in-line 6 overheating problem - Page 2

spareparts · #11 03-03-2011, 08:56 PM

the water pump in those drives is a weak point, they only have to run dry for about 20 sec before they are damaged, they will also get brittle and break the blades off if they sit for long periods of time. Go ahead and drop the lower unit. Do a search on utube, there are probaly several videos of people doing a water pump on a mercruiser(I'm going to make a video of it one day), i'll give you two hints, drain the fluid out first, and put the gear shift in fwd gear before you drop the lower. Between Ferm, Skools and myself, we've probably explained it 30 times on here, do a search for water pump replacement

moneyhole · #12 03-03-2011, 09:26 PM

Thanks....been looking at all the video feeds I can find on the internet. The manual's pictures are very hard too make out. Wish thet were in color instead of B/W.

moneyhole · #13 03-03-2011, 09:46 PM

When I put the prop & water intakes into the tub of water and ran the engine for about 2 mins, while watching the temp gauge, I noticed about a 1/8 or less handful of rust particiles from the prop exhaust. Got to thinking, if I see this much rust from a boat that has a new used engine swap but & only 7.5 (not 3 as previously stated) hours, what else am I going to find?
My biggest question is , should I fill the antifreeze tank to full and put the tub or water muffs back on and try running it again? Or should I just order a lower unit stern drive water pump assembly rebuild kit? What kind of bill would I expect to see from a boat shop --- labor wise, since I already know the impellor parts price

moneyhole · #14 03-03-2011, 10:02 PM

Spareparts, what are the most important things I need to pay special attention to when dropping the lower unit and making the repairs to correct my water intake flow problem? Any special tricks/tips I should be aware of?
Thank you for your help.
Do you & Destroyer feel this is most likey my problem?
** Note - My boat pics are on my profile page

moneyhole · #15 03-03-2011, 10:19 PM

Destroyer,
That's where I'm lost. There was no water at all in the 3" round tube and no water in the manifold when I opened the drain. I do know they used the old engine's thermostat when the swapout was done. Could I have dual problems.... engine T'stat not opening at set temp and have a bad stern drive water pump impeller pump at the same time? I'm just speculating at this point. Thanks again for any knowledge shared...it's making me crazy

brisboats · #16 03-04-2011, 08:41 PM

If you pull the inlet hose like I told you you could see if the lower unit pump is working. Like most have said it is probably the raw water pump, buy one and install it for good measure if it hasn't been done in awhile.

I have never seen a 3" exchanger on an inline six. You have any pics of this motor?

moneyhole · #17 03-04-2011, 09:21 PM

There is a pic of the motor on my album page, but you can't see the 3" round exchanger too good in that pic. I did measure it and it's 3" in diameter. I bought a complete stern water pump kit today...drained the lower unit just before the sun set and the grease/oil most lilely had water in it. It has that funky smell and is olive colored. If I reading the manual correct, I should be able to pull the lower unit without removing the prop. We'll see how it goes and pray for sucess!!

moneyhole · #18 03-05-2011, 01:09 PM

I see now why my water pump is bad, as I was taking off the lower unit I noticed some areas that had been epoxied and painted over. Guess what, the whole trim tab casting on the upper half of the motor broke off. I traded the boat with a horse trader. Can this type of "pot metal" be welded or am I just up the creek wihout a paddle. I'm going to post a pic of it in my album. If any one has any ideas, suggestions, solutions or other ideas

than sinking her, let me know. I've contacted the fellow I got the boat from asking to reverse our trade...doubt I get far with that one. Live & learn.

spareparts · #19 03-05-2011, 01:17 PM

they weld on those lower units all teh time, just find someone whos familure with the repairs, try a prop shop

moneyhole · #20 03-05-2011, 01:30 PM

Thanks - was hoping it could be welded, but it burns my rear knowing this guy sold it to me like this.....very good lesson learned..buy a boat on a warm day and insist the owner take you out for a test ride. Ha! I'll call on some old buddies that have welding experience and see who they can recommend. I guess it's time for a cold one and wrap it up in plastic.
Thanks again SP....this is a really great site!!!!!!!