Big Keepers
Petty Officer 1st Class
- Joined
- May 13, 2007
- Messages
- 293
***** EDIT *****
Okay I pulled the thermostats out and started up the engine. I waited about 10 seconds and no water was coming out where the thermo's go. I pulled the lower unit off and checked the inlet pipe that fits into the water pump housing. It seemed okay, not loose or broken. It had plenty of grease around the outside so I know it was in the grommet.
I took a hose and started to fill the thermostat ports with cold water. Water started to trickle down the outside of the intermediate housing a bit where the cowling surrounds it. I didn't notice anything coming out the water inlet tube. So I put the nozzle on the hose and sprayed water up the inlet tube. I didn't go full blast, I slowly increased water flow until I had water pouring out the thermostat housing area, it was coming out the telltale as well. Before I took thermo's out I ran the motor for about a minute and I wasn't getting any water out the telltale or the hose or the nipple on the exhaust cover. The pressure relief spring is perfectly fine and the plastic piece inside is too. There was a small piece of gasket material in there and some dead flies. That's it.
So here is the question then, inside the intermediate housing you can only see about three inches of the water inlet tube before the bottom of the housing is there. Up inside that intermediate housing is the rest of the tube. If it was totally broken off would I still have gotten water out the thermostat housings? If it has a decent crack in it will it lose enough water to not get any pressure up to the thermostats? When I took the thermostats out they were wet so some water has to be in there someplace. From what I can tell looking at the inlets where water goes into the jacket covers, there is no blockage there.
I'm about to go digging into my manual again but is there any way to get the intermediate housing off without pulling the powerhead too? I can do this stuff if necessary but it will be a major problem as I don't exactly have all the tools and an engine hoist at my command. I know this much if the intermediate housing comes off I will change the shift rod too.
I read some of the other threads about overheating and fixing the problems. I'm having similar issues with my outboard. I just had the lower unit serviced, I had drained half a quart of milk water from it. The shop resealed it and put in a new impeller kit. Prior to that I tried to run the motor and it overheated. I saw the impeller was shot so I figured that was the problem. Now I still have overheating issues so I'm trying to figure out where to go first before I start taking water jacket covers off and possibly snap old rusty bolts. When I put the lower unit back on I also put two new thermostats in. Something else to note is I use the rabbit ears where water splits to both sides. I also have the smaller pair where the water comes out one side and the other is just a muff to block the other intake. The hose from the house seems to put out plenty of water when I wash my boat and stuff but I figured I'd throw that out there. I'm half wondering if my rabbit ears could be a source of bad water flow too. When I turn on the water full blast it seems to come pouring out the sides of the ear muffs. When running I can't tell where water should come out with exhaust but it seems to exit the hub in the middle of the prop.
I'm seeing this motor has a pressure relief spring at the bottom of the exhaust cover between the two cylinder banks. My questions are:
1.) How likely is this part to fail and how often is it usually serviced/replaced? The thing looks pretty flimsy in the manual but no instructions are stated for maintenance.
2.) I'm assuming and hoping that some larger particles that may have broken off the impeller would possibly get trapped there and cause a poor flow of water.
Before the lower unit servicing, no water came out of the telltale and cylinder temps shot up to almost 200? quickly. This time some water came out of the telltale although it was without pressure and when I took the hose off it, water kind of dribbled out of the hose. The temp on the thermostat cover was about 15? lower than the temp on the head cover. Both port and starboard banks overheated at the same rate. On both banks the lowest cylinders (#5 & #6) seemed to run cooler than the ones above them at first then caught up when temps got above 175?.
I'm definitely going to look at that pressure relief spring tomorrow morning. After that I need cylinder head cover gaskets and those come off for a cleaning. Probably the heads themselves also.
Suggestions on where to start please. As I said if I can avoid having to remove the covers and such I would like to. Also when I took the lower unit off to bring to the shop I removed the impeller. It did not appear to be missing any pieces. The vanes were cracked themselves yes and the outside edges started to flatten out but it seemed intact. Also the mechanic told me that the lower unit itself is basically an empty cavity that fills with water thru the intakes. He said there did not seem to be any blockage or anything wrong down there so I'm thinking my problem lies someplace between the impeller (possibly a faulty install) and the new thermostats I installed. Could both banks have totally clogged water passages?
Okay I pulled the thermostats out and started up the engine. I waited about 10 seconds and no water was coming out where the thermo's go. I pulled the lower unit off and checked the inlet pipe that fits into the water pump housing. It seemed okay, not loose or broken. It had plenty of grease around the outside so I know it was in the grommet.
I took a hose and started to fill the thermostat ports with cold water. Water started to trickle down the outside of the intermediate housing a bit where the cowling surrounds it. I didn't notice anything coming out the water inlet tube. So I put the nozzle on the hose and sprayed water up the inlet tube. I didn't go full blast, I slowly increased water flow until I had water pouring out the thermostat housing area, it was coming out the telltale as well. Before I took thermo's out I ran the motor for about a minute and I wasn't getting any water out the telltale or the hose or the nipple on the exhaust cover. The pressure relief spring is perfectly fine and the plastic piece inside is too. There was a small piece of gasket material in there and some dead flies. That's it.
So here is the question then, inside the intermediate housing you can only see about three inches of the water inlet tube before the bottom of the housing is there. Up inside that intermediate housing is the rest of the tube. If it was totally broken off would I still have gotten water out the thermostat housings? If it has a decent crack in it will it lose enough water to not get any pressure up to the thermostats? When I took the thermostats out they were wet so some water has to be in there someplace. From what I can tell looking at the inlets where water goes into the jacket covers, there is no blockage there.
I'm about to go digging into my manual again but is there any way to get the intermediate housing off without pulling the powerhead too? I can do this stuff if necessary but it will be a major problem as I don't exactly have all the tools and an engine hoist at my command. I know this much if the intermediate housing comes off I will change the shift rod too.
I read some of the other threads about overheating and fixing the problems. I'm having similar issues with my outboard. I just had the lower unit serviced, I had drained half a quart of milk water from it. The shop resealed it and put in a new impeller kit. Prior to that I tried to run the motor and it overheated. I saw the impeller was shot so I figured that was the problem. Now I still have overheating issues so I'm trying to figure out where to go first before I start taking water jacket covers off and possibly snap old rusty bolts. When I put the lower unit back on I also put two new thermostats in. Something else to note is I use the rabbit ears where water splits to both sides. I also have the smaller pair where the water comes out one side and the other is just a muff to block the other intake. The hose from the house seems to put out plenty of water when I wash my boat and stuff but I figured I'd throw that out there. I'm half wondering if my rabbit ears could be a source of bad water flow too. When I turn on the water full blast it seems to come pouring out the sides of the ear muffs. When running I can't tell where water should come out with exhaust but it seems to exit the hub in the middle of the prop.
I'm seeing this motor has a pressure relief spring at the bottom of the exhaust cover between the two cylinder banks. My questions are:
1.) How likely is this part to fail and how often is it usually serviced/replaced? The thing looks pretty flimsy in the manual but no instructions are stated for maintenance.
2.) I'm assuming and hoping that some larger particles that may have broken off the impeller would possibly get trapped there and cause a poor flow of water.
Before the lower unit servicing, no water came out of the telltale and cylinder temps shot up to almost 200? quickly. This time some water came out of the telltale although it was without pressure and when I took the hose off it, water kind of dribbled out of the hose. The temp on the thermostat cover was about 15? lower than the temp on the head cover. Both port and starboard banks overheated at the same rate. On both banks the lowest cylinders (#5 & #6) seemed to run cooler than the ones above them at first then caught up when temps got above 175?.
I'm definitely going to look at that pressure relief spring tomorrow morning. After that I need cylinder head cover gaskets and those come off for a cleaning. Probably the heads themselves also.
Suggestions on where to start please. As I said if I can avoid having to remove the covers and such I would like to. Also when I took the lower unit off to bring to the shop I removed the impeller. It did not appear to be missing any pieces. The vanes were cracked themselves yes and the outside edges started to flatten out but it seemed intact. Also the mechanic told me that the lower unit itself is basically an empty cavity that fills with water thru the intakes. He said there did not seem to be any blockage or anything wrong down there so I'm thinking my problem lies someplace between the impeller (possibly a faulty install) and the new thermostats I installed. Could both banks have totally clogged water passages?
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