1998 90HP Evinrude Problems!

[webbd]

I saw what looks like heavy carbon on the piston and head, missed anything that looked like heavy damage except the lines in the cylinder walls.

The carbon on the piston and head looked like what I might expect in a low compression situation where it glazes and peels like a poorly seasoned cast-iron pan.

Did I miss other physical damage?

--DW

 

[webbd]

I saw what looks like heavy carbon on the piston and head, missed anything that looked like heavy damage except the lines in the cylinder walls. I assume those were due to broken rings.

The carbon on the piston and head looked like what I might expect in a low compression situation where it glazes and peels like a poorly seasoned cast-iron pan.

Did I miss other physical damage?

--DW

 

[Cooks]

Lack of spark has nothing to do with it !!!----It is poor design of the TOP piston ring that is the problem.

Alright just didn’t know if the previous owner running this thing without spark had anything to do with it.

 

[Cooks]

I saw what looks like heavy carbon on the piston and head, missed anything that looked like heavy damage except the lines in the cylinder walls.

The carbon on the piston and head looked like what I might expect in a low compression situation where it glazes and peels like a poorly seasoned cast-iron pan.

Did I miss other physical damage?

--DW

If you look closer that’s not carbon, that is pitting, burrs and gouges in the metal on the head and on the piston.

 

[racerone]

A broken piston ring is the cause.----Remove bypass cover on side of the block and see the broken ring / damage!

 

[Cooks]

A broken piston ring is the cause.----Remove bypass cover on side of the block and see the broken ring / damage!

Is this salvageable? Or worth salvaging?
Bought the boat (170 sunbird with trailer) for $2500. Small piece of the floor and seats need to be replaced, tach needs replaced, and now the motor issues. Don’t want to go down a rabbit hole of cost.
Suggestions and opinions are welcome.

 

[racerone]

Some will argue all day long.----I say it is fixable if you want to learn about doing it yourself.----If you have to run to a shop at $100+ / hr you will be shocked by the cost to repair this.-----I do not have enuff fingers and toes to count how many times I have seen this very same damage !!

 

[Cooks]

Some will argue all day long.----I say it is fixable if you want to learn about doing it yourself.----If you have to run to a shop at $100+ / hr you will be shocked by the cost to repair this.-----I do not have enuff fingers and toes to count how many times I have seen this very same damage !!

First off. Thank you so much for all the help this far!!!
Alright so I have no problem doing this myself, more so just need guidance on how to proceed. Am I going to have to pull the block and get it bored and redo all the pistons?
Only fixing one will cause an imbalance correct?
As far as fixing this issue for the starboard side cylinders, can I get away with a new head, piston and rings, or am I for sure going to have to take a trip to a machine shop?

I am glad you have the experience and the willingness to help a new guy like me. Greatly appreciated.

 

[racerone]

Step #1 is to take it all apart.-----You need to bore and fit 4 new O/S pistons.-------Do not overlook an inspection / reseal of the lower unit.----Be a shame if that blew up after rebuilding the powerhead.

 

[Cooks]

Step #1 is to take it all apart.-----You need to bore and fit 4 new O/S pistons.-------Do not overlook an inspection / reseal of the lower unit.----Be a shame if that blew up after rebuilding the powerhead.

Do you have an estimate of cost? Just in parts? A rough estimate is fine... just need something to help with what path I choose to move forward

 

[racerone]

Your location ?

 

[Cooks]

Your location ?

Sanford, NC

 

[racerone]

Do a search for websites with parts prices including rebuilt powerheads. ---Will help determine path forward for you.-----Looking at about $2400 for rebuilt powerhead.-----Gasket set included at that price.

 

[Cooks]

Do a search for websites with parts prices including rebuilt powerheads. ---Will help determine path forward for you.-----Looking at about $2400 for rebuilt powerhead.-----Gasket set included at that price.

Dang. That is a lot more than I’d like to spend... was originally thinking the motor needed some work but nothing to this extent. I guess it’s a learning lesson.
So a fully pre-rebuilt power head would be the $2400?
Would me doing the rebuild myself be cheaper, or is that what the $2400 is indicating?

 

[racerone]

Be about 1/2 that if you do the work yourself.--------You will see why they say-------B.O.A.T.-----Bring on another thousand.

 

[Cooks]

Alright, so I am starting to try and price out/ get a shopping list together for a new power head. I have found a few rebuilt power heads on eBay and I am wondering, with a new power head, what else do I need to get to put the motor back together with the rebuilt top end. Here is the Power head I've been looking at.
Also, once this is all put together again, does anyone have a how-to for setting up the timing.

 

[healey8390]

Alright, so I am starting to try and price out/ get a shopping list together for a new power head. I have found a few rebuilt power heads on eBay and I am wondering, with a new power head, what else do I need to get to put the motor back together with the rebuilt top end. Here is the Power head I've been looking at.
Also, once this is all put together again, does anyone have a how-to for setting up the timing.

EDIT: Original Reply was to wrong post.

You can rebuild the powerhead with new pistons and rings. Upper, mid and lower main crank bearings, and big and small end piston bearings. Along with a powerhead gasket set and thermostat set for A LOT less than $2400!!!

 

[Cooks]

EDIT: Original Reply was to wrong post.

You can rebuild the powerhead with new pistons and rings. Upper, mid and lower main crank bearings, and big and small end piston bearings. Along with a powerhead gasket set and thermostat set for A LOT less than $2400!!!

Yeah that’s what I was originally thinking... but what about the cylinders, just get them bored and run oversized pistons? Any estimate of how much machine shops usually charge to bore out the cylinders?

 

[racerone]

I do my own boring the old fashioned way.------But I saw a video of a machine that quickly locates the bore and does this work FAST.----But that shop may still charge $100 / hole to help pay for this machine.

 

[flyingscott]

Get a WSM kit for your motor will have everything you need to rebuild your power head.