Overheating engine and leaking pedestal

[Bing]

Has anybody else had a problem with their Volvo saildrive overheating? Ours is a D1-20 in a Bavaria 31 Cruiser. It's an intermittent problem that no-one has been able to solve. The mechanic says it's operating within Volvo guidelines, yet we get an overheating alarm - not every time, but intermittently. We've installed blowers in and out of the engine compartment and that seemed to work for a while during winter. Now our weather is warming up and the sea temp is rising...and it's happening again.
The next problem we have is a severe leak coming through the steering wheel/autopilot/instrument area on the pedestal in the cockpit, straight through into the back cabin...only in heavy rain. Anybody, anybody????

 

[Pamsboat]

Our 1985 Bavaria 960 has its original Volvo engine. We have had problems with the engine overheating. There are 3 replacements we made:

Replaced impeller (part of water pump) Replaced raw water strainer Replaced hoses in the engine cooling system.

Marine growth in New England is especially a problem. I have to be conscious of blockage in the area of the water intake which is in the mid to upper section of the outside of the sail drive housing. In our location even muscles attach themselves.

Hope my reply is helpful

 

[Pamsboat]

Leaking Pedestal

When I purchased my boat I knew there were water problems, but mostly rain water. I looked for areas where the the seals had deteriorated. I tried to correct the area around the pedestal, the compass, the wires and other places that water could come in by applying a caulking compound such as Boat Life. Where ever possible I lifted up items like the compass, cleaned off the old sealant and re-bed the compass& rim to the pedestal. Always make sure make sure nuts, bolts, screws have a caulking compound to. to seal out water.

 

[duncanhoo]

are you getting any steam in the exhaust after running for a while? This would look like fine white smoke that quickly evaporates/dissipates?

Has anybody else had a problem with their Volvo saildrive overheating? Ours is a D1-20 in a Bavaria 31 Cruiser. It's an intermittent problem that no-one has been able to solve. The mechanic says it's operating within Volvo guidelines, yet we get an overheating alarm - not every time, but intermittently. We've installed blowers in and out of the engine compartment and that seemed to work for a while during winter. Now our weather is warming up and the sea temp is rising...and it's happening again.
The next problem we have is a severe leak coming through the steering wheel/autopilot/instrument area on the pedestal in the cockpit, straight through into the back cabin...only in heavy rain. Anybody, anybody????

 

[duncanhoo]

We are tracking down a similar issue on our volvo and i believe it is blockage somwhere in the system restricting the waterflow ever so sllightly. We have a mechanic looking into replacing the exhaust elbow or next opening the heat exchanger and looking for brokend bits of impellers or other items.

 

[firehoser75]

Water Blockage?

Have you ever "backflushed" the saildrive leg? If not, that should help remove some of the growth inside the leg water intake. For detailed instructions on how to do this, go to the Bavaria Yacht Owners website at byoa.org. Look under "upgrades and mods" then under "Alibi".
Other places to consider or check include the inbound end of the heat exchanger where you might find a partial blockage caused by anything from sea life to impeller parts, and the exhaust elbow. The elbow will only last a few years and then they corrode inside to the point where they are ineffective. Also make sure your seawater strainer is clean.

Hope this helps,
Tom

 

[b31]

Overheating d1-20

I have a 2007 Bavaria 31 also with the D1-20, and I do get this overheating alarm every now and again, and in actual fact the engine does overheat as engine coolant overflows from the tank. This is happening also on another two identical Bavaria 31 boats of the same age.

But we all noticed that this happens only when you are motor sailing, i.e. the boat is heeled and the engine running, if you straighten up the boat the engine cools down and remains in normal operating temp.

Someone told me that volvo have issued a fix for this (apparently by lifting up the position of the coolant reservoir, which currently sits at the same height as the heat exchanger) but I've been trying to look this up with no results yet. I plan to try it in any case as it sort of makes sense, and will post the results

 

[Gnomeface]

I've had engine overheating once on my 2007 Bavaria 31 and tracked down the main problem. It was a misaligned water intake filter, resulting from (in my view) a bad design plus my own mistake after a routine check.

To check the filter it is necessary to remove the cap, then the round sealing plate (which on mine needs a pair of pliers to get enough grip to remove it) before the filter can be pulled out to remove odd barnacles, etc. If the filter is not positioned perfectly when replaced (and it's at the very back of the engine compartment) then although it seems correctly fitted, and the sealing plate can be refitted and the cap replaced, the unit does not seal properly - and the circulation pump now cannot suck fresh seawater through the heat exchanger because of the air leaking in. If you know how much water you expect to see in the exhaust you may spot that insufficient is being passed through, but all looked OK at first when it happened to me - just the smell of a very hot engine after a while that warned the crew. It was a lesson to me that the sea-water filter only needs to be misaligned by a tiny amount and the engine will overheat badly, a very poor design in my view.

We had another problem with the engine cooling system when the boat was new. We spent some time trying to get the air out of one of the rubber hoses that connects the engine to the water heater - within the closed-circuit part of the engine cooling system. There was clearly an air lock in this hose, as it looped well above the height of the coolant expansion tank and we couldn't get a decent supply of hot water - and this was on a newly-commissioned boat! Also, the level in the coolant reservoir would drop substantially once the engine was started, again indicating that there was air in the system. We eventually succeeded in getting rid of most of the air but the coolant system in this Bavaria has not been well implemented. The reservoir needs to be the highest point in the system and there are two hoses on mine that are above this - one on the engine and the one connecting to the heater. I don't necessarily blame Volvo but Bavaria should have seen the potential problem of air locks and arranged for an extended bracket to be fitted to raise the coolant reservoir. We'll probably make one for our boat when the engine needs a major service.

 

[Bing]

Thanks everyone for your input. Ours is a 2008 Bav 31. We have had numerous consultations with Volvo, who firmly maintain the problem comes from the fact that the engine compartment is not ventillated adequately. The Volvo specifications for the intake air for the motor should be at 25 degrees celcius. We all know that it's far hotter in the compartment. Volvo have spoken to Bavaria about this, and Bavaria were supposed to send us some engine vents but these have never arrived. We have now made extra vents at the top of the compartment to complement the blowers, and we shall see what happens. By the way, the seawater side of the cooling system works fine; no blockages, plenty of water. The problem seems purely on the coolant side. We also have discovered that, if you remove the inspection panel in the rear cabin and the hatch in the head, this solves the problem.....so this definitely points to the ambient air temperature in the motor compartment being too high.

 

[John Nantz]

Bleed Valve on Heater Hose Line

I had a problem like this on our boat:

.... We spent some time trying to get the air out of one of the rubber hoses that connects the engine to the water heater - within the closed-circuit part of the engine cooling system. There was clearly an air lock in this hose, ......

What I did for a fix was to install a bleed valve just before the heater hose goes into the engine. In my case on the Yanmar, it goes in on the thermostat cover. [It's been many years now and this is by memory!].

Anyway, I took a brass "T" and put a couple hose barbs on the straight legs and a small valve on the remaining hole on the T. This allows easy bleeding of the air from the heater hose.

To keep the engine clean I put a small clear hose on the bleed valve so any drips could be bled into a container.

When there is an air lock, one of the problems is not having coolant on one side of the thermostat. Whether this is strictly a Yanmar thing or not, I don't know, but it may be the way the thermostat is designed, too.

The comment earlier about the raw water strainer air leak is a good one. Our strainer has an "O" ring which over the years had got mushed down and I replaced it, which helps. But still, unless the top is screwed down evenly it's easy to get an air leak.

And, of course, the mixing elbow is always a problem area.

Just be glad you don't have twin engines. My brother-in-law has a couple 400hp engines and he's ALWAYS working on them. Just talked to him last night and this time it's one of the alternators! I think this is the third one that just got fried. If it isn't one thing it's something else. Gives him something to talk to the other powerboaters about when they go to their rendezvous! Hey, come to think of it, maybe that's why powerboaters go to so many rendezvous - so they can talk about how to fix all their engine problems!