Please help. Engine won't start, suspected fuel problem.

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

I removed the solenoid spring from the choke flapper and operated the choke by hand. The choke plates return to the open position when I release them, as if by gravity. I've also operated the choke solenoid plunger by hand, and it seems to binding on the way out at one particular point. ie, when the plunger is pushed all the way in, it binds for the first 5mm on the way out, and then frees up and pops all the way out.<br /><br />I don't know if this info is of any use.

 

[SCO]

Re: Please help. Engine won't start, suspected fuel problem.

A carb rebuild is easy. You get a kit that has all the parts you need for little money, read up about it first in your manual. Helps to understand how a carb works so learn that too first. I agree w Rick that this is the next step with one caveat, that you fix the choke and test confirm that it still doesn't start. Sounds like maybe it could be the cause of the intermittent start. With choke on, the air is blocked, so that would be a good explaination for why it doesnt start with a stuck choke. Premix probably works with a good pull of air, but with little air I bet the premix doesnt get to crankcase in sufficient quantity. Ideally you just bump the choke to pull more fuel when you need it . Linkages etc. dont have to be reset.<br /><br />The solonoid is a simple electromagnet. When you flip the choke button, the electro magnet is on and pulls the plunger down against the spring. With choke off, the electromaget is off and the purely mechaicAL spring pulls the plunger up. Since it is stuck in the down/choke position, I am not suspiceous that the solonoid is defective. The plunger is binding or has too much friction. Could the solonoid be "on " all the time because of a stuck electrical switch? not if you can free the choke by hand and then the plunger is pulled down when you hit the choke button again. <br /><br />This should remain a single thread till we solve the problem and get the motor starting else we will have to look to 2 threads for background info. Cheers, lovely (note: thats the way they talk in England fellow iboaters )

 

[rickdb1boat]

Re: Please help. Engine won't start, suspected fuel problem.

If you have a digital camera, take pictures of the carb from many angles before you start. This will show you where the linkage goes if you forget. Barring the camera, make a drawing of the linkage for reference later on. The Manual should also have pics that will help out. Once you get the rebuild kits, it's just a matter of removing the linkage, fuel lines and any other hoses that run to the carb. Then remove the mounting bolts(Usually 2) and remove the carb. Work in a clean area, as there are some small parts that if dropped may be hard to locate. Get some carb cleaner(Spray) and if possible, a source for compressed air to blow out the passages. A computer store sells cans of compressed air that will work. Referring to your manual and any instructions that come with the kits, begin disassembly. It's really no big deal. More tedious than anything. Should be no surprises, if you follow the manual. Once disassembled, Spray all passages with carb cleaner and then compressed air. Reassemble using new parts and install on the motor again. The kit may come with"Extra" parts that you will not use, as the same kit may be used for other carbs, but nothing to worry about. You can always post back here if you get stuck. Stay with this post or you may lose us.

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

Thanks yet again for the invaluable advice. Will do as you suggest over the next few days.<br /><br />I certainly don't want to lose you guys now. Not after you have brought me so close to curing the problem.<br /><br />Spiffing ;o) Marvelous )

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

I took the choke solenoid off and cleaned the plunger up. It is working fine now, with chokes closing and opening easily.<br /><br />Today, I went to start the engine, but whilst squeezing the bulb to prime, I noticed petrol leaking from around the fuel filter cover on the fuel pump. I have just rebuilt the pump with a kit. I took the new filter cover gasket off, and put the old, softer one back in. This time when I primed, there was no petrol leak apparent.<br />Anyway, the engine started on choke and ran for a few minutes, although the revs kept increasing and dropping slightly as it ran. Then it died. This happened a few times.<br /><br />The engine would only run with the throttle flapper raised. Every time I lowered the flapper, the engine cut out. So I tried giving the engine some choke as it started to die, and the revs increased and the engine kept running for a short while until, again it died.<br /><br />It seems to me that it is drawing in air, probably around the filter, so I've ordered a new filter cover. Maybe the old one has become distorted. Also, I noticed that there is plenty of petrol entering both carbs, as some petrol was actually running back down the throat of the carbs and dripping into the air silencer back plate.<br /><br />What I now need to know is, should I still go ahead and re-biuld the carbs?, (the kits are on order), or is it likely that the filter cover is distorted and that the engine is drawing in too much air through the bad seal?<br /><br />Sorry for the long post.<br /><br />Thanks<br />Steve

 

[SCO]

Re: Please help. Engine won't start, suspected fuel problem.

I think you need to adjust the throttle closed position as per the manual first, as I think at idle you are forcing the engine to run rich according to my read of your description. I bet the air sucking is not the problem, but of course that should be setup as airtight as possible. Make sure the gas tank vent is open. Also, running the motor at idle on the flushette will cause the motor to idle poorly. You might want to run the boat at speed in the lake to clear out the engine from fuel/oil in the crankcase etc. I'm with you, dont do the carbs yet. Take care of these adjustments and get back to us. Once it starts w lever up and a bump of choke as needed to get it going, it will rev too high forcing you to move lever down on the properly adjusted engine. You should not be holding choke on except for bumps if it starts to die initially.

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

The last time the engine ran, prior to today, it idled without dying. I have not altered any of the throttle positions or linkages since then, or before come to that! All I have done is rebuild the fuel pump with a kit, removed the choke solenoid and cleaned it up and checked all the cables and wiring connections.<br /><br />It seemed today that the engine was running too lean without choke, or flooding with choke. There was no happy medium. Thats what it seemed like to me, but I am very inexperienced when it comes to outboards. I will, of course, gladly continue to act on your excellent advice <br /><br />I'll check the throttle closed position as you suggest, but I suspect it will already be set correctly, as I've checked the throttle and choke operation already over the last few weeks and they seemed to be fine.<br /><br />The carb kits and new fuel filter cover are on order, but won't be here until about a week after Christmas , so I'm limited as to what I can do in the meantime. Any suggestions?<br /><br />By the way, for future reference, what would the engine run like if it was actually pulling air in around the fuel filter cover?<br /><br />Thanks again<br />Steve

 

[SCO]

Re: Please help. Engine won't start, suspected fuel problem.

Steve,<br />If you dont have enough fuel to fill the bowls in the carb, it will die or maybe run lean since the bowl pressure is less, but the metering occurs in the carb. Next time it does that pump the bulb to fill bowls and see if there is a change. By all means though make it all air tight. Those fuel pumps operate on crankcase pressure, so check those connections and lines carefully. If it is too lean, then I suspect the carb jets or passages or vents are clogged or as you say maybe the fuel is just trickling into the carbs and not filling the bowls. The jets are sized to provide the correct mixture for the amount of air going into the carbs. <br />3 things are likely culprits. 1)fuel not getting to carb sufficiently, 2)misadjusted throttle(assuming we are past the stuck choke problem and choke is off), 3) clogged carb kets, passages , or vents. If #2 was the problem, you should be able to deduce this by manually operating the throttle...is the neutral lever opening the throttle enough to sustain idle? You should be able to test theory #1 by pumping the bulb. #3 is left if you are satisfied that it's not 1 or 2. I would put in a carb kit to satisfy myself that all was ok in any case because a clogged jet can cause a lean burn and overheat a cylinger.

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

Thanks again SCO.<br />I'll answer the questions you asked first.<br /><br />When the engine ran last time, I could "goose" the engine by raising and lowering the the flapper quickly. It sounded great and was right on the button. Today it was all I could do to keep the engine running. <br /><br />Today, with the throttle flapper raised, the engine ran at high revs, but as soon as I started to lower the flapper to bring down the revs, the engine died.<br /><br />I think I understand what you said about the throttle cable being spring loaded against the throttle stop. I'll check the throttle operation tomorrow.<br />With regard to your previous post, I run the engine in a large water butt on my drive. The engine is too noisy for the neighbours when it is run on the muffs <br /><br />What is really worrying me, is that I'm actually begining to enjoy working on this engine! I think I'll do as you suggest and fit the carb kits anyway, just for peace of mind. I'll let you know the result of the throttle linkage checks tomorrow.<br /><br />Thanks again for taking the time to give your advice. It is really appreciated.<br /><br />Steve

 

[SCO]

Re: Please help. Engine won't start, suspected fuel problem.

These are all things you should do anyway, but I hope it doesnt turn out to be an electrical problem. has to be fuel starvation. I hope and expect the carb kit and pump workover to solve this problem. Crossing my fingers here.

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

SCO<br />My fingers are crossed too!<br /><br />I checked the throttle sync today and adjusted as per the manual. I don't think that anything was out of place, but it has all been set again anyway.<br /><br />I did notice a few things which may not have been helping matters. Firstly, I checked the fuel pump connections again, and noticed that whoever had the pump off before I got the engine, had put gasket sealant between the gasket and the fuel intake hole on the engine block. Don't know if this prevented a good airtight seal, but I've cleaned it all off now anyway. Should I put sealant under the new gasket?<br /><br />Also, I noticed that the little plastic washer that secures the throttle linkage to the timing arm under the flywheel, was broken. The timing arm still moves with the throttle linkage, but there is some free play between the two. Maybe this accounts for the rough idle that I experienced before the engine developed starting problems? Anyway, a new washer kit is also on order now.<br /><br />I didn't try to start the engine today, as I didn't see the point. I'm going to re-build the barbs anyway, and have to fit the new fuel filter cover. It's just a pain that I won't be able to do these things for a few weeks yet <br /><br />Is there anything to gain from trying to run the engine again before this? Is there anything else I can be checking whilst waiting for my parts to arrive?<br /><br />Thanks agin<br />Steve

 

[rickdb1boat]

Re: Please help. Engine won't start, suspected fuel problem.

You do not want to run the engine with a lean condition. This can cause a cylinder to go south on you. as suggested, rebuid the carbs and I believe you will see a big difference. SCO is giving excelent advice!

 

[SCO]

Re: Please help. Engine won't start, suspected fuel problem.

That sealant sounds like a suspect...was it blocking the fuel path...you be the judge. There is no place for sealant in my view. What you need are properly sized fuel lines(OMC to be safe in selecting), clamps, gaskets orings. In the meantime, you I suggest that you evauate every fuel line from tank to engine and the lines to the pump. You are going to do a carb job, so Bristol fashion fitting of the lines leading to the carb are in order. I would also make sure tank is clean and that you have fresh fuel with TCW3 oil for the post carb startup . I replaced all fuel lines on my engine( a '73) with new stock OMC lines. I have heard of intermittent running problems being caused by deteriorated rubber chunks lodging/dislodging in fuel paths/carbs.

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

SCO & Rick<br />I really appreciate all the excellent advice. I'll renew all the fuel lines from tank to carbs as you suggest. Until the parts get here, I'll be studying my manual.<br /><br />By the way, is there a method of setting the floats without the special OMC gauge, or can I make one myself, given the dimension?<br /><br />What is the best method for cleaning my carbs? I've read on this forum that some people soak the carbs overnight in carb cleaner, but my manual says not so soak them, because of damaging the sealing compound around the metering chambers.<br /><br />Anyway, I hope you have a very merry Christmas and a happy new year.<br /><br />No doubt I'll be posting on here again in the new year to give you an update, or ask for more advice , so look out for me please

 

[SCO]

Re: Please help. Engine won't start, suspected fuel problem.

You can set the floats by eye, and the position should be shown in the manual. I use omc engine tuner to clean the carbs. It is soapy, and great to work with, and you can run the leftover through the engine to decarb as you should as a provisional. The only thing that might require a specialized tool is the jet removal screwdriver. You will probably be ok cleaning passages(with the pressurized engine tuner) to from the jets. Any suggestions about this anyone, agree/disagree about the jets removal?

 

[SCO]

Re: Please help. Engine won't start, suspected fuel problem.

Will be looking for a reply in this thread Steve. When we get the solution, this will be a good fuel trouble shoot thread, and maybe worthy for the repair faq section.

 

[rickdb1boat]

Re: Please help. Engine won't start, suspected fuel problem.

steviecops <br /><br />I wouldn't worry about removing the jets. I would do it the way I suggested in my previous post. No need to soak them if you are thorough in your cleaning. I did a pair of Carbs off a Merc that sat for 10 years and it worked fine, so I assume it will work for you. I did have a compressor that made it easier to blow out the passages, but the cans of compressed air will work fine.Float level is set by turning the Carb upside down and making sure the float is parallel with the carb body mating surface. Like this:<br /><br />

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

Thanks for the additional info. Don't worry, I'll certainly post the results of the carbs rebuid on here as soon as I get it done.<br /><br />I'm chomping at the bit now to get started. I've got all my tools at the ready, I've made a jet removal tool, just in case, and the work bench is cleared and ready.<br /><br />By the way, what is the most likely fault I will find when I strip the carbs down? Possibly the float needle or seat? Does the carb kit come with a new needle and seat? Is it common for the floats to be soaked to saturation as suggested in my manual?<br /><br />Thanks again<br />Steve

 

[rickdb1boat]

Re: Please help. Engine won't start, suspected fuel problem.

Float needle and rubber seal on it is the most likely culprit, along with clogged passages in the jets. Float needles sticking and unsticking at random in the jet, are not uncommon. The kit will come with everything you need, including new needles. Don't get freaked out by all the parts when you get them. Some may not be used in your particular situation. There will be new gaskets, new springs, ect.

 

[steviecops]

Re: Please help. Engine won't start, suspected fuel problem.

O.K, thanks Rick<br /><br />The parts should be here after the Christmas holidays. I'll keep you posted.<br /><br />Steve