cant keep yamaha running

[Danny1986]

first of all thanks to anyone that may be able to help me out. im not super knowledgeable with outboards so please bare with me.

i have a 1988 yamaha 30 hp precision blend outboard, model 30 ESG 2 stroke.

Here is the story. a few years ago i was low on money so i let it sit for a couple years. (ran perfect before this time). finally got a better job and started digging into it again and wasnt firing up. took apart the carbs and were filthy so i cleaned them out real good.

just started working on it again, took carbs out once again and recleaned every little part imaginable with the help of my father. jets and all. replaced fuel filter and fuel pump as well. before we fired it back up we put new gas in tank and new oil in reservoir. we also cleaned out all the lines leading to the carburetors.

we seem to be having problems with the gear linkage adjustment and carburetor adjustments the most. we could keep it running with the choke barely opened but once the choke was closed it died shortly after. what was odd was we put the lid on and i came back down the next morning (last week) and started it up and within a few seconds it stayed running without the choke at all. it idled high for a little bit then started sounding like it used to (nice low idle). so just today i came back down without making any adjustments and tried it again and it wont stay running unless its choked a little bit, second i close it it will idle high then bog down and die shortly after.

i found the specs for the enrichment screws which are top 5/8-1 1/8, middle 1 1/2-2, bottom 3/4-1 1/4. we had them set at 1 3/4, 2 1/4, 2 1/2. so i tried fiddling with the spec adjustments and cant keep it running without choke.

also, when i took apart the bolts that mount the carbs i lost all 6? small bolts i think they were around 3/4 long, but all the long ones are in and secure so maybe there could be a slight vacuum leak?

finally we are having problems keeping forward, neutral, and reverse all working. cant keep it in reverse at the moment. does anyone know where i can find the original specs for all of this so we can reset to where it is supposed to be. it seems like its 90% ready just got to figure all this timing stuff out. thanks

Dan

[TownsendsFJR1300]

Dan,

If you have a vacuum leak from missing, critical mounting bolts, that would cause the issue easily. Fix / install what you KNOW is broke/missing.

Here's the intake parts fisch to see what you SHOULD have:
http://www.boats.net/parts/search/Ya...AKE/parts.html


Here's the parts fisch for your carb: http://www.boats.net/parts/search/Ya...TOR/parts.html


If that does not fix the choke, idle issue, see below:

If it only runs with the choke on, the carbs are getting fuel BUT the carbs are not allowing fuel to flow (clogged).

Holding the choke, en riches the fuel mixture, thus it runs. Take off the choke, the carbs should flow fuel with air and keep running.

Pull the carbs again, pull the jets and make sure you can literally see thru them. If you don't have a shop manual, look up the carbs on the parts fisch on this page (up and to the right in RED-Purchase Yamaha Parts). Make sure your getting all the jets.

[Danny1986]

The jets were see thru cleaned all 3. Used carb cleaner and a small wire. Thinking the problem is the float settings. I took them off the first time and they may be out of adjustment. Found the correct spec for them so I will report back tomorrow with an update.

[TownsendsFJR1300]

Kinda odd all would be out of spec un-less someones been in there tinkering.

Re the potential vacuum leak, missing bolts, what happened with that?

[Danny1986]

Update

Took apart the carbs again. Cleaned everything and while taking floats out cleaned the valve needle if I'm reading the diagram right. One had some corrosion on it and didn't come out easy like others so cleaned it up sprayed carb cleaner through hole and re cleaned jets just incase. Floats were off my a couple mm so we adjusted them to spec. Top dead center was off a little bit so we aligned it up. Happy to say it runs great now. As for those bolts they were there to mount the cover to the carbs. Put them in a bag and no idea what happened to them.

[TownsendsFJR1300]

Glad to hear its running again and tks for the update.

You mentioned TDC was off a little bit. I'm not quite sure what you mean, the pointer, the cam belt off a tooth, ?


And you'll find your intake cover bolts right after you buy new ones!

[ausnoelm]

Cam belt??

[Danny1986]

The pointer was a little off.

Update. Tried taking it to the river and won't stay running. Never got it into gear. Kinda bogged down in neutral and had to keep giving it some gas to stay running. It would idle for a few seconds then die. Obviously it's needing more fuel due to more back pressure being fully submerged. I've read check for compression, change spark plugs, fiddle with idol speed etc. any other tips? Can't imagine the carbs are dirty since they've been cleaned twice now in 2 weeks.

[throrope]

Been there, done that, got the tee shirt and a one grand bill from the Yamaha certified marina.

I didn't address the upstream fuel system. With the next turn of the key all my own work was un-done.

The marina wouldn't back the job unless I spent three hundred to clean the tank and $3/gallon to dispose of thirty gallons of fuel. I replaced the tank, all hose, filters and fittings for half and filtered the old fuel into the truck with twice fresh gas.

Our lovely ethanol fuel reeks havoc on carbureted systems. The stuff gums just sitting. Most materials are rated for 10% ethanol, but the stuff will pull humidity out of the air and fall out of the gas to the bottom of the tank exposing materials to much more than 10%.

I rigged up $26 12V solenoid fuel pump to a 12 volt plug and spare fuel hose and pump all fuel into the truck, drain the bowls, empty the filter and leave tanks open and upside down to dry after every outing. No fuel to go bad. I went one more and replaced the fuel hose with 3/8" soft copper refrigerant line for 1/3 the cost of hose, except for a couple feet at the tank and motor that gets changed out every other year for ten bucks in ten minutes.

Had the boat out yesterday for the first time in months and ran like new. For me this success beats all the fuel stabilizer on the shelf.

Hope this helps, good luck and keep us posted.