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electric fuel pump conversion

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ethillbilly

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I am attempting full restoration of 1967 merc 1100ss so far going well, just closed up the block, had:confused: 140 psi on all cylinders, need help deciding to change over original fuel pumps for an electric, have heard a holly red works well on these engines dont know how the return line would work from the bottom carb back to the pump, any help will be appreciated thanks
 
I have a couple of those 110 HP towers apart at the moment ----------------Not sure why you would want to go to electric pumps as the two pumps on it are very good and reliable.-----------Just need new diaphragm in most cases.
 
Thanks for the reply, I am new on these but really enjoy working on them, had some problems with rebuilding the fuel pump on an 86 mercury 50 hp the new kit came with plastic rivets and one didnt hold on the disc that acts as a valve had to go back and put in a screw. these inline six's have two pumps with more substantial looking discs and metal retainers havn't had them apart yet but im sure they work. I thought an electric would take less parasitic drag off the crankcase pressure and maybe be more reliable on idle and mid range acceleration but I'm guessing no experience. If you have any input on rebuilding the carbs (3) I have some kits on the way but havn't got the carbs apart yet. Also trying to clean and fix up distributor some but can't get rotor out easily and stopped.
 
There is a special tool ( I have it ) to remove the rotor.---------Don't break the rotor as it is pricey to get a new one.-----------Those fuel pumps and carburetors are easy to repair and very reliable.-----------Those pumps do not really affect crankcase pressure.--------An electric pump would not give you " free horsepower " so no need to do that.
 
I soak metal parts in lacquer thinner in a sealed metal paint can because it is very thorough and quick. NOTE: Store this product outdoors out of direct sunlight. It is a dangerous solvent; use only in well ventilated areas away from sources of ignition which includes wearing only cotton clothing and using only cotton wiping cloths. Synthetic cloth in all forms can and does cause electric static sparks that will ignite lacquer thinner vapours and fumes.

... can't get rotor out easily and stopped.
Click to expand...
It's probably loctited in place like Mercruiser engines. If you can't pull it off using channel lock pliers you will have to gently split it w/a hammer/chisel combo.
 
Be gentle with the rotor ----------It is usually held in place with an O-ring and has likely not been off for a while.-----------2 screwdrivers or wood sticks / wedges come to mind as improvised tools to take it off.
 
Ill try the lacquer thinner, I will probably just button the distributor back up unless there is an o-ring that should be replaced. there is two grease fittings on the main shaft above the dist. cap maybe i should just re-grease these and clean and paint it. the reason i wanted to get it apart is the trigger underneath the distributor cap has three wires white, black, brown, I wanted to solder on new ones but after cleaning them they seem flexible and not cracked. I have an original dealer service manual for this engine (e-bay) and it says loosen the screws under the distributor adapter and trigger slides out but the type I have will not allow me to reach these screws because of another plate just above them (above as the distributor is mounted upside down on the engine. all other wires are hard cracked and corroded, i have already replaced the yellow ones that come from stator and get the correct resistance reading from them, the ones on the distributor must move a little when the timing advances with throttle advance these three wires seem to use a more flexible type insulation, the cap, carbon brush and rotor button look almost new maybe i should just put it back together.
 
More questions from east tn hillbilly, continued from previous post, the rotor button has a metal disc below it all attached to main shaft with rotor button. that is why I thought the rotor shaft needed to come out from distributor adapter, the manual says do not attempt to remove rotor button from shaft must be replaced as unit.
 
Agreed on the newer assemblies the rotor is part of the shaft.---I got confused with older 2 coils and 2 inputs to the distributor cap.--Those spark distributor rotors come off with the special tool.
 
Back to the fuel pump issue for a sec. I just posted a note yesterday, from my experience with electric fuel pumps over a couple seasons, and a couple installations. I have been on another site for quite a while, but thought I'd get on this one too. Hope the info. helps -- the electric is a waaay better fuel supplier, with the proper precautions and no short cuts.

Have a great boating day, Cal
 
Agreed, but be sure to use a MARINE pump for insurance and USCG reasons. I made up a little skid for mine containing the pump, a water separator and a ressure regulator (set at 5 psi).

Jeff
 
Thanks, fastjeff -- What motor are you doing the conversion on ?? Sounds like the 5 psi. is a good place to be for most boating, I lowered it a bit for harbor cruising, trollinf, etc. but need to remember to raise pressure afterwards. I didn't see any marine pumps that looked right to use, so mine is an auto pump, as listed above.

We here in the outback don't insure every boat we have, that is for those who buy a brand name, make payments, which is most folks. All the guys in the club own a variety of hull types, all are wood and hand built, most are not insured. Out here our auto insurance covers trailered boats, as long as attached to the car, in the water it's our problem. Registration for my 18 footer is about $60. for two years, but only powered boats need register, and over 12 feet.

I will look for a marine pump, see what is offered. I like your putting it all in a tray, sounds safer. My regulator and pump assembly is on the deck with the filter mounted higher for easier changing. A plastic tray would be a good idea.


Another seasonal thing was to get a short set of the most energy efficient white Xmas tree lights, a small inverter to get power from the battery, and now I have lights under the side deck, to make safer night fishing, and way cool dockside cocktail hours after dark. The lights make camping aboard under a boat cover really fun. We have had ten aboard for sundowners at the dock.

THanks, Cal
 
Another note, the replacement diaphram on my "back up" fuel pump is not the same as the original ethanol resistant on, form last spring. Will be on the horn to Sierra about this, and to our illustrious Marine Engine people. I don't expect a problem, they have assigned a contact person to help me with finding out what and why the factory is doing, and when we can expect to get the "right stuff" for ethanol fuel. Will post as possible on this, here and as a new thread topic.


Thanks, Cal
 
thanks guys for the input, i got all the distributor stuff worked out and am still wondering the best way to go with the fuel pumps, dont mind reusing the original style but want to upgrade to electric if it will improve starting and reliability. short recap, im restoring a 1967 merc 1100 ss i believe one of the first with electronic switchbox still uses distributor but electric trigger instead of points, inline 6 with 3 carbs, will a holley red (marine grade) supply the correct fuel pressure, do i need a fuel pump selenoid (electric switch to provide correct amperage)do i need an external fuel pressure regulator, the info on the holley says it is rated at 5psi. i feel sure i can wire the pump to come on only when the ignition switch is in run position and off if safety switch is off (whitch i intend to add to the original control box. how can i make it work with an "in" and "out" on each carb, one feeding the other and the bottom carb line goes back to the fuel pump on the original set up. do i run this line back to the intake side of the pump directly or in the same place with a pressure regulator in line or just cap it off, do i still need a primer bulb thanks for reply's i think i will try to ask a holley technician these questions and will post any info i get, again this is an outboard not inboard east tn hillbilly
 
Thanks, and Merry christmas Jeff. In mails form other techs, I also put a plate over the manual pump hole so a diaphragm failure wouldn't fill the crankcase, big oops !! I'm really pleased that the people on this web site have progressive, and helpful advice to solve problems. One other just said "the factory doesn't do that, you don't need to". I think the electric makes way more HP than the old pump did - now that the pressure is correct, and has the cannister filter to (maybe) smooth the flow, and protect the system.

I always run the carbs out of gas at trips end, and have three tanks, so I spent too much time rebuilding diaphragms in the middle of trips, user error but still no fun. Now I just keep the old pump handy, in case of whatever!!

Thanks to you and the other responders, Cal
 
I have the exact same motor and new lines tank carbs and diaphragms and it still is acting funky...only runs when pumping primer bulb so I am wanting to do the conversion. As well. Any help would be appreciated. Even a list would be nice and any problems existed...a lot of other sites say no don't do it
 
Can't be an electric pump! Mine cost me about 50 bucks and is marine approved. Gone are problems of air leaks at the connector, loss of vacuum for ?? reasons, etc. It's bullet proof.


One of the many nice features is running the motor dry on shutdown--a necessary action with today's gas. I just flip the FP switch to OFF as I run up on the trailer, then wait 'til she runs dry. Sweet!

Jeff
 
Cuz I'm telling you what when I get back there and pump primer bulb this thing runs awesome just kind of irritating that I have to do that and I'm worried about floating the carbs etc....that's my only worry. And just looking for someone that has done it as well
 
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