Head gasket change Evinrude 140

[archcycle]

1990 Evinrude 140

About a year and a half ago a shadetree mechanic (who for a price taught me that it was best do to my own work and that's about all I got for my money..) replaced my head gaskets (and broke a few other things). He clearly didn't tighten them down very well and there's been a fair amount of leakage. For a while I had been getting a tiny bit of gunk buildup around the head bolts. Barely anything. Then suddenly it became a lot so I'm changing them. Again. I'd managed to convince myself the water got there from the slightly cracked and leaky thermostat cover that came on a head he swapped out for me (which had a broken thermostat bolt when I bought the motor). Thanks, guy. Lately its gotten really bad so I'm finally replacing them.

As long as I have it all apart I thought I'd get a few opinions on the condition of these internals. These pics are the port side. It looks like there is a little bit of scoring in there and I'm wondering if this is bad scoring or normal wear.

The compression is port top 135 port bottom 125, and both starboard are 135. I suppose part of the low compression on that one cylinder could be due to the fact that the head gasket just wasn't very tight.

And how about that carbon buildup? I did a concentrated sea foaming about a year ago and I'm due for one now, but while this is apart can I just scrape that out and then blow it out with my air compressor? Or is it even that bad?

 

[emoney]

Re: Head gasket change Evinrude 140

I would say the compression readings are good enough to assume that scoring is just normal wear. And yes, if the head bolts weren't torqued right, that could caused the 125/135 diff, but even then, it's within spec (10% difference or less)

 

[AlTn]

Re: Head gasket change Evinrude 140

would suggest you check the heads with a straight edge for warpage and dipping...then surface them on a flat surface using the figure 8 pattern on 150 or so grit emory paper..you can scrape the carbon on the piston tops and blow it out with your compressor, wipe it with a cloth too for that matter..it's gonna get blown out the exhaust most likely anyway..no real need to try to "polish" them

 

[levi_tsk]

Re: Head gasket change Evinrude 140

i see three things here and youll want to make sure you do it next time
#1 those head bolts arent sposed to be very tight.... pretty sure my book say 15ftlbs which isnt much
#2 after ten hours of use they are supposed to be retorqued im assuming since you were displeased with his work you didnt take it back to him for this but did you retorque them youself?
#3 be VERY careful scraping the pistons and blow everything out REALLY good if not a chunk of that carbon can get stuck in a ring and break it and then youll be looking at another rebuild

 

[archcycle]

Re: Head gasket change Evinrude 140

Thanks all. My manual has them at 20lbs so that's where they'll go and this time around I'll make sure that I check up on them after 10 hours.

So far this morning I've gotten started scraping with a dull scraper and light sandpaper and an air compressor blowing it out a lot and blowing in circles around the rings to keep junk from building up in there. The pics look like they have some scored up areas but its mostly just shiny reflection in the pic.

 

[archcycle]

Re: Head gasket change Evinrude 140

I put the head back on and compression tested. Last time the motor was warm and it was a little dark out which could have affected my readings.

Port top and bottom (the side i just did) are both exactly 130
Starboard top and bottom are 135 and 130

They cleaned up nicely I think. There was virtually nothing on the cylinder walls, just the pistons.

 

[archcycle]

Re: Head gasket change Evinrude 140

Starboard head thermostat cover had a broken EZ out in it courtesy of the previous owner. Part of this job is finally putting thermostats in it (it came with none and there always seemed to be more important places to attach $100 to this motor) so I decided to just have a machine shop do it right. Not bad, $65 including a helicoil and a new bolt, and I had to call 3 machine shops to find one that was willing to get the EZ out out. The first two went ohhhhh sorry we don't do those. Is it really that much of a pain in the *** even with a drill press? That makes me want to throw out my set.

They repainted the head black for me and now I'm wishing I'd repainted the port head while I had it off. The corrosion from the water leaks (which I'd mostly drill brushed off but there was still staining. very thoughtful of them.) and the fact that it is from that "mechanic" and had a dull matte finish which doesn't match the shiny finish that the rest of the motor got during its rattle can rebuild from the shop that sold it to me, really doesn't match.

I've torqued it down and turned it over a few times for the compression test but haven't fired it up yet with that head gasket in. I know you aren't supposed to reuse them but would this situation be ok to take it back off, paint it, and reuse the gasket?

 

[archcycle]

Re: Head gasket change Evinrude 140

Starboard side cleaned up Way easier than the port. Starboard top was pretty flaky and barely needed any solvent. Solvent did more to shine it up than clean it. Then the bottom was quite clean and good looking, barely anything in there at all. Same deal where it was very flaky and came right off then shined it up with the solvent.

Oddly the compression dropped again.. this time the starboard top was just over 125 bottom just under 125.. It is encouraging though that they are both just about even, whatever the case there. I didn't test the port side to see if there were just different conditions giving different readings.

Going to let it get good and warmed up with its brand new thermostats tomorrow after work and see what all 4 say.

 

[RZR2007]

Re: Head gasket change Evinrude 140

Starboard head thermostat cover had a broken EZ out in it courtesy of the previous owner. Part of this job is finally putting thermostats in it (it came with none and there always seemed to be more important places to attach $100 to this motor) so I decided to just have a machine shop do it right. Not bad, $65 including a helicoil and a new bolt, and I had to call 3 machine shops to find one that was willing to get the EZ out out. The first two went ohhhhh sorry we don't do those. Is it really that much of a pain in the *** even with a drill press? That makes me want to throw out my set.

They repainted the head black for me and now I'm wishing I'd repainted the port head while I had it off. The corrosion from the water leaks (which I'd mostly drill brushed off but there was still staining. very thoughtful of them.) and the fact that it is from that "mechanic" and had a dull matte finish which doesn't match the shiny finish that the rest of the motor got during its rattle can rebuild from the shop that sold it to me, really doesn't match.

I've torqued it down and turned it over a few times for the compression test but haven't fired it up yet with that head gasket in. I know you aren't supposed to reuse them but would this situation be ok to take it back off, paint it, and reuse the gasket?

Yes a broken easy out is a bear to get out sometimes, solid carbide is about the only thing that will go through it! $65 is a good deal. If you buy another compression tester, chances are it will not read the same as the one you are using now, you have good numbers across the board....

 

[archcycle]

Re: Head gasket change Evinrude 140

Definitely OK with $65 instead of several $10 bits and half a saturday Afternoon!

Just tested with it fully warmed up and got the compression numbers I was looking for. They all almost instantly banged up to 130, and two eventually got 132 or so and two hit 135! I know the previous numbers were just fine but I was a little curious about whether the drops were just attributable to it being completely cold (relative considering Florida in July..) after the new head gaskets, but yes, it just needed to be warm to get the same numbers I got before. Nice.

And just in time for the Blue Angels weekend giant boat gathering sandbar party

I want to paint back over the head bolts now that I drill brushed them all rust and corrosion free. Is Por-15 good for marine applications like this? I'd like to brush some shiny black rust inhibitor on them.

 

[RZR2007]

Re: Head gasket change Evinrude 140

Isn't summer in Florida great! lol. I don't know about the por-15, I would just spray with some decent paint, as long as the bare metal is sealed, you will be ok, the por-15 does NOT like to come off!

 

[archcycle]

Re: Head gasket change Evinrude 140

I'm a little uncomfortable with the temperature of the water coming out of the telltale. Without the thermostats it was always pretty cool, the same as or a little warmer than the water it was taking in. Now when I first ran it at the dock, it was idling and peeing just fine, so I went to park my trailer and when I got back it was HOT coming out of there. Very hot. No temp alarm though (I know the alarm works but don't know whether the sensors work..). Shut it off and waited a few moments and started it back up and ran up the RPMs some and it started cooling a lot better. Throughout the day it was generally a bit hot, especially at idle, and cooler after running harder and I guess getting more water.

Most of the day it was hot but not to the point that it was really uncomfortable to put my hand under it. The one time I popped the cowling off I could hold my hand on any part of the head for at least a few seconds but I'm still uncomfortable with it. Is this just the way they run?

I'm wondering if maybe the motor had just always run way too cool and now it just seems strange to me seeing it run warmer?