4.3 Marine Aftermarket School of hard knocks

[iskiglass]

Hi guys,

This is a very sad day for me today as my boat engine saga continues.

Here's the skinny:

I had purchased a new aftermarket replacement 4.3 motor that ran perfect all last year until the end of the year when we found water in the engine and ASSumed we cracked the block and or blew a head gasket, possible from a lean condition backfire, etc...after flooding during hurricane... Unfortunately my boat guy and I never diagnosed the source of the water because instead we lucked out and got a free replacement block sent under warrantee.

I had the same guys set up the new block with all the old parts and I opted to go with the existing exhaust as they appeared perfect having been a mere 5 years old in freshwater only, northern, low hours, GLM 3", and I was very clear that they should be inspected before putting them on. I said if there are any signs of problems of course let me know because we can't screw up this block. He agreed they were probably fine and said they looked good after "inspection".

Turns out the exhaust were put back on and but they had never separated the exhaust where the previous boatyard had used the WRONG GASKETS for the type of thermostat housing apparently. They were closed instead of open...(?) I had changed over from the one piece mercruiser to the GLM two-peice cast iron to avoid problems, OMG. WHat a complete nightmare this all is for me and my family. I am leaving out a lot of drama and saga trust me.. All summer without a boat etc...

Never would have known anything was going on as the boat was running perfect again when I finally got it back except at WOT where it would ping ever so slightly. Actually my buddies said they couldn't even hear it... SO I brought it back and now they said it was running 50 deg F hot on one side (opposite from temp send of course) and that that may have been why it was pinging... So I agreed they should change that and since then voila water is flowing properly now and cooling both sides correctly.

Her's the rub - the dispstick is now showing a quart high on the stick. it is clean looking oil so far but I am beside myself. WTF. I am test driving it on SUnday and hoping for the best but please help me clarify the scenarios so I might sleep a little better tonight.

So worst case is that I now have a brand new motor with a freshly (2 weeks ago) cracked block, or a blown head gasket, or then what else could it be risers, or exhaust manifolds correct?? I need help here as I am only a beginner still although learning the hard way... What do ya think? Please try to include some best case scenarios along with worst as that might be good for me until SUnday when I will run it hard and pull the oil.

One thing I noticed is the dipstick is below the alternator arm and looks out of place like maybe it should be more upright and above that arm maybe and somehow it is now giving odd readings because the stick is not stock and set up correctly... It has an added adapter on the bottom from a crossthreading done by previous $80/hour boatyard. I am sure this is very wishful thinking probably but has anyone ever seen that scenario?

When running on muffs it was just 50 hot so probably only like 240 Deg F although under load it may have been hotter...
What are the likely scenarios and chances I won't be screwed and boatless for a long time. Please give me your ideas thoughts and advice as i try to get through this AND still take care of my childrens needs for food etc. I want to laugh but it is hard. Thank you! I really appreciate the advice here.

 

[Maxz695]

Re: 4.3 Marine Aftermarket School of hard knocks

You say the oil is higher than it originally was before this occoured? I realize you say it looks clean. You also say it runs cool now like it,s supposed to. The wrong gaskets where on there that may have let some water into the oil. I would suggest that before you do your sunday was it run to change the oil and then re inspect it when you come in and see if the level has increased. If so then I would think there is definitly a problem. EDIT If you want to be dumb and risk all the work and money you spent on your engine which is according to you PINGING!!!! (Water ihn the oil) for the sake of $15 dollars worth of fresh oil, clean oil to lubricate the engine then you get what you have coming. At the very least even if it is still getting water there may be enough new oil to keep the engine going without seizing up. Not being mean here I,m trying to talk some sense into you. My thinking here is you say risers meaning V6 V8? anyway I,m sure your not running a fresh water cooling system and you have salt water in your oil in which hopefully to this point hasn,t done any or much damage to the internels from running it until pinging occured with salt water in the oil through the exhaust and into your crankcase! Drain the OIL!!! Save your engine!!! or pay the piper!

 

[tpenfield]

Re: 4.3 Marine Aftermarket School of hard knocks

It is tough to say what the best course of action is at this point. I think the chances are slim to none that you will get out of this easily.

I assume that you have been getting re-manufactured long blocks as your replacement engines. The problem is that they can be a roll-of-the-dice in terms of their longevity. Then the questions arise about the skills of the mechanics that you have working on the engine.

I went through a process myself over the past year where I was having trouble with my engine. I figured it was the manifolds . . . I rebuilt the top-end of the engine (cylinder heads) and replaced the manifolds and elbows. I got about 6 hours on the engine after the re-build and the thing hydro-locked and destroyed itself. :facepalm:

It turned out that the cylinder heads were rusting through around the valve guides and that was the problem to begin with. I ended up selling the boat for about 1/2 of what it would be worth with a good engine.

So, diagnosing the problems with a marine engine can be tricky . . . and remanufactured engines can be no better, because you don't know what they have been through. All you know is that they had a problem that was serious enough to require replacement. It is sometimes questionable if those problems got fixed during a remanufacturing process. Then there is the issue of the parts brought over from the original engine (usually intake and exhaust manifolds as you mentioned).

I think your best bet right now is to stop pouring money into it and see if you can get some additional input/opinions at no/low cost (like friends, colleagues, etc. that have some expertise.)

Oh, I might add . . . and this is seldom done . . . but a pressure testing of the cooling system can reveal a lot about where the water is coming from. So, that might be something to do.

 

[mr 88]

Re: 4.3 Marine Aftermarket School of hard knocks

Might want to post this in the Mercruiser forum.

 

[Howard Sterndrive]

Re: 4.3 Marine Aftermarket School of hard knocks

Her's the rub - the dispstick is now showing a quart high on the stick. it is clean looking oil so far but I am beside myself. WTF.

drain one quart out and go boating. If the oil isn't milky or foaming chocolate milk out the breather when it's running, there's no water in it. no cracked block.

my dipstick can show a quart high or low just by the trailer jack. after a run the oil shows about 5 quarts high until I wipe the stick and reinsert it.

aftermarket 4.3? I don't think China is quite there yet. The GLM Manifolds, yes, but the engine is all genuine GM.

 

[Maxz695]

Re: 4.3 Marine Aftermarket School of hard knocks

This is true that the level of the boat can make the oil appear more or less full at different angles , but this does not explaing the pinging (Possible Preignition due to A) bad timing B) poor gas octane C) thined oil (posible water) seeping buy the rings and mixing with the gas. You can A) check the timing B) Put booster in the fuel C) change the oil and filter or You can take your chances up to you. I don,t know how long the engine ran with the improper riser gaskets but any water that got into the oil however minimal could thined the oil enough to be causing this

 

[Chris1956]

Re: 4.3 Marine Aftermarket School of hard knocks

The two piece manifolds can leak water into the manifold, if the gaskets go bad or the bolts get loose. I had that happen when I was using those green paper gaskets that are standard with aftermarket manifolds/risers. I ened up taking off the mannys and risers and truing up the joints on a piece of plate glass and a piece of emery paper. I then used the Mercruiser silver gaskets which seal real well.

Since water will sink to the bottom of the oil pan, you might set the boat level and remove the drain plug and see what comes out.

 

[Bondo]

Re: 4.3 Marine Aftermarket School of hard knocks

Hi guys,

This is a very sad day for me today as my boat engine saga continues.

Here's the skinny:

I had purchased a new aftermarket replacement 4.3 motor that ran perfect all last year until the end of the year when we found water in the engine and ASSumed we cracked the block and or blew a head gasket, possible from a lean condition backfire, etc...after flooding during hurricane... Unfortunately my boat guy and I never diagnosed the source of the water because instead we lucked out and got a free replacement block sent under warrantee.

I had the same guys set up the new block with all the old parts and I opted to go with the existing exhaust as they appeared perfect having been a mere 5 years old in freshwater only, northern, low hours, GLM 3", and I was very clear that they should be inspected before putting them on. I said if there are any signs of problems of course let me know because we can't screw up this block. He agreed they were probably fine and said they looked good after "inspection".

Turns out the exhaust were put back on and but they had never separated the exhaust where the previous boatyard had used the WRONG GASKETS for the type of thermostat housing apparently. They were closed instead of open...(?) I had changed over from the one piece mercruiser to the GLM two-peice cast iron to avoid problems, OMG. WHat a complete nightmare this all is for me and my family. I am leaving out a lot of drama and saga trust me.. All summer without a boat etc...

Never would have known anything was going on as the boat was running perfect again when I finally got it back except at WOT where it would ping ever so slightly. Actually my buddies said they couldn't even hear it... SO I brought it back and now they said it was running 50 deg F hot on one side (opposite from temp send of course) and that that may have been why it was pinging... So I agreed they should change that and since then voila water is flowing properly now and cooling both sides correctly.

Her's the rub - the dispstick is now showing a quart high on the stick. it is clean looking oil so far but I am beside myself. WTF. I am test driving it on SUnday and hoping for the best but please help me clarify the scenarios so I might sleep a little better tonight.

So worst case is that I now have a brand new motor with a freshly (2 weeks ago) cracked block, or a blown head gasket, or then what else could it be risers, or exhaust manifolds correct?? I need help here as I am only a beginner still although learning the hard way... What do ya think? Please try to include some best case scenarios along with worst as that might be good for me until SUnday when I will run it hard and pull the oil.

One thing I noticed is the dipstick is below the alternator arm and looks out of place like maybe it should be more upright and above that arm maybe and somehow it is now giving odd readings because the stick is not stock and set up correctly... It has an added adapter on the bottom from a crossthreading done by previous $80/hour boatyard. I am sure this is very wishful thinking probably but has anyone ever seen that scenario?

When running on muffs it was just 50 hot so probably only like 240 Deg F although under load it may have been hotter...
What are the likely scenarios and chances I won't be screwed and boatless for a long time. Please give me your ideas thoughts and advice as i try to get through this AND still take care of my childrens needs for food etc. I want to laugh but it is hard. Thank you! I really appreciate the advice here.

Ayuh,.... On the Rub,... Is it makin' oil, while runnin', or after ya shut it off, 'n leave it for a week,..??

Was the oil level Right when ya started,..??

Drain off a quart, from the bottom,...
If there's water in there, That's where it'll be,... the 1st thing headin' for the Bearings...

When ya discovered the "Wrong Gasket" thing,... Was there rust streaks through the exhaust passages of the manifold,..??

Was the gasket surfaces of the mating surfaces checked for flatness with a straight edge,..??

 

[iskiglass]

Re: 4.3 Mercruiser with possible water intrusion

Re: 4.3 Mercruiser with possible water intrusion

Ayuh,.... On the Rub,... Is it makin' oil, while runnin', or after ya shut it off, 'n leave it for a week,..??

Not sure on this see below

Was the oil level Right when ya started,..??

It was dead nuts on the full line in boatyard and just over full after first ten minutes... but now I was checking on the water so not sure if just the different angle.. Time went by and it got higher but it was also run more by the boatyard again and time went by. Now way higher and a Full Quart high. If I were to guess I might think when it was sitting but could not be sure

Drain off a quart, from the bottom,...
If there's water in there, That's where it'll be,... the 1st thing headin' for the Bearings...

Can I get decent results pumping it out from the dipstick b/c I have a nice pump to pull some or all of it out through that which would be a lot easier for me because it is a tight compartment. Then I could open the plug to get the balance fully drained

When ya discovered the "Wrong Gasket" thing,... Was there rust streaks through the exhaust passages of the manifold,..??

Was the gasket surfaces of the mating surfaces checked for flatness with a straight edge,..??

All excellent questions that I would expect my boat guy knows the answer to you'd think.. If he saw a tell like that I would expect he would've offered me the info without me having to ask but thanks for all the great feedback Bond-O & Co.

 

[iskiglass]

Re: 4.3 Marine Aftermarket School of hard knocks

You say the oil is higher than it originally was before this occoured? I realize you say it looks clean. You also say it runs cool now like it,s supposed to. The wrong gaskets where on there that may have let some water into the oil. I would suggest that before you do your sunday was it run to change the oil and then re inspect it when you come in and see if the level has increased. If so then I would think there is definitly a problem. EDIT If you want to be dumb and risk all the work and money you spent on your engine which is according to you PINGING!!!! (Water ihn the oil) for the sake of $15 dollars worth of fresh oil, clean oil to lubricate the engine then you get what you have coming. At the very least even if it is still getting water there may be enough new oil to keep the engine going without seizing up. Not being mean here I,m trying to talk some sense into you. My thinking here is you say risers meaning V6 V8? anyway I,m sure your not running a fresh water cooling system and you have salt water in your oil in which hopefully to this point hasn,t done any or much damage to the internels from running it until pinging occured with salt water in the oil through the exhaust and into your crankcase! Drain the OIL!!! Save your engine!!! or pay the piper!

I will follow your advice here... but if i pull a quart from the dipstick and it is all clean then what? Do I bother to pull it all...and thanks for your thoughts. this is fresh water only luckily

 

[iskiglass]

Re: 4.3 Marine Aftermarket School of hard knocks

It is tough to say what the best course of action is at this point. I think the chances are slim to none that you will get out of this easily.

I assume that you have been getting re-manufactured long blocks as your replacement engines. The problem is that they can be a roll-of-the-dice in terms of their longevity. Then the questions arise about the skills of the mechanics that you have working on the engine.

I went through a process myself over the past year where I was having trouble with my engine. I figured it was the manifolds . . . I rebuilt the top-end of the engine (cylinder heads) and replaced the manifolds and elbows. I got about 6 hours on the engine after the re-build and the thing hydro-locked and destroyed itself. :facepalm:

It turned out that the cylinder heads were rusting through around the valve guides and that was the problem to begin with. I ended up selling the boat for about 1/2 of what it would be worth with a good engine.

So, diagnosing the problems with a marine engine can be tricky . . . and remanufactured engines can be no better, because you don't know what they have been through. All you know is that they had a problem that was serious enough to require replacement. It is sometimes questionable if those problems got fixed during a remanufacturing process. Then there is the issue of the parts brought over from the original engine (usually intake and exhaust manifolds as you mentioned).

I think your best bet right now is to stop pouring money into it and see if you can get some additional input/opinions at no/low cost (like friends, colleagues, etc. that have some expertise.)

Oh, I might add . . . and this is seldom done . . . but a pressure testing of the cooling system can reveal a lot about where the water is coming from. So, that might be something to do.

You are spot on and once there are problems the mechanic can keep pointing to the fact you bought it on your own and therefore you may easily get screwed..

 

[Bondo]

Re: 4.3 Marine Aftermarket School of hard knocks

I will follow your advice here... but if i pull a quart from the dipstick and it is all clean then what? Do I bother to pull it all...and thanks for your thoughts. this is fresh water only luckily

Ayuh,... If the level is Risin',... Something is contaminating it...

It's either Water, or Gasoline...

 

[NHGuy]

Re: 4.3 Marine Aftermarket School of hard knocks

see next post

 

[NHGuy]

Re: 4.3 Marine Aftermarket School of hard knocks

If the oil level is high and not milky you may have gas getting into the oil. This is repairable, usually with a fuel pump. Smell the oil. If it smells like gas, that's your prompt. Folks who know more than me will be along shortly to confirm or deny this, but it's a possibility.
Carburetors can leak too, but not that much in my experience.
If the oil gets milky you have water in there and it's time to pressurize the cooling system to find where it's getting in.

As a "quick start" set the engine perfectly level, pull out a quart of oil and put it in a clear container to see if anything separates out. Not a great test, but it could tell you something.
Of course if it's milkshake don't bother with that, just start pressure testing.

 

[04fxdwgi]

Re: 4.3 Marine Aftermarket School of hard knocks

One other cause of "the pinging" that wasn't mentioned may be a vacuum leak on the intake manifold, between the carb and intake valves. Seen it too many times when some "mechanic" used silicone form a gasket on the intake gaskets or didn't get the gasket seated properly. Fuel will disolve the the silicone sealant and cause a vacuum leak. Just a thought.... The "ping" does all kinds of bad things to the engine.

Must say, though, it sounds like you have multiple problems: 1. Leaking exhaust manifold, 2. oil level increasing, 3. pre-ignition. May all be related, may not be....

 

[iskiglass]

Re: 4.3 Marine Aftermarket School of hard knocks

One other cause of "the pinging" that wasn't mentioned may be a vacuum leak on the intake manifold, between the carb and intake valves. Seen it too many times when some "mechanic" used silicone form a gasket on the intake gaskets or didn't get the gasket seated properly. Fuel will disolve the the silicone sealant and cause a vacuum leak. Just a thought.... The "ping" does all kinds of bad things to the engine.

Must say, though, it sounds like you have multiple problems: 1. Leaking exhaust manifold, 2. oil level increasing, 3. pre-ignition. May all be related, may not be....

What about these possibilities:

1 the 4 BL Edelbrock carb was also just rebuilt by a different local mechanic. Could this have been done improperly or the replacement parts were not the same causing the WOT pinging?

2. Could the fact that before the gaskets were changed and it was running hot on one side of the engine do to lack of water flow cause this very slight ping at WOT?

The gas tank has been run to empty and have added regular gas with a generous dose of starbright enzyme treatment. Should I try higher octane gas? How high? Been using 87 regular like I always used to with no problems. I could show up with a 5 gallon tank of each if that makes sense. The tank is pretty low now having only a couple of gallons in it left.

Please critique my plan for today:

First I'll pump a quart of oil from dipstick and see how the oil looks and smells.

if it is milky I'll pump it all out and probably even get the drain plug out to get the most out possible, refill with the specified capacity for that motor and then do the the trial run.

If there is a gas smell I will plan on a new gas pump but again I will pull all the oil and fill it back up.

If the oil checks out or is milky it will be replaced and I am planning on a test drive to see if it is still making oil. I will keep checking the oil level and will try WOT again and listen for the very faint pinging over the loudness of the engine and 45 MPH wind that comes with it. Again my buddies both say they don't hear it and it did not happen on the muffs. How many times do you think going to WOT with the slight ping will cause damage? I might add the higher octane after the first run with regular gas and try it one more time.

How long does it take to burn the fuel in the fuel line before the higher octane could be expected to be reaching the carb? I will go below WOT while burning up that of course..

And is there a simple way to test for a vacum leak on the intake manifold like you mentioned? They are a fairly respectable boatyard, granted they have apprentices too, but I am sure they used the proper gaskets. Not sure they seated them properly so you never know...Thanks for all the input it is greatly appreciated

 

[04fxdwgi]

Re: 4.3 Marine Aftermarket School of hard knocks

Don't forget, you'll probably never get any ping on muffs because the engine is under no load, unless of course, your timing is way too far advanced, and then she'll probably not want to start / turn over to begin with.