Evinrude 175 V6 questions

[sphelps]

Here are some pics of the port side ..




The piston crowns look kinda sooty . Not sure what there supposed to look like ...
There are quite a few frayed /bad looking wires all over . Is there a wiring kit specifically designed for this motor or do you have to go through it one by one replacing the bad wires ...
So , do you think it's safe to go ahead and spend the money on a starter and new gaskets . I would need to replace the torn bypass cover gaskets before another compression test right ?

 

[racerone]

Actually you do NOT have to replace those gaskets or even those covers to do a compression test.----Install a starter and see what readings you get.----Pistons and rings appear to be in fair shape.

 

[sphelps]

Ok , I guess the compression begins after the piston passes the bypass holes .

 

[racerone]

Correct you are.-Actually compression does not start till exhaust ports on the other side close off.

 

[boobie]

Get the compression test done before going any farther on it.

 

[sphelps]

Just ordered starter . Should be here next week ...

 

[emdsapmgr]

Those may be replacement pistons. Not like the originals in my 1979 200. Original pistons from 1978 may have had the top ring right at the top of the piston. Your top ring is set quite a bit below the crown of the piston. All replacement pistons are like the ones you have. Much more durable and forgiving on today's lousy fuels. Pistons look really clean: just a slight shadow of carbon on the piston skirts, but none in the ring grooves! Hopefully, the other 3 are the same. Let us know what your compression readings are with the cranking starter in place.

 

[daselbee]

That's an excellent price on that manual. I would jump on that if I were you.

 

[sphelps]

Those may be replacement pistons. Hopefully, the other 3 are the same..

Funny this may be the case . It kinda looks like the block has been repainted at some point . Hopefully it was gone though somewhat before the po passed away . The starter may have been takin off to be rewound or to put on another motor idk ... All the pistons looked to be in the same condition . The video is of the starboard side and the still pics are the other side . Keeping my fingers crossed on this one .
The wiring will need a lot of attention I'm afraid if everything else checks out .
I hope to see the manual in the mail tomorrow ...

 

[sphelps]

Starter came in today along with the manual .. That was fast ! Robbed mounting bolts off a 50 hp I have ..here are the compression numbers I ended up with ..
Cylinder # 1 - 105
2 - 104
3 - 105
4 - 102
5 - 106
6 - 103
Not sure if I was getting fast enough revolutions from the starter .
Battery was reading 12.4 volts off of battery terminals .. And the starter bendex gear? Was getting hung up on the flywheel . This was a cheap aftermarket new starter ..
Btw , this factory service manual is great !

 

[V153]

Sounds a lil low. But consistent at least. Do you have the carbs wide open?

 

[sphelps]

No I did not think of opening the throttle ...I read somewhere ,maybe in the sticky"s , that these older V6's run at a little lower compression . idk

 

[Bosunsmate]

Those numbers look ok to me, did you check that all the piston rings were springy?

 

[emdsapmgr]

Your compression is 4-7 lbs low. Hardly anything to get worried about-they are nice and even. Looks like you've got a winner! Now that it cranks, check for spark on each cylinder. A spark checker or inductive timing light will do the job. You'll want to closely look at all the fuel hoses and fuel pumps under the cowl. Original fuel components decompose when exposed to today's ethanol fuels. Black bits of fuel hose can migrate down into the jets of the carb, causing it to run lean. Unlikely these are original fuel components, considering the age of the engine-but check them.

 

[sphelps]

Thanks for all the help guys ! Not sure about the springy piston rings or how I would check ..
I need to replace the bypass cover gaskets now to kinda put things back together i guess ..
The part # I came up with is Sierra -18-2876-9 and OEM - 0307133
Does anyone know if these are the right ones ?

 

[Bosunsmate]

If the rings are seized in their grooves or snapped they wont spring when pressed in. I use a screwdriver with bit of tape on it and press them in through those holes in the bypass chambers you can see.
When you press them in you should feel them pushing back

 

[Bosunsmate]

I need to replace the bypass cover gaskets now to kinda put things back together i guess ..
The part # I came up with is Sierra -18-2876-9 and OEM - 0307133
Does anyone know if these are the right ones ?

Thats what i make out for a 175 hp 78 as well

 

[sphelps]

I checked the rings and they all seemed nice and springy ... Gunna order the gaskets .. Any preference on the sierra vs OEM ?
It did not come with controls or wiring harness . I do have the ones from the 50hp and from a 40 hp ... Do you think I can use these for testing ?

 

[Bosunsmate]

I checked the rings and they all seemed nice and springy ... Gunna order the gaskets .. Any preference on the sierra vs OEM ?
It did not come with controls or wiring harness . I do have the ones from the 50hp and from a 40 hp ... Do you think I can use these for testing ?

Thats good about the springy, one motor of my friends i checked had ok compression (even too) but 6 out of 8 rings were not springy and were carboned in or cracked.
Ive never had a problem with Sierra or OEM. I normally go Sierra as they are cheaper here.
Not sure about the controls but if they connect up and they advance the throttle and gearbox to where they need too then your luck is in.

 

[emdsapmgr]

Your engine has a red plug for the main control box harness. Any control box with a red plug 1973 and up thru 1995 will fit it. The only problem with a 40 or 50 hp control box is that it may not have the power trim button in the handle. Yes, it will run the engine for testing purposes. Somewhere in the mid 80's the control boxes added an emergency lanyard cutoff. Unless you fish in bass tournaments, it's not a big deal.