Logo
FULL SITE MENU

Volvo Penta not pumping water

J

johnsonv4

Member
Hello,

Our stern drive is not taking in water with muffs or in tub. When we attach garden hose to intake pipe to salt water pump entire system going forward is working correctly.

Any thoughts? We ran the water hose in opposite direction and water came out water intake on lower unit to rule out obstruction.

Thanks
__________________
1993 Larson All American 17 Bowrider, Volvo Penta 230B w/Volvo SP CD Trim Stern Drive, and Load Rite Trailer.
 
Impeller should be checked.

Should be a flat plate on front of pump attached with tiny screws.....

Use two flat bladed screwdrivers to gently pry out impeller.

john
 
Today We checked the new impeller we installed the other day. Is it possible the boat needs to be in the water so that the water line is at almost the same height as the salt water pump.

Also, should we plug the bottom hole behind the prop while using the muffs.

Lastly, what is a safe operating temp we should be looking for?
 
We just disconnected the intake hose from the fitting on the outdrive and flushed a garden hose in to the fitting and water came out of the lower unit intakes without any obstruction. We also attached the hose from the boat side of the intake hose and water flowed freely to the other end which is still disconnected from the outdrive fitting.

We have not taken the boat out as of yet. Does the outdrive need to be totally submerged for this to work? We tried muffs secured with a bungee cord and placing the outdrive in a tub with water 2-3 inches above the water intake.
__________________
1993 Larson All American 17 Bowrider, Volvo Penta 230B w/Volvo SP CD Trim Stern Drive, and Load Rite Trailer.
 
We bought the boat used a couple of months ago and just got the motor running the other day.

We were told the boat ran last year and that the previous owner reported that there were some problems with the heat exchanger.

We cleaned it, took it apart and flushed the core, replaced all the seals and do not see any leaks.

We inspected the salt water pump impeller yesterday which we installed new a couple of days ago and it looks good.
__________________
1993 Larson All American 17 Bowrider, Volvo Penta 230B w/Volvo SP CD Trim Stern Drive, and Load Rite Trailer.
 
johnsonv4 said:
Today We checked the new impeller we installed the other day. Is it possible the boat needs to be in the water so that the water line is at almost the same height as the salt water pump.

Also, should we plug the bottom hole behind the prop while using the muffs.

Lastly, what is a safe operating temp we should be looking for?
Click to expand...
Remember that this particular sea water pump is Engine Mounted. This means that it PULLS water up and through the drive.

The Volvo Penta 230B w/Volvo SP CD Trim Stern Drive is one of the last of the AQ series drives.
This system uses a Water Neck fitting that will be on top of the suspension fork.
These are a "wear item" and must be routinely replaced.
They corrode under the S hose where you cannot see.
They will leak air, and ANY amount of air in ANY portion of the suction side will cause pump failure.
Trust me on this!

No, the drive should not require being in the water in order for the sea water pump to work.
If it is not working while on the muffs (and yes, plug the drain hole) then you have an issue.

As for engine temperature, see your OEM manual. Don't have one??? Then it would behoove you to purchase one, IMO.
This will use a closed system, so your temp will be warmer than if raw water cooled!
I believe that the OEM calls for 82* or 83* C..... so that converts to approx 180* F.
Varify this with your OEM manual!

Also look closely at the inside of the sea water pump cavity.
Any excessive wear at the two thrust surfaces, and/or impeller cam, will cause this pump to not work well.
Likewise with any other suction line connections that may be breaching a good suction seal.
All it takes is a tiny tiny bit of air to cause loss of water suction.
Physics!

Hang in there.... you'll get it!
 
Last edited:
Ran it this morning for 30 mins. At 1500-2000 rpm with a garden hose on the cooling hose on the outdrive.

Engine ran fine and temp did not go over 195f.....

This weekend we really need to drop it in the local lake to give it an easy run.

Is okay to run it at 195f?
__________________
1993 Larson All American 17 Bowrider, Volvo Penta 230B w/Volvo SP CD Trim Stern Drive, and Load Rite Trailer.
 
Rick,

Thanks for your informative response.

When we pulled the hose of the fitting it appeared okay but it did have a salt build up around the neck where the hose was attached.

Is it difficult to change out the fitting? It looks tight in there. Is it possible to pressure test this system for leaks?
 
First.... be careful that you don't give yourself a false positive while on the garden hose!
If you have enough water pressure, and water volume, a suction leak here may not be noticed.

As for changing this fitting, you may want to kill several birds with one stone here!
Have any of these items been recently replaced?

Drive bellows
U-joint bearing crosses
Water Neck fitting
Shift cable

If not, all of these are much more easily accessible with the transmission ONLY out of your way!
Several birds/one stone!

Use a bit of heat at the area of the threads before you attempt to remove any fasteners.

BTW, I did an edit to post #6 re; thermostat temp.

.
 
Last edited:
I don't know what "easy run" means to you, but keep in mind that this water neck fitting is submerged at low speeds.
A fauly or corroded fitting may not pose an issue at these lower speeds.

However, as you come up onto step, this part comes up and out of the water. That is when an issue can occur.

See post # 6 for an approximate operating temp..... then see your OEM manual.
Ya can't go wrong when using the OEM manual.
 
Thanks again Rick.

So, having a temp of 195f on a garden hose in the driveway is s little high. We replaced the thermostat, all seals and O rings to and from the heat exchanger and cleaned and flushed out the heT exchanger. Is there a reason why we are running a little hot?
 
It is not uncommon that an engine will run slightly higher than the stat's rating.
I'd check your instrument against a lasor temp sensor reading.
Your actual temp may not be that high..... but if it is, you will want to find out why.
 
Get a short piece of 1" rubber/ vinyl hose and put on suction side of pump.

Put 1" hose in bucket, fill with water from garden hose and run engine that way.

At idle, garden hose should keep up at partial flow.

at 2000 rpms or so, garden hose (at full flow) WON"T keep up and you'll have to idle for a bit.

This way you'll see if pump is working.

Maybe the hose at transom is collapsed? Internal hose separation?
 
I believe sometimes the tube thru the intermediate housing of the outdrive (not the bottom part where the prop attaches, nor the top part where the shifter linkage is located) can have a bad seal. It is underwater at low speed and maybe when on plane but will suck air in the driveway. Looking at the video it seems that you have a lot of exhaust coming out possibly thru a tear in the exhaust bellows. I would suggest you closely examine the exhaust bellows which is difficult when it is attached. It's not a huge job to remove the upper gear head and inspect/replace both bellows, the u-joints and the raw water intake hose and fitting.

I'm a firm believer in preventative maintenance as I've learned the hard way. The pumps have been very reliable for me over the years, but they are easy to rebuild.

Good Luck!
 
I watched your video and I have to put my 2 cents in. I have twin volvo pentas (AQ171C's) and the setup is very similar, While on land I had to hold pressure on the muffs and cover the drain underneath to get the water to the raw water pump before she started pumping good. Another thing that I did was to pack the impellar with vaseline to make it prime. I think the cavity in the leg holds a lot of water just going on how much water drained out when I shut them down, but that's just me from experience. Also last year it started running hotter towards the end which I attribute to barnicles growing in the lines (I had bad filter screens as well). This year the engines ran very well around 175-180 and still in the water. Hope this helps you.
 
Installed a new rear seal and gasket on the water pump as we did notice a small leak at the back end of the raw water pump.

Attached the muffs with the same results as before.
 
I keep thinking about this... Make sure you are letting the leg fill with water, squeeze the muffs and plug the hole on bottom as well. The water has to go somewhere at that point, when water comes out exhaust, let go (engine running of course).
 
braxton419 said:
...... which I attribute to barnicles growing in the lines (I had bad filter screens as well).
Click to expand...
Good point re; the barnicles. I've pulled a hand full of those little guys from lower units before...... however, this has been from drives/boats that have been moored..... usually not found on smaller trailered boats.


Johnsonv4, I'm not much in favor of circumventing portions of the suction system for testing.... not unless this is part of our P of E (process of elimination).... in which case, I'm OK with this!
IMO, best to test the system as it is, and trouble-shoot from there..... P of E is the best method.... one item at a time!

Now, that being said, I did mention the water neck fitting to you, and you did confirm that it appears to be OK.
Note that there is a special "beaded" gasket directly underneath this fitting.
The gasket will dry up over the years, and may loose its seal against the very top of the pivot tube. (This is an absolutely necessary seal!)
This may create a breach in the suction seal that is impossible to detect without disassembly.

There is no reason that running on the muffs will not work, "IF" all is as it should be, and with the lower unit drain hole plugged.
If it will not work, then you have a suction breach somewhere, or a sea water pump that is not working correctly (assuming that all else is OK).

.
 
Thanks. Will try it again before taking the boat out.

Tried three different pair of muffs with clamps, tape, etc... The placement of the water intakes on the lower unit are in worst possible location for muffs.
 
johnsonv4 said:
Tried three different pair of muffs with clamps, tape, etc... The placement of the water intakes on the lower unit are in worst possible location for muffs.
Click to expand...
You should not need tape, and you may not be using the correct muffs.

I'm trying my best to explain to you that if your system is working correctly, it will pull water up and through the drive and onto the engine.

If it will NOT, then YOUR system is NOT working correctly. I don't know, because I'm not there!
These are all just suggestions ONLY!


Let's for the minute look at this from another angle. (some humor and constructive sarcasm here :) )

I could remove your water neck "beaded" gasket, and re-install the water neck....., I could remove the lower pivot tube O-ring...., I could loosen a few suction hose clamps a little bit........, and yet with enough duct tape on the muffs, and enough water pressure and volume, I could give your sea water pump a supply of cooling water.

Wouldn't you rather know that it is capable of doing this on it's own?

This is why I suggest that circumventing portions the system may give your a false-positive.

Hey, I'm in your corner and want to help you! :)
 
Last edited:
Thanks Rick.

Yes I noticed the gasket when attached the hose and it's something we should change out along with a new fitting.

On another note, I did notice the temp rising when we were getting plenty of water. The temp was in the 195-205 range. We flushed the heat exchanger and replaced all the seals and O rings. Question: is it possible the internal water pump could be failing? I understand it's driven by the WP/Alternator belt, but could the WP develop internal problems that would cause it to fail or not perform correctly?
 
That pump would be your Engine Circulating pump..... (aka "Circ" pump)...... ! Doubtful that it is bad.
Although, never say never!

Keep in mind that all of the cooling water that we can supply to a cooling system, must also have a non-restrictive means of exit!
I.E., Exhaust man, or any other part that may restrict flow.
 
Thanks.

One of the rubber exhaust hoses is torn (port). But the exhaust appears to be flowing out of these hoses as well as the exhaust port above the prop.

About to take it out to the lake for a test. Will update in a few hours.

Thanks again for all your help.
 
Well took it out today and it went okay. We ran it for an hour or so and the motor ran good and string.

Rick, I do believe you mentioned that it would pump water well at low speeds and it did. When we pushed it a few times after confining that things were going well and the temp remained below 200*f. We opened it up twice and hit 40 mph and noticed the temp climb to 205*f so we cut back to 15-20 mph and temp stayed steady at 195-198*f.

So, looks like we will need to change out the hose fitting and gasket on the out drive.

Question: reading the OEM manual, I noticed that the thermostat does not fully open until 198*f. Now that's the temp that we were getting most of today. So, am I assuming that this is our normal operating temp?

Thanks
 
Took the boat out again today for a few hours. Again with the same results with the temp staying around 195-200*f and climbs a little when we push it, then we back off and the temp levels off again at 195-200*f.

Thanks
 
We took the boat out for a good 4-5 hour run. Made it down the Charles River to the Boston Harbor with no problems. Again the temp is staying constant at 195-200*f from 5-40mph....

So, looks like this is our operating temp. We will remove the outdrive for the winter and do some maintenance work including replacing a torn exhaust hose, raw water fitting, etc....

Question: any curve balls to be concerned about when removing the outdrive?

Thanks
 
Back
Top