OMC 5.7 acceleration problem - pics included

Maclin

Admiral
Joined
May 27, 2007
Messages
6,761
Re: OMC 5.7 acceleration problem - pics included

I am pulling for you, that was just a lot of stuff to change all at once :eek:!

OMC's and Volvos do power the fuel pump from the alternator. I am not sure about the electric choke though, that sounds like too much for that circuit.

You may need to think about powering the fuel pump the "Merc" way, which is a good 12v source with proper gauge wiring thru an oil pressure safety switch. You could probably get more dependable current that way.

I think I would definitely get the choke wired differently after your explanation of the "results".

Good luck!
 

Crapduster

Seaman Apprentice
Joined
Jan 26, 2008
Messages
40
Re: OMC 5.7 acceleration problem - Work in progress update 12/20/2009

Re: OMC 5.7 acceleration problem - Work in progress update 12/20/2009

Been busy last few weeks at work and January is not going to be too pleasant with deploys in the northeast all month. I did manage to get some work done on the boat. For starters, to the fella' that put the oil filter on my boat last, it don't take 100lbs torque there King Kong. 35 minutes to get an oil filter off... finally had to use the old screwdriver through the filter trick. I have these really thick water repelling oil/solvent-absorbing sheets that I keep around and I had 3 of those and it kept the bilge spotless when I punctured the filter. They were a bit pricey at West Marine, but I knew they would come in handy.

I finally broke down and got a few things I have been sorely needing. A decent advanced timing light w/tach and a multimeter from Sears, and a quality test light with a screwdriver handle and sharp end for piercing wires to test for presence of voltage. $170 for all. I like Sears. Now I can also finely time my two stroke Suzuki properly. :D

Bought a quality inline fuel screen from a local hotrod shop. It is not a filter, it screws apart and seals with an o-ring. Nicely machined aluminum unit. It has a pleated metal screen inside to catch the larger stuff pre-pump. After the pump it goes to the regular screw-on fuel/water filter/separator. Also replaced coil with a basic stock replacement. The old coil is fine I believe, but was the original from 19 years ago, had dents in the outer layer from over-tightening the clamp that holds it and the new one was $10. This is the exact model I got: http://www.amazon.com/ACCEL-8140-Performance-Universal-SuperStock/dp/B00064P99W ...at $10 brand new on Craigslist, had to do it. So I have a new coil now, and the Holley recommended type of screen between the tank and pump. I also got the bilge blower working perfect, smooth and quiet. I found out the 1500GPH bilge pump runs just fine, so a wiring problem somewhere between the dash switch and pump exists. Will get that fixed this week. After I pulled out all that radio wiring, the horn stopped working. Gotta get that working for sure before going out. Wired the electric choke to the charging output on the alternator as suggested by a buddy. Plenty of juice for the choke and only on when the engine is running. Also, have a new 4blade SS prop that I will test out hopefully sometime Thur-Sun this week.

In 4-5 days I will post some pics of all this engine bay stuff going on and the prop and such and report back on if everything is running right. I believe I have the engine and major electrical gremlins worked out now, but running it around the lake for a few hours should shake out any unknown issues.

I filled the boat up with gas today, while doing so I noticed that air/fumes were flowing from the vent holes next to the gas tank nice and steady as I expected. When I accidentally over-filled the tank, gas poured out of the vent holes briefly... can I take it that this confirms that the vent to the fuel tank is not clogged? Is that a one way valve of some sort?
 
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