hydro locked 4.3l mercruiser

[Rusty Hartman]

i managed to hydro lock my 97 bryant with a 4.3l mercruiser. it appears the culprit is perhaps dieseling. i got the water out of the cylinders asap and have the motor back running again. it doens't look like any water contaminated the oil.

i had run the boat pretty hard, but idled up to the boat slip thru the marina for a few minutes, so i think it had cooled down fairly well. shut the motor off for a few minutes, and when i tried to start it, it locked up, stripping the planetary gears in the starter.

what are my options?

 

[Bondo]

Re: hydro locked 4.3l mercruiser

i managed to hydro lock my 97 bryant with a 4.3l mercruiser. it appears the culprit is perhaps dieseling. i got the water out of the cylinders asap and have the motor back running again. it doens't look like any water contaminated the oil.

i had run the boat pretty hard, but idled up to the boat slip thru the marina for a few minutes, so i think it had cooled down fairly well. shut the motor off for a few minutes, and when i tried to start it, it locked up, stripping the planetary gears in the starter.

what are my options?

Ayuh,... Did it diesel, 'n run-on when ya turned the key off,..??

Dieselin' is a very noticeable, observable condition,...

 

[Rusty Hartman]

Re: hydro locked 4.3l mercruiser

well now i know this is going to seem like a dumb answer, but i'm not really sure. usually when the motor runs on, it's like you said, very noticeable. this is what puzzles me, to be honest. is it possible that it dieseled backwards and hydro locked quickly enough that it wasn't really even noticeable?

there was only a few teaspoons of water in each bank, and not in all cylinders.

my intention is to install the anti dieseling solenoid to prevent this from happening again. thanks for your help.

 

[Bondo]

Re: hydro locked 4.3l mercruiser

well now i know this is going to seem like a dumb answer, but i'm not really sure. usually when the motor runs on, it's like you said, very noticeable. this is what puzzles me, to be honest. is it possible that it dieseled backwards and hydro locked quickly enough that it wasn't really even noticeable?

there was only a few teaspoons of water in each bank, and not in all cylinders.

my intention is to install the anti dieseling solenoid to prevent this from happening again. thanks for your help.

Ayuh,.... Does yer 4.3l have the 1 piece exhaust manifolds by chance,..??

 

[Rusty Hartman]

Re: hydro locked 4.3l mercruiser

Ayuh,.... Does yer 4.3l have the 1 piece exhaust manifolds by chance,..??

i don't know, honestly. it has the risers with hose attachments at the bottom. if there's a separate exhaust manifold i assume it's sandwiched between the riser and the motor. this is the first i've heard of one piece manifolds. how do i tell for sure and what's the significance?

 

[Rusty Hartman]

Re: hydro locked 4.3l mercruiser

Ayuh,.... Does yer 4.3l have the 1 piece exhaust manifolds by chance,..??

okay since you asked your question, i did a little research, and, unfortunately, it appears i have the one piece manifolds. how do i tell if i have a problem with a manifold leaking water into the motor......by it getting hydro locked? crap.

my wife wanted a boat. i wanted a helicopter......j/k

i'm going to need you to guide me thru this Bond-o.

this boat was exceptionally well maintained....but i assume a manifold could be leaking internally and there be no external evidence of a leak at all?

 

[Bondo]

Re: hydro locked 4.3l mercruiser

okay since you asked your question, i did a little research, and, unfortunately, it appears i have the one piece manifolds. how do i tell if i have a problem with a manifold leaking water into the motor......by it getting hydro locked? crap.

my wife wanted a boat. i wanted a helicopter......j/k

i'm going to need you to guide me thru this Bond-o.

this boat was exceptionally well maintained....but i assume a manifold could be leaking internally and there be no external evidence of a leak at all?

Ayuh,... If they haven't leaked yet, their gonna,...

Yer symptoms say they Are leakin',...
If ya didn't Hear it diesel, it probably Didn't,...

Pull the manifolds Off, 'n inspect the exhaust passages which you can see,...
Chances are, you'll see rust tracks through the carbon coatin' in the exhaust passages,..

There's "Kits" available, quite possibly right here at iboats, that includes the Necessary manifolds, risers, rubber connectors, 'n the cast elbows to retro-fit yer motor,...

Good Luck,....

 

[Rusty Hartman]

Re: hydro locked 4.3l mercruiser

Ayuh,... If they haven't leaked yet, their gonna,...

Yer symptoms say they Are leakin',...
If ya didn't Hear it diesel, it probably Didn't,...

Pull the manifolds Off, 'n inspect the exhaust passages which you can see,...
Chances are, you'll see rust tracks through the carbon coatin' in the exhaust passages,..

There's "Kits" available, quite possibly right here at iboats, that includes the Necessary manifolds, risers, rubber connectors, 'n the cast elbows to retro-fit yer motor,...

Good Luck,....

ok thanks. i was hoping to be able to tell w/o pulling the manifolds. looks like we won't be enjoying the lake much this summer.

 

[Rusty Hartman]

Re: hydro locked 4.3l mercruiser

Ayuh,.... Does yer 4.3l have the 1 piece exhaust manifolds by chance,..??

thanks for your help. i'm not even going to fool around with this. i ordered the complete conversion kit to change to the two piece manifolds. i didn't want to spend the money, but it's a lot cheaper than replacing a motor. this kit with the anti dieseling solenoid should eliminate (i hope) the possibility of hydro locking the motor again.

 

[Bondo]

Re: hydro locked 4.3l mercruiser

thanks for your help. i'm not even going to fool around with this. i ordered the complete conversion kit to change to the two piece manifolds. i didn't want to spend the money, but it's a lot cheaper than replacing a motor. this kit with the anti dieseling solenoid should eliminate (i hope) the possibility of hydro locking the motor again.

Ayuh,... Wise decision on the manifold kit,...

Personally, I think ya threw away the money for the solenoid kit,...

I've got a 4.3l that I've put over a couple thousand hours on, over the last 15 years or so, 'n it don't diesel,...
Anytime it ever did, a tune up usually found the "Problem", 'n I fixed it,..

 

[Rusty Hartman]

Re: hydro locked 4.3l mercruiser

okay, well i can't argue with you. obviously you know what you're talking about. hopefully i can make the repairs and it will be back on the lake by next Friday. We weren't "boat" people, but we're really enjoying it and having a great time!

 

[Bondo]

Re: hydro locked 4.3l mercruiser

okay, well i can't argue with you. obviously you know what you're talking about. hopefully i can make the repairs and it will be back on the lake by next Friday. We weren't "boat" people, but we're really enjoying it and having a great time!

Ayuh,.... You Will be,....

 

[thumpar]

Re: hydro locked 4.3l mercruiser

Ayuh,.... You Will be,....

Yep. After 7 years with our boat and looking for something bigger/better my wife and I have agreed we will NEVER not own a boat.

 

[NHGuy]

Re: hydro locked 4.3l mercruiser

Exhaust manifolds are awkward and can feel pretty heavy if you have a tough reach to put in the bolts. I have an installation hint for you.
Get a couple of long 3/8" bolts. I think they are 3/8". Might be 5/16". Just make sure they are the same pitch as the manifold bolts. Get them longer than the proper bolts so you can grab the with a tool to remove them. Grind off the heads. When you go to install the new manifolds have the headless bolts sticking out of the heads to hang the manifold gaskets and manifolds. Then put some real bolts in the other holes loose, remove the headless bolts and install the remaining real bolts. If your motor is down low and a tough reach this could be a nice time saver.

 

[Rusty Hartman]

Re: hydro locked 4.3l mercruiser

Exhaust manifolds are awkward and can feel pretty heavy if you have a tough reach to put in the bolts. I have an installation hint for you.
Get a couple of long 3/8" bolts. I think they are 3/8". Might be 5/16". Just make sure they are the same pitch as the manifold bolts. Get them longer than the proper bolts so you can grab the with a tool to remove them. Grind off the heads. When you go to install the new manifolds have the headless bolts sticking out of the heads to hang the manifold gaskets and manifolds. Then put some real bolts in the other holes loose, remove the headless bolts and install the remaining real bolts. If your motor is down low and a tough reach this could be a nice time saver.

sounds like a good idea. it's not hard to reach though. i can remove the partitions in the bilge and actually sit down in the bottom of the boat in the engine compartment and access everything fairly easy. looks like a pretty straight forward swap.