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Discussion Starter #1
I'm hoping some of the more experienced can give a bit of advice here-
18' 78 Biesmeyer hull with Berkley JG & warmed over 454. It's been sitting up for several years.

Long story short- I'm running an electric fuel pump- my 750 double pumper float got stuck while sitting around and pumped enough fuel into the intake that when I went to crank it it hydraulic'ed. It turned over about half a revolution and stopped- I thought "great, the battery is going dead" so I hit the starter a few more times before it dawned on me what had happened. Pulled the plugs, blew er' out good and worked on the carb and got it cranked it back up. Didn't run it hard- it still had carb. problems so all I did was get it back to the trailer. Seemed to be ok other than the carb trouble.

My question is: how often on a BBC will having this happen hurt the rotating assembly? - i.e. bend a rod, etc. I know on certain engines, the starter has enough ass to just totally bend a rod. I know it depends on how much gets in the chamber, and a host of other factors- I'm just trying to decide whether to just run the thing, or if I ought to tear into it to check it out.
 

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Engine junkie
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Run a compression test on the suspect cylinder, or all the cylinders for that matter. If you bent a rod it will show up with a low to no compression reading.
Generally speaking however the starter won't "usually" usually bend a rod with a fuel packed cylinder, but it can and does happen so rule out nothing.
 

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JRPM/e-PerformanceMarine
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Last season at Long Beach in a heat of Comp Jet racing my 429 took a full gulp of salt water from a roost in a warm up lap. I was only turning about 4500rpms. It kill the engine instantly, I was somehow able to just bump the starter to bleed off the water, it seemed like it took forever and refired it before we were run over by the boats that took the green. The engine was fine for the rest of the season and the begining of this season with no problems up untill I sunk the boat on April 17th. Now I had a stock 429 crank and Eagle SRI rods. I feel I was very lucky to have had 0 problems with that engine. But gas in oil is very bad. I will let you know how the rods check out after I get the boat back and we tear the engine down and do a full inspection on it.
 

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Living in a cage of fear
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In my experience it isn't exactly the starter that will do it. If the engine fires for a split second with water in a cylinder then it can easily bend rods and break a chunk right out of the block and heads.

So being flooded out with raw fuel sort of saves it, since it probably wont fire.
It is far more damaging to have water in a few cylinders and have another cylinder fire one time. I can vouch for that personally!

Compression check will tell the tale, but having it start and run is a VERY good sign!
 

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Boat Nut
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Real trouble happens when just one cylinder fills, and the other are empty, and the crank gets a good swing.....this is when the rods gonna bend. If they all fill, chances are the starter won't be able to turn the crank.
 

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Discussion Starter #6
Hydraulic?

It had fuel in several cylinders when I pulled the plugs and blew it out- lots of gas- I used two towels and a roll of bounty trying to make it safe to crank again- nothing like floating around trying not to get swamped- with a bilge full of raw gas. I don't know if any cylinders fired or not when I first tried to crank it. I gotta do something with the fuel/pump/electronics to keep that from happening again.
Maybe I am ok. I'll do the compression check for sure. If I wanted to check further, would pulling the heads and looking at piston top to deck measurement be a tell-tale? I know there would be some variance as the deck would not be perfect, but it may show up a problem?
 

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Living in a cage of fear
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Do you have a fuel pressure regulator?
 

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It had fuel in several cylinders when I pulled the plugs and blew it out- lots of gas- I used two towels and a roll of bounty trying to make it safe to crank again- nothing like floating around trying not to get swamped- with a bilge full of raw gas. I don't know if any cylinders fired or not when I first tried to crank it. I gotta do something with the fuel/pump/electronics to keep that from happening again.
Maybe I am ok. I'll do the compression check for sure. If I wanted to check further, would pulling the heads and looking at piston top to deck measurement be a tell-tale? I know there would be some variance as the deck would not be perfect, but it may show up a problem?
Although not impossible, its unlikly you will have bent a rod on that big motor simply attempting to crank it , We had this happen , we simply pull the plugs ,purge the cylinders and change the oil and remedy the fuel issues . The majority of hydrostatic locks we see (my ins inpection businesss) are rain or off road related from for example a vehicle "blasting thru a puddle" while running , or more commonly trucks fording the rivlets at the beachs, I've inspected Toyotas with both sides of the engine blocks blown out rods broken in half etc . The most common minor symtom might be a slight "jiggle"/ vibration at idle and low "dynamic" compression (needs a cylinder balance test to isolate) Cranking compression alone may be comprehensive . More info and tech help if you need it feel free to call :)coffee Tom
 

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putting a low oil pressure cut out switch to prevent the pump from running when just the ignition is on works to solve that problem in the future and adds some other safety factors in.
 

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Discussion Starter #10
Yeah- I have a fuel pressure regulator. I got two Holly Red pumps- a primary and a backup- plumbed into the system. Only one runs at a time. The regulator is set at about 7-8 psi. I have the pumps wired to separate fused/switched circuits independent of the ignition. I dunno why I did it that way now. I had a lot of trouble a few years back when I first put the boat together with trash in the tanks- and I did a lot of tank flushing, and circulating trying to clear them out. Spent lots of time messing with just the fuel system- so I had it on a separate circuit. Ended up replacing the tanks with new. I got multiple filters and a water separator- I suspect just old fuel varnished and stuck the float.
 

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Discussion Starter #11
Oil pressure switch-

I understand a safeguard with low oil pressure like that is on most all fuel injected cars. Also, many of them must see fuel pressure to enable spark.
My only issue is how to fire it off after it sits up for an extended period and the fuel bowls get dry? I guess I could pour them full manually, squirt raw gas down the carb, or wire in a hard switch to the pump to prime the system. How would this normally be handled on a boat like this?
 

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What the Hell is That?
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Personally I would ditch the two Fuel pumps. I have been running the holly Blue forever and have never had a problem with it cutting out or dieing. The only thing there not good at is Sucking. Also you might want to turn down the PSI to say 6 or 6 1/2 most Carbs don't like a whole lot of PSI.
 

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I understand a safeguard with low oil pressure like that is on most all fuel injected cars. Also, many of them must see fuel pressure to enable spark.
My only issue is how to fire it off after it sits up for an extended period and the fuel bowls get dry? I guess I could pour them full manually, squirt raw gas down the carb, or wire in a hard switch to the pump to prime the system. How would this normally be handled on a boat like this?

I use a relay for the pump and put the low pressure switch in there somewhere as I can't remember if it was a ground deal or + side situation. but I just jump the relay to prime the bowls. I keep promising myself to put in a push button switch, but never have gotten around to it yet. :D
 

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Discussion Starter #14
Fuel pumps-

The second fuel pump is just a backup- I can throw a ball valve & hit a
switch and be back in business if my primary ever fails on the water. May be a bit anal, but I have had fuel pumps fail before. I may lower the fuel pressure a tad. Biggest thing is just put new needles and seats in the carb- :)
 
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