Mercury Classic 50 service manual and questions

[ImJohnnyKelley]

I bought a 1971 StarCraft Jupiter with a Classic 50 45hp on the back. Love the old boat and have some big plans.



I do have a couple questions and figured you guys could help point me in the right direction.

1. The forward reverse are backwards (have to pull throttle backward to go forward and vice versa). Not a massive deal except there isn't as much room in reverse as forward. Have checked to make sure the cables are correct and going to the right places and that the controls are operating correctly. I am thinking maybe the lower unit wasn't installed correctly. The guy I bought it from just went through the whole thing and it really runs great and is clean, but he even admitted today that it may have been put back wrong. I have seen people talk about the shift rod being in the opposite gear as the lower unit on install and it can mess it up. Doesn't seem to me like it would fully be backwards though. I would expect if the helm was in forward, but the lower unit was in reverse on install that nothing would work as it should or maybe only one direction. But for neutral to work fine, and reverse to be forward and forward reverse just sounds nuts to me. Could that shift rod/lower unit being installed incorrectly lead to my situation?
2. Electric choke on the control isn't working at all. I am in Florida and it doesn't seem like a huge issue right now, but I know I will need it at some point. The manual choke works fine, but from looking at parts online I see that I am missing some of the linkage to make the electric choke work....but not seeing any diagrams of how it goes together (just exploded views of the parts). Would love a pic of the choke and linkages to see what I need to buy and how it goes together.
3. Wanting to get a service manual for it. Looking on Ebay for physical ones, would prefer a digital if there is one though. Any ideas? Also, are the Clymer shop service manuals like the one in the link the kind I want or is there are more technical version I would want? Clymer Service Manual on Ebay. My serial number is 0b258152.

Thanks for all the help. I appreciate it!

 

[Scott Danforth]

Unless you ran out of toilet paper, get a factory manual. Or go to old mercs. I think they have old manuals

Swap the cable to the other side of the bracket at the control

 

[ImJohnnyKelley]

Unless you ran out of toilet paper, get a factory manual. Or go to old mercs. I think they have old manuals

Swap the cable to the other side of the bracket at the control

Swapping the cable doesn't work. One cable is shift and the other is throttle. They both pull when going into forward gear, when going into reverse the shift pulls and the throttle still pushes. If you are meaning to swap the shift cable to enter the front of the controls instead of the rear, there is no set up for that or way to capture and hold the barrel on the cable. Would require some kind of jerry rigging. Would much rather fix what is wrong than to start cutting new holes in the control box to try and try to make something work may not be as reliable.

 

[ImJohnnyKelley]

Welp, it was the lower unit. The last guy did all the needed maintenance on it (new impeller and lower gear oil), but when he put it back in it was in a different gear than the controls at the helm. Pulled it off and got them in sync and now it is working the way it should! Now I just need to adjust the idle a little higher. Won't idle unless I have the high idle lever up. Also gonna get some new throttle and shift cables. This motor was originally on a boat with the helm at the rear and mine is up toward the front so the controls are behind you when you are at the steering wheel. Not great ergonomics haha. But she is running and going into the right gears now!

 

[racerone]

Trouble shooting for running issues starts with a compression test.----Post the numbers here.

 

[ImJohnnyKelley]

Trouble shooting for running issues starts with a compression test.----Post the numbers here.

I would normally start there, but it was running great before I started swapping the throttle and shift cables to troubleshoot the gearing issue. Did a compression test last week and all 4 cylinders were in the mid 140's. Either way, I did an adjustment on the mixture screws on the carbs and it is running tip top again. Starting right up and idling great! Now to replace the shift and throttle cables and I need to troubleshoot the trim tilt motor. I think the brushes are stuck so that is the next job.

 

[QBhoy]

Welp, it was the lower unit. The last guy did all the needed maintenance on it (new impeller and lower gear oil), but when he put it back in it was in a different gear than the controls at the helm. Pulled it off and got them in sync and now it is working the way it should! Now I just need to adjust the idle a little higher. Won't idle unless I have the high idle lever up. Also gonna get some new throttle and shift cables. This motor was originally on a boat with the helm at the rear and mine is up toward the front so the controls are behind you when you are at the steering wheel. Not great ergonomics haha. But she is running and going into the right gears now!

Not sure you should be able to get it into gear with the high idle lever up. Maybe you mean when it’s not running.