Up-date 77 Johnson 85HP

[wa3ipb]

Hubby put new waterpump/impellar(again), new head gaskets, new coils, water deflectors and compression is back up to 100 on three cylinders. The bottom right cylinder is questionable because the threaded insert came out on the plug before we took the head off to replace the gasket. Apparently a previous owner stripped a plug and added a insert. Hubby tried to get the threaded insert off the plug to no avail so just screwed it back in (new plug attached). It was very difficult to get back in. The threading is a little off due to "trying" to remove it off the plug. So we didn't check compression on that cylinder after we replaced the heads. This may be a dumb blonde question but anyway of checking compression without taking the plug out? We haven't began the steering problem yet but jotted down the info. given to us on this wonderful board! Thanks again ! We'll give further up-dates soon I hope

Wifey

 

[Backlash]

Re: Up-date 77 Johnson 85HP

No way I've ever heard of to check compression without first removing the spark plug. Sounds like you'll need to put a new insert in the hole where the "threading is a little off" if you expect it to hold compression. You can buy the insert at NAPA or just about any other parts supplier. Hope all works out for you.

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Hi Backlash, Well he took the plug to a Kunkel's Auto a few days ago and the guy there said he didn't have that insert. So he came home and just screwed the plug back in(with insert still attached to plug). He'll do the removal of each plug to see if can tell if that cylinder is firing while idling. Thank you!

 

[Big Four]

Re: Up-date 77 Johnson 85HP

A Heli-coil is the insert you are talking about. Usually these are a one shot deal. If they back out of the head then the head is shot. They should lock in place. Your best bet would be to remove the head and take it to an OMC dealer or a machine shop and let them try to reseat a new heli-coil. Chances are most dealers will have a used head laying around. I see them all the time on ebay for 15-25 bucks, but a dealer will slam you 50+. You can call Barnacle Bills over here near me at 856-785-9455. He'll have the head, both new and used, but get ready cause he ain't cheap...<br /><br /> The next thing you need to know is 100lbs is kinda low for compression on that engine. She should be in 120-125 range to be completely healthy. Considering that you have 3 at the same compression it's entirely possible your compression gauge is wrong. I just say this because if the compression is equally down on all cylinders it indicates a high hour engine. I would try and borrow another gauge before you put much more money into her.<br /><br /> Another thing you should do as soon as you get her running and that's give her a good cleaning with either OMC Engine Tuner or Seafoam engine cleaner. Either one will remove any old carbon built up on the pistons or rings. This could also be the compression problem. Seafoam works faster, 10-15 min compared to 12+hrs with the OMC ET. Seafoam can be found at NAPA or CarQuest auto stores. Don't forget a fresh set of L77-JC4's Champion plugs for her.

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Big Four, Wow! That's not what we wanted to hear! I checked eBay last night but no 77 Johnson parts(heads) are available yet. Would a head from a closer year(1978?) possibly fit? I'll keep checking. What do you mean high hours? Possible tear down? We just finished putting the gearcase on Saturday but I need to buy gearcase lube today. Then we're hoping another compression check while the motor's warm will show us higher readings. I'll check into renting a better compression checker too. Salvo's rents some things. We just did a OMC tune-up de-carb last month and it hasn't ran much since then. Should we do it again so soon? I'll keep Bill's number just in case. We'll keep up-dating. Thanks again.<br />Wifey (ka3wld)

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Well we put the new water pump/impellar in, changed the last three coils to new (already changed other one ) and held our breaths as we fired up (with muffs/hose on!!) motor. AARRHHH!!! Water was only spitting out the tell-tale! Water "Was" seeping through/ between the gearcase and exhaust housing which makes us think we didn't align the plastic water tubes correctly to the grommets (exhaust housing). Dan (hubby) did use OMC Adhesive M on the impellar O ring and also on the gearcase and exhaust housing surfaces. Is there any trick to getting those plastic tubes to stay in place while hoisting the gearcase up to meet the exhaust housing? They kept slipping out of place and we thought we had them in this time. Also with this motor, we can't use the torque wrench we bought because there's a lip between the exhaust housing/gearcase that won't let us fit our torque over the gearcase screws!! Dan just tighened it hard as he could with a regular socket wrench. Woe is me!!! Any tips, hints opinions will greatly be appreciated..again

PS: Motor started on first turn but we still want to do a warm compression test when we're able.<br />Wifey (ka3wld)

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Anyone with ideas to the above post? Thank You! (ka3wld)

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

We bought two new water tubes and installed the gearcase "sure" the tubes were correctly attached to the pump housing. I said "the hec" with those muffs and went and bought a 50 gallon trash can, cut it to fit so we could just lower the gearcase up to about 3 inches above gearcase/housing with water. Fired her up and we both were so happy that water was coming out the tell-tale. We think we still have ignition problems, (maybe key switch?) because she stalled and we couldn't get her started again till Dan fulled with some of the wires/grounding and such. We also noticed water seeping through the old water hoses attached to the cylinders so I went and bought a hose from the auto shop. Dan cut and fitted the new hoses on with hose clamps. We fired her back up and guess what, NO WATER OUT THE TELL_TALE and motor got real hot to the touch. Why in the world would it work an hour before(tell-tale water) and not this time?? This is the second water pump/impellar in two months that we've put on. Please help!

 

[adrian bick]

Re: Up-date 77 Johnson 85HP

Running a motor in a barrel ( especially a big motor) puts way too much air into the water and water pumps were never designed to pump air and water it simply does not work.Is there not a good shop in your area ???

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Hi Adrian and thanks for your reply. The first time water came out strong from the tell-tale. Are you saying she stalled because air in the water? That would cause the water pump not to work at all the second time? Yes there are plenty of shops around.. just not plenty of cash at this moment

 

[Big Four]

Re: Up-date 77 Johnson 85HP

Yeah, first don't worry about the water coming coming out between the lower unit and the mid section housing. What you are seeing is the water from the exhaust being blown down exhaust chamber and you are getting few leaks. This water has already been thru the engine.<br /><br /> You had the copper tubes in if you saw any water from the pisser. Next you have a weak stream from the oisser because most garden hoses don't have the volume or the pressure to fill the cooling system on the engine like the water pump impeller does. You confirmed this by seeing a full stream when the engine was in the 50 gal drum. Stop judging your cooling sysytem on a hose. Too many do it and it doesn't work.<br /><br /> You can't use straight auto rubber hose on those lower head hoses. They are custom formed so they don't bend and pinch off the water flow. You'll need to get the right ones from a dealer. Once the engine warmed up, my guess is those hoses softened and folded/creased and stopped the water flow..

 

[Big Four]

Re: Up-date 77 Johnson 85HP

You can buy a compression gauge from Sears for 25 bucks. Renting one is a waste.<br /><br /> By "high hours" I mean the engine has had lots of use and the cylinder wear is normal. It's normal for an engine to loose compression over time. If they all wear the same it's a good thing.<br /><br /> I don't where Adrian got this idea you can't run an outboard in a barrel, but I've been doing it for 40 years without a problem. Everything thing from a 3hp to a 300hp from 1939 to 2000 year engines. <br /><br /> The biggest problems show from running them on a hose. An outboard water pump has the ability to move 10 times the water your garden hose does. The problem is when running on the hose the impeller is trying to pull more water than the hose can deliver. This creates air up in the engine and the pisser doesn't get a full supply of water. An outboard at idle(out of gear) doesn't need much water to stay cool and hose will usually work. Don't start and run the engine on the hose then walk away from it. Someone inside just flushing the toilet can ruin the engine.

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Thank you Big Four

Well... we went to a large Johnson dealer(where we've been getting most of our parts) and this guy told Dan that they didn't have them and to go get hoses from an auto store. AAHH! We took the cowl off after the second start with water not flowing and the hoses were not bent at all. Wish that was the problem though.

 

[Big Four]

Re: Up-date 77 Johnson 85HP

Pull those hoses off and then start her. That will tell you real quick if the water pump is working. Make sure you have water in the barrel up to where the impeller is in the leg. They are not self priming pumps especially when they are dry. On the boat they sit well submerged so priming is never an issue.

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Hi Big Four, we have the water line about 2-3 inches about gearcase. that enough? We'll pull the hoses and let you know the results. Thanks so much again

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Hello and thanks for responding again, ok, we pulled those water(auto) hoses and fired her up and water did come out. A little at first but then increased in volume after a few more seconds. Water is still refusing to come out tell-tale. We're going take the therm cover and water thing cover off to see if we can find a blockage to to tell-tale. Wierd thing is..it came out the tell-tale fine 1/2 hour before it stopped. If water is coming out the head holes, this means the impellar is still working correct? We're also going to put the old hoses back on and tighten them with hose clamps. The old clamps were just twisted wire clamps. Thanks again for all the help

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

Oh! OH! I forgot to mention happy news! we did a warm compression check and the 2 cylinders were at 120 third at 116. The fourth still needs the heli-coil fixed so we didn't check that one but the others were only at 100 during a cold check! Can I be happy about this? Maria

 

[wa3ipb]

Re: Up-date 77 Johnson 85HP

When Dan disconnected the tell-tale hose and blew it out, he saw bubbles right at the water line. It looks like our exhaust tube has vents at the top and we did not have the motor deep enough water. As soon as we added another four inches to our test tank, water flowed just fine out the tell-tale. We let her idle for fifteen minutes and darn if she didn't!!! We have shut her down for an hour and will make the same test again with water filled to barrel limit like as before. We have water running to the barrel constantly. This is another mistake we made. Not thinking about the water over-flowing and lowering due to turbulence from exhaust. At this minute it looks pretty good. we'll let you know ! Looking forward to a test drive this Saturday!

 

[ka3wld]

Re: Up-date 77 Johnson 85HP

Hello All! Just an up-date while we're here on vacation (laptop in tow . We've only one chance so far to go boating because of small craft advisories(high winds) here on Ocracoke Island(Outer Banks, N.C.. She did great!!! Hubby and I had nothing but smiles when we got back to the ramp. Sound fishing produced spot, croaker and a small flounder(all throw backs). Thanks and ((HUGS)) to all our friends here at Iboats for the wonderful help. It looks like we'll get another three days of good weather before heading home. Wish us luck! Wa3ipb's Wifey

 

[ka3wld]

Re: Up-date 77 Johnson 85HP

Hello All! Just an up-date while we're here on vacation (laptop in tow . We've only one chance so far to go boating because of small craft advisories(high winds) here on Ocracoke Island(Outer Banks, N.C.. She did great!!! Hubby and I had nothing but smiles when we got back to the ramp. Sound fishing produced spot, croaker and a small flounder(all throw backs). Thanks and ((HUGS)) to all our friends here at Iboats for the wonderful help. It looks like we'll get another three days of good weather before heading home. Wish us luck! Wa3ipb's Wifey