles at home to notice there was a 7-inch crack on the block right under the exhaust manifold - port side. I'm sure the boat wasn't winterized by the previous owner. Since I bought it for fun and didn't want to spend much on it, I JB welded the block. Went out to test it in the water. The boat runs awesome! The engine fires up on the spot; runs smoothly and feels powerful. It revs up beautifully. Consistent oil pressure and temperature. It planes quickly.

When I came back to the dock, I rechecked the oil and noticed the dreaded milky oil. I looked at the filler cap, no milky oil there. There is no smoke or high temp, but I suspect the block is cracked inside. The sparks are clean, and there is no water or fuel in the cylinders.

I really like how the boat rides; I wouldn't want to get rid of it. Other than the pressure test (planning to do it this week), is there any other way to rule out a cracked block without taking the engine apart?

It would be a shame if it's cracked, it's such a cool boat. I won't lose any money but would hate to sell it.

Leaving you a video here so you can hear the engine

Thanks for the help.

 

[Boater31]

You can pressure test the cooling side. Plug hoses going to manifolds and remove inlet hose to thermostat housing. Plumb in air supply and bring up to no more then 16psi. If it holds no crack, if it goes down listen for leaks.

 

[Rick Stephens]

Blocks crack just the same on the inside as the outside. Expect the block to be cracked. Find a donor boat with a good block and swap it in.

Rick

 

[Joshto]

You can pressure test the cooling side. Plug hoses going to manifolds and remove inlet hose to thermostat housing. Plumb in air supply and bring up to no more then 16psi. If it holds no crack, if it goes down listen for leaks.

Thanks. If it leaks how do I know if it's a crack in one of the passages or a blown head gasket?

 

[Joshto]

Blocks crack just the same on the inside as the outside. Expect the block to be cracked. Find a donor boat with a good block and swap it in.

Rick

Thanks. Yes, I'm afraid that'll be the diagnostic. I've got everything to change the oil, will probably do the pressure test first.

 

[Bondo]

Thanks. If it leaks how do I know if it's a crack in one of the passages or a blown head gasket?

Ayuh,..... Welcome Aboard,...... Do the air pressure test on the drained block,......

If it leaks, there'll be a big ole crack on the inside, under the crack ya found, on the inside wall,.....

 

[Joshto]

Ayuh,..... Welcome Aboard,...... Do the air pressure test on the drained block,......

If it leaks, there'll be a big ole crack on the inside, under the crack ya found, on the inside wall,.....

I ran the pressure test today. Regret to report that the block is dead. It won't hold 20 psi longer than 8 seconds and, indeed, there is a wheezing sound coming from the port side a few inches below the crack I repaired. To sign the Death Certificate, the oil (milky) level shows twice as high on the dipstick; about two inches over the Full mark.

Good news is that I found the same engine in a Marina for a reasonably low price. It seems I'll be wrenching this weekend.

 

[Scott Danforth]

buy an alignment tool.... you will need it.

 

[Joshto]

buy an alignment tool.... you will need it.

Read that in the service manual. It seems a 1inch pipe can make it just fine.

 

[Scott Danforth]

No, spend the $23 on a proper tool. Dimensions in the stickies, however unless you have access to a scrap piece of steel and a lathe and youre bored to spend the hour to make it, its cheaper to buy the right tool

 

[Joshto]

Hi all. A quick update/ question. I didn't get the engine last week; it will be ready for pick up this Wednesday. Meanwhile, to gain time, I unplugged everything in preparation for the new engine.

two questions:

1) when I removed the outdrive unit, I noticed brownish water in the main bellow. Checked the bellow everywhere and did not see any crack or rip. Where is water coming from? The water intake o-ring? The oudrive gasket? The round rubber seal?

2) when I removed the two front bolts that hold the engine to the floor, they came out relatively easy and the wood they screw into seems to be wet or rotten. How do I fix that without tearing apart the boat ? Can I fill the wholes with some sort of epoxy and then drill them for the screw to tighten again? A friend of mine said I could place a metal plate right across from stinger to stinger to help support the engine. What are your thoughts?

thanks
Josh.

 

[Scott Danforth]

The brown is rust.....
the bellows is leaking

Start drilling to chect the extent of the rot.

Bandaids dont work. Only way to fix it...is fix it right.

 

[H20Rat]

2) when I removed the two front bolts that hold the engine to the floor, they came out relatively easy and the wood they screw into seems to be wet or rotten. How do I fix that without tearing apart the boat ? Can I fill the wholes with some sort of epoxy and then drill them for the screw to tighten again? A friend of mine said I could place a metal plate right across from stinger to stinger to help support the engine. What are your thoughts?

So... There is a chance it was just localized rot, in which case you could drill out a decent size chunk and epoxy a plug back in. Given that, I'd seriously check out the integrity of the transom and the rest of the stringers before going forward with the engine work.

 

[Joshto]

So... There is a chance it was just localized rot, in which case you could drill out a decent size chunk and epoxy a plug back in. Given that, I'd seriously check out the integrity of the transom and the rest of the stringers before going forward with the engine work.

Thanks. Yes, I think the previous owner didn't fully lift the bow while stored and water sat near that area. The hull does not let water in, so I assume it's old damage caused by stagnant water.

I'm working on the essentials right now with very limited budget so I'm looking for a temporary solution. I'm planning to repair the floor and damaged stingers next year. I like this idea, though. What kind of epoxy can I use? I'm seriously considering the metal plate to help redistribute the weight and holding strength.

This is the idea I have. Place a metal plate underneath the engine base (bolt holes will be lined up with the hole in the plate so that would stay the same) and affix the plate to the lateral stingers with bolts (arrows).

 

[Joshto]

the bellows is leaking

Where? I inspected channel by channel, no one single rip.

 

[Scott Danforth]

dont know, you stated it had water in it. only place that water can come from is a leak

the inside of your bellows should be as dry as a popcorn fart.

pull motor and repair the motor mount blocks correctly. band-aid plates are just that..... a band-aid.

take a 1/4" drill, tape off about an inch from the tip. drill parallel to the hull into the mounting blocks (and stringers, and transom) about an inch or so above the inside of the hull, about 6" apart

if you get dry, light-colored shavings, you simply mix up some marine-tex epoxy and fill the holes and go boating

if you get wet, dark-colored shavings, you have rot..... pull the drive, motor, interior and cap, then start your re-hab.

If you get water pouring out the hole.... grab a beer, swear...., then take a deep breath. we have all been there.

your boat is a 1990.... not bad for a 30 year old boat with a design life of 15 years.

 

[Joshto]

dont know, you stated it had water in it. only place that water can come from is a leak

the inside of your bellows should be as dry as a popcorn fart.

pull motor and repair the motor mount blocks correctly. band-aid plates are just that..... a band-aid.

take a 1/4" drill, tape off about an inch from the tip. drill parallel to the hull into the mounting blocks (and stringers, and transom) about an inch or so above the inside of the hull, about 6" apart

if you get dry, light-colored shavings, you simply mix up some marine-tex epoxy and fill the holes and go boating

if you get wet, dark-colored shavings, you have rot..... pull the drive, motor, interior and cap, then start your re-hab.

If you get water pouring out the hole.... grab a beer, swear...., then take a deep breath. we have all been there.

your boat is a 1990.... not bad for a 30 year old boat with a design life of 15 years.

Thanks. The leak is obvious otherwise there wouldnt be water in it. My question is, what is the common entry point of water if the bellow is okay. If brown water means rust, shouldn't that water be coming from the water passage o-ring?
The bell housing gasket is okeish, maybe is the o-ring seems and rubber gasket. will replace both and see how it goes.

If the stinger is rotten or has water on it, it would have to wait until next year no time and money for that. Thanks for the advice though.

 

[Rick Stephens]

Thanks. The leak is obvious otherwise there wouldnt be water in it. My question is, what is the common entry point of water if the bellow is okay. If brown water means rust, shouldn't that water be coming from the water passage o-ring?
The bell housing gasket is okeish, maybe is the o-ring seems and rubber gasket. will replace both and see how it goes.

If the stinger is rotten or has water on it, it would have to wait until next year no time and money for that. Thanks for the advice though.

Water in the bellows can be from anywhere there is a connection, a gasket, a seal, a bellows. All it takes is one or two little things not making a good seal. It certainly can be from the big drive to bellhousing gasket. IMHO, the big square o-ring that is glued into the bellhousing is more for looks than really to keep a leak in the shifter pocket from allowing water into the u-joint bellows. I don't think it is effective at that. And again, IMHO, could be left off a well sealed drive without effect. That said, any leak in the drive to bellhousing gasket or water passage o-ring, will eventually allow water into the bellows. Any crack or bad connection of bellows to bell housing or gimbal housing will of course also leak water into same place.

Unfortunately there is no magic here. With an older boat that you want to make run for a while, start at 'A' and end at 'Z' on your maintenance list.

 

[snoeproe]

For future reference, never put JB weld on a crack that could be fixed by electric arc welding. It slows the job down greatly because of the clean up involved in getting all the jb weld removed.
a cast iron or cast steel manifold (or block) can be repaired by electric arc welding but you have to get everything clean prior to welding successfully. I prefer to tig weld this material myself but it can also be stick welded or even braze welded with oxygen/acetylene .

 

[Grub54891]

Read that in the service manual. It seems a 1inch pipe can make it just fine.

Yeah, we had one come in, the guy lined it up with a one inch pipe two weeks ago. Took the entire family out in the apostle Islands, made it ten miles out and blew the coupler. Expensive tow back in, and we got it repaired the next day so his vacation wasn't totally wasted.
Buy the tool.