Do I need to mill the block??

[Bosunsmate]

Heres one off a v4
http://forums.iboats.com/filedata/fetch?id=7134148
If this was my motor i would polish the piston heads with 320 wetted in methylated spirits too

 

[Bosunsmate]

I have the head off on mine at present, im also doing some very light sanding of the cylinder bore, cross hatching pattern, vertical not horizontal to get rid of any glaze. Horizontal sanding is a no no. Also i have to be careful to clean up so no particles get picked up in piston.
Just an idea you might want to look into before reinstalling the head,

 

[boredindaboro]

I plan on flushing everything before I reassemble. Only thing holding me up its the deflector locations

 

[Bosunsmate]

Ive never worked on one of those 88spls but the deflector locations normally have a couple of small ridges cast into the block for the deflector to sit inside of, if you look for them that should give it away. They go the whole way from the outside of the crankcase right in to the end of the water jacket

 

[boredindaboro]

What does the piston sanding do? Also why would you sand the bores? Wouldn't this make them out of round?

 

[Bosunsmate]

What does the piston sanding do? Also why would you sand the bores? Wouldn't this make them out of round?

Gets rid of the carbon coating on the heads that will build and cause problems,
Its a very light sand to de-glaze them, it wont make them out of round,

 

[boredindaboro]

Ok, I thought you were talking about the inside of the cylinders!...

 

[boredindaboro]

Ok, so head with the bad cylinder is done, New water deflectors installed. Compression on that side cold with fog oil in cylinder is 117, 115 on slow speed starter (Battery about shot). Other side is 120,115 so I think it was a success. Will do other head, water deflectors tomorrow. So I now have 2more questions. First, where is the overheat buzzer located, and second what would be best to flush out the minerals inside the cooling system? Also, would any electronics be hurt if I gently pressure washed this whole engine? Thanks

 

[Bosunsmate]

yes thats a success
Overheat buzzer is normally on the side but near the top of the water jacket cover and has a tan wire coming out of it.
You probably could pressure wash the back half, so long as you were sure that none of the components had holes/cracks. The timing/throttle linkage has grease, so does the gear under the flywheel which could run out under pressure

 

[boredindaboro]

Do you have an image of the overheat buzzer? I found a tan wire but no buzzer. Also will a car battery be OK to use on the boat. Not out at night often and no other electrics on board

 

[Bosunsmate]

Do you have an image of the overheat buzzer? I found a tan wire but no buzzer. Also will a car battery be OK to use on the boat. Not out at night often and no other electrics on board

I dont have a photo sorry but you wouldnt see much from one anyhow as the overheat sensor is buried in a factory hole on the rear side of the head. Where did that tan wire you mention go to?
The actual buzzer/horn is in the control box, its not very big but it should let off a little beep as you turn the key on to inform you its working.
Ive a car battery i use on my boat too. Ive hooked up a multimeter to the wiring circuit so i can get a reading on it in case ive being fishing too long and using the bilge pump too much. Practicing starting the motor with a rope so you know you can do it when you really need to is also peace of mind

 

[boredindaboro]

Mine makes a weird noise when I turn the key to on. Just at the initial turn from off to run. On my electrical harness I found a third tan lead with the bullet connector end on it. It's not plugged in to anything. I KNOW I have personally ruin that motor got and never heard a sound.

 

[Bosunsmate]

That weird noise is probably the overheat horn if you mean its coming from the control box up front.
Touch that bullet connector to ground on the engine with the engine on, if the horn sounds then that is your wire for it, you should really do that with a 12v fuse installed inline in case its something else.
Post a photo of the back of the engine if you still cant find the sender or its location in case its empty but you should notice a empty hole in there if it is missing