Thinking About a Boat

Quick check on the jet is to shine a flashlight in from the front intake, and look in at the impeller from the rear. Look for the gap around the impeller, and any gouges along the impeller path. Once the jet housing gets worn, the ski won't have much get up and go.
 
docmirror said:
Quick check on the jet is to shine a flashlight in from the front intake, and look in at the impeller from the rear. Look for the gap around the impeller, and any gouges along the impeller path. Once the jet housing gets worn, the ski won't have much get up and go.
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Also assuming that Kawi jetpump is like mine, the stainless steel liner for some reason can swell up causing it to contact the impeller. That's what locked my jet pump up.
 
jesse said:
Also assuming that Kawi jetpump is like mine, the stainless steel liner for some reason can swell up causing it to contact the impeller. That's what locked my jet pump up.
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I believe you may have encountered dissimilar metal effect between the SS pump liner and the Al jet housing. In a water situation, you can get corrosion in there fairly easy.
 
docmirror said:
I believe you may have encountered dissimilar metal effect between the SS pump liner and the Al jet housing. In a water situation, you can get corrosion in there fairly easy.
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Yeah, I believe that to be the case, and it sounds like a very common problem. A lot of guys take a dremel to the part where it swelled up and claim success. I bought a reman housing which set me back like $500.
 
jesse said:
Yeah, I believe that to be the case, and it sounds like a very common problem. A lot of guys take a dremel to the part where it swelled up and claim success. I bought a reman housing which set me back like $500.
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Yowch.

Years ago I had a BBC pushing an old Panther jet. There was no wear ring in the Panther around the impeller. After a few years at the lower CO river, the thing was getting doggy. I pulled the pump out, and had the housing machined for my own wear ring. I then machined a hub out of tempered Al, and we pressed it into the housing. I made it an interference fit, and then went back with the impeller installed, and shaved a few bits here and there. I also polished up the intake, and intake grate while it was on the bench.

After getting it back in the boat, I changed the cam and carb and that thing would put you back in your seat. That is the boat I never should have sold. 23' Sleekcraft hull, headers, 60 gal tanks, and bimini with enclosure. I loved that boat, but someone paid me $6000 over what I put in it, so it had to go.
 
Ok. It's in good cosmetic shape, both the ski and trailer. He has the title, manual, and receipts. I hooked it up to a battery and it cranks fine. The electrical box was in disarray so I couldn't test the gauges. I could see the impeller shaft rotating inside the engine compartment and looked in the back and could see the impeller blades and impeller shaft spinning while it cranked.

Trailer is in good shape. There's a painted or patched blemish on the front underside of the hull. Doesn't seem deep, but is about 10 inches long.

Judging by what I saw I think I'll get it.
 
docmirror said:
....., and had the housing machined for my own wear ring. I then machined a hub out of tempered Al, and we pressed it into the housing. I made it an interference fit, and then went back with the impeller installed, and shaved a few bits here and there. I also polished up the intake, and intake grate while it was on the bench.

After getting it back in the boat, I changed the cam and carb and that thing would put you back in your seat. That is the boat I never should have sold. 23' Sleekcraft hull, headers, 60 gal tanks, and bimini with enclosure. I loved that boat, but someone paid me $6000 over what I put in it, so it had to go.
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So... What kind of clearance do you guys give between the impeller and the housing ???:dunno::dunno:..

Kinda like a Detroit Diesel blower. .003 or so ?
 
N801BH said:
So... What kind of clearance do you guys give between the impeller and the housing ???:dunno::dunno:..

Kinda like a Detroit Diesel blower. .003 or so ?
Click to expand...

Well, I don't know about others, but that sounds about right, maybe a bit more. I made the casting interference, and did the shaping by hand with some 220 grit, then 600 and finished with 800. I musta taken that impeller on and off 30 times.
 
asechrest said:
Ok. It's in good cosmetic shape, both the ski and trailer. He has the title, manual, and receipts. I hooked it up to a battery and it cranks fine. The electrical box was in disarray so I couldn't test the gauges. I could see the impeller shaft rotating inside the engine compartment and looked in the back and could see the impeller blades and impeller shaft spinning while it cranked.

Trailer is in good shape. There's a painted or patched blemish on the front underside of the hull. Doesn't seem deep, but is about 10 inches long.

Judging by what I saw I think I'll get it.
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If the engine goes around, and seems like it makes compression, hard to go wrong at that price given he has the titles. Go for it. Start a new thread though. :yes:
 
N801BH said:
So... What kind of clearance do you guys give between the impeller and the housing ???:dunno::dunno:..

Kinda like a Detroit Diesel blower. .003 or so ?
Click to expand...

docmirror said:
Well, I don't know about others, but that sounds about right, maybe a bit more. I made the casting interference, and did the shaping by hand with some 220 grit, then 600 and finished with 800. I musta taken that impeller on and off 30 times.
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My 900 STX is:

Standard Limit: 0.005" - 0.01"
Service Limit: 0.02"
 
asechrest said:
I'd love to get a bit luckier than Jesse did on his. I'd hope the engine isn't completely destroyed so that I'm replacing nearly all of it with SBT parts. But, I'm prepared for that as a possibility and it would at least still fulfill my primary goal.

Given that I may be unable to start or crank this thing when I go look at it, is there anything I can do to, for example, determine if 1+ cylinders are seized? For $500 including the trailer I can't expect or ask for much, but what if any major issues can I spot check when I'm standing there beside it?
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2lb bronze mallet and some nylon drifts and a 50:50 cut of Acetone and Transmission Fluid will get the engine taken apart. You can go to a good auto parts store and buy a deglazing hone for not much. Rings are cheap, fix up a spray bottle of Muratic Acid to clean up big crap easily. Jessie didn't have to buy a new engine, it was just a lot faster to get on the water and likely cheaper than a proper rebuild depending on what all parts were past limits. Jessie wasn't looking for a learning project, Jessie was looking to ride a Jetski. You're looking for a project.
 
jesse said:
Also assuming that Kawi jetpump is like mine, the stainless steel liner for some reason can swell up causing it to contact the impeller. That's what locked my jet pump up.
Click to expand...

It's not the SS liner that swells, it's electrolytic corrosion going on between it and the aluminum housing. It's the housing that swells and pushes the stainless into the impeller.
 
N801BH said:
So... What kind of clearance do you guys give between the impeller and the housing ???:dunno::dunno:..

Kinda like a Detroit Diesel blower. .003 or so ?
Click to expand...

Little bit more, you need about twice that due to the size of sand.
 
Dang, I keep coming back to this black hole of a thread ..

Soooo, what if a south TX boy was thinking about a boat to keep in his barn to trailer around to local lakes and maybe some trips to the jetties in Galveston or Rockport?

Something salt water worthy, but lake worthy and river worthy too if there is such an animal. Something easy to trailer and load. Not too big, but not too small. With a head would be optimum. Any suggestions?
 
txflyer said:
Dang, I keep coming back to this black hole of a thread ..

Soooo, what if a south TX boy was thinking about a boat to keep in his barn to trailer around to local lakes and maybe some trips to the jetties in Galveston or Rockport?

Something salt water worthy, but lake worthy and river worthy too if there is such an animal. Something easy to trailer and load. Not too big, but not too small. With a head would be optimum. Any suggestions?
Click to expand...

Depends on what your main purpose for the boat is. A family boat will have a different layout than a fishing boat. While you can use either to do both, they are optimized differently.
 
txflyer said:
Dang, I keep coming back to this black hole of a thread ..

Soooo, what if a south TX boy was thinking about a boat to keep in his barn to trailer around to local lakes and maybe some trips to the jetties in Galveston or Rockport?

Something salt water worthy, but lake worthy and river worthy too if there is such an animal. Something easy to trailer and load. Not too big, but not too small. With a head would be optimum. Any suggestions?
Click to expand...

A 23' SeaRay cuddy cabin like what I bought seems like it would fit the bill, or you could spend a bit more for one with larger bathroom facilities.
 
Henning said:
Depends on what your main purpose for the boat is. A family boat will have a different layout than a fishing boat. While you can use either to do both, they are optimized differently.
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That, and how much/far offshore out of the bays do you want to go?

For my inland lake, my bowrider with mercruiser I/O is fine. If I was wanting a coastal boat, I'd be looking deep-V with twin outboards.

Just my opinion, though.
 
Alright, so back to my boat for a minute. :D

I'm thinking we'll likely only get another time or two on the water for the year, if that. We may be done. So, it's time for me to start thinking about winterizing the thing.

It seems like the big thing is fogging it and then blowing out the lines and/or running antifreeze through the cooling system. I don't have anything for winterizing right now, so advice would be appreciated.

I also still need to order my new cover.
 
Ted DuPuis said:
Alright, so back to my boat for a minute. :D

I'm thinking we'll likely only get another time or two on the water for the year, if that. We may be done. So, it's time for me to start thinking about winterizing the thing.

It seems like the big thing is fogging it and then blowing out the lines and/or running antifreeze through the cooling system. I don't have anything for winterizing right now, so advice would be appreciated.

I also still need to order my new cover.
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Yeah, if you can't put it in a garage, you want to dry out the engine. Drain it from the petcocks and hoses then plug in a ceramic heater in the engine compartment for a day or two. You can stick the leg in a barrel of AF mix and flush it through the engine, I prefer to just dry them out. Before season you can then do an acid flush and get the dried up scale inside cleaned up. Oh yeah, loosen the cover on your raw water pump.
 
Ted DuPuis said:
It seems like the big thing is fogging it and then blowing out the lines and/or running antifreeze through the cooling system. I don't have anything for winterizing right now, so advice would be appreciated
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I do this:

1.) Add the proper amount of marine Stabil to gas tank.
2.) Top up with fresh pure gas
3.) Take a 15min run around the lake
4.) Back at the dock, use an evacuator (like Mighty Vac) to change engine oil/filter.
5.) Start engine for 30 sec. to pump fresh oil thru the engine, then fog it.
6.) Pull boat to trailer or wash rack
7.) Open all cooling system drains to start draining engine
8.) Drain drive foot oil, replace
9.) Add anti-freeze to engine
10.) Remove battery.

11.) Optional: wash/clean/scrub if you like
 
Bill, do you do anything for changing the fuel filter? Seller said he did that as part of winterizing.
 
Ted DuPuis said:
Bill, do you do anything for changing the fuel filter? Seller said he did that as part of winterizing.
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That, the impeller, and the bellows I do every three seasons, seems to work for me. Oh, add exhaust flappers to that list.
 
Bill covers it nicely. The cooling drains are the crux of it.

For the engine, first take off the lowest hose to the water pump. Also take off one of the top hoses that come from the exh manifolds so you don't air lock when draining. Then, look down at the base of the crankcase, under the exh manifold and just above the oil pan gasket line. Flashlight helps. You are looking in the middle of the casting for a small pipe plug, I think it's 3/8" and may have a square plug in there. One per side. when you remove that plug, you may see water just barely dribble out. That's because the crankcase has sand picked up from the lake water. So, take a small screwdriver, or a piece of coat hanger and poke up into that hole, and jimmy the tool around some to dislodge all that silt. You will see water starting to stream out pretty good then. Same on the other side. If your drains have a petcock, don't trust to just turn the little T handle in. They clog all the time. I remove the petcock and insure I get all the water out manually.

The exhaust jacket has a drain either at the center bottom, or the rear bottom. It may be a petcock you turn, or it may be a pipe plug again. One per side. If you have a power steering pump, look under the left side near the water drain and see if there is a cooling slug in line with the incoming water to cool the power steering. It will have two hyd lines attached to it. If so, remove one end of the water hose leading to the cooler because it's at the low point in the delivery and sometimes the raw water inlet doesn't flow back out of the outdrive. On your last recovery to the trailer, if you have time on the ramp, run the outdrive all the way down, and let it sit for a minute to drain back any water trapped in there. Don't forget to run it up to trailer.
 
Skip the antifreeze thing, there is no way for air to freeze and crack anything. The big thing is to make sure all the water is out, in addition to the above stuff use compressed air to blow out anything you've opened up.

If the boat is staying outside for the winter some folks pull the drive off and keep it in the house.

There is a lot of good winterization stuff on IBOATS.
 
lowtimer said:
Skip the antifreeze thing, there is no way for air to freeze and crack anything. The big thing is to make sure all the water is out.
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Per the Mercruiser manual, yes, if drained properly anti-freeze isn't needed. I'm just paranoid. Maybe this year I'll try no anti-freeze and see how it goes.

(but still paranoid)
 
Should I bother with a set of "muffs" to help blow the water out, or will those not really be useful? Curious.

I'll probably go without antifreeze and just blow it all out, then remove the batteries and bring indoors, and fog the engine, and then decide whether to do the oil now or at the start of the season. It still looks clean and new, so I'm leaning towards waiting for next season.
 
This is the throttle I have. It feels like I'm supposed to push the button in. But then it won't release fully.

IMG_20140921_085955.jpg
 
Ted DuPuis said:
This is the throttle I have. It feels like I'm supposed to push the button in. But then it won't release fully.

View attachment 35775
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That's a much newer remote than your boat. You are correct, the button in the base of the handle must be pushed (left hand) at the same time you hit the release button at the top of the control with your thumb (right hand, button you push to move handle out of neutral when shifting) and sometimes you have to wiggle the handle fwd/rev a little to get it to release. If that does not fix it try unhooking the throttle cable from the carb. If there is to much pressure against the idle stop (cable tension against carb idle stop) usually caused by bumping up the idle without adjusting the cable it can cause this function of the remote to jam up.

You mentioned stalling, if it is stalling when you shift it may be likely that the lower shift cable is going bad. When it starts to develop some "drag" in the cable the extra effort to push/pull the cable will cause the shift interupt switch to be activated to long (shorts out the ignition for split second when working properly to assist in in/out of gear) stalling the motor. Yhis is very common in gen I Alphas.
 
Is there any area of knowledge not well-represented on PoA?
 
Ted DuPuis said:
This is the throttle I have. It feels like I'm supposed to push the button in. But then it won't release fully.

View attachment 35775
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Take it apart, clean and lubricate everything. They need occasional servicing. I lubricate all that stuff with LPS-3 because it has a hard wax film on the surface and doesn't collect every random mote of dust to make things stick and jam.
 
lowtimer said:
That's a much newer remote than your boat. You are correct, the button in the base of the handle must be pushed (left hand) at the same time you hit the release button at the top of the control with your thumb (right hand, button you push to move handle out of neutral when shifting) and sometimes you have to wiggle the handle fwd/rev a little to get it to release. If that does not fix it try unhooking the throttle cable from the carb. If there is to much pressure against the idle stop (cable tension against carb idle stop) usually caused by bumping up the idle without adjusting the cable it can cause this function of the remote to jam up.

You mentioned stalling, if it is stalling when you shift it may be likely that the lower shift cable is going bad. When it starts to develop some "drag" in the cable the extra effort to push/pull the cable will cause the shift interupt switch to be activated to long (shorts out the ignition for split second when working properly to assist in in/out of gear) stalling the motor. Yhis is very common in gen I Alphas.
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That cable (the short one from the interrupt switch to the outdrive) is fairly easy to replace IIRC. You can also confirm that as the cause of your stalling by either misadjusting it so it never actuates or by bypassing it. I think the switch shorts across the distributor points and if that's correct you'd disable it by disconnecting any one wire on the switch from either the switch or from where it goes (engine ground or distributor, or ign coil). If OTOH it removes power from the coil when activated you'd have to short across the switch to disable it.

I'd try whichever was easier first and if the engine won't start then, you've got to do the other option. Once the switch is properly bypassed check to see if you can shift in and out of gear without having the engine die. Shifting out of gear will require more force unless you are also slowing down at the same time or have the outdrive tipped up far enough that the prop isn't biting the water.

Whatever you do, don't leave the switch disabled as this will shortly lead to other problems.

The switch is activated when there's significant force applied to the short cable between switch and outdrive. This is only supposed to happen when shifting from fwd or rev to neutral. The fwd and rev gear clutches in a Mercruiser are "self engaging" and have to be forced apart with considerable pressure if there's any load on the prop (e.g. in the water and providing thrust). As you move the control towards neutral, you're applying force to the shifter and that causes the switch to activate. When the switch activates the engine RPM drops rapidly, eliminating the prop load briefly. Then the shifter in the outdrive has to slip into neutral, relieving the pressure on the shift cable thus releasing the switch. If the short cable to the outdrive has high friction the switch doesn't release quickly enough and the engine dies. Generally, going into gear (assuming either the engine, prop, or both are rotating) doesn't generate enough pressure on the switch to activate it but a really sticky short cable can indeed do that, killing the engine when you shift into fwd or rev, especially if you shift quickly (as you always should).
 
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Boat experts:

I have a 70s vintage fiberglass trihull with a 1977 75hp Johnson outboard that I bought last winter. It's had an issue that is progressively worse every time I take it on the water.

Basically, when you'd first take it onto the water it will start run and idle great. But any efforts to go above about 5mph yields no results. As you advance the throttle it keeps running but sounds incredibly bogged down. Usually after about 5 minutes it's like someone just hit a light switch and it suddenly produces full power and is good until you shut it down and let it cool for more than about 15 minutes at which point the problem comes back.

Now it's to the point that it doesn't run right for about 45 minutes of 5 mph operation. It's a ***** to put back on the trailer when it's doing this because it won't idle.

I was initially thinking it could be a carb issue and was planning on tearing them down but it doesn't feel like any carb issue I've ever had. You can be at full power doing 5 mph with it sounding very bogged down and suddenly bam it goes to full power and you about fall out of the boat.

I'm starting to think I may have an ignition issue that clears up once the engine gets hot. Thoughts?
 
jesse said:
Boat experts:

I have a 70s vintage fiberglass trihull with a 1977 75hp Johnson outboard that I bought last winter. It's had an issue that is progressively worse every time I take it on the water.

Basically, when you'd first take it onto the water it will start run and idle great. But any efforts to go above about 5mph yields no results. As you advance the throttle it keeps running but sounds incredibly bogged down. Usually after about 5 minutes it's like someone just hit a light switch and it suddenly produces full power and is good until you shut it down and let it cool for more than about 15 minutes at which point the problem comes back.

Now it's to the point that it doesn't run right for about 45 minutes of 5 mph operation. It's a ***** to put back on the trailer when it's doing this because it won't idle.

I was initially thinking it could be a carb issue and was planning on tearing them down but it doesn't feel like any carb issue I've ever had. You can be at full power doing 5 mph with it sounding very bogged down and suddenly bam it goes to full power and you about fall out of the boat.

I'm starting to think I may have an ignition issue that clears up once the engine gets hot. Thoughts?
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What is your prop pitch? What does the boat weigh, (run the rig across a set of scales, launch the boat and reweigh). First thing I would suspect if you have an issue making power like that is you have a problem with your reed valves.
 
jesse said:
Boat experts:

I have a 70s vintage fiberglass trihull with a 1977 75hp Johnson outboard that I bought last winter. It's had an issue that is progressively worse every time I take it on the water.

Basically, when you'd first take it onto the water it will start run and idle great. But any efforts to go above about 5mph yields no results. As you advance the throttle it keeps running but sounds incredibly bogged down. Usually after about 5 minutes it's like someone just hit a light switch and it suddenly produces full power and is good until you shut it down and let it cool for more than about 15 minutes at which point the problem comes back.

Now it's to the point that it doesn't run right for about 45 minutes of 5 mph operation. It's a ***** to put back on the trailer when it's doing this because it won't idle.

I was initially thinking it could be a carb issue and was planning on tearing them down but it doesn't feel like any carb issue I've ever had. You can be at full power doing 5 mph with it sounding very bogged down and suddenly bam it goes to full power and you about fall out of the boat.

I'm starting to think I may have an ignition issue that clears up once the engine gets hot. Thoughts?
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Simple test to start with would be to take a pair of plastic pliers (fuse pliers from home depot) and remove the spark plug wires one at a time with the engine running in its 5mph max mode. If you pull a wire and nothing changes that cylinder isn't running. Be very aware of the big "meat grinder" mounted on top of that engine when running with the cowling off.
 
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