Starting problems with 25 merc early nineties

[kalpakis]

Hi<br />Can anyone tell me about this problem? I changed the carburator on my 20 hp Merc early nineties for a 25 carb.I got it started with alot of pulling. Once it was going it was smooth and ran very well. I stopped for an hour and it started with a lot less pulling but about 5 to 7 pulls and a couple sqeezes on the fuel ball. My previous carb 20 hp would start with 1 or 2 pulls warm or cold it started quickly.<br />Kalpakis<br />Thanks

 

[andy6374]

Re: Starting problems with 25 merc early nineties

What is your startup procedure?

 

[kalpakis]

Re: Starting problems with 25 merc early nineties

Hi <br />I prime the bulb till it's firm, then pull the chock and then pull on the cord till it turns over. After it dies I then push the chock back in and start pulling the cord. It turns over for 15-20 seconds then dies. I really don't know what the best order is.<br />Thank you<br />Kalpakis

 

[DHPMARINE]

Re: Starting problems with 25 merc early nineties

I don't know how the larger carb will act on your motor but it seems to be giving you hard starting.<br />I would totally rebuild the NEW carb and see what happens.If you still have problems,go back to the old carb.I don't think you are seeing any benefit with your upgrade.Except agrevation.<br /><br />DHP

 

[kalpakis]

Re: Starting problems with 25 merc early nineties

Hi<br />When u say rebuild the new carb do u mean change all the gaskets,diaphram and needle,etc.<br />When I had it out it ran very well and alot more power.<br />Starting is tough though.<br />Thanks K

 

[DHPMARINE]

Re: Starting problems with 25 merc early nineties

I would dissassemble,clean and reassemble with new gaskets and diaphrams.The "choke" part of your carb includes a diaphram "plunger" pump assembly on the port side.If it has dirt in it,or a bad diaphram,it won't supply enough fuel for good starting,when cold.<br /><br />DHP

 

[Laddies]

Re: Starting problems with 25 merc early nineties

There is a ball check on the primer that gets stuck and causes problems with the float bowl off the carb fill the bowl and push the primer and it should squirt fuel out a small hole in the top face of the bowl

 

[kalpakis]

Re: Starting problems with 25 merc early nineties

Hi<br />Thank's for the advice, I will clean the Carb but what products do u suggest to clean it with. What does a bad diaprham look like? Also what should I put on the new gaskets?<br />Thanks <br />Kalpakis

 

[Laddies]

Re: Starting problems with 25 merc early nineties

Clean it with a spray carb cleaner, do not soak it in automotive claener it will damage the castings, usally a bad dia. will leak when priming. The carb kit for that unit is quite expencive, so I you are carefull and don't damage the gaskets you should be able to reuse them

 

[andy6374]

Re: Starting problems with 25 merc early nineties

Laddies-<br />I wasn't aware the automotive stuff, say like MAC's that you can get a NAPA, is not recommended for use on marine carbs. Is there any marine carb cleaner you can buy by the gallon? I like the gallon stuff because you can fully submerge the carbs into the liquid and thereby guarrentee every part/orfice has been thoroughly degreased.<br /><br />Thanks

 

[Laddies]

Re: Starting problems with 25 merc early nineties

If we soak one it's in lacquer thinner or acetone

 

[kalpakis]

Re: Starting problems with 25 merc early nineties

Hi<br />I was wondering about the brass needle above the throat on my carb. What is the right amount of turns out that it should it be at?<br />Kalpakis