New to I/O, please advise

4runneradam

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I recently got a 1984 Chris Craft Scorpion 210. Has a Mercruiser 228. Traded it for my last boat, a 85 Bayliner 85hp outboard. Never owned anything but the force outboard, so I'm new to I/O's.

Background on the boat, as I was told by the seller, that an old man owned it, it was a coast guard boat, serviced regularly by the coast guard, winterized in 2005, man fell ill and was unable to use it since then, has been sitting in a barn since then. Was also told deck, seats, and a jasper engine was put in back in 2000.

So, fast forward to today. Oil looks perfectly clean and golden brown color, no moisture on dipstick. Oil filter looks brand new. So I left it in there. I changed the fuel filter. Hooked it up to a fresh can of gas, and fired it up. Found out one of the freeze plugs behind the motor mount must have blown out because it was missing. Replaced that, put muffs on it, and fired it up. Seems to run good for sitting for 8 years. But, there is a tapping noise coming from the starboard side of the engine. Hoping its just a valve tapping, maybe needs adjustment? Not sure how it could get out of adjustment that far. Also, on that same side, the riser I guess its called, sits on top of the exhaust manifold where the water hose comes in, is cold, for the first few minutes, while the other side is much hotter, right away. The body of the manifolds on both sides were the same temp, just the tank part on top was cold on starboard. I let it run for 10-15 minutes, and the starboard side did get much warmer, while the port side was nice and hot (not too hot to the touch). There were also a few small drips at various drain plugs where I need to re-seal with pipe dope.

So heres my questions to the experts. Is the hot/cold on the manifolds an indication of an obstruction in the cooling system? The boat did take on some squirrels, mice, and a snake, as indicated by mice nests, snake skin, and a lot of acorns. I actually vacuumed a bunch of junk out of all the hoses, removed the thermostat housing and vacuumed that, and a bunch of junk came out of the prop (acorns and what not) This leads me to believe I have a blockage. How can I flush this out?

Second question, I don't know how and where the water is supposed to flow throughout the engine and outdrive. Is there a diagram online somewhere that shows how the water flows?

https://drive.google.com/folderview?id=0B56q8a3BkEigSTB4NmZSejVyUG8&usp=sharing

I took pictures and video of the motor running. Maybe you can view the videos and take a guess at what the tapping noise might be? Seems to be coming from the backside of the engine, starboard side. video in the above link shows the noise.

Also, does the water flow coming out the back of the outdrive seem OK? Coming out of all the right places? Theres video and pics of it in action.

Hoping to get the boat on the water in the next few weeks.
 

carribbean soul

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Re: New to I/O, please advise

[video]https://drive.google.com/folderview?id=0B56q8a3BkEigSTB4NmZSejVyUG8&usp=sharing[/video]

18 seconds my 2 guesses are:
1. exhaust leak; look for hot gas coming from the area around #6 & 8 cylinders.
2. collapsed lifter; listen to the engine running with a long screw driver up to your ear to pin point the area of the sound
 

achris

More fish than mountain goat
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Re: New to I/O, please advise

1984 was a bit of a cross-over year for engines and service manuals... One thing that is very important when working on Mercruisers is to have the drive, transom assembly and engine serial numbers handy. Everything to do with parts and information is tied to those numbers. Also bear in mind that the engine is not made by the boat manufacturer, and may be not even fitted by them. The boat, engine, drive and transom assembly could all conceivably be different years (making the year of the boat virtually irrelevant to engine and drive information), so those serial numbers become more important.

That said, for the purpose of helping you get started, here are the manuals for 1984 engines and drives. Please post your serial numbers up and we can check to see if these are the right manuals. If they are, download them and SAVE them, and make backups on a separate computer drive (I use a USB stick). Within the engine manual (section 1A, page 6) is where you'll find the location of the engine serial number. And section 1A, page 2 of the drive manual for the drive serial number (and if the decal is gone or unreadable, the number is stamped into the housing under the decal).

You'll find a water flow diagram for the engine in the cooling system section, that should help you understand the water flow (surprisingly)... As for the different temperatures of the exhaust elbows, completely normal.

One of the things you NEED to do before going anywhere near water with the boat is a full drive service. Remove the drive and do a water pump impeller, oil change, check the drive seal integrity, check all the bellows (you find this information in the drive manual). While the drive's off, check the gimbal bearing and the engine alignment and grease all the grease points. If the engine's popped a core plug, check it very closely for a cracked block, the usual thing that happens to an engine that's not been winterized properly and been left with a block full of water during a freezing winter.

Here are those manuals, and please get back to us with your serial numbers. Maybe put them in a signature file for inclusion on all your iBoats posts, like many of us do (including me)....

ENGINE MANUAL
DRIVE MANUAL

When you're ready to tackle the drive service, let me know, I have some videos that a few people have found helpful and I'll post the links to them for you....

Ar, what the heck, I'll post them now...

Removing drive
Checking alignment
Installing drive
Alpha style water pump service

One last thing. You do not own a 'pre-alpha' drive (as there is no such thing). You may see that terms used quite a lot, by people who are ignorant and don't know any better. A little while ago Bill and I went though the exercise and found there are no less than 33 different drives that were made before the Alpha One drive (1986). With the drive serial number we can determine the correct model of your drive (if it's a 1984, then it will be an 'R' drive). Also have a look in the 'Adults only' section at the top of the forums, there is a plethora of fantastic information to had from there alone.

Chris.........
 

tpenfield

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Re: New to I/O, please advise

A mechanics stethoscope or even a long tube to listen through can help you isolate the noise . . . it sort of sounds like a lifter, but not totally. The exhaust leak theory, already mentioned is a possibility.

As for the temperature on the exhaust 'elbows' . . . often you will find one side warmer than the other. The flow is supposed to be balanced between the port and starboard sides, but sometime one side gets a bit more flow than the other and runs cooler. Definitely get a diagram of the cooling system flow and review it, as it is a bit more tricky than an automotive cooling system.

I am curious about the core plug that was missing . . . was it on the side on the engine towards the rear, or actually at the rear of the engine. Core plugs take a bit of force to come out and we know how that force gets applied (freezing).

For kicks you could run a compression test once it has warmed up for 15 minutes or so . . .

But hey, the boat is a Chris-craft and it looks nice.
 

4runneradam

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Re: New to I/O, please advise

The freeze plug was right behind the motor mount on the starboard side of the engine. When I got it, all the hoses were disconnected, drain plugs removed, as if it was winterized properly. Who knows the real story. I put a new freeze plug in and ran it 15 minutes, and theres no water in the oil.

The engine is supposedly a Jasper replacement from the year 2000. There is no data plate above the starter as the manual suggests, but a decal on the valve cover with a serial number 6674903. I'm guessing thats the original valve cover, but was swapped over with the Jasper long block in 2000. The motor is probably a correct vintage, as it still has all the original accessories.

The outdrive serial number stickers are worn off, so I'll have to remove them to see the numbers stamped in, and report back. But they appear to be the same drive pictured in the service manual.

Thanks for the help guys.

I'll probably pull the valve cover and look for a loose rocker arm or collapsed lifter. I did put my hand all over the valve cover trying to feel for any tapping, and I did not notice any exhaust leak.
 

4runneradam

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Re: New to I/O, please advise

So, i scrapped away the serial number decal on the outdrive, and the number is NOT stamped into the housing. The only number left on the decal was the last 2 digits, 44.

Now what? Any other way to identify?
 

4runneradam

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Re: New to I/O, please advise

I found it. Didn't scrape away enough of the decal. The number is 6659844.
 

achris

More fish than mountain goat
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Re: New to I/O, please advise

According to this site, Outdrive Identification Alpha One its an alpha one / mr.

That's the site that uses the term 'pre-Alpha'... I would love to strangle the idiot who came up with that.... Your drive is an 'R'. Have a look in the 'Adults only' section at the beginning of the forums. In there is a 'History of Mercruiser' article, actually written by the engineers at Mercury. That has all the identification for the different models of drive... The one thing you will NOT find is a 'pre-Alpha'. By definition about 33 drives fit that description, because they were produced 'before Alpha'. Strictly speaking an MR is a pre-Alpha, and as such is grouped with the other 'pre-Alpha' drives, yet it has more in common with the Alpha One than any other drive... So they have shot themselves very much in the foot. (I'd like to shoot them in the face!!!)

BTW, the manuals I posted up are the right ones...

HTH.

Chris...........
 

4runneradam

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Re: New to I/O, please advise

Makes sense. Sounds like they are grouping a whole number of drives made before the alpha one when there are a bunch of different models.

So i have an R drive. Thanks for the info, ill order up some parts once i get the ticking sound fixed in the motor. Im going to pull the valve cover today.


Thanks for the help everyone. Ive got a lot of learning to do!
 

dubs283

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Re: New to I/O, please advise

Strictly speaking an MR is a pre-Alpha, and as such is grouped with the other 'pre-Alpha' drives, yet it has more in common with the Alpha One than any other drive.

in case you were really wondering what mercruiser was thinking in the early-mid 80's...

when mercruiser produced their one mllionth sterndrive package, they renamed the MR drive the "Alpha One and Only" - thus creating the alpha one drive which then became available in a counter-rotated and SS model

aside from the o-ring groove on the lower driveshaft, MR drives and standard rotation alpha one drives are identical

so...

MC-1 = MC-1
R = MC-1 (redesigned)
MR = modified redesigned
Alpha One = well, you get the idea....
 

4runneradam

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Re: New to I/O, please advise

Pulled the valve cover, and found both #6 rocker arms off the pushrods and rotated 45 degrees, and both pushrods bent. Rocker arms and valve springs appear to be ok.

Motor was very clean, and i do believe it was replaced recently by jasper. Had a little surface rust and sludge on the top edge of the rockers from sitting, but zero sludge. I'm thinking maybe the 2 valves are stuck, causing the bent pushrods

I'm going to attempt to free the valves by hitting them with a brass punch, replace the 2 pushrods and reassemble, followed by a compression check. Hopefully theres no piston damage or anything like that. One pushrod had just barely a bend, and the other one had a noticeable bend.

Ive had this happen on some ford 300s and a small block chevy. Ive free'd the valve and replaced pushrods and sent them on their way, so i hope i can do the same here.

I don't thnk timing jumped way off, it seemed to run pretty good, even without #6 firing. I will do a compression check and check timing with a light to make sure. If all checks out I'll run it as is.
 

4runneradam

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Re: New to I/O, please advise

In case anyone is having a similar problem, I did find out what the main "knocking" sound was. Loose flywheel. I took the starter off and grabbed it, moves quite a bit side to side.

Still have the bent pushrod problem, although I did straighten them up and ran it for quite a while, along with the loose flywheel, with no problems. Ran it like this for a few months until i discovered the loose flywheel.

When it gets warm Im going to pull the engine and hopefully just replace the flywheel bolts and loctite them, replace the bellows and gimbal, and either have the head checked and fixed or replace the head(s).
 

Bondo

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Re: New to I/O, please advise

In case anyone is having a similar problem, I did find out what the main "knocking" sound was. Loose flywheel. I took the starter off and grabbed it, moves quite a bit side to side.

Still have the bent pushrod problem, although I did straighten them up and ran it for quite a while, along with the loose flywheel, with no problems. Ran it like this for a few months until i discovered the loose flywheel.

When it gets warm Im going to pull the engine and hopefully just replace the flywheel bolts and loctite them, replace the bellows and gimbal, and either have the head checked and fixed or replace the head(s).

Ayuh,... It's Studs, 'n steel lockin' nuts,... Not bolts,...
No loctite needed either,.... steel lockin' nuts, fine thread,...

You'll probably need a new Coupler to, as it's held by the same studs, 'n nuts...
Bein' an aluminum castin', I'm thinkin' it'll be pretty beat up,...
 

bonzoscott

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Re: New to I/O, please advise

4runneradam - Food for thought: Something caused the push rods to bend, also creating chatter that cut your rocker studs. Likely collapsed lifters. And that may likely be lack of oil. If you're pulling the motor, there's more troubles to diagnose. I worked with a motor that had identical pictures of what you have, however, the cause was rubber valve seal rot and got into the pan and then into the pump. The oil pump locked up, shearing the distributor roll pin, thus it would not run. Seems a prior mechanic cranked it so much trying to diagnose, it drained the lifters making the valve train loose. But since yours was still running with the chatter... Don't know, low on oil or pressure or just a bad lifter... who knows?
 

4runneradam

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Re: New to I/O, please advise

I really dont know what it is either. I cant afford a full rebuild right now, and i have a set of used heads that have been decked that i can throw on.
 
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