Fuel problem, please help. - Page 2

Blue_Runner · #1 08-03-2010, 07:57 AM

LMAO!!

Pictures ARE cool aren't they? No pics. He rebuilt the two pumps and showed me the one diaphragm that had a HOLE in it. He said it looked like our good buddy ethonal caused it.

Yesterday evening as I was about to put some burgers on the grill I got a phone call to meet him at the ramp for a test drive.

**WARNING - WHAT YOU ARE ABOUT TO READ IS SHOCKING**
I reluctantly turned the burger grilling operation over to my wife.
** TOLD YOU IT WOULD BE SHOCKING**

From there I headed to the ramp and we dropped it in the water for a test spin. I drove it like I stole it and no hesitation, no starving for fuel, none of that. She purred above 4500. Problem solved!!!

While in the shop I had him replace the impeller, which I had already purchases for $25 (was going to do it myself) and supplied to him. He did that and replaced the o rings around the housing as well. Total out of pocket is $200 for the whole job - 2 rebuilt fuel pumps and replaced the impeller and o-rings. I was like, "is that it, $200?" I think I found my new favorite local outboard mechanic!!

p.s. wifie did a spectacular job on the burgers and I scarfed down 2 of em when I got back. Props to Mrs. Blue!

jjjtronics · #2 06-29-2010, 08:58 AM

Try this; using a piece of clear fuel line, adapted inline with the fuel line, look for air bubbles running along with the fuel flowing while the engine is at the failing rpm. If you see air bubbles, you have got a vacuum leak somewhere, and that will make your life misserable.
I had a VERY similar problem once, using this clear line method, found a microscopic pin hole in the aluminum fuel pick up tube in the tank.
Remember that thanks to whoever made it a design-rule-law, outboards run on a vacuum- type fuel system all the way up to the pump, which is mounted next to the carbs/injectors, that way there is never-ever pressure on the fuel lines from the tank, which avoids leaks and fire hazards to almost zero. But vacuum leaks are hard to trouble-shoot, but, if the pums are pumping well ( checks with fuel pressure gauge ), and the fuel supply is good ( enough and free of bubbles ) your motor should run good, unless there is a problem with the motor itself.
If you have good fuel supply, I have cleaned my Yamaha`s carbs a couple of times and could help you out on that.

Blue_Runner · #3 06-29-2010, 09:08 AM

Thank you JJJ, good ideas.

I've cleaned my carbs with some help from a buddy twice. Might be time to try that agian. I will go ahead and get a carb kit to replace the gaskets. Last time in they were a tad brittle which makes me suspicious.

nymack66 · #4 06-29-2010, 09:35 AM

BTW where are the pictures ? :)

Blue_Runner · #5 06-29-2010, 09:47 AM

My goodness, I'm in crisis mode...my boat is in ICU and all you can think of is pictures! Shame on you!

Blue_Runner · #6 08-02-2010, 02:25 PM

Update: I took the boat to a guy down the road who has quite a bit of experience working on outboards. He diagnosed it as have a bad fuel pump (1 of 2). Well this is great news because it is exactly what I suspected.

He is replacing both fuel pumps and I am supposed to be able to pick it up this evening. If I get it in time I'll be off to the lake for a test run. Wish me luck!! I'm ready to get back out there. I haven't put nearly enough hours on it this year.

#7 08-07-2010, 12:57 PM

Try this troubleshooting procedure. Disconnect the fuel supply hose at the engine. Connect it to a clear plastic hose then connect the other end of the clear hose to the engine. Start the engine and look for signs of air bubbles indicating that you are sucking air somewhere vice solid gas. I used this procedure before to find the same problem. My problem was the clamp holding the vaccum hose to the pulse limiter on the crankcase had come loose. I did not have enough vaccum at high speed to suck enough gas to the fuel pump(in my case not enougn vaccum to the VRO) when trying to get on plane. If you see air bubbles then troubleshoot from there. Also try an external tuel test tank also with a clear hose to eliminate your built in fuel tank and hoses an a source of the problem.

wwatterson
1987 Wellcraft V20 Fisherman with original Sea Drive

spareparts · #8 08-07-2010, 08:53 PM

used to be, you hardly every went into the VST, now it seems like an anual occurance. I've all kinds of rumors about whats causing teh trash and why it gets past teh filters, best thing to do is runa good water separating filter, and change it often. I've seen some shops install a suzuki high pressure filter between the vst and the injector rail, it seems to help

THEFERMANATOR · #9 08-07-2010, 09:01 PM

Quote:

Originally Posted by wwatterson

Try this troubleshooting procedure. Disconnect the fuel supply hose at the engine. Connect it to a clear plastic hose then connect the other end of the clear hose to the engine. Start the engine and look for signs of air bubbles indicating that you are sucking air somewhere vice solid gas. I used this procedure before to find the same problem. My problem was the clamp holding the vaccum hose to the pulse limiter on the crankcase had come loose. I did not have enough vaccum at high speed to suck enough gas to the fuel pump(in my case not enougn vaccum to the VRO) when trying to get on plane. If you see air bubbles then troubleshoot from there. Also try an external tuel test tank also with a clear hose to eliminate your built in fuel tank and hoses an a source of the problem.

wwatterson
1987 Wellcraft V20 Fisherman with original Sea Drive

Using clear hose to look for air bubbles isn't the best test anymore. With E-10 fuel it can generate air bubbles in the fuel on a hot day now.