DIY Tune-up Advice

[murphini]

All:<br /><br />I have an '89 5.0 OMC Cobra (491 hours) and have the Clymer Manual. I can/do change oil in my vehicles. I can check/change my gear lube. I changed impeller on off season. I changed the cannister fuel filter. I had it professionally winterized last fall.<br /><br />I believe I can gap and change spark plugs, but I am clueless when it comes to rotors, distributors, points, timing, compression, etc. This is my 2nd year of ownership and I put 50hrs on the engine last summer--not sure when it was tuned up last. It runs very good. Manual says it's probably time for a tune up.<br /><br />When one buys a "tune up kit", is it as simple as swapping out those parts, or would it be better to let a professional do it?<br /><br />Thanks.

 

[Mahoney]

Re: DIY Tune-up Advice

If you have a timing light and a dwell meter the timing is a piece of cake. New points and condensors(distributor tune up kit) are fairly cheap and easy to do.<br /><br />The main issue most of us have, present company included, is to just start tackling the tuneup without regard to a little planning.<br /><br />Make sure you mark all your plug wires and the position of where the rotor is pointing when you take the cap off. If at all possible do not remove the distributor itself, you most likely will not have too.<br /><br />If it runs very good as you say, I probably would just pick up a dwell meter and a timing light and see where you stand with those per your manual.<br /><br />I would probably not worry about replacing the points and such if it is running well. Just maybe pop the top off and take a look and see that everything is dry and clean in there.<br /><br />If it aint broke dont fix it. Make sure you keep all old points and condensor when you do decide to do a tune up, it can be a life saver on the water if you run into trouble.

 

[olbuddyjack]

Re: DIY Tune-up Advice

Its good to have an understanding of what your trying to do. Check your manual and see if they have a basic tune up section that explains everything. If not try to find a publication that does(basic automotive is similar) and read up a little to see what your getting into.<br />Dwell is the trickyist part. Its not that tough to do, but it can sure mess up performance if you do it wrong.

 

[Bob_VT]

Re: DIY Tune-up Advice

Look under the distributor cap... are there points? or is it electronic? If it's electronic you can just slip on a new cap and rotor.<br /><br />When you change the plugs just make sure they are the same as what is in the motor. <br /><br />bob

 

[murphini]

Re: DIY Tune-up Advice

OK, finished changing the spark plugs this weekend. All I can say is that the body positions/contortions I had to do to get them out and back in could be a new chapter in a yoga book or the kama sutra.<br /><br />I had to buy a 5/8 sparkplug socket at Sears ($9.99) that has a universal joint on the top to have clearance to get around the water manifolds. Also had to buy a socket driver that has a swiveling head. Broke 2 sparkplugs on the way out, but figured it out. Gapped 'em and put wd-40 on the threads and put new ones back in, 1 at a time, even though the wires were marked 1-8, didn't want to mess that up.<br /><br />Also changed the fuel filter and changed the oil.<br /><br />Put on the earmuffs, got the water going on the outdrive.<br /><br />Charged the battery, installed it but didn't get anything when I turned the key. Took battery back out, used wire brush to clean the contacts and reinstalled the battery. <br /><br />Turned the key and it started on the first try. Very cool hearing the throaty V8 rumble without the water muffling the sound. Manly.<br /><br />I'm ready for the season.

 

[salty87]

Re: DIY Tune-up Advice

"without the water muffling the sound"<br /><br />the hose was attached and running though, right?

 

[murphini]

Re: DIY Tune-up Advice

I meant that usually I hear the engine while the boat is sitting in the water. This time it was on the trailer so it sounded like I had "captain's call" exhaust. I had the hose running while it was started.

 

[Scaaty]

Re: DIY Tune-up Advice

I would ALWAYS buy TWO of EVERTHING you plan to replace. Way too easy to drop a screw, break a rotor, crack a spark plug.........