Volvo Penta D2-55A/B Heat Exchanger Replacement

[MJH]

I just completed this replacement on my Volvo Penta (VP) D2-55B and thought I would pass on my experience to others that have not...it appears to be only a matter of time.

During the summer of 2023 while cruising British Columbia I experienced an engine failure that afterwords learned was caused by a small exhaust leak where the exhaust elbow bolts to the manifold of the Heat Exchanger (HE); a common experience it seems. I say small but over time exhaust plugged my new air filter and killed the engine. After being towed to the nearest port the mechanic located the leak and did a good temporary repair with J-B Weld...it got me home but not trustworthy for distant shores.

Later that year I started enquiring with the local VP dealer what would be involved in the repair. He quoted me $6,365.80 for parts plus labor at $189/hour and taxes. I don't know if his price included the install kit which I didn't know about at the time. I'm guessing there is going to be some daily charge for renting a slip near his shop or in his facility. Labor would take more than one day, much depending on engine access. My wife estimated the total cost would be around $10,000 by the time it is done. Very expensive for a retiree after major house repairs so put it off until this year and decision to do it myself.

Today the U.S prices I found on the Internet range from $5213 to $6456 for part #22898286, the sole replacement for all D2-55 engines (this is essentially the "F" model HE). VP makes a kit for this replacement, #3586996, and prices today ran $514 to $660. Unfortunately, VP doesn't tell you what is in the kit and the dealers I spoke with didn't know either (one dealer didn't even know about the kit), so you could be buying a number of things you don't need if you consider cannibalizing selected parts from the old unit which I did.

There are significant differences between the A/B model and the "F" model HE and if you have made some modifications to the A/B HE setup, like hot water or salon/cabin heater, they will have to be dealt with as well. I found the wiring going to the black control box too short to be affixed at the designated location on the HE and have yet to make a bracket for it. The temperature monitor is located on the forward port side of the replacement HE instead of on the front for the A/B model. I was able to cut open the wiring bundle to expose more wire so that it would reach the sensor, just barely. There is a second port for the temperature monitor further aft on the HE which I just plugger with a short 18mm bolt since I don't have a temperature gauge to power.

In removing the A/B HE, be advised that there are two studs on the upper corners of the HE that most likely will hamper removing the HE, they did mine. They can be removed by double nutting the stud and backing them out; the recessed one will be harder to do because of poor nut access. All other bolts were removed easily. You must also remove the four nuts on the lower forward part of the HE holding the thermostat, they are studded to the block.

Installing the new "F" model HE itself is rather straight forward. The new raw water hose is something to behold with all its turns and bends following the path from forward located seawater pump to the rear of the HE connection, it took us a few attempts before we succeeded (viewing some D2-55F photos or videos on tube helped). I'm still struggling with the two hose clamps for that long hose due to their location and limited access to those areas on my boat. Could it be possible to have the hose installed before installing the HE...Look into it? With the removal of the old HE there will be an unused port on the coolant pump that will have to be plugged which VP sells for a ridiculous price.

If you decide to do this replacement yourself, shop around for the best price while considering sales tax and shipping, sales tax adds up to a bundle itself at those prices. Try to learn what is included in the KIT and if it will be cost effective for you. Study the job in detail ahead of time and give yourself plenty of time.

After reading this you already know more than I did when I started. Good Luck.

[more]

Originally Posted by MJH

I just completed this replacement on my Volvo Penta (VP) D2-55B and thought I would pass on my experience to others that have not...it appears to be only a matter of time.

During the summer of 2023 while cruising British Columbia I experienced an engine failure that afterwords learned was caused by a small exhaust leak where the exhaust elbow bolts to the manifold of the Heat Exchanger (HE); a common experience it seems. now more than I did when I started. Good Luck.

this is easy repair, aluminum welding,later use mile machine workshop. inside must be by hand

bolt is special bolt expensive, dont use SS elbow.
1 hour + 2 hour for coffe brake.

[Dane]

Originally Posted by more

this is easy repair, aluminum welding,later use mile machine workshop. inside must be by hand

bolt is special bolt expensive, dont use SS elbow.
1 hour + 2 hour for coffe brake.

Please describe in more words, what you say. I am not trained in this work, but am about to do it :-) Is it the corroded manifold you suggest to weld? I guess it is cast iron, so can you weld with aluminum? Why do you advice against the SS elbow?

Thanks