mercruiser 170 info

[bpgood1]

im lookin at buying a 86 sea ray 270 with twin merc. 170 inline 4 cyls. to my knowledge this is a 3.7l 4 cyl with a head from a ford 460c.i. motor. This is kind of a two part question.
1. i've heard some bad things about these engines are there any major red flags to be aware of?
2. the starboard engine has a noise that i believe to be a rod bearing going bad, so in your opinions would it be worth replacing this motor with a rebuilt/reman or is it feesable to repower this boat with 4.3l 6 cyls

thanks in advance for any help guys!!

 

[stonyloam]

Re: mercruiser 170 info

As much as i like my 470 (shotgun marriage) Unless you are capable of, and willing to do all of your own mechanical work (replace head gasket, cam seals) it is best to stay away from the 470. Making the swap to a 4.3 is not practical IMHO.

 

[ssn756]

Re: mercruiser 170 info

I had a 470 and am capable of doing all necessary work but the CONS are over whelming.

Every one here steered me away and I listened. Found a pretty nice boat afterward.

I have 470 parts if you need them but sounds like you need internals.

 

[Don S]

Re: mercruiser 170 info

Here is a resent thread on the same exact type engine.
http://forums.iboats.com/showthread.php?t=465333

 

[Bondo]

Re: mercruiser 170 info

im lookin at buying a 86 sea ray 270 with twin merc. 170 inline 4 cyls. to my knowledge this is a 3.7l 4 cyl with a head from a ford 460c.i. motor. This is kind of a two part question.
1. i've heard some bad things about these engines are there any major red flags to be aware of?
2. the starboard engine has a noise that i believe to be a rod bearing going bad, so in your opinions would it be worth replacing this motor with a rebuilt/reman or is it feesable to repower this boat with 4.3l 6 cyls
thanks in advance for any help guys!!

Ayuh,... With Twins, you won't have enough space between the crankshaft centerlines to fit V-motors...

 

[bpgood1]

Re: mercruiser 170 info

Ayuh,... With Twins, you won't have enough space between the crankshaft centerlines to fit V-motors...

bond-o not to say you are wrong but this boat did come with the twin 4.3's as an option so shouldnt the drive spacing be the same width apart

 

[bpgood1]

Re: mercruiser 170 info

and just an added thought i am a mechanic capable of making any necessary repairs to this boat. having said that i do appreciate the info on this engine setup, and may still consider this boat if the price is right.

 

[stonyloam]

Re: mercruiser 170 info

and just an added thought i am a mechanic capable of making any necessary repairs to this boat. having said that i do appreciate the info on this engine setup, and may still consider this boat if the price is right.

As long as you are going in with your eyes wide open LOL. You will hear a lot of cons, so here are a couple of pros (at least non-cons). If you look at all of the negatives, there are really only two things to worry about mechanically. If you overheat, it is likely that you will blow a head gasket (or it could fail for no apparent reason), and your waterpump cam seals will fail and need to be replaced. Some parts are NLA, true but as far as I can tell most of the NLA parts are things that don't wear out, covers and oil pans and such. Exhaust parts are available, and you can find the other stuff. They are a snap to winterize, drain the heat exchanger on the launch ramp and you are done. They are light and pretty good on gas. Being an 86 the one you are looking at should have 4" exchangers, that is good. Resale is going to be pretty lousy, so take that into consideration. Good luck

 

[telstar1]

Re: mercruiser 170 info

And a seldom mentioned feature the starter is mounted high where it doesnt easily get drowned.