'58 10HP Johnson Bad Lower Crank Seal? QD-19

[petrowski53]

Hey guys,

Started tearing into my '58 QD-19 10HP project to get it ready for spring. I cleaned and rebuilt the carb, rebuilt the magneto (coils, points, condensors, plugs), and rebuilt the lower unit (seal kit and new waterpump with the housing).

The motor fired right up, but would not really reach higher RPMs. It seemed as though the timing may be off, and I'll need to re-adjust the points. The weather has since turned back to winter here in Michigan, so it may be a couple weeks before i can get outside and run it again. I checked to see if it would start and run before I tore into the water pump. The motor did pump water, but I knew the gearcase leaked so I went ahead and replaced the pump anyway.

My problem is, when I pulled the lower unit, the entire inside of the lower leg, including the drive/shift shafts, and water pump housing were covered in a thick carbon sludge. It had a consistency similar to that of used coffee grounds. I'm wondering if it could be a bad lower crank seal, and if that could be why the motor performed poorly when revved. Also, the rubber o-ring at the top of the drive shaft was completely missing, which may also explain the carbon-like sludge.

I know these motors run at 16:1, which can be pretty nasty, but I've never seen the inside of the lower unit, and top of the gearcase, covered in sludge before. Before I start throwing too much money at it, any input would be appreciated.

 

[racerone]

No,---- the mix is 24:1 on those.---Use a timing light to check the firing.--Point it at those 2 vertical marks on the magplate.-----Timing mark on flywheel is always between those 2 marks !----What does a compression test show ?

 

[oldboat1]

24:1 for the 10. Is the motor stored outside (as in a shed or unheated garage)? It sounds a little like ice crystals.

Need some back pressure to tune it.

 

[petrowski53]

24:1 for the 10. Is the motor stored outside (as in a shed or unheated garage)? It sounds a little like ice crystals.

Need some back pressure to tune it.

It's stored in a garage, doesn't get below the mid 40s or so inside. Also, the temp was in the mid 60s when I pulled it. I ran it on the 16:1 for maybe 5 mins or so, and the coating/sludge looked like it had been there a LONG time. I have no idea the history of this engine, I don't think it has ran much in years.

 

[oldboat1]

Could run a compression check while waiting for Spring, if you haven't done one. Sounds like it's got a chance (pretty motor -- '57s and '58s).

 

[oldboat1]

But guess your initial question was on a potential lower crank seal leak. For that, try spraying some carb cleaner around the base of the engine while running (a Spring exercise) -- see if there is a change in rpms. If you pull the l.u. again, you also might look up at the top of the driveshaft with a flashlight -- look for fuel mix leakage.

 

[F_R]

First things first. The oil that you put in the gas goes through the engine where some of it burns but the rest goes out the EXHAUST. So guess what you see if you look up the exhaust housing as you are doing? Yep, oil emulsified with the cooling water that has also gone through and done its job. All this to explain that it is NORMAL.

On the other hand, cold temperatures can aggrivate the situation, making it seem worse than it really is. So can running on one cylinder, which will dump all the unburned fuel coming from the cylinder that is not firing, into the exhaust.

Chances are it is just the cold weather. Enjoy it, it will be hot soon.

 

[petrowski53]

First things first. The oil that you put in the gas goes through the engine where some of it burns but the rest goes out the EXHAUST. So guess what you see if you look up the exhaust housing as you are doing? Yep, oil emulsified with the cooling water that has also gone through and done its job. All this to explain that it is NORMAL.

On the other hand, cold temperatures can aggrivate the situation, making it seem worse than it really is. So can running on one cylinder, which will dump all the unburned fuel coming from the cylinder that is not firing, into the exhaust.

Chances are it is just the cold weather. Enjoy it, it will be hot soon.

That's kind of what I had figured, I've just never seen one so sludgy!

I bought if off of a guy who really didn't know much about wrenching, let alone outboards, and could never get it running. It seemed to have the original coils, as they were both badly cracked. It very well could have been running on one cylinder in the past, which would explain the excessively rich exhaust.

Overall it's in really nice shape, still with somewhat glossy original paint. Its pretty apparent that nobody has tore into this motor before, which is fine by me. I'd much rather deal with overdue maintenance and replacement parts, then have to correct somebody else's misguided repair attempts.

I think the '58s really are the classiest looking Johnson's, I can't wait for it to warm up so I can take her out and get her tuned nicely!

 

[F_R]

Besides all that, on that motor the drive shaft and end of the crank shaft run in a tube, isolated from the exhaust. So even if the lower seal that you are concerned about is leaking, the leakage would go down the isolation tube, not down the exhaust cavity.

I agree, it's nice to find one with shattered coils, which means it hasn't run in a long time, and may be unmolested. Good luck with it.

 

[oldboat1]

Chances are just tuning issues. Wires are the solid core type, not automotive wires. Here in NY, I found some at the local NAPA (7mm). I think it's used in some cycles and period tractors -- hobby activity with both up here.

You probably know this stuff, but the connections at the coils and the spring connectors in the plug boots have to be solid -- small thing, but can save a lot of troubleshooting frustration.

Eating Florida oranges here, but giving the snowblower a workout. Not so bad on balance.

(motor pics always welcome if you get around to it sometime.)

 

[petrowski53]

No Title

Chances are just tuning issues. Wires are the solid core type, not automotive wires. Here in NY, I found some at the local NAPA (7mm). I think it's used in some cycles and period tractors -- hobby activity with both up here.

You probably know this stuff, but the connections at the coils and the spring connectors in the plug boots have to be solid -- small thing, but can save a lot of troubleshooting frustration.

Eating Florida oranges here, but giving the snowblower a workout. Not so bad on balance.

(motor pics always welcome if you get around to it sometime.)

I do have a couple of pics from when I first picked up the motor(s). I answered an ad for the '58 10hp, and ended up getting the '58 QD, plus a '56 7.5hp AD-10 that looks spotless under the hood. He also threw in a pressure fuel tank, all for $100 bucks!

Here are a few pics

 

[oldboat1]

Thanks for the pics -- look like nice originals! Great price. Like the idea of folks passing along old classics without trying to finance a new RV.