I am having water pressure problems with only 5 psi on one motor that starts to overheat when being pushed, the other motor runs about 15psi and no overheating. Today i changed both sea pumps but no difference in pressure. What controls the pressure apart from the sea pump?
One motor also has a fueling issue, when starting from cold it is overfueling and if it doesnt catch first time it is so rich that i have to open the throttle 50% to lean it off enough to start. The other motor always starts and idles perfectly first time.
Neither motor likes having the throttles opened in neutral they bog down and stall with too much fueling, is this normal?
Check the drives, if I remeber correctly that boat has two different lowers on it and one used to clog up pretty easily with grass. Check the sea strainer as well. We had to flush one of them out a few times when running. You should be able to tell which one, just look in the lid, then check the drive on the same side. I bet you it is clogged up. It happened to us a few times when we went out. The other drives never had any problems ever.
One of the motors also ran alot richer than the other, and was noisier at start up. My friend had to change plugs a few times on that motor. Check the plugs, its probably time for some new ones. The ecu's were mapped by Arizona Speed & Marine. It might be worth sending them back to get em checked out.
Other than those two things, the boat never had any issues and was meticuosly maintained.
Last edited by NOMOGOFAST; 09-15-2008 at 06:53 PM.
Check the drives, if I remeber correctly that boat has two different lowers on it and one used to clog up pretty easily with grass. Check the sea strainer as well. We had to flush one of them out a few times when running. You should be able to tell which one, just look in the lid, then check the drive on the same side. I bet you it is clogged up. It happened to us a few times when we went out. The other drives never had any problems ever.
One of the motors also ran alot richer than the other, and was noisier at start up. My friend had to change plugs a few times on that motor. Check the plugs, its probably time for some new ones. The ecu's were mapped by Arizona Speed & Marine. It might be worth sending them back to get em checked out.
Other than those two things, the boat never had any issues and was meticuosly maintained.
Thanks NOMOGOFAST, i have checked and cleaned the strainers , (there is very little grass/seaweed here in the mediteranean sea), but not the drives.
Yes one motor is richer, but only during the cold start cycle,i discovered yesterday that there is a small tube that has disappeared (probably ingested) from one of the injector bodies on that engine which may have something to do with it, but it would only affect the cylinders that body feeds, (the injector body is no longer available from Mercury but it looks like a Holley pro jection piece does any one know)? but all cylinders
are rich. I will speak to Arizona.
Fred
I am having water pressure problems with only 5 psi on one motor that starts to overheat when being pushed, the other motor runs about 15psi and no overheating. Today i changed both sea pumps but no difference in pressure. What controls the pressure apart from the sea pump?
One motor also has a fueling issue, when starting from cold it is overfueling and if it doesnt catch first time it is so rich that i have to open the throttle 50% to lean it off enough to start. The other motor always starts and idles perfectly first time.
Neither motor likes having the throttles opened in neutral they bog down and stall with too much fueling, is this normal?
Fred
Rich at start-up is classic symptom of leaky injector(s) on that motor that starts hard. Probably not any other issue from what you have described. Fuel pressure leaks off while motor is off, so end up being rich at next start-up, then clears after running if plugs not fouled.
The motors ran rich because there were no thermostats fitted, probably because of the overheating!
Fitted t/s now, running great, but motor overheats faster, i have noticed that the water flow from the exhaust is much less with rpm on the hot motor .
I have been thru everything, new sea pump, waterpump, checked strainer and all i can think now is that water flow into the motor/sea pump is being restricted, so it it possible that the waterpipe connecting the leg to the gimbal plate is collapsing under vaccuum?? Has anyone experienced this??
Fred
If your sure there are no restrictions in any of the coolers or exhaust - I recommend removing the hose nipple from the transom plate and checking to see if the hose has collapsed on the insert. This is not uncommon on salt water boats as corrosion builds up around the outside of the hose then restricts the flow. This is the hose coming from the outdrive to the sea water pump on the inside of the boat. One thing to be careful about are the two 1/4 bolts that hold on the hose nipple - if they are stuck - tap on them with a small hammer and work them loose. IF they don't come loose, be prepared to remove the engine so you can go ahead and break them off and then drill them out - if worth it. Most of them I've ran across that the bolts were stuck and no way no how they were coming loose - the transom was so corroded we replaced it w/ new. I have one now we've been working on when time permits tapping and then moving back and forth. Fortunately once this one is off there is enough access to change the hose and get the insert screwed back in. A Formula I worked on not long ago has the same issue - but there is no way in hell to do the job with the motor in. Also you may try and find a boroscope and look inside the nipple - this was how we confirmed the one I'm working on now.
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