Carb Cleaning - I am in too deep to turn back

[BIGKAHUNA]

Well I tried a few things to get my '87 Yamaha 70hp going but no luck. I decided to dig in and removed the carbs and seperated them. So far so good. I marked each carb as to its position in the order and am now ready to disassemble.

Here is my dilemma - get a gallon of carb dip and clean or rebuild? I am about out of expendable cash and thought I might be able to save the $150 my local Yamaha dealer is asking for kits for all 3 carbs ($50 ea. Carb). A poster )has same motor as me) on a fishing forum I visit said he ran across the same problem - he bought a gallon of dip and cleaned all 3 carbs and says his motor now runs better than it ever has.

I would like opinions as I am a novice - is there any reason not to try the cleaning method first? Can I get by without the kits?

[keithsturkie82@gmail.com]

I have cleaned my carbs 6 times without the kits. Be sure to not get any cleaner on the gaskets because this will over time destroy them. Be sure to check and make sure the gaskets are in good condition prior to re installing them also. Clean carbs really really good and let them soak over night. Take them out and dry them and if possible use compressed air to blow residual cleaner out. Then re install gaskets and put them back on your motor and u should be good as new.

[Haynick1]

Keith is correct, I have cleaned the 3 carbs on my 90 hp 2 times and only had to replace (1) $2 O-ring, be sure to leave the throttle linkage attached to the bottom carb or mark it, mine will go on either way, if it doesnt go on the same way the carbs will not be in synch. also, dont make any adjustments to the carbs, and be sure to remove both jets, when I finished my boat ran 6 mph faster and performed much better

[BIGKAHUNA]

Keith is correct, I have cleaned the 3 carbs on my 90 hp 2 times and only had to replace (1) $2 O-ring, be sure to leave the throttle linkage attached to the bottom carb or mark it, mine will go on either way, if it doesnt go on the same way the carbs will not be in synch. also, dont make any adjustments to the carbs, and be sure to remove both jets, when I finished my boat ran 6 mph faster and performed much better

I marked all 3 carbs as too position. The only adjustment I made was I removed the mixing screw. I seated each first and counted the number of turns to a lightly seated position. I have one mroe carb to tear down nad dip.....hoping this works. The second or middle carb had huge chuncks of solidified debri in it.

[BIGKAHUNA]

Is 2 hours long enough to leave the carbs in the dip?

[TownsendsFJR1300]

Carb

If you remove the float bowls, there should be two jets inside, a larger MAIN jet and a smaller idle jet.

These jets, especially the idle jet tend to clog up with varnish if the engine sits alot with no fuel additive and especially if you use ethonol fuel.

IMHO, I'd remove the carbs, float bowls and clean the jets by hand. I wouldn't rebuild them unless you see obvious worn parts (needle and seat). You can use regualrt carb cleaner on the bowl if varnished up. I'd keep the carb cleaner away from any o-rings as some products are quite aggressive..

And start using a fuel additve, Seafoam works very well at cleaning and storage of fuel. Chevron techtron is a very good cleaner.

If your really lazy, drain the carbs (drain screw on the bottom of the float bowl) and fill with straight Seafoam (thru the fuel inlet hose). Let sit for a day and drain. I've seen Seafoam clean a totally clogged MC carb this way. And it won't hurt any o-rings/gaskets...

If strictly using dip, I'd keep them dipped as long as the instructions direct you too...

[BIGKAHUNA]

If you remove the float bowls, there should be two jets inside, a larger MAIN jet and a smaller idle jet.

These jets, especially the idle jet tend to clog up with varnish if the engine sits alot with no fuel additive and especially if you use ethonol fuel.

IMHO, I'd remove the carbs, float bowls and clean the jets by hand. I wouldn't rebuild them unless you see obvious worn parts (needle and seat). You can use regualrt carb cleaner on the bowl if varnished up. I'd keep the carb cleaner away from any o-rings as some products are quite aggressive..

And start using a fuel additve, Seafoam works very well at cleaning and storage of fuel. Chevron techtron is a very good cleaner.

If your really lazy, drain the carbs (drain screw on the bottom of the float bowl) and fill with straight Seafoam (thru the fuel inlet hose). Let sit for a day and drain. I've seen Seafoam clean a totally clogged MC carb this way. And it won't hurt any o-rings/gaskets...

If strictly using dip, I'd keep them dipped as long as the instructions direct you too...

The instructions say 15-30 minutes and no longer than 4 hours. I think I am good.

[TownsendsFJR1300]

Carb

Sounds like it. Please post how it turns out..

[BIGKAHUNA]

Sounds like it. Please post how it turns out..

Well it turned out great! I reassembled the set and installed, turned the key and almost instantly my motor fired up and was running great. Idled great and I rev'd it a little and it seems fine. Now I'll have to see if it holds up underload.

On a side note - Yamaha did a great job engineering the fuel system on this motor. It was actually a very, very simple task that required NO special tools. All connections were easy to access as well. I cant for the life of me fathom how my local service centers charge $350-400 for this service. Degree of difficutly is extremely low and not much actual work time involved. Waiting for the parts to soak is the only thing that really takes time.

[99yam40]

Time is money at the shop.
Shop time starts when they hook up to boat to pull into shop to troubleshoot and includes putting in tank and testing the motor after repairs are made.
And their hourly rate is high to cover the overhead of paying for everything they need to keep the doors open all year around and giving Uncle Sam his cut

Some people are not good with their hands and are afraid of getting into things they have never done before. But if you pick up a service manual and are able to read and understand what you read, then most simple repairs are no problem

[TownsendsFJR1300]

Well it turned out great! I reassembled the set and installed, turned the key and almost instantly my motor fired up and was running great. Idled great and I rev'd it a little and it seems fine. Now I'll have to see if it holds up underload.

On a side note - Yamaha did a great job engineering the fuel system on this motor. It was actually a very, very simple task that required NO special tools. All connections were easy to access as well. I cant for the life of me fathom how my local service centers charge $350-400 for this service. Degree of difficutly is extremely low and not much actual work time involved. Waiting for the parts to soak is the only thing that really takes time.

Excellent!

As noted above, IMHO, start using Seafoam for stabilizing fuel, Yamalube RINGFREE for cleaning the fuel system and engine and you won't have to repeat the job again... If the soaking missed anything, the Seafoam or Yamalube will clean up what's left. Fuel goes foul in as quickly as a month. Fuel sitting in a carb for longer than that will result in MORE CLEANINGS..

+1 on tackling at least some of the simplist jobs. With a manual, it'll help you understand how the engine works. The more you know, the more you can do yourself, also comes in handy when out in the middle of no-where!

[99yam40]

Excellent!

As noted above, IMHO, start using Seafoam for stabilizing fuel, Yamalube for cleaning the fuel system and engine and you won't have to repeat the job again... If the soaking missed anything, the Seafoam or Yamalube will clean up what's left. Fuel goes foul in as quickly as a month. Fuel sitting in a carb for longer than that will result in MORE CLEANINGS..

+1 on tackling at least some of the simplist jobs. With a manual, it'll help you understand how the engine works. The more you know, the more you can do yourself, also comes in handy when out in the middle of no-where!

Not sure why you say Yamalube cleans motor and fuel system as it is oil.

Maybe you meant Ringfree

[TownsendsFJR1300]

Not sure why you say Yamalube cleans motor and fuel system as it is oil.

Maybe you meant Ringfree

Yes, Yamalube Ringfree is what I meant to say, my mistake.

[BIGKAHUNA]

Time is money at the shop.
Shop time starts when they hook up to boat to pull into shop to troubleshoot and includes putting in tank and testing the motor after repairs are made.
And their hourly rate is high to cover the overhead of paying for everything they need to keep the doors open all year around and giving Uncle Sam his cut

Some people are not good with their hands and are afraid of getting into things they have never done before. But if you pick up a service manual and are able to read and understand what you read, then most simple repairs are no problem

Time is definitely money and overhead can be overbearing. That being said this carb cleaning should cost $250 MAX. That is a fare price. $400 is getting a little deep.

[99yam40]

I agree, that is why I do most all of the maintenance on all of my vehicles and toys.
It gives me a good feeling to have accomplished something at the end of the day
By the time they pay the mechanic, the parts and shipping, the parts person, secretary
( phone answerer),all the shop bills( insurance, elect., gas, water ,sewer, garbage, etc) it does not leave a lot for the owner and uncle SAM.

The manuals are not cheap for us to buy, but think about buying manuals for all of the motors they have to work on.