Bo0rke down just in time for Labor day...
 

Went out tonight did some swimming hanging out etc. Went to leave, as always I started the boats and climbed up front to pull the anchor, as I was doing this the engine died, which isn't normal at a 1200rpm high idle :(. Initially I though my kids pulled the lanyard or something, but it sputtered out. I knew I had spark since the engine was trying but only if I really pumped the gas and eventually had nothing once the diaphragm in the fuel pump bled down all the way. Held onto the fuel pump (electric) and felt nothing, $hit. Followed the power wire to the port side bellhousing area where it plugs into some type of sensor/terminal with three connections, I assume this is the trigger for the fuel pump that senses the engine turning and kicks the fuel pump on??? I took the lead from the the fuel pump that was connected to this and grabbed the closest power, the distributor hot, and touched them together and voila, fuel pump kicked right on.

I was with my family so I didn't have to much time as it was getting dark so I cut the wire near the pump and hard wired the pump to the starter solenoid to get back in and ran the 12 miles back and disconnected it.

This started life as an OMC 502 package that i've pretty much deleted anything OMC related, ignition etc. I put a new fuel pump on last year, and based on the ride back in it's definitely good. It's a carbed motor so it's a low pressure pump.

1) What is the "sensor" or terminal the power is connected to on the port side rear near the bell housing? Could that be it?
2) I didn't get to check the relay or anything since it was dark when I got back just in time to have it pulled out for the night, but is there anything else I should look at??
3) I did push all the breakers and that did nothing.

If this ruins my weekend plans I may have to lose it :( Seems like this should be an easy fix, but you know how that goes.

As always any help or insight would be appreciated!!!!

I've had a similar issue to you. I'm not sure how you are setup but mine runs off of a relay that is wired to the oil pressure switch. It also has an inline fuse between the relay and the pump. Mine started blowing the fuse to the point I couldn't even idle in. Mine ended as a bad pump that would run if jumped over but was drawing to much for the fuse. It's gotta be something simple such as the trigger you mentioned that I would guess senses oil pressure and allows the pump to run. I know you said you checked breakers but give it another look and see if there is a fuse wired into the pump as well somewhere back there. Remember to keep it simple.

The 'sensor' you are talking about should be a Hobbs switch, should have a common, NO and NC. It's so your fuel pump doesn't keep running when the engine dies, it should be in an oil passage and when the oil pressure builds it completes the circuit to your fuel pump.

Thanks guys, I know I had good oil pressure on the ride back in so I'll start there with the sensor and this time I'll have more than a few minutes and I'll be armed with actual diagnostic tools...which usually helps. Hopefully I can figure it out quick, the marina would laugh their a$$ off if they see my hack job using first aid kit tape to hold my wiring together, but when you don't feel like getting stuck in the dark with a 4 year old and 1 year old waiting for tow-boat us, it's amazing how quickly you can Macgyver something together. If only i'd figured out how to incorporate some gum, it would have been official "Macgyvering" :)

At least several people at the place we were hanging out stopped to see if we needed help, boating people are generally good people.

Not saying now beings the weekend is coming up but down the road you ought to concider taking off all the electric pump crap and go to a mechanical pump.

Gen V block, that ain't happenin'

Sure ya can. Switch to the sea water/fuel pump design. That's what merc did when they switched to the gen 5's. Used these from '92 to '99. If you watch around you can find them used for around $200, sometimes less.
Here's what they look like:
http://www.ebay.com/itm/NEW-Mercruis...21e98b&vxp=mtr
Just say'n, electric fuel pumps suck. Best to stay away from them if you can. I quess it had that because it started as an OMC.

Interesting, I didn't know that. As you state, if OMC did it, it was probably a bad idea :)

And I'm with you on the electric pump thing, just didn't know that was an option.

BBC, there have been a few posts out there complaining about the mechanical pumps mounted on the seawater pump. There is an oil reservoir that has to be changed regularly, per the Merc manuals, but no plug to drain it. A lot of guys installed their own drain plug to help with this. Another bad thing about this design is the fact that if the fuel pump diaphragm fails (and it probably will), the reservoir gets filled up with gas. I think a few guys have managed to adapt a better aftermarket fuel pump to use the Merc actuator arm so that they could be installed on this system. Do a search and you will find the thread.

I would start by jumping the oil pressure switch to see if it sends power to the pump. That would probably isolate that as the problem. You could also run a DVM across the leads on the switch and have someone spin the motor over to test it.

I carry a spare pump on board with me for such an emergency. Standing on your head in the bilge beats paying for a tow back. Keep plenty of rags on board too to mop up any spilled fuel. I also keep an electrical kit with crimpers, pliers and solderless terminals. My boat might pick up 3 mph if it weren't for all the crap I have stored on board!

Got it fixed, boaters value in wyandotte pulled the part out of an aftermarket fuel pump kit and sold it to me for $20, it's installed and fixed my wiring from last night, all is well. Last night I put together a better tool kit...it's on the boat now :)

What component ended up being bad?

Glad to hear your back on the water for Labor Day!:party-smiley-020:

Oil pressure safety switch, just like this one, just you guys suggested! Once I had my test light there I could tell there was power getting to the one side of the switch and not the other, so that made is pretty damn easy once I had a test light. Though in hindsight I should have just pulled the hot wire coming in and connected that to the fuel pump to bypass the switch instead of cutting the pump wire. It's funny how you make pretty dumb decision when you are under pressure...(wife getting nervous etc.) At least it's soldered and shrink wrapped now not using crimp connectors, which I hate.

http://www.summitracing.com/search/B.../?autoview=SKU

My fountain has both a mechanical and electric pump. The electric pump only runs once the oil pressure is up. So there is a switch on the dash to over ride the oil presurre switch so you do not have to crank the engine a lot to get it fired up. I just hit the switch for a few seconds before a cold start this fills the carb and she always fires right up. The rest of the day it fires up without doing this and would also shut the electric pump off if there was no oil pressure.

So many combinations out there...though I swear mine doesn't turn over once before it fires the diaphragm keeps it primed unless it sits over the winter or something, then it turns over a few times, but not many.

Though this is what it looks like when tow-boat us shows up just as you finish Macgyvering...

https://www.dropbox.com/s/27ogkxpmjm0j8h5/P8290061.MP4

Here is the video I took after the fix, appreciate your help guys!

https://www.dropbox.com/s/walnix0xvk...%2008%20PM.mov

BBCLib, what exhaust are you running with that cam? Is it the same exhaust that you dyno'ed the engine with?

Stainless marine with standard risers, the engine was effectively "tuned" on Dyno headers and then the manfiolds were installed and pulled 2 runs with the exhasut wet over 20 (I don't remember 100% the exact # loss between the two) horsepower loss when we changed to the marine manifolds, so those are real world #'s. Not the best for bragging maybe, but I don't really care. The engine is worth more than the boat at this point anyhow, but it's what I could pay cash for and fits my needs.

So yes. See the pic of the engine. It would sound even better if the exhaust tips weren't 1/2 under water :)

https://www.dropbox.com/s/q2fub78lkhblq83/502.jpg

And she run's pretty good for a hull that I think everyone would agree, isn't a particularly fast hull, in fact most would call it a slow hull (including me). 4 adults and my 2 girls on board and I'd just filled up for this weekend so this is a slower # than I usually see.

https://www.dropbox.com/s/evm38ifq4km67c1/GPS.jpg

Sorry My father-in-law doesn't understand what keep the camera below the windshield means, I guess he likes hearing the wind :)
https://www.dropbox.com/s/qxdbfn6sahgw7ej/P8290035.MP4

And yes, this is about 2 hours before the oil pressure switch took a dump :)

Yeah, I know what you mean about that. I bought my Baja back in 99, and I thought for sure I would be sitting in a 30ish Formula by now. Two kids later, so much for that! I really went way over what I had planned to spend on this boat engine. I had hoped that the 461 that was in it before would have hung on for a few more years, but it had over 500 hours on it when I finally lost the ringland on a couple of pistons - detonation, most likely, or it would probably still be running. I have a stock Gen VI 454 long block sitting in the garage that I will probably throw together and put in the boat if I ever sell it.

Did you have someone fabricate those pipes going out to the side exhaust? A friend of mine has a similar setup on his 27 Nordic. He wants to put headers on it but I told him to leave the thing bone stock and enjoy it.

Those were actually on the boat when I purchased it, the previous owner intalled the SM manifolds and could never get it run correclty after that. Turned out is was the crummy OMC spitfire ignition and had nothing to do with anything else so a DUI distributor and a bunch of re-wiring later I was back in business and saw a best of just about 63mph, 61-62 anyday. I spun the #4 bearing and lost oil pressure last fall and had this built over the winter.

You already know the engine combination. I called Bob to do a basic rebuild and he basically told me if I didn't go roller I'd hate myself forever (ok so he used much nicer words than those :)), so I did and holy hell have I been happy with the results for a pretty damn basic combination.

It added about $1200 to the job, but had I not done it I still be getting embarrassed by those pesky baja's/fornula's/etc and all the other boats I wish I had... Now at least I get to at least play and on occasion DO some of the humiliating (and lets be real, getting beat by a liberator is pretty humiliating).

There is a 25 Outlaw at my marina that flat out hates me, guy won't even talk to me. He swears next year I'll never beat him again. The boats are really close in speed, I barely edge him out (502/415). I like to tell him he's lucky I always have my family with me or it wouldn't even be close :whistle:

Makes for a lot more fun, do doubt about it. The wife is starting to ask for a cruiser, so I'm not sure how much longer the fun will last. But for what this thing is actually worth if I sold it, maybe I'd just hang onto it.

What kind of increase in speed did you see after the rebuild? Was the boat running a 502 previously when you were seeing low 60's?

I know what you mean about being pushed for a cruiser. I have two daughters, so in a few years I imagine I will be hearing them whine for an enclosed head. To be honest, when I am tied off in a cove with some friends who have cruisers, the idea of all that space is appealing. But have you ever had to drive one of those damned things? It's like driving a bread truck with bad shocks. The things just lay over. I told my wife if I give in and get one, she will be doing all the driving! :eek: Another friend of mine sold his go-fast because his wife told him she would spend more time with him on the water if he got a cruiser. They had it for about two years, and she still never wanted to come out. He finally sold it and got another smaller boat. I will probably eventually cave in when I get a few years older, but then I will have to build some bodacious supercharged engine for the Camaro so I can get my HP fix from somewhere!

Links aint working for me

Sorry bout' that, I re-arranged my dropbox folder AFTER I posted, I fixed them.

I've seen a best of just under 71 with 3 passengers and about 1/2 tanks of fuel, I've never run it just by myself but I've sure I'd see about 72 if I did, I have two deep cycle batteries, and all the normal pleasure gear on the boat; tube's and rafts for the kids, porta potty, etc. The GPS picture was on the run out the day it broke, that was with 6 people on the boat. Look at the links again I fixed them. believe it or not I picked up a couple mph of speed cutting the baffles out of my tips after the build, it would fall on it's face where it didn't on the dyno, so I knew that had to be it:

https://www.dropbox.com/s/fpqgh0lk7edqp1t/tips.jpg

The boat was one of the rare OMC 502's and looked like this when I originally purchased it, rated 420hp and 385 prop horsepower stock, note that they had both batteries on the drivers side, FAIL, I moved them under the seat on the port side, where they belong...

https://www.dropbox.com/s/dmd4crc112jhqtr/OMC.jpg

It ran about 61 with the stock prop and SM manifolds, the ballistic prop picked up about 1.5 mph.

And cruisers, I know all about em, and may get to know more soon :) Luckily my wife also grew up around boats, and I'm passing that on to my girls, they LOVE it.

Hey Lib! What size boat is that? Post up the engine specs to share with us. Looks like it runs good! What ya run'n for a prop and how many rpms will it turn?

It's a 92' 221 Liberator (21'8" centerline, 23'3" LOA, 8'4"Beam), though everyone thinks it's a 201 since they look nearly identical and were WAY more common.

-Gen V 502 converted to roller (basically the cp performance conversion "kit")
-Basically stock bottom end with, crank turned .010, stock rods, stock pistons .005 off the heads and block to square everything up align honed etc.
-scorpion full roller rockers
-088 heads, no porting, but port matched with comp cams springs retainers etc.
-edelbrock air-gap intake, shaved to match the head and block decking
-850 holley with HP500 flame arrestor, down one jet size on the secondaries from stock holley 80443 marine.
-Bob Madera custom cam LOTS of lift, mild duration.
-DUI 7000 Series stand alone marine distributor, no boxes for this guy...(deleted the damn spitfire engine management system)
-Stainless Marine Manifolds with standard risers
-assembled by Detroit's best kept secret, American Engine and Machine

Turning a 21" Ballistic prop to about ~5300rpm, peak power was just under 5200, and pulled strong to 5500 on the dyno. We limited the RPM based on the stock components in the bottom end. Running through a 1.43 ratio King Cobra Cone clutch drive. And before everyone goes nuts, I know the #'s don't make sense, the Ballistic prop acts almost like a 22" prop, in fact, it's only around 50rpm different that my 22" Raker, but the Ballistic performs a little better, better hole shot AND top-end...it's almost like a labbed 22" prop, who knows, but it's good.

Basic combination, fantastic results. This thread has come a long way from my failed Oil Pressure safety switch. :)

just a note, the GM OPS(oil pressure switch) that is above the oil filter pad will tell test light 12v present. pump will run at key on, but will not flow enough current to run pump. mercruiser finally used it to run relay, will drive you crazy first time you have to fix one. good work getting it.

if you get pushed to a cruiser there are few companies out there that make some nice performance cruisers. kinda the best of both worlds.......not sure how many do 70 but i am sure they could