1978 Mercruiser 228 Tune Up Questions

[MikDee]

Re: 1978 Mercruiser 228 Tune Up Questions

What you see in the first picture is the u-joint bellows which looks fine as you said, to the right is the shift cable (and bellows), to the left is your main engine water feed from the outdrive water pump impeller, and at the bottom is what appears to be a rubber type cone (instead of another bellows) for the exhaust, meaning someone changed it from thru the prop exhaust, to make a bit more noise, But it's not a problem, and it's all in good shape, a good thing.

By the way, I never bothered with the cables, as they worked okay for me, for as long as I had the boat, so I wouldn't know anything about them.

Also, if you have a 4bbl carb, it is the 228hp motor, the 2bbl carb was a 198hp.

The choke is an automatic butterfly on the carb like a car, but it maybe electrically operated. It is a marine Quadrajet carb.

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

Thanks for all the help.

As the engine warmed up the front butterflys started to open a bit. We didn't run it for very long (total run time was less then 15 minutes, maybe 20) so it probably didn't warm up all the way. Also, the water going to the muffs was from a well, stuff was coming out cold!

Right now my list is as follows;

• Sparkplugs and cables
• Batterybox
• Scupper/blower tubes (still need to figure out where they go)
• Oil Filter
• Oil (have to figure out how to get the old oil out first!)
• Water seperator filter
• Reset the idle. right now I can't put it in neutral, it starves out on me

Hoping to get most of that done on saturday and then take the boat out for a test ride saturday afternoon or sunday afternoon. First run will be in the river (go up river so, if it dies, I can coast back ).

We've talked about disconnecting the throtle linkage to see if it will idle on it's own. Is there a chance that it's the problem and it just needs to be adjusted? I'm thinking if I adjust where the linkage connects to the carb, I can set it up so it'll idle while the lever is in neutral.

The lever itself has a ton of play (put your hand on the lever and, instead of moving it forward, move it left/right, it wiggles). I don't think fixing this will correct the issue but it'll keep it from feeling like it's going to break off on me.

Oh, and the cables I was refering to below were the sparkplug cables. Do I just get a set for a regular 305 or are they a different length? (Need to make sure I ask for the right thing at the parts store.)

And, yes, it is a 4 barrel. So, once I get it running, I'm hopping it'll have a nice pull to it.

 

[Don S]

Re: 1978 Mercruiser 228 Tune Up Questions

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

Said it earlier and I'll say it again, this place rocks.

Thanks much!

 

[PowerAddict]

Re: 1978 Mercruiser 228 Tune Up Questions

I coulnd't agree more, everyone on here is eager and willing to help!

thanks everyone.

 

[MikDee]

Re: 1978 Mercruiser 228 Tune Up Questions

The Picture, Yes just as I said Don,,,

I happen to like the Borg/Warner Mag style spiral core spark plug wires, Yes a standard set for a 305 Chevy will fit, and I recommend plated spark plugs, I like Champion, or NGK's, so they don't rust up on you (had a bad experience with that one time). By the way, usually the only way to change the oil is to get a pump to suck it out of the dipstick hole, welcome to boats. I also use synthetic blend oil, (full synthetic not needed) it holds up better, plus it runs cooler, with less friction, and more power, & economy. You'll probably get a nice mellow rumble in the water with that exhaust cone on there, better then usually another bellows to deal with anyway.

One more thing, with synthetic blend oil, Champion plugs, Borg Warner wires, a rich adjusted 4bbl, a 14X19" prop, a slick unpainted bottom, and thru hull exhausts, my 20' SeaRay did 50mph one time, normally ran 45-48 trimmed out, on the Great South Bay L.I.

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

Thanks for the tips. I'll be heading off to get the plugs, wires, oil, filter and a vampire pump today or tomorrow.

Any advice for getting it to idle in neutral? It doesn't seem to be out of time (ran smooth) but I had to keep the lever forward or it died.

The only fix that comes to mind is the one I mentioned, adjusting the linkage. But I'm worried that it might have just been cold, or something. If it just needed to warm up, and I adjust it, it'll be out of adjustment once it gets warmed up.

Should it, cold, idle in neutral?

 

[Haut Medoc]

Re: 1978 Mercruiser 228 Tune Up Questions

It should stay running after 30 seconds at idle with no help......
Look at your temp gauge, it should go up & then come back down when the thermostat opens.....
The cold well water is irrelevant with respect to how warm the engine gets....
It should get up to temp, (140*) or so......
You can rev the engine up to 1500 rpms without any worries.....
I would not fiddle with the cables yet, because it is highly unlikely that they are a problem....
You said it has been sitting, how old is the gas?.....
If there is not alot, I would drain the tank completely & start with fresh......
Running some Sea foam additive might be a good idea as well to get rid of any varnish deposits in the carb....
Like I said, the fact that it runs at all after sitting is a good sign....
Frankly, at this point, since you say it sounds smooth, I would change the engine oil & the gear lube in the drive, do what you need to do regarding the fuel & put it in the water & just run it for an hour close to shore & see how it does.....
Then do the tune up.....​

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

Sounds like a plan.

I've not heard of Sea Foam, is it a name brand or a nickname for something else?

I'll check the temp guage. Honestly, I was so happy the damn thing was running nice I didn't even pay attention to the guage.

As for fuel, it was pretty much dry. We added in 6 gallons of fresh, primed the carb and then it ran.

 

[MikDee]

Re: 1978 Mercruiser 228 Tune Up Questions

Ok, the normal idle mixture screws setting are 2-2 1/2 turns out from lightly seated to start, it should idle there. Then adjust your idle speed screw, to specs. After awhile once it was running good, I was able to take mine out to 7turns for increased powewr (extra rich).

SeaFoam & DeepCreep, same thing, different form, ones a liquid, ones a spray, get familiar with it,,, It's Great!

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

I'll check the set screws when I do the oil change, thanks.

The Sea Foam and Deep Creep, only available at boat stores?

 

[Haut Medoc]

Re: 1978 Mercruiser 228 Tune Up Questions

Napa might have it.....​

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

Looks like I'll be giving NAPA some money this week.

BTW, 5qts of oil, yes?

 

[Haut Medoc]

Re: 1978 Mercruiser 228 Tune Up Questions

Since you are changing the filter, I would get six, put in five initially & check the level after you run it for a few minutes, in the water......
Then add, if need be......​

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

I like the location of this particular test.

Right now I'm on track to be in OT at work before noon (around 10am actually).

So I should be able to get the work done friday and, if all goes well, spend most of the weekend out on the water (if I have a co-pilot or two brave enough to ride with ).

Oh, any ideas on the blower hoses? I'm going to get some new hoses today but I'm not sure where they're supposed to run. Right now I'm just looking to run the two vent twos close to the engine and then run the one, or two, powered tubes below the floor level near the engine then zip tie them into place.

 

[Pulse121]

Re: 1978 Mercruiser 228 Tune Up Questions

Okay, picked up the oil, filter, deep creep, sea foam, battery box and a pump to get the oil out.

I also think I've found a post that explains where the blower tubes need to go, I'll pick up some new tubes tomorrow on my way over to the boat.

So, oil change, charge the battery, test the alternator, install batt. box and blower tubes, tune the carb, sea foam in the gas, deep creep to start the engine (if needed) for a last test run on the muffs and then head to the water.

I'll update after all of that.