1973 Johnson 65 HP Carburetor Question

[kc5hnh]

I've installed the carb kit twice now over the past 10 years in my Johnson 65 HP carburetors. Today I took the boat out on the lake after it had sat up for about 3 years and the motor ran fairly well. (Last time I ran the motor I used a fuel treatment solution and of course, ran all of the gas out of carbs before parking the boat in storage) The problem I've had with the motor is it floods and dies when idling. Cleaning and replacing parts in the carbs from the kits have helped but I still have the flooding when idling/trolling problem. Here is my question. During the carb rebuild, there are about 4 plugs that I have not removed. I believe there are jets behind those plugs. Also, I may have not installed the little spring on the needle valve correctly and may not have made sure then float is adjusted correctly either. Could these issues contribute to the flooding while idling problem? I could sure use some advice. I will probably order the carb kit - 18-7222 soon and try once again to make sure I have the floats and the needle valves in correctly. Thanks for your help.

 

[gm280]

kc5hnh :welcome: aboard. Great to have you join us...

Of course I would buy a new carb kit and using their instruction that come with the kit, remove, disassembly and thoroughly clean that carb again and install the new parts. But for sure remove all the needles and seats and plugs that come with the carb kit. Use a good carb cleaner spray or soak it over night in a carb cleaner setup and some pressurized air to blow everything clean and clear. But make sure everything is clean and all dirt gone. Then adjust everything per instructions and set it back up on your engine. Happy boating if you do it properly... Post back and let us know how everything goes...

 

[kc5hnh]

Thanks gm280 .... I will do just that. It may be a few weeks before I have the time (due to my job) to get it done but I will re-post. This boat has been in the family for 40 years. It still looks pretty good. Had fun on the lake today enjoyed nice boat ride.

 

[kc5hnh]

Since my post on this subject I've had the boat on the water several times and have yet to work on the carb's. Overall, the motor is running great, except when trolling. It seems to be flooding and just a slight toggle with the choke, and the motor will run great. I've had a couple of folks suggest I work with the timing. When I I put it in gear it will immediately die yet, if I put it in gear and quickly advance the throttle like I was pulling someone up on ski's, then it will do just great. This fall I plan on taking the carbs off again and doing what I mentioned above. Then I may do the timing trick and see if that helps too. Other than that, I've burned about 15 gals of fuel through it and have really enjoyed fishing and the boat ride.

 

[F_R]

Set your idle speed up a tad to stop the stalling when you put it in gear.
The nearest thing to "jets" behind the plugs is the idle and intermediate fuel passages under the core plug on top.
Make sure that motor is not ingesting water into any of the cylinders. A known and serious problem arising from a warped baffle plate behind the exhaust cover.

 

[Boat Doctor1]

Did you remove all the "JETS"?? actual jets? not just squirt some carb cleaner thru them?? These will corode & turn a green & stop up. Now as for running the engine to get all fuel out!! That wont ever do it!! In the bottom front of each float bowl- there is a nut/screw- its the drain !! There is also a jet hidden inside there -takes a omc special tool to remove -yes can be removed with a screwdriver!! careful!!!! also on the base / bottom of the high speed pickup tube (center of carb) there is a small round cork/fiber round gasket. That must be there to seal the bown to main body!! see this diagram!! http://www.boats.net/parts/search/BRP/EVINRUDE/1973/65372R/CARBURETOR/parts.html

 

[kc5hnh]

F_R and Boat Doctor1. Thanks for the suggestions. I have not taken all of the jets out. I will do that for sure. I'm sure that once I have thoroughly cleaned all parts of the carbs I may solve the problem. Setting the idle up may help too. I'm pretty sure the carb kit mentioned above is the correct one so I'll be ordering those soon. Thanks again for the information.

 

[kc5hnh]

Here's a 4 min video of my 1973 Invader with the Johnson 65. It really works pretty good, just wants to die when you put it in gear. I'll fix that soon.
https://www.youtube.com/watch?v=i7dvmixj3qM

 

[kc5hnh]

No Title

Follow-up on my 1973 Johnson 65. A friend of mine noticed the play(slack) in the throttle cable and started adjusting the black nut along with the low speed idle screw. (See Pics) After all is this has been done, the motor no longer dies when I put it in gear. We believe that the slack was not allowing the top arm that advances the timing to return back to the idle screw. This was causing the engine to die when putting it in gear. It still tries to 'flood' just a little at long periods of idle but so much improvement has been done with just taking the slack out of the cable. I guess 40 years of use things tend to wear for some reason. haha .. Anyway, took the boat out to a local lake this morning and had almost no issues with idle, trolling, or stalling until I was loading the boat on the trailer. As I was going in and out of gear trying to get the boat to slide up on the trailer, the motor then bogged down some and eventually died. So much improvement at this point that I may not remove the carbs until late this fall. I did buy two cans of Sea Foam and have treated 12 gals of gas with that stuff. I think that may be helping too. Just very happy the motor is performing like it did just a few years ago. Now I'm planning on a serious fishing trip. Too old to do any water ski-ing.
If anyone out there reads this months down the road, and is having similar issues with their Johnson/Evenrude like I did. Try checking the play in your throttle cable. It might just help. Cleaning carbs is still on the menu --- making sure ALL the jets are clean and everything re-installed correctly.

 

[TN-25]

It is worth mentioning that carb synchronization is important on that motor. With 3 carbs it is important that they all shoulder the same load. Remember that each carb supplies the fuel, and with it the oil to lube that cylinder. Any cylinder that doesn't get fed properly also doesn't get lubed!

I don't know if they are common anymore, but a carb sync tool is your friend. It is sort of a vacuum measuring tool. They work well but they assume compression is even in each cylinder. If compression is fairly even then the vacuum should also be so. If they are even then your performance and economy are at their peak.

It is nice to hear that you have one of those fine old 65-horse looper triples that has been in the family for all those years. 1973 was the first year for the next generation Powershift II and also the tilt pin steering that used the Teleflex cable that mounted on the motor transom bracket rather than on the boat transom.