64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstances

[tootallofwa]

64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstances

I need to know if the impeller can be checked by removing the thermostat, Before I pull the thing all apart again.

I borrowed a 64' 18hp fastwin from my cousin that wasn't running. He had it in saltwater last time out. It was seized so I oiled the cylinders and breaking it loose was not hard. I rebuilt the carb, repaired the broken fuel pump, shift lever, throttle handle and prop nut. replaced the plugs and wires, fuel lines and sync'd it. Cousin ended up giving the motor to me.

I had it running pretty good but it was leaking gear oil.

I pulled the lower unit to replace the drive shaft seal and impeller. I was plagued by broken bolts, stripped threads and a drive shaft seized to the crank.

Try and try to free the shaft became futile when I realized that the shaft seal was below the the impeller drive pin. The Drive shaft did not budge with a 4' pry bar and vice grips clamped on just below the upper exhaust housing (only the vice grips moved.)

I filed the burrs from the drive shaft I'd made in my efforts to budge it, so it would fit back into the pinion gear. Heli-coiled my stripped bolt holes, hammered flat the impeller plate, installed the new seal, put in a new impeller into the housing screwed it in place and carefully slipped the the the lower unit into place over the shaft. Bolted it back together and started in a barrel. (twice)

I'm not terribly confident the pin is in the impeller because it's not pumping water now (it did before.) But I don't know how it would bolt together if the pin is not in the impeller slot. I was careful to line the pin and water line up before fighting the shift linkage.

I haven't checked the thermostat yet...

Next step is to measure to insure the pin is in the impeller slot. No way to free the drive shaft to assemble the easy way.

Thoughts?

 

[lindy46]

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

So the driveshaft is still stuck in the crank? If that's the case, I don't know how you could reassemble the pump/impeller and be sure the pin was in the slot in the impeller.

 

[HighTrim]

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

Yikes, not a good Saturday afternoon was it!

I guess you had to cut a slot in the impeller housing to be able to slide it over the pin?

If you checked that the cooling circuit was free and clear, the water line is pinched in the grommet, or apart altogether, or there is an issue with the impeller pin.

 

[tootallofwa]

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

Yikes, not a good Saturday afternoon was it!

I guess you had to cut a slot in the impeller housing to be able to slide it over the pin?

If you checked that the cooling circuit was free and clear, the water line is pinched in the grommet, or apart altogether, or there is an issue with the impeller pin.

The housing was kinda over round. I made sure the housing would fit over the pin before I put it together.

I'm gonna have to yank it apart again an measure differences from the exhaust housing flange to make sure the pin will be in the slot after assembly. I was hoping I could pull the thermostat to see if it's pumping but I'm afraid of more worms in my can.

 

[tootallofwa]

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

Re: 64' 18hp fastwin Impeller doesn't pump water after replacement & other circumstan

Got it to pump again!
Thermostat was stuck open. Stole a replacement out of my 40, don't think that was the problem. had to have been that way for a while.

I think the impeller drive pin was too short. I made a replacement out of a nail ground to size. did have to file a notch in the housing for the new pin. gonna be a pain to get it apart again. have to guess when the pin is lined up with the notch or rotate the flywheel while pulling or both.

I don't think the gear oil leak is fixed, the dive shaft has a groove where the seal sets or I boogered it up somehow... Just have to watch the gear case and refill every 40 hours or so. It took it 6 days on the lake to loose its juice before I tried to fix it. Have to retire it soon.

A replacement drive shaft is just not worth it for me. I'd have to pull the visibly rusted powerhead bolts (they're all gonna break) and miraculously separating it from the crank. Oh did I say it's a long shaft with 1 piece water tube. I really need a short shaft.

I plan on rebuilding the 61' Big Twin 40 I've got with the FUBAR piston I started with.

Cheers, Tootall