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New to outdrives have some dump questions

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briang0

Regular Contributor
This is my first boat with an out drive. It is a 1983 CC Scorpion with a 305 Chevy and a Alpha 1 out drive. I have had out boards and in boards but never and out drive so please bare with me while I ask some probably dumb questions.

I started it up for the first time this afternoon using earmuff type flushing things on the out drive. I let it run for about 15 minutes and the engine temp got up to about 130.

Dumb question number one. There was a little water coming out of the prop more water coming out of each side of the the top of the out drive about where the axis point is where the bellows is. Is this normal?

Dumb question number two. It seems that is also where most of the exhaust is coming from on both side and a little through the prop is that also normal. I looked at the bellows and it appears to be intact.

I bumped it into gear to make sure that it went into gear and it did but it made a sound similar to that of standard car with a sticky pilot bearing. There was a clunk and the prop spun. I took it out quickly if I put it back in it was quick as long as the prop was moving no noise I didn't want to do this for very long though. I doubt this it normal so Dumb question number 3.

I did replace the gear oil in the lower unit with 80/90 synthetic this year and I'm positive it's full.

Lastly I let the motor run for about 20 minutes and I noticed that the port exhaust riser was noticeably warmer to the touch than the starboard. Also the water coming out of the out drive on the port side was warm than that on starboard. I'm thinking it's a riser or manifold issue. I did replace the thermostat and I notice that the housing was very rust inside would this have any thing to do with that?

Sorry for the novel.

Brian
 
Everything you questioned is normal as long as you can lay you hand on the manifolds for 10-15 seconds it is the nature of the beast. Do you know when the impeller was last replaced? Do it every 3 years and use a merc. branded impeller.
 
Sounds like everything you said is normal, just like the previous reply......And yes, you should replace the outdrive impellor at least every two years (have done by marine mechanic, about $150)...
 
Re: New to outdrives have some dumb questions

I took some temp readings with an IR temp probe after the engine was running for about 15 minutes on the flushing ears. The port riser was about 30 degrees higher than the starboard. The starboard was running at idle about 75 to 80 degrees the port side was running about 105 to 115. I raised the rpms up and of course both side went up in temperature and the port side stayed about 30 degrees higher. Am I looking at a partially clogged riser? I don't know how old the riser are. Other than this everything appears to be in good shape.
 
again...be assured that "as long as you can lay you hand on the manifolds for 10-15 seconds it is the nature of the beast." It sounds like you bought a well maintained boat; a rare find for an 83.
 
briang0 said:
This is my first boat with an out drive. It is a 1983 CC Scorpion with a 305 Chevy and a Alpha 1 out drive. I have had out boards and in boards but never and out drive so please bare with me while I ask some probably dumb questions.

I started it up for the first time this afternoon using earmuff type flushing things on the out drive. I let it run for about 15 minutes and the engine temp got up to about 130.

Dumb question number one. There was a little water coming out of the prop more water coming out of each side of the the top of the out drive about where the axis point is where the bellows is. Is this normal?
Yes, these two ports are the low speed exhaust relief ports.
The majority of the water should exit through the prop hub at higher RPM.

Dumb question number two. It seems that is also where most of the exhaust is coming from on both side and a little through the prop is that also normal. I looked at the bellows and it appears to be intact.
See above.

I bumped it into gear to make sure that it went into gear and it did but it made a sound similar to that of standard car with a sticky pilot bearing. There was a clunk and the prop spun.
The sound that you heard was the Dog Clutch teeth engaging with each other. This is the nature of Dog Clutch engagement.

I took it out quickly if I put it back in it was quick as long as the prop was moving no noise I didn't want to do this for very long though. I doubt this it normal so Dumb question number 3.
Again, this is normal for a dog clutch drive.


Lastly I let the motor run for about 20 minutes and I noticed that the port exhaust riser was noticeably warmer to the touch than the starboard. Also the water coming out of the out drive on the port side was warm than that on starboard. I'm thinking it's a riser or manifold issue.
Many of the V engine exhaust systems will receive what I'd call an "Un-Balanced" amount of cooling water.
Part of this is due to the T-stat housing configuration and resistance of hoses, elbows, fittings, etc.
Once up on plane, these should equal out re; temperature.
(see ** below)

I did replace the thermostat and I notice that the housing was very rust inside would this have any thing to do with that?
It may if rust scale is preventing an equal flow to each exhaust manifold.
Click to expand...
Brian,

** some will restrict the supply to the cooler side in hopes that the warmer side will receive more cooling water. I would not recommend this.
Instead, and since this is a 1983 "new-to-you-boat", I'd pull the exhaust elbows off, and look at the sea water transfer ports.
Rust scale can restrict sea water flow.
It will cost you a set of gaskets only.

These are the transfer ports. Often these can be cleared out with a few small tools; probe, round file, screw driver, etc.
Push a rag into the open exhaust ports, and use a shop vac to pull the debris out of the transfer ports.

(example picture only)



.
 
Re: New to outdrives have some dumb questions

Hi,

I removed the port riser today it came off quite easily. Much easier than I thought it would. Here are some pictures of what I saw and how I put it back together. I just want to make sure I have the right gasket. I used the same gasket that was on there. I did not remove the starboard side. I only removed the port because that was the hotter side. I did not see any clogs or rust build up. Everything looked really clean I shook the riser and nothing came out. I know from my previous boat that different gaskets are used based on the type of cooling so I figure someone will know if this is the right gasket being used. My engine is a 305 mercruiser and it is
raw water cooled. I put it back together but did not start it. I figured if I had to take it apart again it would be easier. When I picked up the gasket at West Marine there was a different type of gasket with 4 slots instead of 2 there but I figure that was for a different type of cooling system. Although since I don't what the previous owner did or didn't do I want to make sure.


exhaust1b.jpgexhaust2b.jpgexhaust3b.jpg
 
Re: New to outdrives have some dumb questions

briang0 said:
Hi,

I removed the port riser today it came off quite easily. Much easier than I thought it would. Here are some pictures of what I saw and how I put it back together. I just want to make sure I have the right gasket. I used the same gasket that was on there. I did not remove the starboard side. I only removed the port because that was the hotter side. I did not see any clogs or rust build up. Everything looked really clean I shook the riser and nothing came out. I know from my previous boat that different gaskets are used based on the type of cooling so I figure someone will know if this is the right gasket being used. My engine is a 305 mercruiser and it is
raw water cooled. I put it back together but did not start it. I figured if I had to take it apart again it would be easier. When I picked up the gasket at West Marine there was a different type of gasket with 4 slots instead of 2 there but I figure that was for a different type of cooling system. Although since I don't what the previous owner did or didn't do I want to make sure.


View attachment 6879View attachment 6881View attachment 6880
Click to expand...


The manifold water passages look in really good shape. It is normal to have an imballanced temp when at lower RPM's on the muffs. As long as the riser is cool enough to hold your hand on, you should be good to go.

The gaskets you have are the correct shape / configuration, 2 large holes on sides and 2 small ones fore and aft, for your installation of raw water cooled. The 4 slotted ones are for the closed cooling systems that pass raw water through the manifold and riser (1/2 cooling system).

I, personally, prefer to use the Mercruiser graphite gaskets, instead of the green paper ones. But that's just me. The graphites are shaped just like the paper ones you have, but are basically a S/S plate w/ the graphite coating on both side. They seal really well until you decide to remove them. Have seen the green ones turn to mush.
 
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