I put this out on the forum a few mos back, and got some tremendous help, thanks, gents. Last fall I replaced the water pump ( which was actually still in great shape ), replaced the thermostats and poppet valve. This past weekend I put her in the water, and fired her up, tied to the dock. The water pump got no assistance from running through the water and have water forced up to the top of the engine. It ran for 40 minutes and NO sign of overheating, no overheating alarms. QUESTION: If the engine ran for 40 minutes in 42 degree water, and there was no alarm, is 40 minutes of run time long to enough to believe that my overheating problems are resolved? Thanks in advance. Hot Ajax
Yamaha V-6 225 Salt Water Series II, 1997 - Overheat Alarm
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Re: Yamaha V-6 225 Salt Water Series II, 1997 - Overheat Ala
It might be. But you may not fully know till you get it out and give it a good, extended run (loading the engine up). The 42* "could" be helping to mask things - but it's hard to say. A good, WOT run for about 10 minutes should prove things.
Did it overheat, previously, while at idle?
It might be. But you may not fully know till you get it out and give it a good, extended run (loading the engine up). The 42* "could" be helping to mask things - but it's hard to say. A good, WOT run for about 10 minutes should prove things.
Did it overheat, previously, while at idle?
Re: Yamaha V-6 225 Salt Water Series II, 1997 - Overheat Ala
Yes, it overheated on idle after about 10 mins of run time while it was dockside. That was in 60 degree water. But a really good pisser now.
Yes, it overheated on idle after about 10 mins of run time while it was dockside. That was in 60 degree water. But a really good pisser now.
Re: Yamaha V-6 225 Salt Water Series II, 1997 - Overheat Ala
If it's under similar conditions, then that lends more credence to it being fixed. You'll know for SURE once you run it, but it sounds positive.
Just as an FYI, while the pisser is an "indicator" that water is flowing towards the engine, it doesn't necessarily tell us everything. For example, the pisser could be clogged, yet there could still be plenty of water getting to the engine. On the other hand, the engine side of things could be clogged yet the pisser could be flowing like a race horse.
If it's under similar conditions, then that lends more credence to it being fixed. You'll know for SURE once you run it, but it sounds positive.
Just as an FYI, while the pisser is an "indicator" that water is flowing towards the engine, it doesn't necessarily tell us everything. For example, the pisser could be clogged, yet there could still be plenty of water getting to the engine. On the other hand, the engine side of things could be clogged yet the pisser could be flowing like a race horse.
Re: Yamaha V-6 225 Salt Water Series II, 1997 - Overheat Ala
Well that was the situation in the fall ( before I replaced the t-stats and poppet valve ). I had a pisser, somewhat wimpy, with the mouse ears. The garden hose had enough force to push the water up the tube and make it look like everything was fine. But then I threw her in the water and that's when I noticed the problem with the alarm. Since then, I replaced the t-stats and poppet valve, and this past Sunday was the acid test for me when I took her dockside and ran her in the water with not a peep out of her. At this point, I still don't know for sure if the problem was with the t-stats ( which actually looked pretty good and not at all corroded ) or the poppet valve ( which looked really cruddy ). But to an engine running at 200 degrees, I don't think there's a hell of a lot of difference between 60 degree water and 42 degree water. The water pump was fine, in fact the impeller looked like it belongs in the the display windows at Macy's. I appreciate your responses.
Well that was the situation in the fall ( before I replaced the t-stats and poppet valve ). I had a pisser, somewhat wimpy, with the mouse ears. The garden hose had enough force to push the water up the tube and make it look like everything was fine. But then I threw her in the water and that's when I noticed the problem with the alarm. Since then, I replaced the t-stats and poppet valve, and this past Sunday was the acid test for me when I took her dockside and ran her in the water with not a peep out of her. At this point, I still don't know for sure if the problem was with the t-stats ( which actually looked pretty good and not at all corroded ) or the poppet valve ( which looked really cruddy ). But to an engine running at 200 degrees, I don't think there's a hell of a lot of difference between 60 degree water and 42 degree water. The water pump was fine, in fact the impeller looked like it belongs in the the display windows at Macy's. I appreciate your responses.
Re: Yamaha V-6 225 Salt Water Series II, 1997 - Overheat Ala
I had popet vavle issues with my boat. I replaced it with the new style. From what I understand is that the oring in the block gets buildup under it and then the plastic valve cannot close completely. The new style helps prevent this. A stuck open popet could result in a poor stream, but not always I believe
I had popet vavle issues with my boat. I replaced it with the new style. From what I understand is that the oring in the block gets buildup under it and then the plastic valve cannot close completely. The new style helps prevent this. A stuck open popet could result in a poor stream, but not always I believe
Re: Yamaha V-6 225 Salt Water Series II, 1997 - Overheat Ala
A inexpensive fix for this water pressure guessing game is to install a water pressure gauge. Shows pressure through the water jackets in the block,. Remove one of the engine block plugs install a fitting with a small hose up to the gauge at the helm. Shows pressure from idle through WOT. Would not be without it on my Yam F200xb. The Yam gauges show oil, temp and voltage but the separate water pressure gauge is cheap and easy to install. I believe that Yam has a add on to the system in the newer outboards to show water pressure but no doubt it is expensive knowing the Yam prices. Yes my 2 bits. Cheers, trapper
A inexpensive fix for this water pressure guessing game is to install a water pressure gauge. Shows pressure through the water jackets in the block,. Remove one of the engine block plugs install a fitting with a small hose up to the gauge at the helm. Shows pressure from idle through WOT. Would not be without it on my Yam F200xb. The Yam gauges show oil, temp and voltage but the separate water pressure gauge is cheap and easy to install. I believe that Yam has a add on to the system in the newer outboards to show water pressure but no doubt it is expensive knowing the Yam prices. Yes my 2 bits. Cheers, trapper
Quick question since this what I am working on—— same gauge system——- will gauge operate during fresh water rinse thru the hose adapter, my port from engine has water coming from it (hose removed) but hose to gauge, water doesn’t flow from gauge end but with a light vacuum water will flow , going out on 2nd sea trial once I know it’s safe. Maybe it’s just a water volume thing with the wash down hose
If the cooling water is cold as yours was at 42 degrees, you can't be sure if your cooling system is up to par. In addition, running on muffs often can produce higher water pressures than your pump can. Running in the water or in a drum is a better test. Secondly, if your water pressure from the hose and muffs is higher than what your pump can produce, the motor will see the higher water flow and that can hide a weak pump condition.
A stuck open or partially open poppet can cause over heating at low revs but again if the water source is very cold, you may not have that condition.
200 degrees seems too warm to me.
If you had a thermostat issue, it is less likely that both would go bad at the same time. In theses cases, a hand held infrared thermometer is the tool to use to see if one head is hotter than the other. You can also get an idea just by starting a cold motor and with the cowling off, feel the t-stat housing with your hand every minute or so. If one head has a cooling issue, you will notice the difference. Note that although you can feel the difference, you can't easily tell if one side is too hot or one the other side is too cold ( as in the case of a stuck open t-stat. The thermometer is a better test)
A stuck open or partially open poppet can cause over heating at low revs but again if the water source is very cold, you may not have that condition.
200 degrees seems too warm to me.
If you had a thermostat issue, it is less likely that both would go bad at the same time. In theses cases, a hand held infrared thermometer is the tool to use to see if one head is hotter than the other. You can also get an idea just by starting a cold motor and with the cowling off, feel the t-stat housing with your hand every minute or so. If one head has a cooling issue, you will notice the difference. Note that although you can feel the difference, you can't easily tell if one side is too hot or one the other side is too cold ( as in the case of a stuck open t-stat. The thermometer is a better test)