My first V20

[scook]

I have a 170 and had some experience with fixing the internal water pump. Look for any sign of coolant in the bilge - it’s hard to spot where it leaks out if the seal is bad. As I recall there’s a weep hole around behind the pump near the distributor.

Don’t forget to drain the heat exchanger. One winter where you are will destroy it if you don’t - it’s around $1000 from Mercury and mine was around $500 getting it through an online guy who supplies the OEM part direct from the manufacturer. If you end up needing one, let me know and I’ll hook you up.

Welcome to the site - it saved my sanity when I was fixing my water pump.

[Destroyer]

Originally Posted by scook

I have a 170 and had some experience with fixing the internal water pump. Look for any sign of coolant in the bilge - it’s hard to spot where it leaks out if the seal is bad. As I recall there’s a weep hole around behind the pump near the distributor.

Don’t forget to drain the heat exchanger. One winter where you are will destroy it if you don’t - it’s around $1000 from Mercury and mine was around $500 getting it through an online guy who supplies the OEM part direct from the manufacturer. If you end up needing one, let me know and I’ll hook you up.

Welcome to the site - it saved my sanity when I was fixing my water pump.

And remember that draining the outdrive does not mean you drained the engine block.

[Dschaffer]

Thanks again for the replies. I am hoping to get some time this evening to run the motor on the hose. Let's hope it's something simple! The boat runs excellent except for this mysterious coolant leak. I think I'm going to go with the electric trim tabs. My tilt/trim pump oil is mixed with water and has proven difficult to find out where from. I like the idea of fewer hydrolic hoses. I'm hoping to find heated indoor storage for the winter. If that happens, I'll be working on a number of things that I'll be sure to post about on here. Thanks again.

[cfelton]

Years ago I got a Clymer manual off ebay cheap. Its helped me out a lot. If you have to buy any parts shop the internet thoroughly! Ive had good luck getting stuff from Ebasicpower! Also found some good used parts on ebay. I lucked up and found a complete motor that was frozen up from lack of winterizing. Got it cheap and with a little work got it running. If you need anything just ask. I've spent many hours looking for different parts, glad to help. Oh and congrats on the boat, looks great!

[Dschaffer]

Originally Posted by cfelton

Years ago I got a Clymer manual off ebay cheap. Its helped me out a lot. If you have to buy any parts shop the internet thoroughly! Ive had good luck getting stuff from Ebasicpower! Also found some good used parts on ebay. I lucked up and found a complete motor that was frozen up from lack of winterizing. Got it cheap and with a little work got it running. If you need anything just ask. I've spent many hours looking for different parts, glad to help. Oh and congrats on the boat, looks great!

I finally had some time to run the motor on the muffs and was able to find the coolant leak. It appears to be dripping from the front left bottom of the motor, behind the coolant bottle. The picture shows the area. I can feel bolt heads underneath. Could it be as simple as tightening them? I need to get a manual for this engine so I know what I’m looking at. Also, any idea why the bolts next to the plugs are rusting? Any thoughts on this are much appreciated.

[3 Squids]

Perhaps the bolts are in the water jacket themselves. I don’t know much about these motors but know many Chevy motors have multiple boats that must have thread sealant or coolant will leak out. Hopefully it’s as simple as that.

[scook]

You pretty much have the same engine that I have. I’m guessing you have the same problem I had - that the rear seal in the internal water pump is bad. To keep coolant from getting into the engine at the end of the camshaft, there’s a weep hole that lets it drip into the bilge (the water pump is driven by the very front end of the cam.

It’s a pretty big pain to get into it to fix it but if you’re a fair mechanic and a glutton for punishment, you can do it. On mine, the shaft was galled and I had to find a repair sleeve that press fit over the galled section of the shaft. I screwed up the first seal I put in and had to do it all over.

I have manuals but our resident boat mechanic, Spareparts saved me from shooting myself when I was fighting some pesky locating pins that wouldn’t let me get the cover back on. He a very generous guy with his knowledge and will probably chime in when you have problems.

If you find the weep hole and it’s the problem (probably won’t leak until it gets warm enough to build some pressure) and don’t find a manual, I’ll see if I can find the applicable pages and scan & email them to you. I have also had fair luck finding blow up diagrams and even manual sections by Googling around for them, so you should try that first.

Regarding the rusty bolts, I had that problem and it diminished a lot when I fixed the coolant leak so the engine compartment wasn’t so humid. I think the humidity builds up and then condenses when the engine cools off, rusting the bare metal bolts. That’s speculation but it fits pretty well.

It’s a good wintertime project.