Cylinder Head 58 Evinrude 25936

[Trackbolt]

I am about finished the restoration of my father's old '58 Alumacraft and the 58 Evinrude 35. I went over the motor installed new waterpump, points, condenser and rebuilt the carb. The motor was in good shape after having been stored since 1996. I gave the cylinders a liberal dose of seafoam through the carb and plug holes when I put it up in 1996 and it paid dividends. I decided to remove the head to inspect the water passages as it is used in the Chesapeake bay. There was some corrosion and limey like deposits in the water jacket which were easily removed with a bottle brush. The head gasket came off with some effort delaminating and quite a bit of gasket remained on the head and block. I removed it with a plastic scraper then went to work with a scotch brite pad. I used a scotch bright pad on the head and block and was careful to only remove gasket remains. I installed a new head gasket and tightened it sequentially in three graduating cycles until the final sequence at 240 inch pounds. I installed the plugs hooked up the gas cranked the motor and it fired on first bump of the starter and ran nicely at an idle. But back at the head I had water spurting out at the top from between the head and block. I tried a l;ittle more torque on the bolts but no change. Shut down the motor and removed the head. Even had some water leaking in to cylinders. I sanded the head using a piece of sand paper taped to a steel plate until all die I used as indicator was gone. Straight edge check on block and head show both flat. I reinstalled the head and the thing still leaks. I re used the new head gasket. Should I have used another new one after pulling the head? I'd like to put this project to bed sometime soon.

 

[nwcove]

Re: Cylinder Head 58 Evinrude 25936

not sure what you have going on, but do question the use of steel plate as a flat surface to lap the head, as compared to plate glass. jmo

 

[F_R]

Re: Cylinder Head 58 Evinrude 25936

Put that straight edge against the block. Something sure isn't flat.

OR......Have you got the correct head bolts? hardware store bolts may run out of threads before they actually are tight.

 

[Trackbolt]

Re: Cylinder Head 58 Evinrude 25936

Thank you for the replies.
The steel plate is a piece of 1/4" steel that I have used for years on one and two cylinder air cooled Kohler engines to dress the heads. I always lay the straight edge on it before I use it to be sure. It is good. F_R, I am going to check the block again tomorrow I had the straignt edge on the block and it was good from the angles I could check but I might have missed something. If I need to lap it too how much will be too much considering I have already lapped the head? As far as the head bolts go they are the original bolts. No corosion but I hit them with the wire wheel and used a tap to clean out the bolt holes in the block and blew them out with compressed air. Used no sealer on gasket or head bolt threads. When I cleaned the head an block I used a fine scotchbrite pad on my air die grinder very lightly to remove any gasket material stuck on the surfaces that would not come off with the scraper. I finished it up by hand. I must have done something to cause this as it did not happen by itself with the motor in storage for all these years.

 

[Trackbolt]

Re: Cylinder Head 58 Evinrude 25936

I am going to remove the rear portion of the lower cowl and take a closer look at the block surface.

 

[Tim Frank]

Re: Cylinder Head 58 Evinrude 25936

Where did you get 240 in-lbs? Sounds pretty high.
Where are you starting your tightening sequence?

 

[Trackbolt]

Re: Cylinder Head 58 Evinrude 25936

The manual says 240 in lbs or 20 ft lbs. Because it is a Selock manual I questioned that and the Evinrude mechanic nearby where I got the head gasket verified 240 inch pounds is correct for that motor. I began with the middle bolts and worked out completing at the top and bottom. I began the first round with 80 in lbs, second round with 160 in lbs and the third at 240 in lbs. When installing a head I usually run the motor after the third round until it reaches normal operating temp and check the torque again. Because of the leaking I did not get that far.

 

[1946Zephyr]

Re: Cylinder Head 58 Evinrude 25936

Well, I believe those are 3/8" bolts on that motor, so 240 in pounds would be about right. According to my Johnson service manual, for the same year Johnson 35, it does call out 216 - 240 in pounds for the cylinder head bolts.

 

[Trackbolt]

Re: Cylinder Head 58 Evinrude 25936

I found a nice piece of 1/4" glass plate. I cut it to size tape a sheet of 230 grit sandpaper to it and will use it to lap the block surface and I will re do the head too. I made a couple of cardboard plugs to seal up the bores when I surface the block. I'll use a Sharpie to color the mating surface then sand until it is all removed. This is the first time I've ever had to do the block deck.

 

[Tim Frank]

Re: Cylinder Head 58 Evinrude 25936

The manual says 240 in lbs or 20 ft lbs. Because it is a Selock manual I questioned that and the Evinrude mechanic nearby where I got the head gasket verified 240 inch pounds is correct for that motor. I began with the middle bolts and worked out completing at the top and bottom. I began the first round with 80 in lbs, second round with 160 in lbs and the third at 240 in lbs. When installing a head I usually run the motor after the third round until it reaches normal operating temp and check the torque again. Because of the leaking I did not get that far.

That's how it's supposed to be done!

Maybe check for a score across the outer sealing area on the block....
Did you run it with the cover off before mothballing it? Maybe it was leaking a bit before.

 

[Trackbolt]

Re: Cylinder Head 58 Evinrude 25936

What I found this afternoon after about an hour of dressing both bloc k and head was a couple of spots where I might have applied too much pressure with the scotch bright wheel on the die grinder. Right in the area where I had a leak on the top is a boss that connects the block water jacket to the head's jacket. I might have tarried too long with the scotch brite pad. There were a couple of other areas not as bad but now I can magic marker the sealing surfaces and with a couple of figure eights with 320 grit cleans the whole thing. Same for the block. Straight edge and light shows no light at the sealing surfaces. I am going to get a new gasket and new head bolts tomorrow. That should do the trick. My cardboard plugs in the cylinder work like a champ. After I install them I put a little bead of grease around the edge to trap any grit. I also vacuum the area each time I check with the straight edge to keep the grit to a minimum. As I pull out the cardboard plugs most of the grease comes with them and what remains is right at the edge and an easy cleanup with a rag.

 

[F_R]

Re: Cylinder Head 58 Evinrude 25936

Evinrude service manual says 220-240 inch pounds for 1958-59. Seems odd because earlier models was 160-195. They are 5/16" aren't they?

EDIT: Gale service manual says 18-20 ft pounds (216-240 inch pounds)

 

[HighTrim]

Re: Cylinder Head 58 Evinrude 25936

I was going to say, you need to use something very flat, I use plate glass. Steel is not straight. Not rough plate steel anyways. Figure 8s is the way to go. Usual low spot is between cylinders. You will never get it true with a grinder like you were doing.

 

[HighTrim]

Re: Cylinder Head 58 Evinrude 25936

This should help as well

 

[Trackbolt]

Re: Cylinder Head 58 Evinrude 25936

I am greatful for all of the guidance. I did find a piece of 1/4' plate glass and cut it small enough to handle easily. As I said earlier I lapped both block and head and am pleased with the results. I was given some bad advise about the die grinder. Should have known better. At least I kept the pressure light and did not do any more damaged than I did. Any both block and head are clean and flat. Can I re use the new head gasket since I have already torqued it and can I re-use the original head bolts? The local shop will no doubt have to order new ones. I am going to put up a couple more pictures. The glass is before I cut it to fit and taped the abrasive paper to it. Used 400 then 800 grit to polish out all the roughness from the 230 grit paper. The picture is before I did that.