Repair or replace that is the question?

[roykuz]

I have a 1979 22' AMF Crestliner, the interior & hull are in great shape. The engine and outdeive are very questionable. The engine has not been run in 7 years, my son got everything running but a compression was low all around. The engine is a Mercruiser 228 (305 chevy). He would like to replace the engine with a 350 (auto) and change the necessary parts to convert to marime use. He is also thinking of replacing the lower unit and using an alpha drive. I really need som advice and or sugestions. <br /><br />Thanks

 

[SeaRay245]

Re: Repair or replace that is the question?

i have a searay with the 260hp(350) with the alpha one out drive u cant just put a car motor in a boat though boat motors are built for the constant rpm unlike car motors which vary in rpm as for the alpha 1 they usually last a long time if kept up good but they are older and new tech. is the way to go if your goin through that much work maybe a bravo or bravo 3 would be better

 

[G DANE]

Re: Repair or replace that is the question?

Hi Roy<br /><br />Im not a GM specialist, but as far as i remember, it is possible to use block and pistons from a car engine, and take everything else from the marineengine. But i guess with the age your motor has, corroded manifolds could be on the way, if this boat has been run in saltwater. Is this freshwatercooled ??

 

[roykuz]

Re: Repair or replace that is the question?

The engine has never been in salt water. So now I need to know if we install a 350, what trans and lower unit do I need. Anyone have a rough idea of the cost of this project. Thanks for all the help so far. This is one of the most informative boards I have seen on boating ever.<br />Roy

 

[trevorcday]

Re: Repair or replace that is the question?

Make sure that you use all of the correct marine parts or you will have trouble. In my humble opinion it the simplest, least expensive and best likelihood of success will be to rebuild your existing motor using genuine Mercruiser parts. If you do use an automotive engine be sure to install all of the marine fuel system and electrical parts off of your old motor or you could go BOOM. As far as the drive goes a good overhaul should be all that is required. Replace the bellows and Gimbal bearing, check the engine coupler and check the u-joints. Also open up the upper and lower gear cases and inspect the gears. If it hasn'e been run out of oil usually the wors thing that happens is the teeth on the shift clutch and mating teeth on the gears wear out.<br /><br />Unless your unit has an extrodinary number of hours on it a thorough overhaul is probably all you need. Then again you could repower with a complete 5.7MPI...

 

[johnkc]

Re: Repair or replace that is the question?

ROY ,rebuild what you have , it will be easier, faster, less expensive.

 

[ob1jeeper]

Re: Repair or replace that is the question?

Unless you've located a GREAT deal on a replacement MARINE engine of the size you want... REBUILD the one you have... like john says... LOTS cheaper, and if the rebuild is done right, it will give you years of reliable service...

 

[wheels4]

Re: Repair or replace that is the question?

Im sure Ill catch crap for this one but here it gos.I posted a question similar to this a while back.I ended up putting a automotive engine in my boat.I used a marine cam with all the marine electronics and brass freeze out plugs.The automotive block,crank,pistons,rods,push rods,rocker arms.etc. are all the same.You DO NOT have to pay the extra money for something that says marine.If you dont believe me write down your serial#s and go to mortec.com and you will see that they were all used in automotive as well as marine.It was cheaper for me to use the engine I had because my auto.engine did not need any machine work.If your engine is a 72 Im sure it will need to be gone through by a machine shop.Just way your options you dont have to use marine only application parts.

 

[Valv]

Re: Repair or replace that is the question?

I have a Searay 26', and a Bayliner 20'. One with Mercruiser other with Volvo. Both v8 GM. I have rebuilt Volvo keeping same parts, but used auto kit except gaskets and plugs. You can find good kits around $ 300 / $ 350 + shipping and include everything minus crankshaft and block. Used motors can be an option, but just because they bear Marine or Mercruiser name, they are twice as much expensive. As far as outdrive, Alpha is the smaller/weaker one from Mercruiser, a wise choice would be Bravo but they are very expensive. Volvo is better than Mercruiser, as per many suggestions.<br /><br />One thing for sure, check gear ratio from used/rebuilt drive, it has to be a 1.50 to 1, otherwise you'll might tear something right away.<br /><br />Depending from your older drive, you might be able to install Alpha on same gimbal housing, if you use Bravo or Volvo you will have to replace that too.<br /><br />Since you have all the parts there, I suggest like everybody else to rebuild your motor and drive. If you want to add more power, beware the outdrive might not take it, it's kinda put a V8 Chevy on a Geo Metro transmission, it might work, but for how long.<br />Remember out on water, there is no "parking and go get another vehicle" towing is very expensive plus all the consequences due to reload dead boat on trailer, stranded in the middle of nowhere, etc.<br /><br />You don't have to spend a fortune, but sometimes cutting too many corners, it's counterproductive. <br /><br />Val

 

[ICEMAN]

Re: Repair or replace that is the question?

Hi, Another thing you need to watch for is the year of the motor you are going to put into the boat. GM changed the motor design a while back. The newer motor may have a one piece crankshaft seal on the back of the motor. This change, changed the bolt pattern for the flywheel. The old flywheel will not fit the newer motor. You would have to get another flywheel and coupler. Also how much mileage is on the motor you are going to use? The motor will run under different conditions, A short life should be expected.

 

[Walter]

Re: Repair or replace that is the question?

The 195 hp 305 Chev/MerCruiser 1 in my 1980 Beechcraft went south, so I had Gray's Automotive build me a 350 marine engine (Marine gaskets are essential)short block and I swapped out everything else from the 305: "tin", exhaust system, intake manifold & carb, starter (marine starter another essential). A Merc tech buddy of mine helped me revamp the outdrive... Everything went together perfectly and I'm really pleased with the 350's performance.<br /><br />The cheapest route for you would be to rebuild your 305...but I don't recommend it. They are low compression...mid range performance engines. It's not that much more to upgade to a 350...and I think you'll be happy that you did. Your MerCruiser 1 is plenty stout to accomdate the extra horse power...you just need to ensure it's in good order. Replacing the bellows, gimble bearing, u-joints etc...while the engine is out makes a lot of sense and I strongly suggest you consider doing that.<br /><br />To me the bottom line is that if you're otherwise please with this boat and plan to keep it awile, then you outta step up and do it right. It'll be worth it in the long run...trust me!<br /><br />Good luck...<br /><br />Walt