Merc 170/470

[ryanr623]

Is it only the 4 cylinder, closed cooling 170/470's that need to be avoided?

Im looking at two boats today, one lists a 170 hp engine, in a 1988 wellcraft classic 192 cuddy...... and the other lists 165 hp in a 1979 sea ray SRV190

 

[ezmobee]

Re: Merc 170/470

Yes. It's a 3.7L 4 cyl.

 

[ryanr623]

Re: Merc 170/470

Yes. It's a 3.7L 4 cyl.

Do you happen to know the years it was made? And it only came in 170 horsepower correct?

 

[Don S]

Re: Merc 170/470

Is it only the 4 cylinder, closed cooling 170/470's that need to be avoided?

Personally, I would avoid them, just because of the expensive parts. When working, they are good engines. If you like working on engines and know your way around them and can change head gaskets when needed, you may be very happy with a 470. If you aren't mechanically inclined, forget it.

The 79 165 is an inline 6. Great engine.

 

[Don S]

Re: Merc 170/470

Do you happen to know the years it was made? And it only came in 170 horsepower correct?

The 470 had many different model numbers, including 165. The Aluminum blocked engine with Ford 460 head was built from 78 to 89. With HP ratings from 160 through 190.

 

[ryanr623]

Re: Merc 170/470

The 470 had many different model numbers, including 165. The Aluminum blocked engine with Ford 460 head was built from 78 to 89. With HP ratings from 160 through 190.

Yeah i am not looking to change a bunch of head gaskets. Outta curiousity, were the closed cooling systems the problems on these? Or is it because it put out so much power for a 4 cylinder?

 

[Don S]

Re: Merc 170/470

The early 470's had a 3" diameter heat exchanger which was too small for the engine. They changed to a 4" exchanger later on (not sure which year) and the problem was cured. The 4" kit is still available from Merc for around a 1000 bucks.

 

[ryanr623]

Re: Merc 170/470

The early 470's had a 3" diameter heat exchanger which was too small for the engine. They changed to a 4" exchanger later on (not sure which year) and the problem was cured. The 4" kit is still available from Merc for around a 1000 bucks.

Id just as soon avoid the closed cooling on this engine alotgether. Thanks for the help!

 

[Don S]

Re: Merc 170/470

The 470's are all closed cooled. They never made one that was raw water cooled. The salt water would make short work of an aluminum block.

 

[HT32BSX115]

Re: Merc 170/470

Id just as soon avoid the closed cooling on this engine alotgether. Thanks for the help!

Don't completely discount all closed cooled engines though.....

There's definitely advantages to them in general!

Engines/manifolds last a LOT longer and winterization is a little simpler...


Cheers,


Rick

 

[NetMatrix]

Re: Merc 170/470

Yeah the 470 is definitely a pain in the rear. I have a '84 470 that I was going to completely rebuild for one of my boats since I have some good engine knowledge and my friend knows a lot about marine motors. After I started to price the parts for the motor I discovered that it would be cheaper to just buy a new motor all together. The 470 from what I've heard is considered to be extremely powerful in the water, but COSTS A LOT TO FIX!!!

What you do motor wise is up to you, but I have to agree with everyone else on avoiding that motor.