D1-30 / Oil Pressure alarm

[CRYSTAL]

Got an interesting one.

Got a B33-C late 2006 model with D1-30 with low engine hours about 700. Prop is Volvo alum 3 blade (14x12) and matches with max RPM (3100) and about 7.3kts speed in calm waters.

said that, I fully services the engine last month (Oil / filters / impeller looked good so no change). Hull is crystal clean as well.

now coming to the issue: Last week I decided to test the engine / boat by reving up to 2500RPM for an hour until we got close to our destination which I then put the metal to the floor to full 3100RPM. within few minutes, I got the coolant light on and I switched off the engine. Checked the coolant level and all goo - just above min level.
Turned the engine back on, and now getting the Oil pressure light. Kept the revs down to 1500 and oil alarm went off. checked oil and no issue - level is at about 10mm above max (funny enough i had removed the full oil out of the engine and put back in 3.5L as suggested in the manual).

The oil level being slightly high is not an issue as per Volvo Service but they also have no idea to why this happened.

Another thing is that this is the first time I'm trying such high revs for longer then half hour as my usual revs are between 1800 an 2200 for cruising. I only momentarily go high revs and no issues.

One unusual thing I have noticed: when engine is off, the coolant level is at Max. when engine starts, the level drops to just above min. Why? I have changed the coolant 3 years agao and seems in very good condition and no loss.
I'm wondering if the 3 bladed prop is affecting the engine as well but Volvo is saying it shouldn't as it's the right specs for it.
would also be nice if I had a Temperature Gauge to see the actual temp of the coolant.

Any advice would be appreciated.

Thanks,
Hratch

[IslandAlchemy]

The low oil pressure is probably simply because you got the engine really hot, and so it thins out. I'm sure that once the engine has cooled off again it's been fine. Driving it at maximum revs for an hour is going to get the engine very hot.

[CRYSTAL]

thanks, but I was doing 2500 which is well under the max of 3200 as stated by Volvo manual.
Just to clarify, I was on 2500 for one hour and then flat out only for few minutes.
Basically, we might be right in saying the engine got hot and oil thinned out but if you are in heavier weather, you'll need to punch the waves and will need min 2500rpm. and when the need arises, shouldn't you be able to punch it to 3000? I guess the best thing is to install oil pressure gauge and temperature gauge to see exactly what's going on. Just an alarm is not enough to troubleshoot. Last thing I want to do is to open up the heat exchanger for any debris  but I have never found a missing impeller pieces to this date.

[dawntreader]

Don't worry about taking the heat exchanger apart - it is a simple operation to open, clean and replace. There are three bolts holding the front cover and once these are freed the cover can be [gently] prised off.  I had a cooling issue and, like you, didn't notice any impeller bits missing. When I took the front cover off the heat exchanger it was full of junk that had got past the raw water filter - including bits of impeller blade.

Cleaned it out then and now regularly do this as part of my annual service - not had any heat issues since 

[willfinch36]

Don't worry about taking the heat exchanger apart - it is a simple operation to open, clean and replace. There are three bolts holding the front cover and once these are freed the cover can be [gently] prised off.  I had a cooling issue and, like you, didn't notice any impeller bits missing. When I took the front cover off the heat exchanger it was full of junk that had got past the raw water filter - including bits of impeller blade.

Cleaned it out then and now regularly do this as part of my annual service - not had any heat issues since 

Thanks for the advice, I was getting an overheat alarm when the engine was really being pushed for a bit, let the engine cool down for a minute and it was fine. I will take the front cover off and inspect. Did you flush it out with any sort of descaler?

[CRYSTAL]

Thanks, but what about the O rings or gaskets once you remove the cover?

Can someone confirm the following: whats the coolant level prior engine start and again post engine start? Why would it drop from max to min within seconds?

Very weird and makes no sense. Next job is to try to blead the system.

Tnx,

[dawntreader]

Attached diagram of heat exchanger unit. Item 3 is plastic (on my engine) and I only removed this cover. Sealing ring (item 7) was in good condition and was lubricated with silicon grease before re-assembly.

Coolant water level is marked on the reservoir. Once engine is started it is pumped into the system. Some of the chambers will be empty and so the level appears to go down. When engine stops these chambers drain and level returns to 'normal'. If you were able to check your oil level the same way you would see the same effect. Personally, I would be worried about over-filling as liquids do not compress and you can do serious damage to your engine if you do. Good job Volvo seem to have a 'safety margin' on the dip stick. 

I have the D130b in my B37 and if I push too hard for too long I get the overheat issue too. Design speed and reality seem to be adrift 

[dawntreader]

Diagram of exchanger attached here

[Trapeze Artist]

I have a D1/20 which is presumably very similar. It has given me occasional grief on the overheat front, invariably in an already difficult situation.

Could you clarify the cleaning process a bit?

• Drain coolant
• Take off cover (item 3)
• Withdraw the heat exchanger matrix?
• Clean, reassemble, refill

Something like that? No need to remove the cover at the other end (item 4)?

[dawntreader]

For a 'quick' clean you only need to do the following:

• Remove raw water intake from front cover
• Remove 3 retaining bolts
• Prise/tap off front cover (gently
• Remove any obvious debris and inspect cooling tubes for cleanliness
• Lubricate o-ring (item 7) with silicon-based grease
• Refit in reverse of above (cover bolts only 'finger nipped tight' - don't over tighten)

I see no reason to remove the whole assembly unless significant blockage of the tubes is evident. These can be tested with a long probe. There should be no calcification (sea water is 'soft') so no flushing is necessary and, as the main assembly is not removed, no need to drain the coolant [not sure if this would be necessary for full dismantling anyway). I would also suggest it is not necessary to remove the rear cover as any debris getting through the tubes will pass into the exhaust system and be flushed away.

Hope this is useful.

[Ripster]

For a 'quick' clean you only need to do the following:

• Remove raw water intake from front cover
• Remove 3 retaining bolts
• Prise/tap off front cover (gently
• Remove any obvious debris and inspect cooling tubes for cleanliness
• Lubricate o-ring (item 7) with silicon-based grease
• Refit in reverse of above (cover bolts only 'finger nipped tight' - don't over tighten)

I see no reason to remove the whole assembly unless significant blockage of the tubes is evident. These can be tested with a long probe. There should be no calcification (sea water is 'soft') so no flushing is necessary and, as the main assembly is not removed, no need to drain the coolant [not sure if this would be necessary for full dismantling anyway). I would also suggest it is not necessary to remove the rear cover as any debris getting through the tubes will pass into the exhaust system and be flushed away.

Hope this is useful.

Very useful, thanks.  I have the same D130 unit near enough and have this inspection on my list to do.

[Trapeze Artist]

For a 'quick' clean you only need to do the following:

• Remove raw water intake from front cover
• Remove 3 retaining bolts
• Prise/tap off front cover (gently
• Remove any obvious debris and inspect cooling tubes for cleanliness
• Lubricate o-ring (item 7) with silicon-based grease
• Refit in reverse of above (cover bolts only 'finger nipped tight' - don't over tighten)

I see no reason to remove the whole assembly unless significant blockage of the tubes is evident. These can be tested with a long probe. There should be no calcification (sea water is 'soft') so no flushing is necessary and, as the main assembly is not removed, no need to drain the coolant [not sure if this would be necessary for full dismantling anyway). I would also suggest it is not necessary to remove the rear cover as any debris getting through the tubes will pass into the exhaust system and be flushed away.

Hope this is useful.

Thanks.

[CRYSTAL]

Excellent info tnx.
Just finished bleading the system and now the coolant level is sitting between max and min. Perfect.

Will inspect the 'noodles' next.
So nobody suspects the prop then as my initial comments.

Regards

[dawntreader]

When cleaning the exchanger you may also wish to replace the rubber o-ring (Volvo part number 3842016 for the D1-30B) if it has gone hard. These are £10 each plus postage from Volvo. However, I have sourced them here: www.simplybearings.co.uk

The items are BS838.NBER 3.53mm section 61.9mm Bore Nitrile rubber o-rings. The specification for Nitrile is on the same site so you can check its suitablity yourself. These are £4.91 for 2 including p/p and tax 

[CRYSTAL]

Yep, had to order from VP as I had to destroy the back end ring while pulling the HE. I think they charge me EUR45 for the set of 4.

Ur site is excellent and would cost me gbp14 with the pack of 10 and fedex delivery.
Must check exact size and keep these as  spare parts.

Why is it so hard to pull the exchanger out? Or is there a trick?

BTW,  issue resolved after fully cleaning HE, exhaust elbow, relocate expansion tank above engine. Added precaution was also install shut off valves for the hot water boiler tank. engine warms up much faster when circulation is cut off for hot water. Can always turn them on after 30mins or so if u need it but in the med during summer, dont need hot water.
Good also to isolate coolant between hot water and engine and for emergency engine cooling (if ur tank is cold). 

Regards

[battuta]

Ahoy Crystal!

Can you further explain (and perhaps include a photo) exactly what you did to isolate and install shut off valves for your hot water tank?

Thanks in advance.

[CRYSTAL]

hi there,
very simple actually. Did not want to pay premium VP prices so I bought half inch valves for both ends with tailpipes fitted for the coolant pipes + 90 degree tailpipe at the pump side . See pics.
Also raise you're expansion.tank as per picture if you're Hot water tank is higher than exp tank mater a huge difference

regards ,