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You BLOT that schit!
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Discussion Starter · #1 · (Edited)
Problems.......

New manifolds put on a motor I got to temporarily replace one that dropped a valve and subsequently cracked the block.

Oil cooler was leaking water into the bilge after the install, looked like a pin hole maybe, nothing major.
I ran for about 40 minutes, ended up with 1.5" of milkshake in the pan.
Where to look first? Could a cooler that is leaking (externally) be a sign of one that is failing and allowing water into the oil? Water pressure was pegged, over 35 psi, I wasn't thinking much of that either until I check the oil tonight.

Sucks to be me, 20 hours (total, two men) of engine swap last week, got one ride out of it before this.......

No reason for me to suspect intake gasket, and, as I said, the manifolds were brand new out of the box, existing stainless risers were used with new gaskets of course.



HELP! :(
 

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Horsepower Junkie
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Phil, I would look hard at your manifolds and risers. I have a pressure checking rig if you would like to use it. I would bet that the same thing that caused you to eat a valve in the original engine is the same thing that is causing the milkshake in this one. I would doubt the oil cooler would leak water into the oil, the oil pressure should be higher than water pressure.

Frank
 

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You BLOT that schit!
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Discussion Starter · #3 · (Edited)
Frank,

Can that be checked in the boat or would the manifolds need pulled (dumb question?)

I'm also inclined to look hard at the manifolds/risers. Remember, I got new manifold as a preventive measure not even trying to guess if my original ones (to the old motor). Think is, I never had ANY water in the oil on the old motor, up until and including when I climbed into the bilge when it shut down and died. Oil was clean as can be, not a drop over filled.

I still haven't retrieved my tools from up at the shop where we swapped the engines. I need to run up there first thing in the morning with the trailer to even be able to pull spark plugs to check for water there........

Oil pressure stayed above 55 psi, even at idle, ran up to around 75 or so. As I said, the water pressure was pegged over 35.
 

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You BLOT that schit!
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Discussion Starter · #4 ·
Risers where a bi'atch to get lined up, actually spent over an hour screwing with the back two bolts on both sides. All the bolts were TIGHT when I got done.

Interesting note, the riser gaskets that came with the new manifolds were different than the ones on the old set. There was only a steam hole on the one side(s), regular slots on the other side. I saw this as fine considering the risers that are on the boat don't even HAVE front and back holes, just the sides are open (front and back are smooth, solid stainless).
 

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Horsepower Junkie
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You can check them on the boat, but you will just have to stick your ear to the tail pipe to see if you can hear anything.
I would be more concerned with the water pressure issue. Over 35+psi can easily cause an intake gasket to leak. There has to be some kind of cause for that excessive of a pressure.
 

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You BLOT that schit!
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Discussion Starter · #6 ·
64LS1Nova said:
You can check them on the boat, but you will just have to stick your ear to the tail pipe to see if you can hear anything.
I would be more concerned with the water pressure issue. Over 35+psi can easily cause an intake gasket to leak. There has to be some kind of cause for that excessive of a pressure.
Hmmmm.

We were having a hard time getting the hose clamp at the outlet side of the pump to seal up too. Tightened it three different times, it was still leaking (slightly) when I came back in last night.

New impeller was installed while it was still on the stand.

What could cause the excessive pressure situation?
 

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Horsepower Junkie
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No. It has some kind of restriction somewhere to cause the pressure to be that high.

Gimme a ring on my cell phone if you have that #
 

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You BLOT that schit!
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Discussion Starter · #8 ·
64LS1Nova said:
No. It has some kind of restriction somewhere to cause the pressure to be that high.

Gimme a ring on my cell phone if you have that #
Don't, I just have the home number.


Can you e-mail it to me?
 

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You BLOT that schit!
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Discussion Starter · #9 ·
I don't think this should be tied together, but I was really concerned at the LACK of water I was getting out of the exhaust, particularly on the outboard side when running on the hose before I drug it down to the ramp.
It flowed much better when we ran it up over idle, but was just barely coming out of that one side most of the time.
 

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Discussion Starter · #10 ·
Thanks a lot Frank, you really gave me some good ideas as to where to start.

Hopefully I can get this nailed down tomorrow.
 

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Discussion Starter · #11 ·
Short version of the conversation is (for the sake of the thread and future searchers).

I am going to look for a restriction at the manifold/riser. Thinking along the lines that all my concerns about
1) Lack of decent water flow at one side of exhaust while running on hose.
2) Excessive water pressure readings while running (over 35 psi)
3) Inability to get outlet side of raw water pump to stop leaking (pointing towards a restriction down the line somewhere).

All of this leading to a blown intake gasket. (maybe?)


Ah,... the joys of boat ownership. I probably have 40-50 hours of messing around with this boat and KNOW I have a total of 9 running hours on the clock so far this season. :rolleyes:
 

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How do you know you have 1.5" of milkshake in the pan? First order of business is to get that out using kerosine, spinning the oil pump with a priming tool. Then clean oil and spin with the tool. Then start troubleshooting.

Is it possible an exhaust valve is set to tight and not closing all the way? That would suck in a lot of water fast. You should also pull the plugs and see which ones are wet. If it is the center plugs its likely an exhaust manifold leak.
 

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Discussion Starter · #13 ·
Blue Thunder said:
How do you know you have 1.5" of milkshake in the pan? First order of business is to get that out using kerosine, spinning the oil pump with a priming tool. Then clean oil and spin with the tool. Then start troubleshooting.

Is it possible an exhaust valve is set to tight and not closing all the way? That would suck in a lot of water fast. You should also pull the plugs and see which ones are wet. If it is the center plugs its likely an exhaust manifold leak.
I am just reading the dipstick and estimating the amount of intrusion. (new oil and filter change on Thursday night) is reading way over-full and not clear or golden at all, more like white colored. I will be changing the oil again before I mess with it. We ran the boat for a while on the hose before launching it, oil looked nice and new up until we ran it on the water.

I am going to pull plugs tomorrow morning, first thing. Thing to consider is that nothing was messed with internally on the engine, only "new" things introduced were the manifolds/risers and basic accessories. (kind of doubting head issues).
 

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Bypass the cooler and run it on the hose on the trailer and see if it does it again
 

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Discussion Starter · #16 · (Edited)
obnoxus said:
Bypass the cooler and run it on the hose on the trailer and see if it does it again
Well, I have another cooler I can swap it with, kind of a pita, it's a different length, would have to swap compression fittings and all.

I was steering away from that thinking the oil pressure would be greater than the water pressure at all times (not allowing it to get in that way?).

So far there is no exhaust reversion, plugs look fine, not water in the cylinders.

Both hoses to the manifolds/risers flow even and well.

Moving on to checking the thermostat housing itself for some obstruction.

I will probably just swap the cooler so I can get a chance to call it good (or bad) in the garage with air. REALLY would like to know what I have going on here before I take the intake off.

The water pressure pegging has me concerned, would love to find some obvious reason why this is happening now.
 

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have you had an impeller failure in the past? as a certified marine tech i can give some insight as to many over heat issues. #1 is blockage in the water flow. most are caused by impeller parts blocking water flow. to cure this all you need to do is disconnect the water intake hose from the the oil cooler and supply, go upstream to t-stat or heat exchanger and back flush with a garden hose. look for rubber parts or other parts. you can also check water flow at any hose going to the exhaust by removing it while engine is running at idle. water flow should be steady and a large volume( it is only at 2 to 3 psi at idle) volume is the key lack of flow results in high engine temps.
hope this helps
 

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You BLOT that schit!
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Discussion Starter · #18 ·
I pulled the oil cooler (fun) just for good measure. Have the other one ready to go in now. I noticed while looking in the t-stat housing that it has a 140* thermostat. Odd thing is, I was running closer to 160-170 most of the run.
The impeller is brand new, the one that was taken out was totally intact, a little dry around base of the blades, but nothing missing at all. I didn't have an "over-heat" issue per se', new alarm never screamed on me, gauge never read over 170 or so. Just the PRESSURE that was odd to me.

I got a cheapo external gauge to hook up temporarily to have a friend watch while running (second opinion to my dash gauges). Since I've all but ruled out reversion or manifold/riser leaks, all I have left is this pressure issue that must have blown the intake gasket...........

I hate boats.
 

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You BLOT that schit!
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Discussion Starter · #19 ·
Can a sticking thermostat allow pressure to build on the block? I assumed it just wouldn't open (enter), then over heat......?
 

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Not really. It can create steam and non cooled areas of the block. But not high (liquid) coolant pressure. I would drill some holes in the tstat though to allow the release of air from the engine coolant system at startup.
 
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