The dreaded 3.7

[greg crosby]

Hi
I just bought an 88 Islander 221 with the 3.7 motor. 22ft Islanders are hard to find here in Maine . When I finally found one it has a 3.7 in it! Much rather have a 140 4.

Well I guess I'm in for an education. The alternator has dealer retro. It does not overheat, has low hours, and has always been authorized service. Just got Mercruiser #8 manual.

What to keep an eye on? Upgrade to electronic ignition? Good synthetic oil? Heat exchanger cleanout every year? Change upper waterpump before trouble? I know there is a ton off stuff in archives but maybe someone has a list?

If I repower 140/gm/4 would be ok? I'll look for donor boat(plenty around) Starcraft forum.

Thank you
greg

 

[Don S]

Re: The dreaded 3.7

Good grief man, work yourself into a panic why don't you.

if your engine has been maintained, it will last as long as the boat will. You don't need synthetic oil, or electronic ignition.
Changing the engine circulation water pump is not necessary. It's the seal and cam that fails, and that does not happen to all of them.
If it does happen, you replace the seal and add a speedy sleeve to the cam to renew the surface.

No a 140 will not be enough power for that size boat.

Keep up with the standard maintenance, a new impeller a year is just insurance. They typically get replaced every other year (as a rule of thumb) on other engines with that drive.

 

[Rake722]

Re: The dreaded 3.7

Hi
I just bought an 88 Islander 221 with the 3.7 motor. 22ft Islanders are hard to find here in Maine . When I finally found one it has a 3.7 in it! Much rather have a 140 4.

Well I guess I'm in for an education. The alternator has dealer retro. It does not overheat, has low hours, and has always been authorized service. Just got Mercruiser #8 manual.

What to keep an eye on? Upgrade to electronic ignition? Good synthetic oil? Heat exchanger cleanout every year? Change upper waterpump before trouble? I know there is a ton off stuff in archives but maybe someone has a list?

If I repower 140/gm/4 would be ok? I'll look for donor boat(plenty around) Starcraft forum.

Thank you
greg

I paniced when I discovered I had a 470 engine in mine.

$60000 and I'm now happy with my 4,3 - lol - only joking.

As Don said, dont worry, if it doesnt overheat and runs well - enjoy it.

I just got a pertronix, not fitted it yet but part of me wonders whether its worth it.

Got a 4 inch heat exchanger, did the water pump entirely.

Had an overheat, found a bad water pickup hose - all good now and loving it. on the plane in seconds with 5 adults in an 18ft draco.

 

[Rake722]

Re: The dreaded 3.7

Oh and one more thing - be nice to the guys at the breezeworks forum - 470 heads.

Nice people with lots of knowledge to share along with iboats.

 

[a1nowell]

Re: The dreaded 3.7

Don't be so afraid of the 470! If it has been maintained as you say you will probably have no problems.

When I bought my tritoon with a 470 in it back in 2008, it had been setting in a cowpasture in Applesprings, Texas for 5 year. Now the upper part of the boat was trash but the engine, after an oil change and some new plugs started right up and ran great. I did the alternator conversion from Breezeworks and put Pertronix' ignition and coil and maintain her pretty well and she starts right up and runs great.

Just my $0.02 worth

Larry

 

[stonyloam]

Re: The dreaded 3.7

++++ to everyone. To check the waterpump seals: 1) make sure the little weep hole on the lower starboard side of the engine pump is clear (toothpick will do). 2) Every now and then check it when it is up to temperature and running to see if any antifreeze is leaking out. 3) don't worry about it until it leaks. Welcome to the 470 club :facepalm:

 

[greg crosby]

Re: The dreaded 3.7

Good tip about waterpump weep hole! This is the kind of info I would like to collect. I will I hope end up with a 3.7 470 Keep an eye on and what to do if list. Where do they get the different hps. for the 3.7 from? Years?

Still like the idea of the chevy 6. If 3.7 gives me too much grief that will be plan B.

Does anyone know where I can get reprints of starcraft owners manuals ?

Thanks guys.

 

[Eric 3.7LX Alpha 1]

Re: The dreaded 3.7

Make sure to have a good accurate temp gauge at the helm. These engines don't respond well to overheating, usually resulting in a new head gasket as the block is aluminum and the head is cast. I have added a Mr. Gasket thermocap to replace the radiator cap on the engine. It gives a mechanical temp gauge to confirm the dash gauge readings.

You'll like the torque and fuel economy of the engine that's for sure!

Welcome to the club! :facepalm:

 

[nola mike]

Re: The dreaded 3.7

...and a repower will be more trouble than it's worth