Johnson QD-19 Shift Rod Problems

[lightwin]

Just acquired two Johnson QD 19's in a one week span. The first is seized but I picked it up for parts in anticipation of the second QD 19 that mostly runs. The second has a broken shifter rod but otherwise runs well. Turns out both the upper and the lower shifter rods are in bad shape and severely corroded. My initial plan had been to simply take the shifter rods from the parts engine and install them in the second but the level of corrosion on the rods is troubling me. Is this an indication of something else wrong? The water pump and drive shaft are in good shape and the top and bottom end of the shift rods are pretty clean as well but the middle section, by the access panel, are brittle and half the original width. The bolts in the connector are unrecognizable as well. Should I alter my plan from just swapping the rods to swapping the whole mid section of the engines?

 

[samo_ott]

Re: Johnson QD-19 Shift Rod Problems

Interesting. I have never heard of that level of corrosion. You don't say where you are but is this a salt water environment? As the lower unit is sealed (did you drain and check the oil condition?) I see no need to change it all other than the shift rods. But to change them it is a lot of work. For the upper you need to remove the powerhead and for the lower you need to drop the skeg and remove the prop shaft so probably just replacing the entire LU would be easier.

 

[lightwin]

Re: Johnson QD-19 Shift Rod Problems

Yup. Salt water. No matter what I do it is a lot of work. Both ends at the connector are shot. The lower end of the upper rod broke off in the connector and the upper end of the lower rod is less than half the original thickness. I have them both out and on the bench and the replacements from the other engine removed and ready to go in (yes there are a lot of parts on the bench). I am now hesitating to put them in out of fear that I am missing a problem that could lead to this again. As far as I can tell there are no issues though the gasket at the view port must have been bad. I don't want to do all this only to find out I should have gone with another mid section.

 

[samo_ott]

Re: Johnson QD-19 Shift Rod Problems

There is always water inside the lower housing as it come from the engine after it has been used to cool it and then gets dumped out underwater. There's no way around it. All you can do is put it back together with the best parts you have and hope it will last another 53 years!

As an FYI, the QD19 was known to have weak lower units. As in 1958 they changed the lower unit from the 5 bolt lower unit (shared with the 18hp's) used in '57 and earlier to the weaker 4 bolt lower unit (shared with the 5.5 and 7.5hp's). I have many QD-19's in my shed with failed lower units unfortunately. So I hope yours is good. Check the bushings in the lower unit to see if they are still good. Check the one specifically where the pinion gear sits. As well as check all the gear teeth and clutch dog.

 

[F_R]

Re: Johnson QD-19 Shift Rod Problems

I have seen lots of RD's with eaten-up shift rods, but can't remember ever seeng a QD with that problem. With the RD ist is a combinaton of water and corrosive exhaust blowing on it. But like I say, a QD?? that's a new one on me.

 

[lightwin]

Re: Johnson QD-19 Shift Rod Problems

There is always water inside the lower housing as it come from the engine after it has been used to cool it and then gets dumped out underwater. There's no way around it. All you can do is put it back together with the best parts you have and hope it will last another 53 years!

As an FYI, the QD19 was known to have weak lower units. As in 1958 they changed the lower unit from the 5 bolt lower unit (shared with the 18hp's) used in '57 and earlier to the weaker 4 bolt lower unit (shared with the 5.5 and 7.5hp's). I have many QD-19's in my shed with failed lower units unfortunately. So I hope yours is good. Check the bushings in the lower unit to see if they are still good. Check the one specifically where the pinion gear sits. As well as check all the gear teeth and clutch dog.

Thanks. I have taken both lower units apart and they both had old but water free oil in them. All the gears, etc. are in good shape though the skeg of one looks to have been reattached with an epoxy of some sort after a collision. That one will land in the last resort parts pile. I guess it doesn't seem to matter about the rods being rotten. Sounds like it just happens. I will stick with the best parts and hope it doesn't happen again.