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jsonova99
06-19-2011, 05:12 PM
Okay, started my boat for the first time, started right up, but in the middle of fooling with some things, I noticed that my fake a lake had slipped and to make a long story short, the raw water pump got hot and shredded the impellar. Put a new impellar in with fake a lake on correctly, but no suction. I keep finding bits and pieces of the old impellar in the lines, could it be clogged? I would assume if I fried the bearing in the pump it would leak, but still suck up water (had this happen before). This pump is only 2 seasons old. I get absolutely no suction whatsoever. Worked fine the last time I ran it last season while winterizing it. What if something froze on me (first winter for this boat, just moved up from Florida). I would still think you would get suction, but again just end up with a leak.

My current troubleshooting locations are:
1) burned up pump
2) clogged intake
3) leaky intake hose (although I would still think you would get suction, just that you would also have water leaking)

Thanks in advance for any help. I'm going to keep picking the lines to see if there are any other big bits of impellar clogging it up

Jorski
06-19-2011, 09:49 PM
Start looking for all of the broken impellor pieces.

Jerseydave
06-19-2011, 10:23 PM
check your trans oil cooler....it might be clogged with pieces of your old impeller
Remove the hoses off each end of the cooler and with a garden hose spray water in the opposite direction of normal flow to backwash the cooler.

BTW, I'm not a big fan of the fake-a-lake (especially when they move out of place like yours did) I use a 5 gal bucket with a hose connected to the raw water pump.

jsonova99
06-19-2011, 10:49 PM
check your trans oil cooler....it might be clogged with pieces of your old impeller
Remove the hoses off each end of the cooler and with a garden hose spray water in the opposite direction of normal flow to backwash the cooler.

BTW, I'm not a big fan of the fake-a-lake (especially when they move out of place like yours did) I use a 5 gal bucket with a hose connected to the raw water pump.

That's a great idea, I'll probably try that next time

mtajpa
06-19-2011, 11:00 PM
Did you check the raw water pump seal it may have been destroyed and you are sucking air through it.

gotta_ski
06-20-2011, 05:30 AM
How do you know you're not getting any suction? Are you now using the bucket method?

The boats I've seen (including mine) have the trans cooler upstream of the impeller, so the shredded impeller pieces couldn't be clogging that. They could be in the other cooler lines. I've found them under the water distribution manifold above the thermostat before too.

Dave is right that if your trans cooler is blocked it could impede the suction. Give it a visual, or flush it like he said, then check your other lines. When the impellers come apart on me I try and match up the pieces as best I can so I know if I've found it all or not, or at least most of it.

Also, if the cover plate over the impeller doesn't have a good seal it will leak air in and reduce the suction.

jsonova99
06-20-2011, 08:14 AM
How do you know you're not getting any suction? Are you now using the bucket method?

the raw water pump is bone dry as are the lines coming into it. When I fire up the engine, the water from the fake a lake is usually sucked right up which is visually obvious, plus after a few seconds it will start coming out of the exhaust. I opened the freeze plugs up and nothing drained out at all either. There's no water getting into the pump. I would also think that anything after the pump is okay because there's been no water to carry pieces of impellar any further.

Regarding the bad seals, I had a raw water pump go bad on me before and it still sucked up water, just shot it out at high pressure through the rear bearing. The front seal has a fresh gasket (not the one that heated up). I'm going to take a look this afternoon for more signs of blockage and try starting it up again.

oldairboater
06-20-2011, 08:14 AM
Need a seal to pull suction and like stated above find the impeller pieces. Fake a lake looks like a good way to burn a block-----up.

Worthing skier
06-20-2011, 09:55 AM
Hi there

Is the impeller turning correctly ?.
The reason I ask this is I had the mainshaft of the pump to the flange on the front of the crank spin.
Hence the pump was not being driven ,ended up removing the pump and re-bushed the flange to get a good interference fit .

This can be caused by poor alignment of the pump to the suporting bracket

Hope this may help


rgds


Kevin

east tx skier
06-20-2011, 11:56 AM
Do you have a raw water strainer installed on your boat? If so, make sure it is sealed properly. They are a common source of this problem on boats that have them.

jay
06-20-2011, 12:19 PM
I realize this post offers little reconciliation to the current situation and possible "sinking" feeling you get when your boat is not cooperating, but maybe try installing the Flush-Pro after you get this thing worked out? For only $20 more than fake-a-lake...I have never had an issue with this system, granted I have only used it 5-6 times, but installation was easy, it worked from day 1, and it did not introduce new issues.

http://www.skidim.com/prodinfo.asp?number=DP7

This IS the best $60 you will spend IMHO.

jsonova99
06-20-2011, 05:47 PM
there's no suction, I started the motor up and put my hand on the one side of the pump (probably not a smart idea, but desperate times call for desperate measures), impellar is spinning. What I did notice is that there is an o-ring riding on the outer shaft. I'm guessing that when things heated up it might have popped out and that's why I have no suction? I'm not sure if I can work that o-ring back into place or not or if I have to replace the pump. On hold with skidim as I write this.

EricB
06-20-2011, 06:52 PM
I would also suspect drawing air from the shaft seal. Air is less dense and easier to pass than water, and thus may not draw liquid.
I had to replace my RWP due to a situation very similar to what you are experiencing. Place some wheel bearing grease or liquid soap on the shaft seal area and see if some suction develops. Or, remove pump and block ports and and lightly pressurize. Submerge or use soap and look for bubbles at the seal area.

Cloaked
06-20-2011, 08:50 PM
What brand pump and what engine?

Sherwood on a 351, by chance?

jsonova99
06-20-2011, 09:35 PM
Talked to Richard at Skidim, he thinks I fried the shaft seal seal (the o-ring is the dislodged overheated seal). He thought I could install a new one, but I think I'm just going to buck up and buy a new one and make sure this doesn't happen again. Time to get the boat on the water, I don't want to spend another weekend in the driveway wrenching on it.

Thanks for all the input. Hopefully this is the only issue that surfaces.

jsonova99
06-21-2011, 08:49 PM
I'm curious if I should be concerned about the engine water pump at all? I assume if that goes bad I can just pick one up at an Autozone for a 351 Ford engine, wouldn't think that it would be any different between car and boat.

oldairboater
06-22-2011, 03:11 AM
Too easy for me to order from skidim. Could be the same pump, but I don't know. I have other things to do besides worry over a water pump. I am a fanatic about keeping my engines cool and oiled. I will not skimp, doubt, or risk an engine over parts.I'm curious if I should be concerned about the engine water pump at all? I assume if that goes bad I can just pick one up at an Autozone for a 351 Ford engine, wouldn't think that it would be any different between car and boat.

Table Rocker
06-22-2011, 07:27 AM
I'm curious if I should be concerned about the engine water pump at all? I assume if that goes bad I can just pick one up at an Autozone for a 351 Ford engine, wouldn't think that it would be any different between car and boat.I wouldn't be concerned about the engine water recirculating pump at all. It doesn't have rubber seals or a rubber impeller, so you should be fine.

PolarBear
06-22-2011, 10:50 PM
Another thought, did you put the new impeller in with the fin rotating the proper way? If you put them in opposite I'm not sure if they will flip over and go the right way. Total guess, haven't tested it or know the answer. I always start back at the beginning if something doesn't work if I take it apart and not assume anything.

Thrall
06-23-2011, 05:54 PM
Fins will flip to the right direction on the first rotation of the pump, no worries there.
Probably blown seal = no suction.

1redTA
06-23-2011, 06:27 PM
it is possible to install the raw water pump "up side down" any chance that may have happened?

jsonova99
06-23-2011, 07:49 PM
Just got the new pump and fresh hoses, hope this is it. I'll post my results when everything is installed and tested. Thanks again for all of the help.

Cloaked
06-24-2011, 08:01 PM
Just got the new pump and fresh hoses, hope this is it. I'll post my results when everything is installed and tested. Thanks again for all of the help.Some particular pumps have a certain direction to be installed and can easily be mistaken in direction.

jsonova99
06-25-2011, 09:34 AM
New pump worked fine, inspection of the old one shows no signs of why it should have had a problem. I'm going to replace the seal in it and keep it as a spare. I think I had a leak in one of the old hose joints down by tranny cooler. New hoses and new pump work fine. Very likely that the old pump was fine even after the overheat, but the hose leak was causing the lack of suction. Only ran the new one with the fresh hoses installed. Anyway, we're back in business.

As far as install goes, these particular Johnson pumps are pretty much idiot proof, they only fit one way which is always a good design feature.

JJMorris3
06-25-2011, 10:24 AM
Glad to hear you are fixed up. Nice work! Just a heads up regarding the idiot proof comment: this idiot sheered one of the copper cover plate bolts by over tightening during impeller replacement this winter on my Johnson pump. Luckily I was able to back it out with a small drill bit. But it got my blood pumping... I think I actually remember saying to myself "What an F-ing idiot" :)

woobiedmd
06-25-2011, 10:31 AM
If you were able to fix your mistake- you're not an "idiot". And if you did fix it and not tell anyone, did it really happen?

jsonova99
06-25-2011, 02:20 PM
I have plenty of those stories I was strictly talking about the orientation of it.