older 350 MPI FWC Mercruiser v-drive on 1989 290 Luhrs.
So when we fired the motor up today it died after 10 sec. of running ruff… first start in a week… made 150 mile trip last weekend.
Motor would not turn over after it died. When we pulled the plugs the Port side was filled with water. Boat has been sitting in a slip, so not from backing to hard on a fish.
Has a big silencer (exhaust) tank that would catch any water coming in from the side exhaust outlets.
I think we got all of the water out of the cyliners, but letting in air dry over night. The motor cranks easy now that the plugs are out, with no clin, clank, bang, or slap. So i don’t think anything internal is broke.
I pulled the riser off and put a hose in the input for the cooling water. Water only came out of the 3 slots that it should come out of.
What should i check next? Get water preassure test the riser?
Thanks as always for the help
1986 17’ Bayliner Capri
150 hp Force
Risers are probably shot given the water injection holes for the exhaust are clogged up with corrosion.
No matter how well a riser might be made, if it is not self draining it will eventually fail. Cast iron risers on I/Os are a maintenance item. Go ahead and plan to replace them all.
Iain Pelto
Edgewater 185CC “Jumpin’ Bean II”
Native Manta Ray 14
new set of risers and manifolds
risers were pretty bad. They are only 2 years old… 140 hours on motors.
We will see what happens when i take them to the boat Dr.
Thanks
1986 17’ Bayliner Capri
150 hp Force
thats unusual for the risers to only last two years, even with out flushing they generally last at least three years. How did the gasket surfaces look? Both the riser and manifold? Did the motor happen to “kick back”(run backwards) whie you were trying to fire it? When you put it back togerther, make sure you use the grey, metallic Mercruiser riser gaskets, they are the only ones to use, regardless of which manifolds and risers you use. Get some fogging oil down the cylinders before it sits long, you may end up having to do more repairs if it starts to rust
It did “kick back”. We ordered new risers and manifolds for both engines. Going to check the timing once we get it running to see why it ran backwards.
Thanks
1986 17’ Bayliner Capri
150 hp Force
do a compresion test before you do anything else, cut teh water off to the engine, spin it over good to make sure there is no water in the cylinders then do a compresion test. This should tell you if there is something internal going on, look for any cylinders too high or too low. Depending on the gauge and how fast the engine spins over, they should be in the 150 psi range, if its a later model engine with vortec heads, 185 psi range. If any cylinders are low, go back and do awet compresion test, meaning squirt some oil in the spark plug hole and recheck compresion, if it doesn’t come up any, you have valve problems, if itcomes up a bunch, you have ring problems. Even if its in perfect shape, with oil added, it will come up some.
Is thet what would make is run backwards?
We thought it was not internal, since the water in the cylinders were saltwater not anti-freeze.
Thanks
1986 17’ Bayliner Capri
150 hp Force