Inboard performance
- Thread starter Randall Schmidt
- Start date
Yes thanks I did find that page in the manual to be helpful. Was thinking of sharing it to. The manifold has been cleaned by my shop so its on to the fresh water pump (probably do rebuilds) and the heater exchange - these seem to be best advice I've heard. Hope to someday sail rather than work on a marine engine.
What you're looking at on the top port side of the engine is in fact the exhaust manifold and coolant resevoir. The exhaust is the pipe wrapped in insulation. The heat exchanger is a tube shaped object mounted onto the back of the engine. Best way to get at that is likely through the quarter berth reaching over the batteries. There should be one nut holding the end cap on. Remove that nut and the cap to see if there's debris inside.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,174
Randall, I am not a mechanic and what I know I have learned in the past year from books, mechanics, this forum and working on my engine. Having looked as several small diesels, the principals for the most part are pretty much the same. I have a Perkins 4.107 built in the 70's. It is Fuel, Air, Compression and cooling. A bit of battery needed to turn over - start the engine.
The engine had a cooling problem, when I bought the boat. Through discovery I learned it had pestered the previous two owners. Took the Heat Exchanger and all hoses/lines apart cleaning everything, replacing the hoses/lines. Found bits of rubber (likely impeller parts) an undefined slime goo (really ugly booger for a teen movie), and a little scale. Replaced the Closed system water pump on the front of the engine, (similar to a car water pump - the seal was leaking. When I got it off the bearing was gone). Refilled the system with coolant and fired up the engine. I've run it for over 100 hours now and at full throttle temp is rock solid at 165. I check the engine with a laser temp gauge and hottest spot on the engine is 189 at the injector base.
Think you are on the right track to solve your issue.
The engine had a cooling problem, when I bought the boat. Through discovery I learned it had pestered the previous two owners. Took the Heat Exchanger and all hoses/lines apart cleaning everything, replacing the hoses/lines. Found bits of rubber (likely impeller parts) an undefined slime goo (really ugly booger for a teen movie), and a little scale. Replaced the Closed system water pump on the front of the engine, (similar to a car water pump - the seal was leaking. When I got it off the bearing was gone). Refilled the system with coolant and fired up the engine. I've run it for over 100 hours now and at full throttle temp is rock solid at 165. I check the engine with a laser temp gauge and hottest spot on the engine is 189 at the injector base.
Think you are on the right track to solve your issue.
I was having overheating problems on my Westerbeke 10-2. I checked hoses, impeller, HX (found some salt scale which I cleaned out) and couldn't determine why it was overheating. I bought the boat in 2011 (87 O'Day 272 from a reseller (so can't contact original owner). Went to replace coolant in overflow tank and it had not dropped. Found AF had turned to gel. Since I removed HX, all AF had drained from engine. Sucked gel from overflow, blew out overflow line to engine, replaced AF. Not hot anymore. Not sure if AF was low, or AF just not circulating due to gel. AF apparently DOES go bad.
thanks. My antifreeze has been flushed. When I check the heat exchange do I need to drain the coolant first? I imagine the sea water drains when the motor is off. Is there is a drain petcock on the bottom of the reservoir/exhaust manifold? From what I lean online it sounds like I should take the heat exchange to a radiator shop for proper cleaning. Agree? What did you pay for a new fresh water pump or did you rebuild the old one? Where did you buy the pump?
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,174
When you open the Exchanger if not drained coolant will come out.
Not sure about your engine mine did not. I shut the thru hull valve. Some water drained out to the bilge.
Inspect it. Sometimes it is clean just need to blow out or push out any junk stuck in the tubes. About the same size as a 22 gun cleaning rod. I used a wood dowl and air to clean the impeller bits that got stuck. Radiator shop is a good resource based on the part condition.
The water pump. My engine is used in the trucking industry. Went to the Pacific Power, Perkins part distributor of parts for the trucks. They had a rebuilt pump. Think it was about $65. They can be rebuilt. I kept my old part and I'm going to rebuild it so I have a replacement in the future.
Best of luck.
True in general, and true if you remove the HX for cleaning, but on the Universal you can remove that end cap to inspect the seawater passages without affecting the closed loop.
Not on my boat. Universal M25. Same thing with changing the zinc. If the shell of the HX had the coolant, instead of the tubes (which it should), then coolant would drain out whenever you changed the damn zinc. Doesn't happen, does it?
If you are up for it you can clean out the HX yourself using muriatic acid. I have done this and it has worked very well. Google: "muriatic acid heat exchanger" for many hits. I used a 50/50 acid/water mix. Muriatic acid is commonly used to lower ph in pools and is readily available but if you do this be careful because it is quite caustic.
As stated above the coolant will not drain when you take the end cap off the HX but of course it will when you take off the coolant hoses. When removing the HX have a container ready when you take the coolant hoses off the HX and you can drain whatever is necessary into the container.
I bought a new raw water pump from Kumar Brothers. Had an interesting experience in that they had the same pump with a sightly different part number listed in the marine and non marine sections of their web site / catalogue. Needless to say, the exact same pump was a fair bit more expensive with the marine part number. I called them on it and the guy admitted it was the exact same pump. Good price though and it has been working fine for the last couple of years. Easier than rebuilding.
I imagine that on inspection from the end cap I could see if there is crud near that end but could not rule out the HX being clogged in the middle. So, I inspect and see no problem I still to remove it and try and clean it out.
It was suggested that I get a brass rod (like you'd use to clean a rifle barrel) to run thru the HX tubes. The diagram of this part implies that the sea water and fresh water tubes and intermingled like a spring coil. See the diagram earlier in this forum topic stream. A gun barrel cleaner is a straight rod. Are the HX contents also straight rods?
It might say on a plate attached to the pump. This link might help.
http://shop.toadmarinesupply.com/ma...inalcrumb=Universal+Water+Pump+Identification
If it has been more than a few years since the hx was cleaned out I would probably take it off and clean it out.
I think they are all straight tubes. I used a wooden dowel to carefully clean out the tubes.
PS: I know some people don't like to use muriatic acid due to it's aggressive nature. Some have recommended rydlyme which might work well and be safer.
When draining the coolant if there is not drain plug (don't know till I venture back to the boat) I guess I can pull a hose to drain it but that will be tight to fit a receiving bottle underneath it as the hoses I think are pretty short and tight to the motor. Guess I could get a siphon and suck the coolant out. Any advice appreciated. It is an Oday 28 with a M-12 Universal diesel