Fuel Starvation and Other ?'s

[billybandman]

I am new to the board. Great Board. Read the whole forum last Sunday night. I have a number of questions regarding a '64 Merc 50 that was given to me for an old Dory that I have. I Have come to the conclusion that fuel starvation is a problem as it will not run with a load on it, in gear,at higher rpm's than idle, I can gingerly work it up to about 3,500 rpms, in gear,tied to the dock, by fiddling with carb linkage, and distributor, It is a motor that a guy gave to me and runs great with the muffs on it, in gear. <br /><br />I was told by our local Merc dealer, very nasty guy, that he won't work on anything that old so I'll attack this thing. I am a diesel mechanic. I was also told that I couldn't buy a fuel pump rebuild kit for a motor this old. Is that true. or where can I get the kit? <br /><br />Can I gerry rig an electric pump to see if the pump is the problem. If so, how much pressure or should I just throw on a small universal electric and see how she runs. next...<br /><br />I will change the hoses, tank, bulb, and check for fuel line leaks, next..<br /><br />I have no idea if this motor has been sitting for a while but is there a product that may help devarnish the carbs without removal and rebuild I will decarbonize the motor too.<br /><br />Sorry about the long post.

 

[Liam]

Re: Fuel Starvation and Other ?'s

I had a similar problem. Motor would run great without load or when cold. When I got it running for a short time it acted as if it was fuel starved and would bog down. It ended up being a power pack that broke down when it heated up.

 

[dkondelik]

Re: Fuel Starvation and Other ?'s

Hi "C",<br /><br />couple of thoughts.<br />once you get the problem defined, there are probably replacement parts avaiable at miriad locations.<br />once you've got the source of the problem figured, let us know what your looking for. There will likely be multiple suggestions for where to find it.<br /><br />in the mean time, it might be suggested that you get a manual for your motor, you can probably find one at the link at the bottom of the page. if you can't find one, let us know. there are several sources for aftermarket and oem-reprint manuals.<br /><br />it might also be suggested that you run a compression check. this may let you know if the motor has a chance of running. the compression ought to be in the 100+ range and readings should be within ~10% of each other. <br /><br />if you get a low reading(s), might just be carbon build-up on the rings. or you might just go ahead and pull off the exhaust cover so that you can give a partial inspection of the condition of the cylinders/pistons. sorry, not familiar with you engine BUT if this ol' Merc has a removable head AND if your compression is low, just pull of the head for a better view of piston tops and cylinder walls.<br /><br />also suggest, With your manual, remove, clean and rebuild the carb(s). can probably find carb kits at:<br /><br /> http://www.maxrules.com/ <br /><br />as well, if you don't know the last time that the water pump was serviced, go ahead and attend to that.<br /><br />this reply is getting a bit long. how about refering to this link.<br /><br /> http://www.precisionserv.com/Outboards/Revitalization.htm <br /><br />i hope this can help get you started.<br /><br />let us know what you find.<br /><br />Good Luck!<br />HAVE FUN!

 

[Wide_One]

Re: Fuel Starvation and Other ?'s

I am definitley not a boat mechanic but I would say it is the fuel pump. I am having the same problem but I can get a kit for mine. If you search the site you will find information on electric fuel pumps. I can also tell you that the people who know will tell you to get a carb kit and a manual and take the carbs off.

 

[horndog]

Re: Fuel Starvation and Other ?'s

maybe its an accelerator pump in the carb?

 

[tmcalavy]

Re: Fuel Starvation and Other ?'s

Man, a 64 Merc 50 hp. Wish my 74 Merc 500 was that vintage. Simplicity and reliability all rolled into one. Test the fuel pump by squeezing the fuel/tank bulb as it bogs down. If it responds you've got a fuel pump problem...most likely a bad diaphram. Get the Seloc manual for this engine...they show up regularly on ebay for less than $20. If you're a diesel mech you can learn how to do everything to that Merc, except a complete rebuild, from the Seloc manual. Including diagnosing and fixing the bogging problem. Meantime, check out www.oldmercs.com and Johns Old Merc page at www.pfs-ware.com. Keep us posted, preferably with some pix.