Logo
FULL SITE MENU

225 overheat after service

R

Reel Steel

Member
I just completed my annual maintenance on my twin 2006 BF 225's. This year I did the internal zincs in addition to new water pumps, thermostats, filters etc. Did the intermediate shaft bushings also. The valve adjustment held steady the last 2 years so I skipped that this year. The engines have about 2500 hours. I got an overheat alarm on one of the engines at while running about 1500 RPM. That engine does not have as strong a stream coming out of the indicator as the other engine. It ran at 5500 RPM with no problem. So where should I start looking? There was some salt buildup around a couple of the thermostats as well as some around the zincs in the exhaust manifolds. The left hand manifold was warmer to the touch than the right hand.
 
Well if you run it in the ocean then there are two area's that will need attention. First the pressure relief valve's are below the cylinder head's both port and stb. The plunger will stick open because the grommet will swell up due to corossion not allowing the block to properly fill. This can also be verified with removal of thermostate cover's. Crank engine on trailer, backed in at landing. NO GARDEN HOSES. If their is a good head of water at idle then you may have the second issue. Next, remove the plastic side pannel's, look at the bottom of the exhaust manifold's there is a black rubber hose. Those are the main water outlet's. What happen's is corrisson will swell and shut the water outlet off. Move clamp on hose to release tension and pull hose out from mount case. They will need to be replaced. Best of luck. Thanks Martin
 
Yep, only at idle speed. I know it doesn't sound right but it is a real world test. Be very safe becauseof the exposed belt and other mechanical hazard's. Stay Safe Martin
 
Yep, nothing that a garden hose can't wash off. But your unit's after being used in that enviroment should have a thick coating of corrosion preventive already sprayed on them. If not LPS-2 Is the absolute best or steal your wife's can of spray PAM out of the kitchen cabinet. It work's great and good for the enviroment. Thanks Martin
 
Update... Was out of town for a few days but now I'm back on the boat. I have a new clue. There is a stream of water coming from somewhere behind the high pressure fuel filter when flushing the engine. Tomorrow I will remove the cowlings. Right now it almost looks like it is coming from the head gasket. I only removed the exhaust manifolds so that is where I expected to see the problem. I'll know more tomorrow. Thanks again for the pointers.
 
NA!!. You gave the clue away. The cooling hose for the V/P has ruptered. Common failure. Hose from mount case to vapor seperator cooling manifold. Thanks Martin
 
Well, the news could hardly be worse. There is a hole about one eighth inch in diameter in the engine block below the intake. It appears to be a casting flaw. The worse part is that it is in such an awkward location that I can't get any tools to it.
 
Last edited:
Yea, I would hate to say it again however it's another common failure. I have seen many failures as you have mentioned. There are ban-aid's that are cheap but will fail again. The auto part stores sell an item called JB weld. It's a two part epoxy that work's well, if applied properly. You will need some type of die grinder or Dremel tool to remove the paint and corrison. This can turn into a "can of worm's". At this point you will need to make some hard decision's. The corossion monster is eating your unit from the inside out. I suspect that the mount case, and head gasket mating surface's have suffered the same. Honda has known about these issue's but anode's to combat this, didn't come untill the 2010 year model. If I were you, bring your unit to a Honda Marine dealer, show them what you have found. Express your concern. Of course, be a gentlemen. Then request that they report this to the customer relations dept. Then you call Honda and express your concern's. You must have your serial number when you call. Wish you the best. Martin
 
Thanks again Martin. I was able to run a 5/16 tap into the hole. I cleaned it as you suggested and used JB Weld and a 5/16 SS screw to fill the hole. I had a welding shop for 20 years and hated JB weld but this repair should hold for a while. When I had the exhaust manifolds off I did not see any corrosion so this kind of surprised me. Anyway I always hated to weld on an engine block that wasn't going to be machined afterwards. Like you said, time for some hard decisions.
 
Back
Top