Scuffy
Well-known member
- Joined
- Mar 5, 2015
- Messages
- 473
- Fluid Motion Model
- C-28
- Hull Identification Number
- FMLT27161
- Non-Fluid Motion Model
- Float On Tandem Axle Trailer
- Vessel Name
- Tinytown
- MMSI Number
- 338190746
Our boat a 2014 R27 with a Volvo 200 hp D3 has about 200 hours on it currently. Last year while boating in the Pacific Northwest we experienced slowly climbing engine temperatures when running above 3300 rpms. The temps would immediately drop by reducing rpms. We have the impellor changed every spring. So while in Marathon in the Florida Keys this month I had Marathon Boatyard in Marathon (an authorized Volvo Penta service center) do an impellor change and switch out the engine the raw water pump belt along with the second engine belt which drives the alternator. At the same time check the raw water belt tensioner. I mentioned to Juan the mechanic from Marathon Boatyard about the higher than normal engine temperature at higher rpm’s. He immediately closed the thru hull to the strainer basket and pulled the raw water hoses off the transmission cooler. The raw water hose comes out of the strainer basket and goes around the engine and connects to the port side transmission cooler located at the rear of the engine on top of the transmission. On the starboard side of the transmission cooler that hose carries the water that passes thru the transmission cooler to the raw water pump.
Once Juan had both hoses off the trans cooler he took a water hose on the starboard side of the transmission cooler to back flush seagrass other debris from transmission cooler that had gotten through the raw water strainer. He held a plastic Folger coffee container to catch the out flow on the port side of the transmission cooler. He used a pick to loosen any sea grass on the port side of the cooler while back flushing out the disc located inside the transmission cooler which looks like a smaller metal version of the white plastic discs that come with the boats for the scupper drain system. He kept picking and flushing until after many fill ups and dumps the coffee container just had clean water with no seagrass or foreign matter was seen in there. This sea grass caused a restriction by partially clogging the disc with holes in it thus restricting the full flow of water getting through the transmission cooler onto the engines raw water pump. The impellor that was removed looked perfectly normal. Once you know about the possible restriction in the transmission cooler it’s an easy thing to check and correct. It was also recommended that I carry a raw water belt tensioner in our selection of replacement parts. Because of the salt water environment and close proximity of the bilge area raw water belt tensioners seem to corrode and will seize up. The other belt tensioner for the alternator belt does not seem to be effected. A replacement raw water belt tensioner is about $181.00 dollars. It was recommended the next impellor change to also replace the raw water belt tensioner.
I attended the Volvo seminar at Roche Harbor and I think this was something they should cover the above in the future. Especially since I spoke to the factory speaker about this very same issue. I never knew there was a possible restriction in the trans cooler. I hope this helps some to be able to apply the simple fix to clean the strainer located in the transmission cooler. If your temperatures go up more than normal running at higher rpm’s checking strainer in the transmission cooler would be a great place to start.
Once Juan had both hoses off the trans cooler he took a water hose on the starboard side of the transmission cooler to back flush seagrass other debris from transmission cooler that had gotten through the raw water strainer. He held a plastic Folger coffee container to catch the out flow on the port side of the transmission cooler. He used a pick to loosen any sea grass on the port side of the cooler while back flushing out the disc located inside the transmission cooler which looks like a smaller metal version of the white plastic discs that come with the boats for the scupper drain system. He kept picking and flushing until after many fill ups and dumps the coffee container just had clean water with no seagrass or foreign matter was seen in there. This sea grass caused a restriction by partially clogging the disc with holes in it thus restricting the full flow of water getting through the transmission cooler onto the engines raw water pump. The impellor that was removed looked perfectly normal. Once you know about the possible restriction in the transmission cooler it’s an easy thing to check and correct. It was also recommended that I carry a raw water belt tensioner in our selection of replacement parts. Because of the salt water environment and close proximity of the bilge area raw water belt tensioners seem to corrode and will seize up. The other belt tensioner for the alternator belt does not seem to be effected. A replacement raw water belt tensioner is about $181.00 dollars. It was recommended the next impellor change to also replace the raw water belt tensioner.
I attended the Volvo seminar at Roche Harbor and I think this was something they should cover the above in the future. Especially since I spoke to the factory speaker about this very same issue. I never knew there was a possible restriction in the trans cooler. I hope this helps some to be able to apply the simple fix to clean the strainer located in the transmission cooler. If your temperatures go up more than normal running at higher rpm’s checking strainer in the transmission cooler would be a great place to start.
