heat exchanger/ exhaust elbow

[Croatian Sailing]

swapped a coked up exahust elbow and cleaned out the heat exchanger

[paulemeier1]

i own a D1-30, same problem with a little bit oil under the machine. have it vor 8 years. at first only one whip with aper, in the meantime its 4 or 5 whips with aper.
I have shown a picture to the greatest german volvo penta service point. the chief told me it is the gasket on the backside of the machine. its a non problem. he told me it is not a Bic problem. i only should have a look at the oil. i desidet to repair it if the problem get worth. or if i change next time the sail drive hull gasket.

[sunshine]

Since yours is '07 I assume its a D1-20 (same as mine). Exhaust elbow is easy - just remove the black plastic box thing which is the air filter. One jubilee clip on the inlet manifold, and a "hidden" nut, I think its 8mm, accessed from the back, just below the bottom of the bulkhead using a socket. Once that's out of the way all 4 bolts on the elbow are easy access with a ring spanner. Chuck the elbow and replace with a stainless one from either keyparts or parts4engines. Remember to order a gasket plus another couple as spares. Complications are that the new elbow will probably be shorter so you'll need a longer bit of exhaust hose from either asap supplies or vetus online shop - its the 45mm one. While doing this, replace the exhaust silencer (which will be rusted through and leaking from the aft stainless end) with a plastic vetus waterlock.  If you've taken the end caps off the heat exchanger, order a gasket set from parts4engines which contains 4 of the black o-rings required. Might as well replace the little rubber elbow - its 19mm ID. Get a rubber one online with long tails so you can cut down to size from an online motor factor since the original will be slightly too short for the new elbow. Don't get a silicon one because it will "fold up" on the tight radius and block. Don't know about the oil leak, but check if the raw water pump seals have gone leading to salt water in the bilge. I've been there and done it with all of the above - ideally your previous owner would have too - but look on the bright side that if you chuck some time and money on this now you've got a great boat.

[sunshine]

Also, for removing coolant, there's a little black plastic spigot on the port side about half way up the block towards the rear. Find a little plastic pipe that fits it, slip it on and turn the spigot a few turns anti-clockwise. Put the other end of the hose onto your oil extractor (pela pump etc) and suck the coolant out. Make sure filler cap is off obviously. This is much quicker and cleaner than letting gravity do the work. Use proper green Volvo coolant - I use the concentrate from keyparts plus deionised water from local car access or shop made up  with the correct ratio (from memory I think its 40/60). Hope this helps but PM me if there's anythingD1-20/bav30 specific. I've had mine 9 years and if you look after it, it will look after you.

For working out how things come apart and go back together, the official Volvo penta parts website has exploded diagrams which are pretty handy.

[sunshine]

I didn't extract mine - just pushed a soft wooden stick through each tube from the front.  I think the tube stack can come out forward with some gentle taps from the back end.

[sunshine]

Try this

https://www.volvopentashop.com/epc/en-GB/Details/PentaPartsCatalog/M-D1-H_025?path=MarineDieselEngines%2FM-D1-H%2FM-D1-H_2600%2FM-D1-H_2610%2FM-D1-H_025

[Yngmar]

Wouldn't remove the tube stack just for cleaning, I also cleaned it just fine by pushing each tube through from the front until you can see through them (use a flashlight from behind).

[sunshine]

The brown slime/oil in the expansion tank will presumably also be on the outside of the tubes in the stack. While I wouldn't remove the stack to clean the inside of the tubes,  in this case maybe a one-off clean of the whole thing is merited, but you could probably achieve this by flushing through the whole system with a hose before replacing the coolant. In fact I think the Volvo penta manual suggests doing this every so often.

[sunshine]

I've only ever had light scaling that was easy to poke out, plus I wanted to get the boat back into use as quickly as possible.  I have heard of soaking overnight in "Rydlyme" marine descaler but never felt the need. As long as you have a new set of o-rings to put the stack back in with a good seal, I'd say go for it because then you have the comfort of knowing its been done. For your elbow - that's pretty severe. The surveyor should know these only last 10-15 years max so should be swapped out at this stage. How does the raw water pump and piping look? The pipes can go a bit hard and split, especially if the hose clamps are overtightened and dig into the plastic. Its a nice job to change them all. The pump seals go and need changed when you see a drip coming from the tell-tale begin the impeller housing. If left too long the shaft scores and you need a pump overhaul (new shaft and bearings) although there is a cheap fix using a twin- lip seal.

[sunshine]

For the water pump seals - there are two. The front one keeps raw water in the impeller body and is usually the first to go. It lets water behind it which then drips out of the hole. The inner seal keeps oil in the engine side. If both seals are gone its possible you get water and oil leaking. If only water, then you can replace the seal from the front - use some screws into the seal and pull it forward. Replacement seal slips over the shaft and push it into place using e.g. a socket of the correct size. Use a generic (not Volvo) seal for around E2. If the shaft is scored where the seal sits, you can get a seal with two lips that will sit nicely either side of the score on the shaft. I got this from simply bearings in uk for £5. Description is "12x24x7mm TCI/R23 Double Lip with Bi Directional Feature Viton Rubber Metric Rotary Shaft Oil Seal with Garter Spring".

If the oil seal at the back is also gone, you need to take the pump off. Its an awkward job since its bolted in from behind but definitely do-able with patience. If doing this, replace the bearings while you are at it.  You can get a refurb kit from Volvo which includes a new shaft, bearings and seals for around half the price of a new pump.

I've never cleaned the diesel tank, but I have a fitting that reaches down to the bottom of the tank from the top that I can suck out any water/gunk using my oil extractor pump. I occasionally draw a sample and let it settle in a glass jar and see a very small amount of water, but never anything nasty or black gunk.

[Yngmar]

Checked the coolant? Is it still coolant and not diluted/replaced with seawater? Level okay? Are there clumps in it?

Because:

Older D1-20 diesel engines may run on Volvo green coolant and newer ones may be using yellow VCS coolant. Please do not mix or change the coolant type once one or other has been used. If you are running on Volvo Penta green coolant, continue to use green coolant. Mixing yellow and green coolant can cause gelling and blockages within the cooling system.

So your ill advised change of coolant may have lead to blocked coolant passages in the engine casting [Source: https://fybmarine.shop/volvo-penta-d1-20-service-and-spare-parts]

[sunshine]

It feels like you have done most of the raw water side, so could be on the coolant side. You are right to query the thermostat - could be that its either not opening at correct temp, or not opening fully. I have a feeling you can take it out of the heat exchanger without taking the exchanger off completely. Usual test is to place it in a pan on the stovetop, bring slowly to the boil and see when/if it opens.  You can also try running the engine with the thermostat removed and see if that helps.

If the coolant is not circulating, the calorifier won't get a feed of hot water, so when your engine is hot, what is the temperature of the hot water from the tap in the galley like?

The other possibility is the coolant pump failing to circulate coolant through the system, although usually the bearings  go causing a squeal but the pump still works.

[Yngmar]

Makes sense to check the thermostat next, as that should be easy to remove and see and if you did end up with mixed coolant (easy to miss some in the engine passages - did you run the engine to flush or just flush through by filling/draining?). While you have it out you can also test the thermostat in a pot of boiling water and see if it opens/closes correctly (IR thermometer gun is a useful tool).

Apparently this is a common mistake in car engines also. Plenty of advice and photos on the internet, e.g. these, showing jelly that could block the thermostat from opening: https://mgaguru.com/mgtech/cooling/cool_121.htm

Should I merge this thread with the other one?

[Krumelur]

Had a similar experience on my Bav 40 after changing out the elbow.
Recently, I refurbished my original VP sea water pump. Was on a D2-55, though.
Toughest part was getting the cogwheel off using a gear puller. But aside from that I was able to buy all spare parts at "Go-Glas" - a provider of automotive parts. Total was €20 compared to much more when buying a third party refurbishing kit.

[Krumelur]

What I meant was, I also noticed more seawater dripping after the exhaust elbow change.
I did not do anything else, no cleaning product. Just replaced the elbow with a stainless steel one from HDI Marine (USA).

[sunshine]

Not quite. If the shaft is in good condition, then yes, but if its scored where the front seal sits, you can still get a small leak when the new seal sits on the score, so you need to get the Volvo kit which also includes a new shaft. Its an awkward job to get the pump off, so there is the option to just try changing the front seal from the front with a double-lip version first and go sailing this summer and leave the full refurb for the winter.  From your video, you can see one of the pump studs is a bit rusty, so the pump has maybe been leaking for a little while.  I think you are doing a great job of sorting out all of the maintenance items that the previous owner would ideally have done, so you will be in a great place going forward of having done these things and also have great knowledge and experience of the engine side of things. 👍

[sunshine]

Also, consider changing the hoses. I did all the work sorting a leaking pump, and it turned out the real problem was the thing shown in this photo!

[Krumelur]

Before I refurbished my old pump I got a replacement 3rd party one which I installed. I’m keeping the original one as a spare part.
Just another alternative.

[paulemeier1]

Also, consider changing the hoses. I did all the work sorting a leaking pump, and it turned out the real problem was the thing shown in this photo!

thank you very much for this advice. will have a look at that. was the position in front of the head exchanger?

[Petef]

I've only ever had light scaling that was easy to poke out, plus I wanted to get the boat back into use as quickly as possible.  I have heard of soaking overnight in "Rydlyme" marine descaler but never felt the need. As long as you have a new set of o-rings to put the stack back in with a good seal, I'd say go for it because then you have the comfort of knowing its been done. For your elbow - that's pretty severe. The surveyor should know these only last 10-15 years max so should be swapped out at this stage. How does the raw water pump and piping look? The pipes can go a bit hard and split, especially if the hose clamps are overtightened and dig into the plastic. Its a nice job to change them all. The pump seals go and need changed when you see a drip coming from the tell-tale begin the impeller housing. If left too long the shaft scores and you need a pump overhaul (new shaft and bearings) although there is a cheap fix using a twin- lip seal.

Do not go to a Penta agent for your O rings, it cost me £64.00 for the set of 4. I'd have refused to pay but I wanted to get the engine back together as launch day was approaching, I'd lost one of the original rings so couldn't re use them (not that I wanted to).

As for the heat exchanger Once the ends were removed (which meant Exhaust elbow, air filter and coolant reservoir to on my D1-30) there were bits of old impellers that I removed that were partially blocking the exchanger and then gently pushed it out from the back forwards.

I soaked the exchanger in White vinegar (54p a litre) overnight and then used a piece of flexible plastic covered curtain wire to push any stubborn bits through. According to the workshop manual Volvo suggest you dump the old exchanger and get a new one for £999.00! versus 54p.

My hose split just above the raw water pump when I handled it (fortunately on the hard) so I've replaced all the sea water hoses on my 2008 B34.

My pump seems ok but will keep an eye on it, I'd like to understand more about your cheap fix re twin lip seal.

Update 5/8/22: Noticed there was a asmall pool of water a few days ago under the raw water pump. After wiping the pump dry, the drip was coming from behind the impeller. So it looks like the water seal has gone. Sent for a replacement (2 seals + gasket £10) what was sent was too big. Asked one of the marina boat yard guys where I might get one locally. He pointed me to a small 'O ring and seal" shop (East Anglian Bearing Service Ltd, Ipswich). Two seals less than £5! Tried to remove the old seal using a wire and poking it from the holes in the back, couldn't shit it so put a small diameter but long screw carefully into the old seal and gently eased it out. he new one was bugger to insert, used the old seal on the shaft behind the new one and the a socket over the shaft and pushed it as far as I could. But it wasn't in enough so ended up using a hammer to get it home. Glad I used the old seal as a buffer as it was distorted when I removed it. But the new seal was in place.
   

[sunshine]

thank you very much for this advice. will have a look at that. was the position in front of the head exchanger?
[/quote]

The split in the pipe was where it attached to the inlet (bottom side) of the water pump. It was under the hose clamp so hard to find.  The pipe had gone hard/brittle and the clamp had bitten into it causing the split.

[sunshine]

My pump seems ok but will keep an eye on it, I'd like to understand more about your cheap fix re twin lip seal.

Just Google "12x24x7mm TCI/R23 Double Lip with Bi Directional Feature Viton Rubber Metric Rotary Shaft Oil Seal with Garter Spring" and you should find them on the simply bearings website. Because the seal has two lips, these sit either side of the score on the shaft, so you can avoid replacing the shaft if scored.

[Yngmar]

Also can sleeve the shaft with a speedi-sleeve, invented for exactly this purpose. Helps if you've already done the twin lips trick and have three scores on the shaft now

[sunshine]

Just left it as standard since I didn't have any problems with the coolant side. On youtube, there is a channel called Cactus Sailing who did this to a Bav30. In fact, I think Cactus is on here - you could PM him.