Is it my water pump?-gctid374406

[Guest]

Hello everyone,

I purchased a '90 2755 bayliner (w/ 454 & bravo 2) a few months ago and this past weekend i finally got the motor to fire up.

In the process I had no muffs, we cranked it a few times but the batteries were dead. Finally cranked it using a good car battery and it fired up, I let it run for 30-40 seconds just to make sure it didn't die again then turned it off.

Went and got the muffs and hooked them up to the bravo 2, fired the motor and let it run for 5 min or so.

Kept looking at the temp gauge but no movement at all. Went down the leader so I could peak at the out-drive...realized the water from the muffs was no being sucked in at all.

I immediately turned the motor off. Checked temp on motor by hand...one side was hot other side cold. Removed a water line from the motor and all I got was a bit of anti-freeze out.....The water from the muffs didn't go through the engine at all. Which makes me wonder the reason why the temp gauge didn't move could be due to barely any liquid being in the motor...or maybe the gauge doesn't work - Who knows at this point.

So no water = WATER PUMP you might say?

How can it be? I have a receipt from April 2011 where the bellows, gimbal bearing, exhaust hose, 4' blower and "RAW water pump (As stated on the receipt) were replaced from a local shop. Boat was pulled out of water Oct 30,2011.

Did I burn the pump running it without water the first 30-40 seconds?

What's the easiest way to check if my pump is indeed the problem? Is there a waterline going from the outdrive to the rear of the motor I can remove and see if water is being pumped through?

[2850Bounty]

NoLeafClover wrote:


1.... In the process I had no muffs, we cranked it a few times but the batteries were dead. Finally cranked it using a good car battery and it fired up, I let it run for 30-40 seconds just to make sure it didn't die again then turned it off.

Went and got the muffs and hooked them up to the bravo 2, fired the motor and let it run for 5 min or so.

Kept looking at the temp gauge but no movement at all. Went down the leader so I could peak at the out-drive...realized the water from the muffs was no being sucked in at all.

I immediately turned the motor off. Checked temp on motor by hand...one side was hot other side cold. Removed a water line from the motor and all I got was a bit of anti-freeze out.....The water from the muffs didn't go through the engine at all. Which makes me wonder the reason why the temp gauge didn't move could be due to barely any liquid being in the motor...or maybe the gauge doesn't work - Who knows at this point.

So no water = WATER PUMP you might say?

How can it be? I have a receipt from April 2011 where the bellows, gimbal bearing, exhaust hose, 4' blower and "RAW water pump (As stated on the receipt) were replaced from a local shop. Boat was pulled out of water Oct 30,2011.

2.... Did I burn the pump running it without water the first 30-40 seconds?

3... What's the easiest way to check if my pump is indeed the problem? Is there a waterline going from the outdrive to the rear of the motor I can remove and see if water is being pumped through?

1... I don't need to explain to you what happened.

However, you may want to know what occurs to the rubber exhaust components when run dry for this duration.

I'd advise that that you remove your exhaust risers and examine these before you even think about taking the boat out..... even after reparing the Sea Water pump.

2... I'd be willing to bet that you did!

We can ruin an impeller in as little as 8 to 10 seconds if run dry.

3... Remove it, and disassemble it.

Get yourself an OEM service manual for your specific engine model.

Look at the cooling system via your engine serial number.

Follow the sea water path from the drive to the engine, and then onto the exhaust system and out the drive.

This will help you understand your cooling system.

.

[Guest]

^^^^What he said.

The raw water pump should be on the starboard side of the engine down low- it's belt driven, and fairly easy to get to.

[Guest]

dont ever run your boat without water. Thats bad mk. 30-40 seconds was WAY too long.

[Go Aweigh2452]

You did not necessarily ruin your impeller the first time you ran the engine for those 30-40 seconds. I did an experiment a few years ago and knowing I was about to replace my impeller, I ran the engine exactly 60 seconds with no water. I pulled the two year old impeller and it was fine.

However, you need to know running the engine while on muffs can be a concern depending on your home water pressure. Too much pressure will not allow water to run through the impeller. It is probably toasted now. Always check to ensure a low flow of water is entering the muffs and watch for the leg of the outdrive to see water coming out. Without the check, you can damage the impeller. Since the engine was not too hot on one side, I doubt you lunched anything other than the impeller and or housing.

I also recommend the other checks Rick and others have stated...

FWIW, I have seen many outboard motors started prior to them going into the water on the launch ramp. I am always amazed at this and I was told they do it all the time... It takes them maybe 3-5 mins before that engine is dunked far enough to start "peeing" but I have seen it with my own eyes...

[2850Bounty]

Doug, while the block and the one manifold may not have gotten too hot, I can almost guarantee that his rubber exhaust couplers are now blistered on the interior.

I hope not, but I'm doubtful that they would have survived that much heat.

And you may be correct... if there was enough residual water within the pump, it may have lubricated the impeller for a 30-40 second run.... but 4-5 minutes???? I doubt that it survived.

Outboards... another story!

Many of these outboard impellers have long fingers/blades, and some can take dry starts better than others.

I too see these outboard owners fire their engines up before hitting the water.

Dumb thing to do at best! :thumb

If for no other reason than that cold water is now rushing around potentially hot engine components. :thumb

.

[Guest]

Two years ago the muffs fell off my 7.4 B2. 20 seconds later , I was buying my second impeller and housing in a week.

[Guest]

2850Bounty wrote:
1... I don't need to explain to you what happened.

However, you may want to know what occurs to the rubber exhaust components when run dry for this duration.

I'd advise that that you remove your exhaust risers and examine these before you even think about taking the boat out..... even after reparing the Sea Water pump.

2... I'd be willing to bet that you did!

We can ruin an impeller in as little as 8 to 10 seconds if run dry.

3... Remove it, and disassemble it.

Get yourself an OEM service manual for your specific engine model.

Look at the cooling system via your engine serial number.

Follow the sea water path from the drive to the engine, and then onto the exhaust system and out the drive.

This will help you understand your cooling system.

.

Thank you Bounty...I Will do just that right after I get to see the conditions of the w.p

Hopefully it's just the pump.

I don't know what told me 'was okay' to run the thing for a few seconds dry like on some jetskis :noob-

[Guest]

I always use a livestock trough to do my run testing. Our water pressure isn't that great and since I do my work alone the muffs can leak, fall off, or my wife or daughter will come out unaware and turn the hose off, and it might be a minute or two before I notice.

The large rubbermaid trough solves that problem and also makes it obvious if you are developing a vacuum leak. It's as close as you can get to simulating the boat being in the water because it still has to suck up the raw water where muffs can force it into the drive.

If it was sitting awhile and then started dry, impellor is probably gone, and 5 minutes likely blistered the ruber exh couplers. You can fill the boat up with water real quick if one of these fails while running!

[Guest]

rkcarguy wrote:
I always use a livestock trough to do my run testing. Our water pressure isn't that great and since I do my work alone the muffs can leak, fall off, or my wife or daughter will come out unaware and turn the hose off, and it might be a minute or two before I notice.

The large rubbermaid trough solves that problem and also makes it obvious if you are developing a vacuum leak. It's as close as you can get to simulating the boat being in the water because it still has to suck up the raw water where muffs can force it into the drive.

If it was sitting awhile and then started dry, impellor is probably gone, and 5 minutes likely blistered the ruber exh couplers. You can fill the boat up with water real quick if one of these fails while running!

Okay now I'm getting worried...I am not familiar with the terminology so pardon my ignorance but what do you guys refer to as couplers? The rubber tubing that comes from the two exhaust manifolds?

Risers I take it are the manifold extensions ?

Thanks for the help so far everyone.

Looks like it's going to be a very busy weekend.

[2850Bounty]

NoLeafClover wrote:
Okay now I'm getting worried...I am not familiar with the terminology so pardon my ignorance but what do you guys refer to as couplers? The rubber tubing that comes from the two exhaust manifolds?

Risers I take it are the manifold extensions ?

Yes, the rubber couplers (#1) are what I mentioned earlier. These join the exhaust risers to the exhaust Y-pipe (#6).

They are intended to be wet during engine operation, and if not wet, can over-heat and blister.

You will also have exhaust back flow prevention flappers (#7) within the system. These too may be blistered.

Yes... the risers are the upper half or upper portion of the cast iron exhaust components.

These will separate from the manifolds.

This will be similar to your exhaust system.

[Guest]

Just wanted to give an updated.

Here is what my dad found.

http://www.youtube.com/watch?v=hMEI4GMSjnU

If you have a 454 on that small engine bay it will be a nightmare to pull out.

1st- The muffs i used were too small for the bravo 2.

I used the universal muffs they sell at west marine.

I had to flip them vertically so that it would cover all the intake holes on the Outdrive.

2- I checked the risers and gasket as well as the rubber exhaust tubes and there were no cracks of any kind.

Thank you everyone for your help,

-Cheers, Ari