1973 eVINrUDE 25hp sputters and pops

[fishfighter]

1the motor runs great wot for the most part but when I go to neutral it almost always sputters and pops more or less like a backfire, sometimes the motor will stall if left in neutral but I try not to run it in neutral if I can help it. I have replaced the following in the last 4 months-fuel pump, fueltank and line, plugs among others. 2I also have a separate issue I assume and that is today when I drained the lower unit fluid it is white. is the fluid a clearish black when it was put in? I dont know how long it has been since the last change. I have had the boat for 5months and used it everyweek atleast once with no prob except above. any suggestions appre

[stan_deezy]

Spluttering and popping in idle: have you cleaned the carb?If not try that: and do a search on here for how to set the idle needle: easy when you know how.Check back and let us know how you got on with the carb clean and we'll take it from there.Lower oil white: means water has got in. If you can take it to a shop and get it pressure tested.If you can't take it to a shop then refill with fresh oil and run it for a while and see if you can spot any leaks.

[fishfighter]

I have not had the carb cleaned is that hard? I got a manual, maybe someone knows of a site w/better pics as the manual lacks. the needle I have not screwed is in to near tightand backed off 1.5 turns as it says but I have it adjusted to what seems to be the best spot. the sputtering and stuff only really happens in neutral. I drained it last night )seems to be no metal particals( and today filled it and ran it for 20-30 min in my test tank (50gal plasticdrum and left it in the water, I guess tommorow I will drain and inspect. to clean the carb will I need to dissasemble it? if so do I need to replace anything inside or buy anything? thanks for the help.

[fireman57]

It's not too hard to rebuild these carbs. Just take your time and make sure that all passages are clear. You may need to take a very small wire and clear anything stuck in the jets/seats. Make sure you blow everything out well with compressed air.The kits are pretty cheap and after that it is nothing but time. It may take you longer to remove the carb then clean it and rebuild it.

[stan_deezy]

yep, I'd definitely go with a carb strip and clean out first. Like fireman57 says: it's time rather than money on that carb, and it is fairly simple. I know the screw you're talking about and that is the idle mix screw so it won't affect the performance at anything other than idle. Possibly just tweaking that "might" help but remember to take it slow and wait for 15-30 seconds to see the difference: she won't respond much before that time elapses.Let us know what you find when you look at the lower unit oil.

[fishfighter]

bare with me I have been working out of town for another week and I will have time for a look at the lower unit oil color and the carb.

[G DANE]

In many cases a little water in lower unit oil comes from old leaking gaskets on fill and vent screws. Thats simple to change, you can even do it with the oil in it, one screw at a time and top up afterwards. Run it in water under load, and check after a couple of runs. If you will need to, your exact type of lower unit is the easiest to work on, and takes only standard tools. Do a search here for Iddle mixture adjustment, and you will find an excellent discription to do it with the boat in water, by Joe Reeves. But if your carb hasnt been cleaned and rebuild for years, do it, you might pick up some high speed performance and easier starting too.

[fishfighter]

got her running today (after carb rebuild) she idles alot better, havent checked the lowerunit oil yet but I did put the new seals on the LU plugs and new oil. the motor still kinda jerky and it smokes like hell from my test tank. It leaves a bunch of grease or oil or something floating in the tank, is that normal for an old motor?

[tashasdaddy]

running in a tank, the film is normal. set your "low speed idle" screw, but using Joe Reeves post. use the search function. it has all you need to know.

[Lubosleftboot]

Originally posted by fireman57: It's not too hard to rebuild these carbs. Just take your time and make sure that all passages are clear. You may need to take a very small wire and clear anything stuck in the jets/seats. Make sure you blow everything out well with compressed air.The kits are pretty cheap and after that it is nothing but time. It may take you longer to remove the carb then clean it and rebuild it.

Clean with carb cleaner and compressed air do not put wire into any of the jets or passage ways as this can damage them

[fireman57]

A good overnight soak in cleaner usually will remove enough stuff that compressed air will clean them. When I suggested a very small wire I mean one that foes not fit tightly in the jets but just has enough strength to loosen anything that may be blocking it. Don't give them a reaming.