nissan marine wont start

[VAPORIZ3R]

I dont recall the year on the motor, but its probably 3-6 years old. My problem is that the motor was running poor so I decided to take apart the carberator and clean it. I didnt remove the jets. I pretty much took apart the easy stuff and sprayed it off with carb cleaner and put it back together and now it wont start at all :facepalm: Doesnt attempt to start now. I checked for spark which it has, compression shouldnt be an issue and the only thing left would be fuel. Fuel is getting to the carb, I just dont know what to check for now. Any ideas?

 

[pvanv]

Re: nissan marine wont start

Year is unimportant (except for warranty validation), but model/serial is everything for servicing. At least knowing the HP would help some. Nissan Marine has quite a number of carbureted motors (over 12) of that vintage (3 to 6 years old) in North America, ranging from 2 hp to 30 hp, and the servicing of them varies depending on the model/serial.

If it ran before you worked on it and doesn't now, you probably did something to cause the problem when you had the carb off. Time to get the carb properly cleaned and adjusted. You have an option: DIY or go to a dealer.

If you want to go through it yourself, get a copy of the Factory service manual (available from any dealer including me), and proceed with a proper carb cleaning: complete disassembly of all carb internals including jets and emulsion tubes, followed by a 4-hour soak in real carb dip, then a blow-out using carb spray to remove any dissolved varnishing, and then a careful reassembly and adjustment.

 

[VAPORIZ3R]

Re: nissan marine wont start

I looked and found the information you thought I should get. The model is NSF 18B2, the HP is 18HP 4 stroke. I know its my fault that it doesnt start now since it ran before I touched it and now it doesnt. When I dissasembled the carb I cleaned everything, but didnt blow out any of the holes with compressed air. It wasnt really dirty like I thought it would be. The only thing I think the problem may be is the or when reassembled do you need to pump the throttle alot to get the bowl in the carb refilled with fuel im just not sure about that or do I pump it with fuel a few times just to get it started. maybe it was the sensor connected to the top of the carb itself. I took that off and had a spring that needed to be centered when placing it back in, I believe. I dont think I got the spring placed back in properely nor do I know how important it is for just starting the motor. Do you know the name of that sensor and how critical is it to being placed in correctly? Seemed to be a bit of a challenge to get it in perfect :S I have a service manual that I found online for this and have been following the procedures but doesnt really cover the sensor at all. there is fuel getting to the carb because I pulled off the fuel line going directly to the carb and saw it spit fuel out, so it had pressure. Is there a battery for this? The manual said it had one but I didnt see one. If it does I could look for the correct voltage reading aswell. I didnt think it was necessary to take out the jets or any other parts seeing how it ran before and all it really needed was a cleaning and adjustment which im still planning on doing. Symptoms of what the motor was doing was running at very low idle, dieing constantly when trying to warmup even after warmup would eventually die if you didnt give it some gas. The gas is fresh btw. I also checked the fuel filter and had small bits of what to look like plastic to me, maybe was metal shavings. I cleaned that out until it was very clean to reuse. I cant get parts for it right now or I would but need some help on maybe what the reason is. Thank for your help

 

[pvanv]

Re: nissan marine wont start

OK, now we have something to go on. The 18B2 uses an automatic enrichment system, called "Auto By Starter", which performs the same function as an automatic choke would have back when we had carbureted cars. No, it does not require any separate battery; the motor will provide the voltage for the ABS solenoid when it's running. Yes, that could prevent a cold start if it has failed. It should be very easy to reinsert into the cavity on top of the carb -- if not, something may be wrong. No, no need to pump the throttle. although pumping the throttle will pump the accelerator pump, so if the carb is full, pumping would cause a stream of gas to spray into the carb throat.

You do need to squeeze the primer bulb in order to fill the carb, but that's the only pumping you should have to do. The fuel level in the carb is determined by the float pushing against the needle as the bowl fills.

I doubt that you found a Factory service manual online, as they are copyrighted, and so can't be published on the web. Now, if you bought a real Factory service manual from an online dealer, that's another thing entirely... The Factory manual will have complete servicing information for the fuel system, uncluding the procedure for testing the ABS solenoid. If you have an aftermarket manual, do yourself a favor and either give it to someone you don't like, or find some other non-repair use for it, such as a doorstop or woodstove tinder. The proper book covers 9.9hp, 15hp, 18hp "A" & "B" 4-stroke models, Part # 003-21041-0, $27.58, available from any dealer, including me.

If the fuel filter had visible bits of junk in it, I would replace it. While it's out, I would flush out the fuel lines to make sure there isn't any junk in them that would ultimately lodge in the filter. The part you need is 369022300M FUEL FILTER $11.07, available from any dealer, including me.

From your description, it sounds like you originally had some varnishing in the idle circuit of the carb, resulting in a poor idle. At this point, it seems you are getting fuel delivered to the carb, so start at the carb itself, aided by the real Factory service manual, and go through the carb completely. Yes, the jets and emulsion tubes need to come out during cleaning, or you have not gotten to the meat of the carb. It's possible that you have reinstalled the ABS module incorrectly as well, so check to make sure that the plunger is still intact, and is centered in the cup in the cavity of the carb casting.

If this job seems daunting to you, it's time to get to a dealer to have everything checked out, repaired and adjusted for you.