Alpha 1 clunks going into gear, and general engine questions

[dpsauto]

I have an 89 maxum 2300sc. I may have more than 1 problem going on so here is some background information. I have been an automotive mechanic for years so I understand the basic operating principles, however I am not a marine mechanic. That being said, basically I know enough to be dangerous. I also have a wife and 3 boys, which means I don't have any money. So any help or advice is greatly appreciated. My boat has a 5.0 mercruiser and an alpha1 drive. The engine seems to run ok for the most part. A little underpowered but it s a 5.0. It does not idle well all of the time. I do not know what the idle speed should be, or what and how to set the timing. It looks like someone walked the wires on the distributor cap.
Part 2 of the problem is that when I put it into gear it clunks fairly loud. It runs good and I see no metal in the lube. I just don't want to tear anything up. I did notice that if the drive is up very far or turned hard over one way or the other I get a little clicking noise. I think it is a u joint but not sure. Knowing that one thing effects another, I'm not sure where to start first. My thought is, wires affect timing, timing affects idle,rpm and power, idle and rpm affects shifting, then "clunk"! Am I right?

 

[tazrig]

Re: Alpha 1 clunks going into gear, and general engine questions

:welcome: The clunking sound you're hearing in the alpha drive is normal and expected. They all do it. As far as your other questions here is a link to a bunch of Mercruiser info including factory repair manuals for both your specific motor and drive along with all the tune up specs and fluid recommendations etc. After memorizing all the info you'll know enough to be VERY DANGEROUS :lol:

http://forums.iboats.com/mercruiser...cellaneous-mercruiser-information-329915.html

I think this is included in the above link but if it's not here is a link to a full parts schematic for your engine and drive:

https://webapps.brunswick.com/literature/literatureSearch.do

 

[achris]

Re: Alpha 1 clunks going into gear, and general engine questions

Sounds like you need a couple of manuals...

ENGINE MANUAL (need to confirm this is the right manual by your engine serial number)
DRIVE MANUAL

Download these and save them..

The clunking is, as tazrig said, normal. It means you're doing it right. The clicking could be unis or the gimbal bearing. Next time you have the drive off for service (and winterise) you can check it out....

When posting about Mercruisers, engine and drive serial numbers are good bits of information to include in the first few lines of the post (or in your signature, like I have)... Everything on Mercruisers is related to those serial numbers, parts look-up, service manual information, etc...

Below are a few videos I put together that might help you....

Links to videos

Removing drive

Checking alignment

Installing drive

Shift cable adjustment

Alpha One water pump service

Cheers,

Chris........

 

[dpsauto]

Re: Alpha 1 clunks going into gear, and general engine questions

Thank you both for the resources and advice. I'm going to find those numbers and start sorting through the information. Like I said, I know automotive but not a lot about marine, I was really worried about the clunk. It seemed a little excessive, but I think it is because the idle speed is to high. I was going to start with the distributor and make sure it is right then move up to the carb. I have couple more questions if you don't mind. 1st. What are your thoughts on changing to an HEI style distributor like the older cars ran and would it make a difference? 2nd. Would I see a significant difference if I changed to a 5.7l motor? And 3rd. I have heard of people putting automotive engines in boats. Is there a big difference or would I just be asking for a bunch of headaches? Again, thank you for everything!

 

[achris]

Re: Alpha 1 clunks going into gear, and general engine questions

To the first question... If the Thunderbolt IV system (which is a HEI system) you have on the engine currently is working, don't change it. Thunderbolt is about the best ignition system you can get. Second question. Changing to a 350 would make quite a difference. It's not just about the horsepower, it's about the torque and the 350 has quite a bit more than the 305.

Now the third question... Putting automotive engines and 'non-marine' parts on a boat engine ... Not a good idea.:faint2: A lot of marine parts are especially prepared to resist corrosion. But the most important reason is that all electrical and fuel system parts are SAE-J1171 marine rated. That means they are designed to reduce the risk of fire and explosion, by reducing external sparking or leaking of fuel vapour.

If you've ever seen the results of a boat explosion, you'd never use another non-marine part again...

Chris.......

 

[Bondo]

Re: Alpha 1 clunks going into gear, and general engine questions

And 3rd. I have heard of people putting automotive engines in boats. Is there a big difference or would I just be asking for a bunch of headaches?

Ayuh,... Welcome Aboard,... While the Marine motors are closely related to their automotive counter parts, there Are diffences in the pieces used in their final assemblies...

Pickup motors are Very Close to marine motors, Hot Rod motors are Distant cousins...

 

[tazrig]

Re: Alpha 1 clunks going into gear, and general engine questions

As achris said only use marine parts. As you'll soon find out anything with the word "marine" on it will cost a lot more but don't start down the slippery slope of asking yourself "how much of a difference could there really be"? While most of the internals of a car engine are similar there are important differences. A car can coast along under power pushing only through the air. A boat never coasts and is always pushing its way through the water. Like constantly driving a car up a steep hill at high speed under full load. So the boat engine needs extra heavy duty parts for some of it's internals. As pointed out earlier anything electrical or fuel related needs to be marine just for safety reasons. Sparks and or fuel leaks never have a good outcome on a boat.

 

[dpsauto]

Re: Alpha 1 clunks going into gear, and general engine questions

I was kind of thinking that's what y'all would say. Had to ask though. I'm a firm believer that the only stupid question is the one you don't ask, right before you mess something up. Your input is important to me and I will gladly accept your advice, use only marine parts. I don't like doing things twice and spending money I don't have. I'll get what I have going good and keep my eyes open for a 5.7 motor. Will the 5.0 accessories and parts fit the 5.7? Or should I look for a complete unit?

 

[achris]

Re: Alpha 1 clunks going into gear, and general engine questions

Will the 5.0 accessories and parts fit the 5.7? Or should I look for a complete unit?

The only difference between the 305 and the 350 (of the same era) is the displacement. Everything bolted onto the 305 will bolt on to the 350.

 

[tazrig]

Re: Alpha 1 clunks going into gear, and general engine questions

^^^+1