1963 johnson 10hp cooling questions

[crappiejig]

I have a qd-24,new to me, and the spent cooling water exits the motor at just above the lower rubber mounts,from 2 holes on either side of the exhaust housing.Is this normal or is the pumped water not making it to the powerhead? I inspected the impeller,but have not received the new one yet.The cylinder head seemed quite hot after the 2 minute idle run,with a few blips above idle.I am running champion j6j plugs,which looked fine after this short run.The motor has not been run for nearly 11 years.Thanks for any comments.

 

[F_R]

Re: 1963 johnson 10hp cooling questions

Some water escapes the pump housing where the drive shaft goes through. That is the water you see coming out those two holes. If it were not for the holes, the water would go up the driveshaft tube and cause damage to the powerhead. So, it is intentional and perfectly normal.

Now, having said that, if the pump housing is badly worn, a more than normal amount of water would be escaping there. The abnormal discharge is water that could better be used for cooling the powerhead.

 

[crappiejig]

Re: 1963 johnson 10hp cooling questions

So,if I see no other water leaving the engine,thats not right?Typically on my other engines the spent cooling water exits in a stream just under the powerhead. I do not see any other water exiting on this engine,other than that described in the first post.The excess water I saw coming from the pump housing was not very much,just dribbling over the sides with not much psi behind it,so that would be typical of a normal condition. Thank you for your replies F_R

 

[samo_ott]

Re: 1963 johnson 10hp cooling questions

That is not a good situation and you shouldn't run it that way. I have several of the 10hp's and they all mix the outlet water with the exhaust outlet. So where the exhaust comes out should be a lot of water with it. And the engine should not be hot to the touch. Is the paint discolored at all on the head? This is a sign of overheating. If it has not been run in 11 years you definitely need to change the impeller. Also, are you sure you hooked the water tube back up when you first inspected the impeller?

 

[F_R]

Re: 1963 johnson 10hp cooling questions

Wondering out loud here: Are you running that thing in a bucket? It has to be deep enough to submerge the water pump before starting. The pump is not self-priming.

 

[crappiejig]

Re: 1963 johnson 10hp cooling questions

I am not going to run it again without a new impeller and verifying the water tube is in its proper location.I did note the grommet on the water tube was hard and did not seem like it would form a real good seal.The paint is in fine shape on the engine,but I did not note any water coming out with the exhaust. Thx samo_ott for your insight.

 

[crappiejig]

Re: 1963 johnson 10hp cooling questions

Yes f r i am indeed running it in a 5 gal bucket filled to the rim.I thought it would be ok as the inlet screen is submerged,but perhaps your right I do not have the lower unit submerged enough,when I replace the impeller I will have to figure another method of testing,short of hauling it to the lake.But remember,ther is water flowing from those lower holes,which would imply the impeller is pumping? Thx again for your thoughts!

 

[F_R]

Re: 1963 johnson 10hp cooling questions

Those holes are a lot lower than the powerhead, and no exhaust back pressure on the water there. Proves very little.

 

[steelespike]

Re: 1963 johnson 10hp cooling questions

Yes f r i am indeed running it in a 5 gal bucket filled to the rim.I thought it would be ok as the inlet screen is submerged,but perhaps your right I do not have the lower unit submerged enough,when I replace the impeller I will have to figure another method of testing,short of hauling it to the lake.But remember,ther is water flowing from those lower holes,which would imply the impeller is pumping? Thx again for your thoughts!

You need a good big bucket at least 30 gal.I use a 40 gal trash can for my 50
Merc,And adjust the boat so water is at about the same level as when in the water.Basically the can up against the clamp bracket filled to the brim.Normal head temp is too hot to hold your hand on but not so hot it burns you.A delicate dance to test.

 

[crappiejig]

Re: 1963 johnson 10hp cooling questions

fixed!! NEW IMPELLER AND DEEPER barrel.now to get the carb dialed in.i believe i read here that the lo speed starting point should be 1.5 turns out and hi speed three qtrs turn out. thanks to all who helped!

 

[samo_ott]

Re: 1963 johnson 10hp cooling questions

Excellent. So with the new impeller and bigger bucket it's pumping well. Good.