starts great, idles great, but dies when in gear

[heyitstim]

I JUST CAN'T SOLVE MY PROBLEMS WITH MY 74' 65HP MERCURY. It starts great, no need to choke it, it even idles great. You can use the warm up lever and thottle it way up as if it going to explode but when I put it in gear it just starts to die down the more gas you give it the worse it runs till it dies. I just rebuilt the carbs, so if the problem is them tell me what I did wrong or what I need to do to fix them. Thanks Tim

 

[Reel Appeal]

Re: starts great, idles great, but dies when in gear

Hi,<br /> Maybe too rich a mixture on the carbs.If there is an adjustment screw try turning it clockwise a little bit.Your motor should not start(when cold)that fast without a little choke involved....Are the needle valves(in carbs)in good shape?floats?Good luck...

 

[rickdb1boat]

Re: starts great, idles great, but dies when in gear

Check fuel lines and primer bulb first. Does the bulb stay hard when you pump it up? Does it stay hard or flatten out when you're running? If that's OK, Then I would rebuild the Carbs! As Reel Appeal said, you float needles or something else is causing your problem, which only a rebuild will solve. As a side note, never run your Motor at that high of RPM'S in neutral. You will destroy the Motor quickly!

 

[heyitstim]

Re: starts great, idles great, but dies when in gear

I guess what I don't understand is why will it idle so good or rev up when in neutral but when you put it in gear it will die out. The fuel line is new and the bulb is to. I put new fuel lines from the front of the motor all the way to the carbs. The needle in the two carbs are fine, no sign of wear. Do I need to turn the idle screw clockwise to close down the needle or up it up more. With the motor cold it starts without the choke easily. I rebuilt the carbs following directions from the seloc manual. The idle screw is set at 1 1/2 turn open from closed. Where do I go from here? Thanks guys for all the advice. Tim

 

[rickdb1boat]

Re: starts great, idles great, but dies when in gear

The only other thing I can suggest at this point is to Check for good spark to all cylinders and do a compression check.

 

[rickdb1boat]

Re: starts great, idles great, but dies when in gear

Also, many engines will seem to be fine when run in neutral without a Load on them, but once in the Water, they won't go! As I said, you may not be hitting on all cylinders!

 

[Steve135]

Re: starts great, idles great, but dies when in gear

heyitstim - You didn't say why you rebuilt the carbs in the first place . Was this the reason it stalls in gear? When did it run best last? If it had been ok and it started to act up all of a sudden I would have looked else where first, other than fuel. If it only happened after the rebuild thats different too. Also are you doing this in the water or out of the water This makes the answers different too! If its happening in the water check to see the timming is advaceing when it gear. There might be a lack of lube on the spring on the arm or a build up of salt yuck! Give a better history of the problems prior to the event.<br />steve

 

[heyitstim]

Re: starts great, idles great, but dies when in gear

Two years ago I had to store the boat in a garage. It was an unexpected event that caused me to not use the boat. It had been running great up till then, this summer was first chance I have had to run the boat since that time, the bottom carb had gas running out the front of it. I could not get it to run. I assumed that the float was stuck or had a hole it. Tried tapping it, didn't work. put cleaner in it, didn't work. Took advice that a rebuild was needed. I did that and now it starts great, idles great but when you put it in gear and give it gas it starts to die out, I feel that I will have to remove the carbs again and look for some blockage, I feel I did a good job on the rebuild, what the problem was, it had a stuck float caused by the gas that was left in the carb during storage. If I can make an adjustment without taking carbs back off tell what to do. My manuals don't really have a trouble shooting section, it says to take to an authorized repair center. $45 AN HOUR, I'm looking for an alternitive. Thanks Tim

 

[ob]

Re: starts great, idles great, but dies when in gear

Assure that your carb flaps are syncronized.Full throttle position all should be evenly horizontal.This is rough adj. check.To fine set everyone has their own method.I like to open from full close at various positions and measure open gap with precision tool.I use small hole guages for this and it assures me of almost exact opening gap on all carbs at various throttle settings.The other thing you will have to determine is when your carbs begin to open in relation to ignition timing.This on some motors has a factory scribe mark on throttlle cam in relation to carb linkage roller.This is generally checked in nuetral throttle position.On many ,factory sets it up where the centerline of roller is aligned with scribe line on throttle cam.Hope this helps.Also,when in nuetral position check to see if all carb flaps are fully closed.

 

[rickdb1boat]

Re: starts great, idles great, but dies when in gear

I would still take the Carbs back off and double check, since that was the only thing you did since it last ran good! But check out OB's suggestions first!

 

[wboard1979]

Re: starts great, idles great, but dies when in gear

i'm just a rookie, but my friend had an experience just like that. we thought it was the carbs (86'evenrude 90hp)so we got them cooked for 4hours tryed again same problem,ended up being cracked coil and sparkplug wire boot was cracked. it was grounding out on the couling latch. just an idea remember im just a rookie.

 

[fshng4]

Re: starts great, idles great, but dies when in gear

Before you go to all of the trouble taking off your carbs pull your plugs and do a compression check. All should be within 6% of each other. This will tell you the condition of the motor internally. Next check for a good strong spark to your plugs and then for a good spark at the plugs themselves. Also check to make sure you do not have any stray spark under your cowling due to a break down in your plug wires or sparkplug boots. Put the muffs on the motor or take it to the ramp after dark - start the engine - pop the cowling and start looking around at your plugs and wires (darkness really helps). Take a screw driver and a wire jumper with an aligator clips on both ends - clamp one end onto the motor block and the other end to the screw driver - begin rubbing the screwdriver over each of the wires and boots about 1/4" away - if you have a spark leakage it will jump to the screwdriver (this is best seen in the dark and make sure you do not have any gasoline laying under the cowling that might ignite). Had similair problem with a 115 Yamaha turned out to be a bad coil along with a bad sparkplug boot. Look at this way Compression - Spark - Fuel. Just my thoughts.

 

[heyitstim]

Re: starts great, idles great, but dies when in gear

Took the boat to the lake to try to work on it in the water. After adjusting the idle screws on the motor I was able to get it take gas and run up to a good speed. I believe that was the biggest part of my problem. Still have some other adjusting to do, will let you know what happens next. Tim