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Very hard to start when cold (DT75)

Also, how long would you recommend I leave the carbs in the ultrasonic cleaner?


I should probably change the title of this thread - turns out it isn't very hard to start - just impossible to keep running. :)
 
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i use

vinegar
hot water
and dawn soap

then rinse in fresh water

do ot soak them

sorry for delay was away from puter for a week!!!

a little warm mexico sun!!!
 
Hope you had a good vacation!

I'm going to be borrowing the ultrasonic cleaner next week or next weekend. Its not very big so it will probably only fit one carb at a time, but it will still work.

I'll post what happens!
 
Not all ultrasonics are the same.-----------I remember working with one where you where afraid to stick your hand in it.-----------------And one that you had to look twice to see if it was in fact " on ", so judge the time required accordingly.
 
Not sure how this one works, I only flipped it on for a second and heard it working. (Had no fluid in the stainless steel tub though).

I'll leave em in there for 30 min to an hour; I'll let the commercial breaks decide when I take it out lol

One more thing - I just noticed a disconnect between the Clymers manual and the green Suzuki Outboard Motor Service Manual. The Clymers manual calls for a float height of 0.39-0.47 in, where the Suzuki Outboard Motor Service Manual calls for a float height of 0.69-0.77. That is quite a difference - I went with the Clymer's manual because that is what I had with me at the time.

Does anyone have any thoughts on what the float height should be for these carbs?
 
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There is something wrong with one of the manuals.-------That is typical of aftermarket manuals. -----------Read them carefully as one may be " metric "----------In general floats will be level / parallel when turned upside down.
 
FACTORY ONLY

they built it, they should know

funny sheet, i was thinking about carbs specs today watching the 49ers get their butt waxed!!!
 
Here's the weird part:

When the floats are set to the Clymer's manual (0.39-0.47) the floats are level when turned upside down. I set them to 0.43 for a relatively nominal setting.

I am pretty sure if I set the floats to the factory manual setting, they will be leaning downwards when the carbs are upside down. But, it was supplied by the factory, so I will try it after I clean out the carbs.
 
Took the first carb out and ran it through the cleaner. It seems like a weak cleaner so I left it in there for an hour and a half. Rinsed it well with water, the passages seem clear.

For reference, when I tried to set the float height per the Suzuki manual, I found that it was impossible. The float actually hits the body of the carb before you can reach the 0.69" height recommended by the service manual. I was measuring it as shown in the diagram, but there has to be a mistake somewhere.
 
Ok. I forgot to bring them with me; I was going to scan them at work and post them.

They both depict measuring the float height in the same (or at least a very similar) manner. Basically measuring using a caliper from the top of the main jet down to the float with the carburetor upside down. Using this method, you can't use the Suzuki manual recommended height since the float hits the carb body before you reach it. The Suzuki manual shows both metric and English units of measure, so there is no confusion there. (17.5mm or 0.69" minimum - its the same)

I'll try and snap pics of each manual and post those this evening.
 
Here is a pic of the manuals in question:

OutboardManuals.jpg


This is how the green Suzuki manual shows to measure the float height:
SuzukiManualFloatHeightDiagram.jpg


The same green book lists this table for the carb specs, note that the float height is in fact 0.69"-0.77". The fact that the metric measurements correspond correctly to the English measurements lead me to believe that the measurement is intentional.
SuzukiManualCarbSpecTable.jpg


The Clymers manual shows a similar diagram for measuring float height, albiet in a slightly different spot. However taking the measurement at either spot won't alleviate the float hitting the body before you can reach the 0.69" measurement.
ClymersManualFloatHeightDiagram.jpg


I tried to take a pic of the table in the Clymers manual that lists the float height, but it didn't want to come out. It is listing 0.39-0.47" for 87 and up DT75.

Here is specifically the problem I am running into with the float height. I couldn't get it all in one pic, sorry. The first pic is showing the float as far down as it will go (hitting the body of the carburetor):
FloatHeight1.jpg


And the 2nd is the measurement when it is as far down as it will go:
FloatHeight2.jpg


So I can't ever reach the 0.69" min called out by the Suzuki manual, no matter where around the float I take the measurement. When the float is set to the Clymers manual setting (0.39-0.47") the float is sitting basically level when the carb is upside down - which in my limited past experience is correct.
 
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Will do.

Still gotta run the other two carbs through the cleaner - I have tomorrow off so I plan to do it then. I may run the first one through it again to be on the safe side, and re-blow the passages out with an air compressor. There were some small particles floating in the cleaning fluid after the first carb was finished, but I have no idea where they came from.

I'll post what happens.
 
Ok, ran them all through the cleaner. I managed to get the main jet and nozzle out of the bottom carb - most of the holes in the nozzle were plugged up with crud, and crud came out of some of the passages when I blew them out with compressed air. So that was definitely a problem with the bottom carb.

The middle carb is still a problem. I noticed that not even compressed air is freeing up the passage between the main nozzle and one of the holes at the top of the carb. (On the other two, water and air were able to flow freely though this hole.) I can't for the life of me get the main nozzle and jet to come loose - it looks like someone has tried it before due to damage to the hex, and I added to that damage. They need to come out because I believe they are plugged and crudded up like the bottom carb was.....so I am going to take the carb to the machinist at work Monday and see if he can extract the nozzle and jet. Obviously they are going to have to get replaced.

So, its looking good as far my problem being carb related. I wish I hadn't destroyed the evidence of the uncleaned carbs - I don't think the middle and bottom one ever got touched - I would have considered taking the mechanic to small claims court to get my money back since its fairly obvious he didn't do what I paid him to. I didn't think of it until it was too late, so oh well.
 
racerone - yep, you were right.

Anyway, I bought some replacement carbs last night. The replacements made me realize just how bad mine actually were. Although there is a very small amount of varnished gas in them, there is no corrosion anywhere and they are essentially sparkling clean compared to my old ones.

I had to buy them because I actually cracked the body of my middle carb trying to extract the main nozzle - hence I had to replace it.

I'll let you guys know what happens when they are cleaned up and installed. Thanks for all the help so far, wouldn't have made it this far without you guys.
 
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