Warm water in bilge, 4.3 mercruiser???

[Whitey72]

Hello all again from Australia,
Once again I am seeking knowledge from more learned persons than myself. I have a 2006 tahoe q4 ski fish with a standard 4.3l mercruiser carby with alpha 1 gen 2. Sorry I don't have the actual serial numbers as the easy access sticker has gone blank and I don't know where to look to find them.

My problem only started today when I was out fishing with mates. My boat is mostly used in salt water but always flushed at home everytime. Today at the boat ramp after loading back on the trailer I then pulled the bung and then was shocked to see a constant strong flow of very warm water for the next 5 mins. My whole bilge must have been full without my knowledge. While fishing I saw that the motor was performing great as usual and running at normal temp as I'm paranoid re overheating the motor. When I got home and flushed the motor I looked carefully and saw there was still water coming from the exhausts next to the leg mounts (sorry I don't know their proper name) but now also a constant stream out of the open bung hole. Both were warm from the engine. The motor did not run any hotter, again and I checked all hoses I could reach and all looked new and plyable (not old and stiff). I felt where the hoses come out of the heads and no leaks there, up to the thermostat housing and then out to exhaust elbows and no leaks. I'm guessing somewhere after there and before the transom is a leak that I can't see emptying into the bilge.

I want to know what next as I'm now shore bound as I don't want to risk anything more serious until I sort it out. My guess is all plumbing etc is original from 2006 and probably is due to be replaced anyway but don't know where to start. I'm also guessing its easier to remove the whole motor to do this and check other things while I'm at it?

Any help is greatly appreciated as I'm now search for service manuals.
Cheers Whitey

 

[achris]

Re: Warm water in bilge, 4.3 mercruiser???

Sounds like you might have a broken hose clamp somewhere. I had the same problem and couple of years ago, but it was on the cool-fuel system, which you don't have. What you can do is pull the drive and put a hose in the open water intake hole in the bell-housing and start looking for leaks in the engine room.

A few good places to start are the hose from the transom plate to the single point drain manifold, the exhaust elbow hose clamps are notorious failures too...

Chris...

 

[tpenfield]

Re: Warm water in bilge, 4.3 mercruiser???

Maybe the best thing would be to put the boat back in the water and check for leaks in the bilge and all the hoses, etc. If there isn't any start the engine while in the water and check again. Lots of things that it could be so best to have a look.

 

[Grub54891]

Re: Warm water in bilge, 4.3 mercruiser???

You said all plumbing is original,does it have a water heater? Could have blew a hose on that,if it gets water from the engine they fillup fast! Some have the heaters in a closet,some in the engine room. Did you look at the motor when running?
Grub

 

[ktbarrentine]

Re: Warm water in bilge, 4.3 mercruiser???

As Chris said....exhaust elbow hose clamps are a good, easy place to start looking. Mine were loose about a year ago (twenty years old and I dont think they had been touched). Same exact symptoms/results. Tightened them up, problem gone. Best of luck.

 

[Whitey72]

Re: Warm water in bilge, 4.3 mercruiser???

Thankyou all for the replies. Last time I had her out before today was only a month ago and for the last 18 months since I bought her till then she has been a very dry boat. During that 4 day trip a month ago I did smack her through some very choppy seas which let the kidneys know they were still there, so that might have loosened something.

I have been searching for some manuals and they are definately hard to find. As I said I don't know the serials for the motor and I'll have a good look tomorrow, can anybody tell me where to look? As I said it's a 2006 make tahoe 4.3 with carby. I have found #25 but can only get sections 1-3 working. Another thread said manual #37 is the cooling system which is what I'd like to see but can't find any copies of that one. I'd just like to see some pictures of what's behind the motor as I can't see a thing and sorry I'm not sure of the points all of you have been identifying as this is the first stern drive I've had.
Cheers Whitey

 

[Bt Doctur]

Re: Warm water in bilge, 4.3 mercruiser???

Boatinfo - The library, containing manuals, brochures and other technical documents from the last hundred years! takes a while to load but does work.

 

[achris]

Re: Warm water in bilge, 4.3 mercruiser???

DRIVE MANUAL
ENGINE MANUAL
TKS MANUAL

Download and save... Then make a backup...

Chris........

 

[Whitey72]

Re: Warm water in bilge, 4.3 mercruiser???

Thanks all for your replies. I had another good look over her last night and nipped up all the hose clamps I could find. All were good as well as the hoses that I could see. I did find the engine number plate which is 0w374008 for any reference. As its very cramped there restricting a good look so I have bought an inspection camera and just waiting for delivery. Once arrived I'll drag her out and start her up and hopefully see the water leak.
Chris, can you please tell me where the "hose from the transom plate to the single point drain manifold" is? I can't seem to find it in the manuals either, must Have had a man look.
Cheers Whitey

 

[achris]

Re: Warm water in bilge, 4.3 mercruiser???

Look in the engine manual in section 6B, page 7. That is the flow diagram. Item 'e' is the single point drain manifold (they are calling it a 'Water Distribution Housing') There will be a hose from the transom to the power steering oil cooler (h), then the check valve (g), then a hose from that item 'e'. As your engine is not MPI you don't have item 'f', a high pressure fuel pump.

Chris..........

 

[achris]

Re: Warm water in bilge, 4.3 mercruiser???

Look in the engine manual in section 6B, page 7. That is the flow diagram. Item 'e' is the single point drain manifold (they are calling it a 'Water Distribution Housing') There will be a hose from the transom to the power steering oil cooler (h), then the check valve (g), then a hose from that item 'e'. As your engine is not MPI you don't have item 'f', a high pressure fuel pump.

Chris..........

 

[Whitey72]

Re: Warm water in bilge, 4.3 mercruiser???

Hello again Gents,
Well I finally got a day off when it wasn't raining and dragged the boat out, started her and had a good look with my new inspection camera. I found the leak and have attached a few photos. Sorry for my ignorance but I have no idea what they are called. There are two that I found with the port side leaking with a constant stream when the motor is running, but there are drips coming from the starboard side as well so it's probably not that far away either. They are under the heads screwed into the block and look like a sender mount but no wires are going to them. I also found the remains of a blue plastic tap and wonder if they have broken off hence the leak. Hopefully it looks like an easy fix and if anybody can tell me their real name so I can buy and replace would be great. Any tips for removal and replacing would also be great. I checked all other pipes / hoses and all look great. Fingers crossed!!
Cheers
Whitey

 

[Whitey72]

Re: Warm water in bilge, 4.3 mercruiser???

Well after a bit of research on the net I have worked out that they are the block drain plugs for winterising, not that we need to do that down here. The broken plastic handle fits perfectly with the port side thread left in the metal mount. At least I can confirm where they come from. Can't say I'm impressed with plastic screw in plugs and now trying to source some new ones. Thanks for all your help.
Cheers Whitey

 

[achris]

Re: Warm water in bilge, 4.3 mercruiser???

22-806608a1

 

[MarkSee]

Re: Warm water in bilge, 4.3 mercruiser???

... plastic screw in plugs and now trying to source some new ones. Thanks for all your help.

West Marine sells them; even had a choice between OEM and Sierra at 1/2 the cost.
I bought some extras for my boat.

Mark

 

[achris]

Re: Warm water in bilge, 4.3 mercruiser???

West Marine sells them; even had a choice between OEM and Sierra at 1/2 the cost.
I bought some extras for my boat.

Mark

We don't have West Marine in Australia. His only option is OEM from a Merc dealer, hence I posted the part number.