I hav a mercruiser 3.0 how do you tell the different signs of cracked block or bad freeze plugs ?

Question

1985 boat guy wants $ to take out motor. May be worth it if only freeze plug is bad but he says could be cracked block. Water is leaked into bell housing. Water won't pull up to motor we thought it was impeller. He says starter is ruined and he saw water in bell housing...Signed. To sell or fix??

Answer 1

If you are referring to the flywheel housing as the "bell housing", water being present can come from a faulty freeze plug, cracked block, or a faulty drive bellows. It is very easy to diagnose which. With the boat in the water and engine running, if the water leaking out of the flywheel cover is cold, you have a bad bellows, if the water is warm, it is either a freeze plug or cracked block. In my experience, blocks do not usually crack on the rear surface, so it will probably be freeze plug.

This is a relatively easy fix, the engine is removed from the boat, the flywheel is removed and the freeze plug replaced. With a 3 L, the job should take an experienced tech no more than 2.5 hrs, and the cost of parts is around $20

Answer 2

Freeze plug are only there so the block can be cast. Water in the bell housing is usually because there is water in the bilge that has gotten high enough to get into the bell housing by external mean - like the boat has sunk or is sinking or too much rain and the plug not pulled or the bilge pump has killed the battery. Not likely that the block is cracked if this is your evidence. But the engine needs to come out and be rebuilt and the potential for rust removed.

Answer 3

Mercruiser Bell Housing

Answer 4

whilst I in many instances attempt to no longer supply askers a tense time, you particularly should not be asking us this. you are the guy who can easily see the place the water is popping out. Use a mirror in case you should. definite it must be freeze plugs, because of the fact they are on the front, returned and factors of the engine. they are are particularly plugs for the holes interior the casting while the cores are held in place. yet they in many instances are close to the middle and not the right of the engine. even though it may additionally be a head gasket from the outline. does not ought to bring about water in oil or cylinders. it may additionally be a heater hose setting up to the pinnacle, or a temp sensor. fairly lots inpossible for us to assist.

Answer 5

Did you leave the drain plug in and it got full of rain water while on the trailer ? I have seen that happen many times