1977 85hp electric low compression on port cylinders

[leckbass]

That was my mistake the 85 and 115 are the same block and when you get old, you forget tech bulletins. The 85 HP is NLA, but www.marineengine.com has them for the $53.00 price I'd get them while I can.

All good, thank you on double checking

[leckbass]

So this is where I'm at... I tilted the motor up as high as I possibly can and I dropped the nose of the trailer as low as I possibly can. I turned the motor until I have the number 4 piston almost at the top. Then I filled the cylinder with Evinrude engine tuner

I let it sit for about an hour and then I started wiggling the Piston around with my fingers. I am surprised the piston can wobble back and forth. This is all new to me so maybe it is normal...

[omcforever]

85hp up to around 1979 had a 3.375 bore and 115hp had 3.50 bore. Different head gaskets.

[omcforever]

Lots of piston movement can mean froze/coked up rings or cylinders just wore out. I have most gaskets but the head gaskets for a 3.375 bore 85hp.

[omcforever]

Might want to run the pistons all the way down and mike the cylinders,,,,,,,while heads are off.

[leckbass]

Lots of piston movement can mean froze/coked up rings or cylinders just wore out. I have most gaskets but the head gaskets for a 3.375 bore 85hp.

I wouldn't say a lot of movement, maybe .5mm

[316jughead]

E-Bay has listings for 0318662 head gasket

[leckbass]

E-Bay has listings for 0318662 head gasket

I'm thinking about ordering one, but I want to check the compression again first before I get a new one. Thinking about using some sealant around the metal ring putting it back together, taking another compression test and seeing if anything changed. Don't want to waste money on gaskets if this motor is toast

[316jughead]

OK, whatever.

[leckbass]

OK, whatever.

Not a good idea?

[leckbass]

I had the engine tuner cleaner sitting in the cylinders for 24 hours. I put some Evinrude gasket sealer on the head gasket, put it back together. I let it sit overnight then started the motor, ran it for 20 minutes, then did a compression test and had the exact same results. 90 lbs on the starboard side 60lb on the port side.

I may just bring it over to the lake after work tomorrow and give it a quick run.

Should I bother ordering the head gasket? Or should I throw it in the junk pile?

[omcforever]

I had the engine tuner cleaner sitting in the cylinders for 24 hours. I put some Evinrude gasket sealer on the head gasket, put it back together. I let it sit overnight then started the motor, ran it for 20 minutes, then did a compression test and had the exact same results. 90 lbs on the starboard side 60lb on the port side.I may just bring it over to the lake after work tomorrow and give it a quick run. Should I bother ordering the head gasket? Or should I throw it in the junk pile?

Never re-use head gaskets...re-read post#25 and post#17. Mike the cylinders and while you are at it, remove transfer port covers and visually look at rings, check for seized-frozen. MIKE THE CYLINDERS! May have a worn out motor/rings/cylinders. Those cylinders in the pics look pretty scored up as well.

[omcforever]

Have you verified vernatherms are there and if they work properly? A missing or non functioning vernatherm for a long time could explain more wear on one bank or the other as well.

[leckbass]

Have you verified thermostats are there and if they work properly? A missing or non functioning tstat for a long time could explain more wear on one bank or the other as well.

Thermostat is in there, I checked it about five years ago when I bought the motor, also replaced the water pump impeller at the same time.

[leckbass]

Never re-use head gaskets...re-read post#25 and post#17. Mike the cylinders and while you are at it, remove transfer port covers and visually look at rings, check for seized-frozen. MIKE THE CYLINDERS! May have a worn out motor/rings/cylinders. Those cylinders in the pics look pretty scored up as well.

I'm not going to waste the money on a head gasket unless I know this thing is going to work. I will see if I can rent a cylinder Mike tool from the auto parts store. I have not removed the transfer port cover yet, I can do that next

[omcforever]

Thermostat is in there, I checked it about five years ago when I bought the motor, also replaced the water pump impeller at the same time.

Test the vernatherms/check pressure relief springs and valves,,after you check cylinders to see if it is worn out,,,,,. 5 years on an impeller is a long time and vernatherms do go bad so dont assume that since they where there 5 years ago then the are ok. Could be original..never know. Heads are off so most of the work getting to em is done. Check every little detail while apart....all can add up to issues.

[omcforever]

Water pump/vernatherms(johnson had vernatherms/my bad) -
http://www.bbcboards.net/showthread....523&highlight=

so vernatherms where never checked or verified they where there?

[leckbass]

Water pump/vernatherms(johnson had vernatherms/my bad) -
http://www.bbcboards.net/showthread....523&highlight=

so vernatherms where never checked or verified they where there?

I checked it right around the same time as the water pump, so about 2 years ago.

I'll tear back into this tonight.

[leckbass]

When I take off the exhaust port and look at the Rings, how do I know if they are stuck? Should I be able to move them?

If they are stuck ... What can I do to unstick them?

[omcforever]

When I take off the exhaust port and look at the Rings, how do I know if they are stuck? Should I be able to move them?

If they are stuck ... What can I do to unstick them?

Push on the ring with a screw driver but dont over do it and break it. Sometimes they cant be un stuck. De-carb done properly can sometimes un stick them,,sometimes not. Mike the cylinders first. .