Seeking Johnson carb advice

[cberkau@yahoo.com]

93 Johnson 60HP CD3; Model T/J60TLET/D, S/N G03265019<br /><br />This is a fabulous forum with excellent people and resources. Used it before but appears my login got stale. Have great respect for Mr. Joe Reeves among others who've helped me in the past.<br /><br />My son's boat is having diffugalties. I've researched the forums and read excellent tips, tests and tricks - about everything I could find - on carb cleaning & rebuilding, and symptoms. Excellent stuff from 12Footer (Carb 101) and the gentleman's article on cleaning (sorry; forgot the name). Other posts have been great as well, and I've about decided on rebuilding the carbs, but wanted a 'gut-check' from you great folks before doing so.<br /><br />Symptoms: First noticed after skiing for 45 minutes when returning home running WOT and it just dropped power down to 1/4 or idle power, and seemed rough. Checked prop, no debris or fishing line, seems OK; didn’t hit anything. Almost acts like S.L.O.W. was kicking in. Peeing OK; not too hot to the touch.<br /><br />- Gas and oil is fresh – 93 octane.<br />- Can’t get back up on plane.<br />- Checked plugs – OK (put new ones in, old ones were clean, a little oil maybe). No change.<br />- Compression ~120 on all three cylinders<br />- Checked spark with timing light at idle; all looked consistent, even while revving. Didn't check under load.<br />- Checked resistance of temp sensor: ~ 9 megohms (when engine off). Didn’t unplug it while running. Doesn't seem hot; peeing well; and same symptoms cold. Changed LU oil about 2 months; rebuilt water pump about a year ago (~100hrs).<br />- Checked fuel filter, seems OK, clean<br />- Changed fuel line & bulb; no change.<br />- Fuel line into pump seems like it’s not drawing while holding finger over intake & cranking.<br />- Noticed while running and bogged down, if you push in on the key, seems to vary the RPMs +/-100.<br /><br />After doing all the stuff above, my son took his boat to a shop. They checked it out in the shop and said all looked good; needed a water test on the lake to find out more. After that, said the carbs need to be rebuilt. It's already $150, and it'll be another $300. We don't fault the shop for the price; my son just doesn't have the cash and Dad (me) won't pay for it. I'd rather get an OEM manual, kits and help him rebuild them over the weekend. Seems straightforward from all the wonderful insight here.<br /><br />Plan is to get a factory manual and rebuild the carbs and do the fuel pump at the same time. What I respectfully request from you folks is to let me know if we've missed something dumb or any other words of advice regarding the carbs or fuel pump. <br /><br />Great place, people and resources. I really respect the insight from all you folks. Thank you very much in advance for your help. <br /><br />Best -<br /><br />- Chuck<br /><br />(Sorry for the long post.)

 

[angus63]

Re: Seeking Johnson carb advice

Chuck<br />Was this a one time thing or has it happened in the past? Is it still happening now or will it get up and go now? Compression is good. Did you check spark gap (7/16" with a good white SNAP)? Did the rpm's pickup when you pushed the key in? What was the condition of the fuel bulb when this happened? What plugs and gap are you using? What fuel and oil are you using? VRO? How fresh is the fuel? Has the fuel pump supply/pressure been checked? Have you tried running from another tank? If you spray a little premix in the carb throats, does it pickup? Is the tank vent open? That's enough for now.... Let us know<br />Good luck

 

[cberkau@yahoo.com]

Re: Seeking Johnson carb advice

Hi Angus,<br /><br />It's constant now, hot or cold. I was driving when it happened at WOT. Tank vents opened when it happened and since. VRO disabled. Changed tanks, fresh 93 Octane with fresh Pennsoil TCW/3. Bulb and line was old and line was hard, so we changed 'em; no help. Pumping during running didn't help. Haven't checked pump supply pressure; no vac gages. Seems I remember from previous (~2 years) more suction on fuel intake to pump when cranking than now. Only checked spark w/timing light during idle. Put new Champions (gapped right) in, no help. <br /><br />RPMs changed slightly (I'm guessing ~100 RPM) during running when key pushed in/pulled out. Sprayed carb cleaner in carbs, and a little starting fluid while idling, but not premix, nor while while running under power, bogged a little as I recall. <br /><br />My son just retrieved it today. I can check the spark but believe it will be fine. Starts fine, idles fine... just no hole shot or WOT. Like it's SLOW limited all the time.<br /><br />Thanks for your response. What do you think?<br /><br />Chuck

 

[angus63]

Re: Seeking Johnson carb advice

Sounds like a float might be stuck open. Sometimes a light tap from a screwdriver handle will free 'em. More likely you'll need to drop the bowls, clean, inspect needle and seat, set height, and assemble. If you plan to do your own work, I highly recommend a factory service manual. Try www.theoutboardwizard.com for the manual and any OEM parts you may need.<br />Does your warning horn work? Have you tested? If it was is SLOW, it would reset after turning off key and restarting.

 

[angus63]

Re: Seeking Johnson carb advice

One other thought, have you inspected the plugs after this occurs to see if there is a visual difference (wet,dry, burnt, chalky, steam cleaned, etc...)?

 

[marinemech1]

Re: Seeking Johnson carb advice

test warning horn turn on key ground out brown lead from head. horn should sound if it did not motor could be in s.l.o.w. fix horn first<br /><br /><br />2nd idea look at linkage make sure timing moves with throttle advance especially link under flywheel is connected<br />make sure all carbs advancing to wot look at roll pins in throttle shafts all should be vertical at wot<br /><br />3rd idea ground out ignition one at a time to all three cylinders... if you put nails in plug boots its easy to ground ignition just be sure to use a insulated screw driver

 

[JB]

Re: Seeking Johnson carb advice

Lots of good advice above, Shade Tree.<br /><br />Before you do anything else, determine whether it is spark or fuel that is being denied one cylinder.<br /><br />With the engine at idle, (carefully) disable each plug wire, one at a time. The one that doesn't affect the idle is the dead cylinder. Check for spark. Got spark? Spray some premix (NEVER ether) into the carb for that cylinder. If she perks up you have a sick carb.<br /><br />If the dead cylinder has good spark and doesn't pick up when fuel is sprayed, you will need to inspect the reeds and bypass covers.<br /><br />Good luck, and let us know what you find.

 

[cberkau@yahoo.com]

Re: Seeking Johnson carb advice

Thank you all for the great advice. I'm looking in to ordering factory manual now.<br /><br />We'll do as advised above as soon as we can get her in the water, and let you know what we find.<br /><br />Thanks again to all!

 

[Dhadley]

Re: Seeking Johnson carb advice

Theres a couple of things to perhaps look at before going any further.<br /><br />You said the plugs are new but you didnt say which ones they are. Make sure they're Champions. If not they may not be the right heat range. Not good.<br /><br />Then, get back to the recommended 87 octane. Ronning the 93 may increase combustion temps. Again, not good.<br /><br />Clean the carbs before you run it anymore. If the carb(s) are partially gummed up there could be a problem with one or more cylinders running lean. It sure sounds like it. Not good either. <br /><br />Remember, your fuel is carring the oil. If you run lean on fuel youre running lean on oil. Pistons dont like that.

 

[cberkau@yahoo.com]

Re: Seeking Johnson carb advice

Good Afternoon Folks, here's a little update:<br /><br />The warning horn works as advertised.<br /><br />I'm still leaning towards rebuilding them, Dhadley. Sprayed carb throats with carb cleaner before it went to shop, they looked clean before I did that and still look really clean, but that's only what I can see with 'em on. What else can I do besides rebuild... Sea Foam and decarb it? <br /><br />I'll get back to 87 ASAP. Guys at the shop told my son he should run 93 all the time, but I'm with you. That thing's always run fine without it. In fact, it ran fine until 93 went in it, and after about 2/3 of the first tank is when she started acting up. Could this be the whole problem? It did run good for that 2/3, until running back at WOT she just sputtered down like S.L.O.W., and has never been back up.<br /><br />Plugs: The set that was in when this first happened were NOT Champions and were black with a very little bit of fuel/oil, but I thought they looked OK. First thing we did was put in new Champion L77JC4’s gapped at .030 and tried it in the lake before he took it to the shop; no change. I just now pulled ‘em, and they look a little tan (chalky?) and dry. I recall Joe Reeves telling me the Champions should be gapped at .040 for this engine, so I re-gapped for .040. Good strong white arc at 7/16” on all three with a spark tester.<br /><br />The roll pins are at about -10 degrees, not strictly vertical at WOT, if you get what I’m saying. The butterflies are almost wide open, but not quite. <br /><br />I only had the muffs on her, so I couldn’t run at WOT. The problem is I can't get above about 2K anyway, so WOT under load isn't doable, yet. (It’s 12 miles to the public ramp, now that they’ve dropped the levels for hurricane season, & I'm not sure I'd have the "oomph" to get her back on the trailer if I took her off). At idle, she's -4, or 4 degrees ATDC. As much as I did rev her she advanced to about 0 to 1 ATDC. Sticker on the noise cover says 19 BTDC. The paint mark on the flywheel is about 18-19 BTDC.<br /><br />Idle seemed a little high. Noticed the idle stop screw isn’t engaged by about 1/8”; it appears the screw isn’t long enough, as it’s bottomed out (much shorter than the WOT stop screw). All we have now is a Clymer book until the factory manual comes in (ordered book & 3 carb kits from outboardwizard, Angus ;o). I’m a little goosey about going thru the whole tune up with Clymer, as photos don’t correspond to reality; they’re typical examples, as they say. I hope factory is a little more precise.<br /><br />She idled OK at first, but after about 5 minutes, she’d miss about every 5-7 seconds, with a jerk. Pulled each wire and noticed a consistent, distinct miss that went away when reconnected. #2 was a little smoother of a miss than 1 or 3, but missed just the same. Squirted fuel/oil mix in each; it'd bog then come back. #2 definitely came back smoother for about 10-12 seconds, then back to funky missing. That go with what you're thinking, JB?<br /><br />Thanks again to you all for your help, suggestions and insight. It is very much appreciated by my son and me. You folks are top shelf.<br /><br />Best-<br /><br />- Chuck

 

[Dhadley]

Re: Seeking Johnson carb advice

It might be a good idea to take compression since we've ran the motor with some issues. Just to have a good reference point.<br /><br />The carbs should be disassembled and soaked. Then reassebled with new kits. Spraying cleaner down the throats will help get the rings cleaned but thats basically by-passing the carbs. We need to get the passages inside clean.

 

[rayjay]

Re: Seeking Johnson carb advice

When you have the carbs off look into the reed blocks to make sure you don't have a damaged reed. Since the motor was running good and then instantly started running bad before pulling the carbs I would drain the carbs into a container to check for water.

 

[angus63]

Re: Seeking Johnson carb advice

Just another thought..... I believe that motor needs "Q"L77JC4 plugs for the iqnition system. Q type plugs are suppressor (sp?) type that prevent leaking spark from messing with the ingnition system. Dhadley, compression is initial post looked great. Good compression, good spark, all plugs look equal, fresh fuel (use 87 octane), and all cyls firing are all pointing towards carb problem (most likely). When cleaning carbs, wipe down plastic parts, soak metal parts, and blow out every nook and cranny with clean compressed air. Your gettin close to the solve.....<br />Good luck

 

[cberkau@yahoo.com]

Re: Seeking Johnson carb advice

Thanks to all you kind folks. I've got the carb kits and factory manual on order and should get them next week. I'll let you know how we make out.