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Water pump & impeller

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kirkll

Regular Contributor
Being new to this I/O set up. Pardon me for some really basic questions ahead of time.

I just bought this 1990 Blue Water 19' Cuddy 4.3 230 HP mercruiser, and i'm trying to go through and check things out good before any serious use and breaking things.

I'd like to know where to find the procedure for checking the water pump system correctly. I've heard talk of replacing impellers as a precaution for getting good water flow. is this a complicated process?
 
For a beginner--heck yes! You might want to replace the entire pump system (impeller and housing--sold as a package) if it's damaged.

Jeff
 
kirkll said:
Being new to this I/O set up. Pardon me for some really basic questions ahead of time.

I just bought this 1990 Blue Water 19' Cuddy 4.3 230 HP mercruiser, and i'm trying to go through and check things out good before any serious use and breaking things.

I'd like to know where to find the procedure for checking the water pump system correctly. I've heard talk of replacing impellers as a precaution for getting good water flow. is this a complicated process?
Click to expand...

look on you tube a couple of good videos on how to change it. No sense just checking it, by the time you get in there just replace it.use OEM merc parts vs cheaper aftermarket parts.

if you are fairly decent home mechanic it’s no big deal. No special tools needed, only a lube pump. The first time I did it by the time I pulled the boat, fixed it and was back in the water was about 4 hrs.
 
Dieter said:
look on you tube a couple of good videos on how to change it. No sense just checking it, by the time you get in there just replace it.use OEM merc parts vs cheaper aftermarket parts.

if you are fairly decent home mechanic it’s no big deal. No special tools needed, only a lube pump. The first time I did it by the time I pulled the boat, fixed it and was back in the water was about 4 hrs.
Click to expand...

Thanks Deiter, i did just that last night. I watched a couple you tube videos on it. These guys are saying these should be replaced every two years, and lower unit lube ever 100 hours. what are your thoughts on that?

I’ve done the gear lube maintenance on out boards many times, so that’s no big deal, and pulling the lower unit doesn’t seem difficult.... but it looks like ya need an extra set of hands putting the bolts in after getting the splines lined up.....

kinda reminded me of changing an old 3 speed manual transmission in a 59 Ford years ago, Sometimes they slide right in, sometimes ya gotta wiggle em around a bit.
 
The lower unit lube I change annually or 100 hours if you get that many in a season (I don't). I do that and the engine oil as part of winterization, then yiou are good to go in the spring plus any contamination doesn't sit in there over the winter. Look for milky gear lube (water intrusion) or big chunks of metal. the dog clutch system on an alpha will have some fine metal shavings on the magnet for lower drain plug which is normal.

On the water pump impeller changing time depends on amount of use wand quality of the water you boat in. If you want to be sure every other year is fine but if you boat in northern fresh water lakes like I do and only get 35-45 hours a season I see them lasting 7-10 years and still work fine. My neighbors had 10 years on theirs (150 hrs or so), i'll do mine this fall after 5 years- These are OEM merc impellers.

I did have one fail years ago and what I saw leading up to this was ab out 10-15 degree rise in idle engine temp. I think you will see it creeping up as the impeller ages, so get a handle on what temp you engine normally runs and you can stay ahead of it.

You have the lock it in gear with a bungee cord to line up the splines, much like lining up a clutch disc and pressure plate. Some find it easier to drop the whole drive split it on a bench and drop the upper onto the lower that is in a vise, personal preference IMHO.
 
Wow! You only run your boat 34-45 hours a season? I’ve already logged 130 -140 hours trolling for spring chinook since the first of the year in my open hull fishing boat, and I fish more than that in fall.... but.... I won’t be running my main engine that many hours. I’ll use my trolling motor most of the day, and just use the main motor for running to and from fishing areas.

i still need to go through the whole winterization process.... but my down time , or winter time is short. I fish from February into November most years. So my winter down time is December /January. Fortunately here in Oregon we seldom see seriously low temps for long periods. But some years we have in the past.....

with an open cooling system I would think running anti freeze into it would require using a half barrel with antifreeze in the water. I haven’t got that far yet..... I’ll deal with that part next November-December.

Getting a new to me, older boat, I’m going through one thing at a time right now before I run it too much. There are a bunch of little things that still need attention. I still need to figure out how to change the engine oil in this thing. Lol. This thing is like having a second wife.....
 
kirkll said:
............

with an open cooling system I would think running anti freeze into it would require using a half barrel with antifreeze in the water. I haven’t got that far yet..... I’ll deal with that part next November-December..........
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You are correct.... in order to do that safely, it would require a barrel of antifreeze! :D




Please take a few minutes and read my write-up on the topic of winterizing a Raw Water Cooled Engine using the seawater pump to pull in antifreeze with one of the alleged Winterizing Kits.


https://www.amazon.com/gp/customer-reviews/R3BD7X6QC3KCFR?ref=pf_vv_at_pdctrvw_srp



.
 
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While you are trolling, we're swimming hanging out and drinking beer...

Kind of lucky that I only have to go about 1/2 mile to open water, ski or wake board for an hour or so, hang out and swim for a bit then go back to the house.. and drink more beer.

Typical northern lake bowrider use, basically memorial day to end of September.

You will get almost as many winterization methods as best oil to use ... but IMHO you are way better off just draining it. Depends on the boat but my drain plugs are easy to get to plus you get to see how much water comes out of each drain port and you can probe them if you get silt in the jacket.

The oil spend a few bucks and get a decent vacum pump to suck out of the dipstick tube and if you dont have a remote filter mount up on front of engine its worth it.

Boat is still cheaper than second wife....I spend basically one weekend in spring and one in the fall this includes pulling the lift and both my boat and jet ski.
 
Well with this new boat I can see a bit more summer swimming and playing in. It will be nice to have something we can comfortably put 4 people and two dogs in....

Now I don’t see a lot of fishing happening with a full boat. Especially trolling. Trolling with 4 poles is a pain in the arse. l can see picking up a rope and wake board to drag the kids around on.... maybe one of those big tube-a-rubba’s...

but by fall I want a cooler platform for fish, a wash hose pump set up, and get the other half of my top ordered so I can fish foul weather with out full rain gear all the time and my ears folded back.

im also going to look into how to hook up the trolling motor to the steering some how. There has gotta be linkage that can easily be disconnected or connected. Some days it would be nice to troll from the helm out of the rain..... it’s never ending....

thanks again for the tips and help. Kirk
 
1. Water impeller in drive based on Gen 1 or Gen 2 are different.
Gen 1 can last a few years but take a shape when sitting over the winter and thus require replacement more often.

Gen 2 are more flexable and last much longer.

What drive do you have? Gen 1 has no visable bolts with nuts.
Gen 2 does.

Doing Oil change and outdrive service in the fall in cold weather climates is not the right way to do this.
It is best to do all maintanence and service in the spring.
Especially the outdrive. Seals can fail over the winter.

Winterizing is easy, no need to read that morons story.
He has no Mecruiser experience.

When you get to winterize time. Post and we can tell you exactly what and how to do it the right way that has a proven track record of thousands of boats.....
 
kghost said:
1. Water impeller in drive based on Gen 1 or Gen 2 are different.
Gen 1 can last a few years but take a shape when sitting over the winter and thus require replacement more often.

Gen 2 are more flexable and last much longer.

What drive do you have? Gen 1 has no visable bolts with nuts.
Gen 2 does.

Doing Oil change and outdrive service in the fall in cold weather climates is not the right way to do this.
It is best to do all maintanence and service in the spring.
Especially the outdrive. Seals can fail over the winter.

Winterizing is easy, no need to read that morons story.
He has no Mecruiser experience.

When you get to winterize time. Post and we can tell you exactly what and how to do it the right way that has a proven track record of thousands of boats.....
Click to expand...

im not familiar enough to know what bolts you are referring to to determine whether I have a gen 1 or gen 2. I suppose I could go take photos of it.... where do I find the serial number on the out drive. That might be good way to do it too.

on my out board motors, I’ve always done my oil changes and maintenance in spring, and sometimes a early fall depending on hours logged. Ever 100 hours seems like a lot. I put 200 + hours a year on my fishing boat if work doesn’t get in the way, and typically just do it once a year..... but everyone says 100 hours.... am I screwing up here?
 
When servicing the outdrive, Changing the gear oil alone is not enough. Especially in the fall.

In the spring, The drive must be drained and a pressure check done to assure all seals are integral.

If this is done in the FAll, a seal could fail over the cold winter while sitting in storage and you would never know.

The changing of the engine oil really doesn't matter when as long as it done based on usage.

The image shows the difference between Gen 1 and Gen 2

The image is a Gen 2 see arrow pointing to bolt/nuts

A gen 1 does NOT have these.



0020620_alpha-one-gen-2-sterndrive_550.png
 
Pressure check? First I’ve heard of that one.

How do you go about doing that? and how much pressure should it hold. Kirk
 
kghost said:
When servicing the outdrive, Changing the gear oil alone is not enough. Especially in the fall.

In the spring, The drive must be drained and a pressure check done to assure all seals are integral.

If this is done in the FAll, a seal could fail over the cold winter while sitting in storage and you would never know.

The changing of the engine oil really doesn't matter when as long as it done based on usage.

The image shows the difference between Gen 1 and Gen 2

The image is a Gen 2 see arrow pointing to bolt/nuts

A gen 1 does NOT have these.



View attachment 23820
Click to expand...
Ok.... according to this dwg, I’ve got a gen 1 outdrive..... no side bolts
 
kirkll said:
Pressure check? First I’ve heard of that one.

How do you go about doing that? and how much pressure should it hold. Kirk
Click to expand...

Have you tried youtubing that one?

You probably havent heard of that because you are not experienced in mercruiser outdrives.

I have a Stevens professional grade pressure checker.

Google it to see what it looks like.

It is a hand pump with an accurate gage.

I also have the Stevens Vacuum pump also.

My reccomendation is 12-15 psi (NO higher). And should hold steady for 2 minutes. A loss of 1 ish psi over 2 minutes can be seen based on many unrelated factors.
 
kghost said:
It is a PCR engine designed to his specs, ya know the one about the dished pistons.....
It is in one of the recent post....again..

Makes serious HP.....bahahahaha
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hey guys.... I’m no mechanic, Ive got a new boat here, and am still trying to figure out what I have going on.

If my 1990 4.3 has a different HP, please correct me...... But laughing at my lack of knowledge on a forum seeking help is kind of rude don’t you think?

This motor in my boat was recently replaced with a stock rebuilt 4.3 . Where do I find a serial number, or how do I identify exactly what I have? Btw.... purrs like a kitten so far.
 
.......
kghost said:
It is a PCR engine designed to his specs, ya know the one about the dished pistons.....
It is in one of the recent post....again..

Makes serious HP.....bahahahaha
If you knew more about the SBC, you'd know that the Q/E build creates torque, not horse power.
Click to expand...

kirkll said:
hey guys.... I’m no mechanic, Ive got a new boat here, and am still trying to figure out what I have going on.

But laughing at my lack of knowledge on a forum seeking help is kind of rude don’t you think?
Yes it is rude.
We have two members here who enjoy being rude and childish, and I don't quite understand why MarineEngine dot com puts up with it!
Click to expand...
 
kirkll said:
hey guys.... I’m no mechanic, Ive got a new boat here, and am still trying to figure out what I have going on.

If my 1990 4.3 has a different HP, please correct me...... But laughing at my lack of knowledge on a forum seeking help is kind of rude don’t you think?

This motor in my boat was recently replaced with a stock rebuilt 4.3 . Where do I find a serial number, or how do I identify exactly what I have? Btw.... purrs like a kitten so far.
Click to expand...

He's not making fun of you..you were unwittingly caught in a longstanding debate.

In 1990 - 4.3 2 bbl carb = 175 hp; 4 bbl would be 205 hp

If they by chance replaced it with a newer vortec engine it would be 190 hp/220 hp

Glad it runs well and you now have a new impeller to keep it cool. Make sure to break it in properly , hopefully they provided break in instructions, definitely change your oil after 10 hrs of running
 
Well I have spent the last 50 years of my life pursuing construction related trade craft. Not mechanics.... I spent a few years building boats, Build fine furniture, and the last 10 years got into building traditional bows where I deal with laminating wood , fiberglass, and carbon fiber composite materials to create high performance bows. I deal in thousandths of an inch precision tolerances, and performance is measured in the form of arrow speed and kinetic energy.... yup... it’s rocket science.

if you’d like to see what I’m really good at check it out.... http://bigfootbows.com/b/bows/ I promise I won’t make fun if you if you don’t know what a DFC chart is.

back to boats..... I’m just looking for some help in a field of unknowns here guys. Buying an older boat , I.m going to have to start wrenching more to keep this thing going. I appreciate any help you can give me. Thanks, Kirk
 
..........
Doing Oil change and outdrive service in the fall in cold weather climates is not the right way to do this.
It is best to do all maintanence and service in the spring.


I disagree completely.

Engine oil can become contaminated with combustion by-products that can be acidic and alkaline contaminated.
Change oil/filter at lay-up time, run engine up to temp, then put her to sleep.
If so inclined, you can also "Fog" the engine (if carbureted) to ensure additional protection.

A stern drive left with water contamination can damage gears/bearings when it separates.
Do it at lay-up time, and you'll know the condition.

During winter lay-up, you can add fuel stabilizers to help protect the fuel system for the duration.
Click to expand...
 
Well considering I don’t have much of a winter lay up time, and the recommended hours for oil change is 100 hours, I’ll probably be doing this twice a year anyway.
 
RicardoMarine said:
..........
Click to expand...

That post is all OLD very OLD myth.

Engines can easily sit for months if not years with used engine oil...

Stick with your Model A and B experience....you and your responses belong back then....


Again when its time to winterize, post a new post asking for the correct method and additional steps needed to do it correctly.

Some of us especially the "two" mentioned in an earlier post.
Understand how to do mercruiser as well as many others here.
Unfortunately PCR does not.....sad to say...but accurate
 
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kirkll said:
hey guys.... I’m no mechanic, Ive got a new boat here, and am still trying to figure out what I have going on.

If my 1990 4.3 has a different HP, please correct me...... But laughing at my lack of knowledge on a forum seeking help is kind of rude don’t you think?

This motor in my boat was recently replaced with a stock rebuilt 4.3 . Where do I find a serial number, or how do I identify exactly what I have? Btw.... purrs like a kitten so far.
Click to expand...

I was just pointing out the error. Only 4.3 MPI is 220 hp...
 
Dieter said:
He's not making fun of you..you were unwittingly caught in a longstanding debate.

In 1990 - 4.3 2 bbl carb = 175 hp; 4 bbl would be 205 hp

If they by chance replaced it with a newer vortec engine it would be 190 hp/220 hp

Glad it runs well and you now have a new impeller to keep it cool. Make sure to break it in properly , hopefully they provided break in instructions, definitely change your oil after 10 hrs of running
Click to expand...

No worries.... i got pretty thick bark, and am no rookie to being active on forums. I just gotta figure out who's blowing smoke, and who is not.... Most of my forum activity has been archery related though. I typically avoid mechanics work like the black plague .... Then i go and buy an old boat? Oh well ...... Into the mud again! Its not like i don't have the tools for it.

I think i'll just stick with a 4.3 V-6 as a description. With your description, i'm loosing horse power by the minute. btw... she's got a 4 barrel carb and is a stock 1990 motor.... or so i've been told.
 
Here's the thing. Boat engines are not to be confused with automotive engines. They look a lot alike but have very different performance aspects. A boat engine is like an industrial power plant...it is under constant load and rpm for hours and hours. They never "coast" or get a chance to "cool off". A boat makes a boat=shaped hole in the water. The engine has to push that weight of water around, so it's always going "uphill". On a boat that planes, the engine has to push the boat up out of the hole so that it skims across the surface. The faster you go the harder the engine has to work.

If the engine has been replaced the serial number issue is moot.

There are certain people on this board who believe they have all the answers, never admit they could be wrong and act butt hurt when called out. The one in particular that Ghost is laughing at is someone we call Post Count Rick, or RicardoMarine. He has the dubious distinction of being the single most complained-about poster, according to my highly reliable source, and for good reason.
Beware the quote boxes, blue text and the poached images from his vast stock of gifs and jpegs, these are to make it seems he knows what he's talking about. Don't be fooled.

Chris, Ghost, and several others will always give you solid advice.
 
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