Volvo D4 Impeller Replacement

[plewis]

Has anyone dared to undertake an impeller replacement on a 29 with Volvo D4? It appears to me that it might be easier to remove the entire sea water pump assembly from the engine, then replace the impeller while the pump is on my workbench. Any ideas or experiences would be much appreciated.

 

[Bill & Donna Sibbers]

I did this myself in June on our 2 year old D4. Yes it was tough, but I'm sure not as tough as removing the pump assembling.

The instructions in the service manual are adequate but does not convey the potential difficulty. I used the following tools:

- Small rachetted box wrench (metric)
- Adjustable plyers
- Philips head screwdriver
- Vise-grip plyer
- silicone spray

First, for the low price of the impeller there is no reason not to replace when "inspecting". It's a bit of work to remove so why not. Once I had the metal cover off I could not get the impeller out no matter what I did - not a great place for finding leverage. So I unscrewed the compression plate and was finally able to pry and pull the impeller out. TAKE A PICTURE of the impeller installed BEFORE you remove the compression plate so you know which way to fold the blades when re-inserting. I suspect they would self correct once turned but didn't want to introduce any uneccesary wear. I re-installed the compression plate and sprayed the cavity with silicone spray (no-oil) prior to inserting a NEW impeller. Everything went back into place easily. For initial startup make sure you have the sea cock open. I ran fresh water through my raw water sump since I had also replaced my engine zincs and wanted to flush any old zinc sludge and the salt out of the cooling system. When starting the engine you will hear a squeal for a few seconds before water enters the pump (which is why I used silicone spray to help reduce the friction).

 

[Scuffy]

You might consider seeking authorized Volvo Penta diesel professional help for the first around as long as you can watch and ask questions. People who deal with these jobs on a regular basis can provide valuable insight maybe worth the price of admission.

 

[plewis]

Thanks much for your interest and instructions. Now that Bill has confirmed that the impeller replacement is physically possible, I'll give it my best shot, after doing some stretching warm ups. If my aged body can't do the contortions necessary to access the pump, I'll be in touch with Volvo - and my chiropractor.

Since the r31 is a slightly larger boat, I wonder if it offers more working clearance than the r29. The sea water pump on the r29 is located under the cabin door coaming, making the only approach from the rear engine.

Among other good advice, the tip about using a 10mm short throw ratcheting box wrench is very helpful and I will order one tonight - along with a hose removal tool, which I think would be knuckle saver.

 

[Lehill]

I replaced the impeller on our D4 R31 this past spring. The impeller housing plate is accessible while laying on top of the engine. Not a difficult job to remove the housing bolts at all. After that the next 45 minutes were spent grunting, sweating and tugging on the impeller with a pair of channel lock pliers. It was much more difficult than I expected to remove the impeller. The new one went in with dish soap for a lubricant and the housing plate reinstalled easily. No issues after this. I then immediately ordered an impeller puller for the next time. That will make the job really simple next time.

 

[ttlmac]

Where do you get an impeller puller?

 

[Lehill]

Have a look on Amazon. Search for seadog impeller puller and get the smaller one. It's a great price.