Maintenance overview for 1988 MerCruiser 4.3 alpha one

[Classic88]

Hi, I’m new to boat ownership and have recently bought a 1988 17.5 foot bow-rider with a Merc 4.3 alpha one (gen 1). I am doing the bellows, shift cable, trim sensors - along with an alternator change - but wanted advice on what else I should be looking at to get it ready for the first full season on the water. I ran it for a couple of weeks in the autumn, and it runs really well for its age. What are the key things to look at for a new-to-me boat of this vintage? Any advice of key things to check, adjust or change is much appreciated.

 

[QBhoy]

Hardy hardy engines these 4.3. Love them. Other than good marine oil change (around 5 litres), filter and fuel filter...BR6FS plugs and fresh gear oil...they are good to go.
Only real thing to watch out for is the risers and exhaust manifolds. If she has been a sea water boat, get them changed. They’ll let you down at some point.
If you really want her 100%...do the alpha impeller, UJ and gimbal bearing. You’ve got the bellows mentioned earlier.

 

[tpenfield]

:welcome: to iBoats . . .

There is the old saying of . . . if it ain't broke, don't fix it. So, just be prudent on what you repair/replace.

I think you are off to a good start. Make sure you have the proper Mercruiser service manual for the engine and outdrive.

I would add the impeller to your list, as mentioned. Check the gimbal bearing for rough feel and the U-joints. Grease is your friend. Maybe change the outdrive oil.

How is the boat itself? Any areas of concern?

 

[Classic88]

Thanks for the welcome, and thank you both for these great insights. This is so helpful.

When I got it winterized, they found some water in the gear oil, so that has been changed, but I’ve taken he unit in for pressure testing to see what seals need attention. I’ve asked them to do the impeller while they’re at it. Hopefully the situation isn’t too bad there. I took off the cap and inspected the gears, and they looked good, with no corrosion. The bellows were at the end of their life, so maybe they were the culprits there...

I’m grateful for the advice about manifolds and risers. It’s been a freshwater boat all its life, I believe. Any advice on how to inspect those?

You’re right, I do need to get hold of the manuals. Are they available online?

The one other thing I’m looking at is some play in the steering. I’ve concluded it’s not down at the transom end, but is in the steering console at the helm. The wheel just moves a little before engaging the wire, I think. It’s a quicksilver ride guide rotary rack and pinion (yes, it says both on it!). The thing turns smoothly and pretty easily, just has that bit of play. Any advice there?

Thanks for any and all wisdom in the project!

 

[Scott Danforth]

Links in the stickies for manuals and maintenance tips

A 32 year old boat may have structural issues (very high probability)

Regarding the steering, usually some slop is in the cable and helm. Some slop is at the tiller arm and gimbal.