See full version: Motor won; t start when in water but starts fine with muffs
Do you have water circulating through motor? Lower unit stuff is above me. If water is circulating fine after your fix and engine starts fine and engages to forward and reverse with mutts on, my bet is a too lean setting for idle mixture screws and maybe a little rpm increase on the throttle. here
I'm going to go buy a compression tester and test the compression today but just a little information on what happened this past weekend. I took the boat out to the lake on Sunday and got the motor to start after three tries. I took it for a ride for about 10 minutes and then while idling the motor shuts down. I could not get it to start again so I paddle my way back to the landing dock. Each time I tried starting it sounds like it was going to fire but never got it to. Could this be the side effect of low compression? Or does it have anything to do with the carburetor or fuel? Also, does these model suppose to pee? I didn't see any water peeing out from the motor when I was in the lake yesterday? [links]
do you have an owners manual? There is a "under load" section explaining this scenario.
Yes compression could be an issue. Buy a guage (I would never buy a motor every again without running a compression test no matter what the seller says) and do a test yourself. If the readings are all fine, then you can breathe a sigh of relief. I am not sure if the carbs are set up the same way on yours as they are on my 1983 115 hp motor? Clean carbs is an obvious recommendation. Idle mixture setting appears to be too lean and you might need to adjust your throttle a bit to bring up the rpm's.
Re: Motor won't start when in water but starts fine with muffs here
Pee hole's there for 1 reason. to pee. I'd pull LU and inspect impellar for wear or possibly non-existence.
What;s the serial #?
Re: Mercury Outboard no pee hole discharge more
As Chirs says i would drop L.U. and check the impeller it should pee the only motor I seen that dont pee is those little air cool ones.
If I have the ear muffs installed, I would let the motor run for about 45 seconds to a minute, not a drop of water from the pee hole. Then put it back in the container and pees immediately.
If I submerge the lower unit in a large container covering the lower unit up to about 6" below the exhaust, it pees within 2 seconds on the first crank. Second crank, it will pee water instantly. Motor would run over 15 minutes perfectly without any issues. [links]
I tried to run the motor with ear muffs but water will NOT flush through the pee hole. I've tried to clean out all the hose lines with a weed wacker line and still no water. I've replaced the thermostat with a OEM part and added fresh fuel and still no water. I've also inspected the pick-up screen and no visible debris inside or out. [links]
I have a 2007 DF175 with less than 25 hours. I replaced the impeller/water pump with OEM parts. Also performed a 100 hour service and replaced a few other parts just for the heck of it.
I'm not new to boating and have some experience with working on 4 stroke motors but this issue is new to me. I'm wondering if the water pump housing has a crack that I'm not seeing. Not sure what eles it could be. here
I'm used to engines peeing immediately on startup, as my old mariner did.
Is this "normal" for this engine? I don't have a deep enough tank to run it in, as I already read on here that it needs to be filled 3"+ above the cav plate. [links]
I just got a "new" dory, which came with a 1984 DT40. I haven't had it in the water yet, but have tested it with muffs on (double sided output, round) and whilst it run OK, it takes ages to get anything out of the telltale, and when it does, it's more of a drip. [links]
I haven't checked the impeller, as it looks fiddly to put the leg back on, and I'm worried about screwing up.
is it possiple the impeller is turned the wrong way? I was under the impression it will "self correct" as the shaft spins.
Try flushing from the powerhead hose hook up, you may dislodge it. more
I usually have at least 65 PSI up to 80 PSI, 1" line (PVC) going to the dock and of course, the garden hose will tapper down more yet. I have NEVER had an issue with an overheat, not enough water pissing, etc, on my F150. Maybe more water volume making it to the engine.