70c carbs

Texastoon

Cadet
Joined
Oct 2, 2009
Messages
14
Just got carb kit today and getting ready to rebuild all three carbs. Motor has been bogging and not getting above 2500/3000 rpm. I got a small portable tank and ran good gas through and was still doing the same thing. In draining the fuel bowls I notice the bottom carb drain had some funky blue/green stuff on the end of the drain screw, so I order the kit.
My question is......... got any advice on the rebuild.
Do I need any special tools. I order the manual with the kit.
The manual said to use gasket sealer on the float bowl gasket. It's rubber, should I use the sealer.:confused:
Think I can manage the rebuild, but the syncro afterwards looks a little tricky.
Any advice from the pros/guru would be taken to heart.:cool:
Thanks
 

Texastoon

Cadet
Joined
Oct 2, 2009
Messages
14
Re: 70c carbs

Forgot to ask how to remove the choke. The thin wire from the solenoid looks real easy to mess up.
 

intrepidvoyager

Petty Officer 1st Class
Joined
Mar 24, 2009
Messages
216
Re: 70c carbs

Could be the carbs but if you are getting to 3000 RPM could also be fuel delivery as in fuel pressure from the fuel pump ...you can get a test guage for around $30 ...... if it's still a carb issue apart from soaking as suggested in most manuals get a spray can of carb cleaner with the little red tub and spray cleaner in all the holes .....here is a little write up i did for a guy with an idle problem, but the same applies to the high speed jet(s) in your carb could be called the emulsion tubes ...... cant help you with the choke as don't know your set up, but all the carb stuff is generic.... re the gasket ..if its an o ring profile you dont need sealer. good luck.

HERE IS HOW TO CLEAN ... there are as you may know 2 parts to this ...fuel delivery and air delivery ..got to be close to 14 to one or won't work .. the idle fuel port is a tiny hole in the venturi ... it is fed by a tube going into the float bowl ...so skuirt LOTS OF carb cleaner in the idle fuel tube and make sure it comes out in the venturi. there may be two or 3 tubes ..just find the right one .... you got to make sure idle fuel is getting to the venturi ......NOW screw out the idle mixture screw half way and repeat the process ......carb cleaner should come out both the fuel port and the AIR supply somewhere ....if not put your finger on the venturi fuel port and skuirt more carb cleaner into fuel tube ... if no carb cleaner comes out somewhere the idle air delivery is blocked ....once its clear put your finger on the fuel port and spray LOTS OF cleaner both ways . its not only dirt you are looking for .... old fuel glaze ..really bad if you use gas with ethenol in it. some carbs have a removable mixer jet .... if you can't get it out just repeat the cleaning process ten times. By now you should be soaked in carb cleaner ...if not you have not used enough .. .... now if your idle screws have o rings replace them ...sometimes i find they are missing ..... coat the o ring with vasoline when you instal so the o ring does not get hung up on the hole ...
 

TOHATSU GURU

Admiral
Joined
Jul 22, 2004
Messages
6,164
Re: 70c carbs

No special tools needed. Clean carbs by dipping, sealant not needed....Sometimes it helps hold a difficult bowl o[ring in place while mating the surfaces. It takes an ear to synchronize carburetors correctly as each one is minutely different. Just do the initial setting and then take it to a marine mechanic for the final adjustment....Or you can set them a 1/4 turn rich to start off with and if you foul out a plug in an hour lean out that carb an 1/8 of a turn. Repeat until you get 20 hours to a plug. That's a BS 3rd world method, but it actually does work if outside service is not an option.
 

Texastoon

Cadet
Joined
Oct 2, 2009
Messages
14
Re: 70c carbs

I rebuilt the carbs over the weekend in between some other chores, soak time seemed to be just right for me to get sick of doing something else.
Here's thanks to INTREPIDVOYAGER AND TOHATSU GURU.:D:cool:
The motor sounds great and I just need to get it to the lake and test it under a load. The carbs were progressively worse from the top down.
Maybe this fixed the problem, if not I'll be back right here on this tread.
Thanks again.
 

intrepidvoyager

Petty Officer 1st Class
Joined
Mar 24, 2009
Messages
216
Re: 70c carbs

Good Stuff ..... would also appreciate a post if it did do the trick as always like to know the outcome either way. Cheers !:)
 
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