Cooling Question: SOLVED!!!

[kwoolard]

Re: Cooling Question: SOLVED!!!

Great.........just in time! I was hoping to get this thing ready for 4th. I was in the same situation last year, trying to get ready for the 4th. Oh well! <br /><br />I'll put the outdrive and check the bellows, if no water in the bellows I should probably pressure check the lower unit right?

 

[Haut Medoc]

Re: Cooling Question: SOLVED!!!

Lower & upper....I'll be real suprised if your bellows are clean.....J

 

[kwoolard]

Re: Cooling Question: SOLVED!!!

If they are clean, which they were a few weeks ago when I replaced them and the bell housing, would you suspect the water pump seal or the prop seal? I guess I just need to pressure check and see.

 

[kwoolard]

Re: Cooling Question: SOLVED!!!

One more thing. On the pre-alpha's with the pre-load pin, as I have, isn't there supposed to be a o-ring seal at the top of the drive shaft to keep water from getting on the splines? Will that get water in the gear case?

 

[Haut Medoc]

Re: Cooling Question: SOLVED!!!

I don't know the answer to that one...Has the boat been sitting in the water or out?

 

[kwoolard]

Re: Cooling Question: SOLVED!!!

Out of the water. I'm thinking either a dry rotten drive shaft oil seal or prop seal. Won't know til I investigate.<br /><br />Thanks for all your help so far!

 

[Haut Medoc]

Re: Cooling Question: SOLVED!!!

If its been out of the water for the whole time, I would look at the water pump base. Have you pressure checked it yet?

 

[kwoolard]

Re: Cooling Question: SOLVED!!!

Finally! The overheating problem I have been having for the past year is solved. It turned out to be the water pump that was supposed to be replaced by a local mechanic. You can bet he won't see a dime of my money or anybody else I know again!! I should report him to the better business bureau. Oh well, lesson learned. The temperature ran about 145-150 at idle and up to about 3000 rpms, at about 3600 rpms for about thirty minutes it would slowly climb to 175-185 and hold there. All these temperatures are with a 140 degree thermostat installed.<br /><br />As for the gear oil, I refilled with the Quicksilver gear lube and checked the level and color after both days of hard running this weekend. The level and color stayed the same as when I filled it. So hopefully it was the water pump base seal that was leaking, it was in pretty bad shape. <br /><br />At least I got to enjoy it with friends and family for the holiday weekend. Thanks to all who have given me a lot of input on this subject! I just hate to see that it was a shady mechanic all along.

 

[Haut Medoc]

Re: Cooling Question: SOLVED!!!

Glad to hear you got it solved, I know you've been tearing your hair out for a long time over this. Just shows you that the more you can do yourself the better off you are...... I would have some choice words for that guy....Jeff

 

[gspig]

Re: Cooling Question: SOLVED!!!

kwoolard, you say the gasket under the pump housing was leaking? I had the exact same problem on my pre-alpha outdrive this year. I had also paid someone to replace the entire pump. How did you find the problem? I found it only after putting the water muffs on the opened lower case and saw water spraying from under the pump. My pump would cavitate when I got on plane and the engine would overheat. I ruined 3 impellers before I found the problem.

 

[kwoolard]

Re: Cooling Question: SOLVED!!!

I installed a clear hose from the transom to the thermostat housing and noticed some air bubbles in the line while up on plane. I also noticed that the flow was not all that great. When I took the pump apart, not to my surprise the impeller was dry rotten, cracked and the fins had a lot of curvature to them. When I drained my lower unit oil there was a milky mixture so I knew water was getting. I noticed that the oil seal on the lower pump housing was in bad shape. The lip of the seal was gone, so I assumed I was pumping some water into the lower unit passed that seal and could also have been pumping some of the gearcase oil up the water line. That would have explained my oil level in the gearcase for being so low. I replaced all the gaskets and both the upper and lower housings, and my oil shows no signs of water intrusion anymore. I hope that solved the water in my oil issue, it definitely solved my overheating.

 

[yoced]

Re: Cooling Question: SOLVED!!!

Most awesome. So glad that you finally got this thing licked. You have shown some most excellent stick-to-it on this one K., and deserve some well earned boating.

 

[kwoolard]

Re: Cooling Question: SOLVED!!!

Hey guys, sorry to keep beating this subject up but I wanted to gets some opinions on my current operating temps. For the past couple of weeks of running the boat she is holding a steady temperature at high running speeds (3400 rpms) of about 190. This is with a 140 thermostat installed. When I first took it out after solving my problem it was holding about 175-180 at the same speed. It has slowly crept up and I am wondering if I could be getting some scale buildup in the risers? Also, with that initial run of 180 degrees isn't that still a little to high with a 140 thermostat, do you guys beleive that it could be a circulating pump failing, just a lot of scale flakes in the block, or the motor's internal cooling passages are so old that it is going to run this hot?

 

[kwoolard]

Re: Cooling Question: SOLVED!!!

Any comments?

 

[Haut Medoc]

Re: Cooling Question: SOLVED!!!

Still battling the beast, huh? I think that all of the answers are 'yes'...However I don't think 180 is over-heating, just warm. Any hotter though...I thought the circulation pump was checked last year. How old is it? They usually don't go bad,.ie the vanes rotting off, before they leak. The pump should be easy enough to get at. For the time and the price of a gasket take it off and look, just to eliminate it from the equation.The only way to answer the riser question is to yank them off and see as well. I bought a boat with raw water cooling a long time ago, and changed the manifolds/risers but I would still get scale from the block, and would have to take the risers off periodically to get the crud out of the water dumps. Hope this helps......JK

 

[ziggy]

Re: Cooling Question: SOLVED!!!

kw, i feel for ya, but it does sound like yer closeing in on the problem. i had cooling issues this year also. turned out to be my impeller too. but while i was there, (replaceing the impeller) i was flushing out my old impeller pieces backwards and forwards from the water tube that goes between the upper and the lower and the t-stat housing. i had a gasket leak at the waterpocket cover while flushing from the t-stat back twards the water pump. it was suggested to me at the time (by achris, who was instumental with helping me fix this problem)that since i had a gasket leaking water at the water pocket cover, that it could also introduce (leak) exhust gases into the cooling system too. thereby causeing a possible overheat condition. i know ya said the water pocket cover looked good. mine did not, it was heat warped and somewhat blistered looking. but i thought that it made sense to tighten up the waterpocket cover screws and be sure i didn't have a leak there. once again i found this gasket leak by flushing water from the t-stat backwards and letting the water just run out of the water pocket tube, upper and lower seperated. i could see the water leak easy around the water pocket cover gasket. if ya think ya have this problem, be very carefull when tighting the screws or loosening them on that waterpocket cover. i broke 3 of mine off. 20 hours later they were helicoiled. <br />as for yer upper o-ring on the driveshaft. my model 1 had the o-ring. but i left it off on purpose per suggestions here with no ill effects as of yet. <br />one last thing. i did replace my riser and manifold. but i had known welding issues with my manifold. from best i can read, cleaning them is only a kinda fix. if there is any question about them, i'd just replace them and get them out of the equation, they seem to be almost PM on a boat.........