Need help ASAP with cracked Volvo penta 55

[Mitchell87]

Hi, I just recently purchased a catamaran with two Volvo penta 55’s. The engines have aproximately 2500 hrs each. I fired up the port main today and noticed lots of exhaust coming out the engine room hatch. I discovered that the part of the block where the block meets the raw water discharge hose has a large hole in it. I’m assuming from corrosion. Water was shooting out into the engine room bilge. Has anyone experienced this? Can this be fixed or do I need a new engine?

Thanks,
Mitchell

[redbeard1]

Hi,

Is the hole in the yellow area or red area? If yellow, replace the exhaust riser. If red, maybe others can comment on welding block.

[Mitchell87]

The hole is in the red area just inside where the part in yellow bolts on. So that entire piece is the heat exchanger correct? What do those cost to replace?

[redbeard1]

hi,

I don't have much direct experience with that engine. If it is similar to the one that I am linking, I would guess that part is pricey although once you have the part number, you might be able to find a similar part for less.

I would go to the main site on the link I am providing, look up your exact engine (there always seem to be many variations, go by the serial number that is labeled on your engine), and look up the part.

https://www.marinepartseurope.com/en...0-26-5493.aspx

[Lepke]

Try ebay for a used part. There are several makers of replacement heat exchangers. Some look like the original and some need some plumbing.
Custom & Stock Marine Heat Exchangers & Cooling Systems - Orca, WA
http://www.seakamp.com/
Lenco Coolers - marine heat exchangers, marine oil coolers
Marine Heat Exchangers Manufactured by Bowman | EJ Bowman
Marine Heat Exchangers
https://turmarmarine.com/ami/index.asp

[Scout 30]

I hope you're sitting down when you get the price.

[DougR]

The part circled in red is a casting that functions as a combination exhaust manifold and heat exchanger housing. There were two types; the earlier, as shown in the photo, was found on the D2-55 A & B, and a second type was used on D2-55 C and later.

These castings are made of aluminum and normally do not touch sea water, only antifreeze, so it may be fairly straight forward to have the crack welded. However there are intricate interior coolant and exhaust passages so it would be best to have things pressure checked.

From your statement " there was water and exhaust shooting" it sounds like perhaps the housing is cracked or holed across both the exhaust and antifreeze passages.....

DougR

[Mitchell87]

Originally Posted by DougR

The part circled in red is a casting that functions as a combination exhaust manifold and heat exchanger housing. There were two types; the earlier, as shown in the photo, was found on the D2-55 A & B, and a second type was used on D2-55 C and later.

These castings are made of aluminum and normally do not touch sea water, only antifreeze, so it may be fairly straight forward to have the crack welded. However there are intricate interior coolant and exhaust passages so it would be best to have things pressure checked.

From your statement " there was water and exhaust shooting" it sounds like perhaps the housing is cracked or holed across both the exhaust and antifreeze passages.....

DougR

Here is a picture of the hole. Interesting that you say it’s aluminum, because it’s sure rusty looking.

[DougR]

Photo of the hole didn't stick......try it again.
DougR

[Mitchell87]

Let’s see if this works

[kmacdonald]

Looks like part # 3808561 if C version. About $3,700
Volvo Penta HEAT EXCHANGER 3808561 - Marine Parts Express

Check to make sure that is the right part for your engine.

[agb512]

I'd say DougR is correct that it is aluminum. The elbow is cast so looks rusty. I'd take it off and have it welded then machined flat. Probably started with a pin hole that grew with exhaust gasses. Might work.

[OzDean]

Hey Mitchell, I recently replaced the "3808561 heat exchanger" on D2-55 for the same issue. I have attached the pictures. The new part was quoted around 3.5kEUR, but it would have taken weeks to arrive and the cost made me spill my beer, turned out there was a second hand one available for 2.1kEUR, apparently this is a common problem on the D2-55. The work was done in Turkey at Antalya, the labour was EUR175. Since then I have planned to install a T valve on the cooling intake just before the filter, then lead the hose up to a 8L plastic container that I can fill with fresh water. Then I can flush the sucker regularly to stop this happening again. Also, for winterising I can fill the 8L container with green coolant etc and turn the motor over for 10-15 seconds to leave positive pressure coolant in the heat exchanger when the motor is not being used. Well that is the plan, spurred on by not wishing to spend another AUD 5k. I wonder has anyone else installed a fresh water flushing system along these lines. The motor was 15 years old but had done under 1000 hours, the issue I was told is from having it not being used enough.

[TheThunderbird]

Dean! that's an Academy award winning suggestion

Love it !!!

Thank you

[OzDean]

Thanks ThunderBird, have just done some research with Professor Google and their are flush kits designed for inboard closed/open cooling systems so that makes it easier, I will start a new thread asking if anyone has used these kits, for example How it works - Quick Flush Valve System - boat engine flushing, winterizing and emergency bilge pump kit, Gas, Diesel, Out Drive Marine Engines, Generators, AC units