1989 Johnson 110HP - teething issues

[CH1968]

Hi Team.

My very first post and I dearly hope you can assist me with my 1989 110HP JOHNSON 2 stroke VRO outboard.

I have spent countless hours on this baby and don't want to give her up.

Issue 1 - Overheating alarm comes on at close to WOT (4500-5000) RPM.
Issue 2 - I need to lift leg partially out of water (at ramp) to start.

Background to Issue 1 - Replaced water pump kit, thermostats, poppets, removed water jackets and cleaned out galeries, newplugs and water hoses. Donk is hot to touch when alarm signals. How do I remove this apparent overheating issue?

Backround to Issue 2 - Starts first go when ear muffs are working (less back pressure). When I hit the ramp, I need to tenderly lower/raise the leg so to minimise effect of back pressure. It coughs a bit, and then out I go for a day's boating. When anchored up and want to start again, I have to repeat this process. How do I eliminate this annoying process of starting?

Cameron

 

[tashasdaddy]

Re: 1989 Johnson 110HP - teething issues

will it idle after the initial start up? have you check compression, or all 4. usually the start up in the water coinsides with an idle problem. because of back pressure. idle speed needs to be adjusted. 650-750 in gear in the water. are your sure the tstat are opening. test in a pot of hot water, suspended them so the don't touch, and use a candy thermometer. i would usually say the impeller is failing when the alarms does what it is doing, not keeping up the flow for the rpms. but if the tstat is not opening or the wrong one, it will not cool. also could be a faulty sender. i also use one of these to just verify that it is running hot. should be around 140 -145 degrees F

"http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93983"

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

Thansk.

Brand new water pump kit - including impellor. Brand new plugs but pulled and discovered wet and black (rich mixture i think). Brand new t-stats and tested in hot water beofre install. Compression measures to spec on all 4 cylinders. Senders brand new.

I read alot on this forum abot this same issue - some have redeuced lenght in poppet springs by cutting in half - why is this good? Also, two small holes clogged in stat housing - coudl this be the problem?

Thoughts?

Cameorn

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

SHould I be hearing that little chirp when i first turn the key?

 

[tashasdaddy]

Re: 1989 Johnson 110HP - teething issues

the chirp is a self test of the system. clogged holes don' t let the water thru to open the tstats. i have mixed feeling on cutting the poppet spring. i think it lets to water thru before it should. but thats just my opinion, i'm no engineer,

 

[Chinewalker]

Re: 1989 Johnson 110HP - teething issues

When you replaced the waterpump kit, did you do it "by the book"? There is a tiny vent hole in the top of the plastic housing that can be plugged up if you're a little to generous with the sealant when installing the o-ring that sits between the plastic housing and the stainless cup. I chased that issue around on my 90hp for a few days before figuring it out. The vent allows the pump to maintain prime when the water pulls away from the stern at speed. Mine would pump all day long at no wake speeds, but get it above 3/4 throttle and it would start to steam up....
- Scott

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

THis water pump install subtleness has popped up many times in this forum and has got me really curious!

No, I did not install by the book. I don't recall seeing a tiny vent hole in housing - why so importnat?

"Mine would pump all day long at no wake speeds, but get it above 3/4 throttle and it would start to steam up...." - Exactly what mine does!!

Looks liek another "OFF WITH HIS LEG" activity - I am getting stronger by the day!!

What about this grommet thing that sits on top of housing - why is it so important to have this in place?

Best way to ensure it (grommet) does not move when installing leg back on?

Cameron

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

the chirp is a self test of the system. clogged holes don' t let the water thru to open the tstats. i have mixed feeling on cutting the poppet spring. i think it lets to water thru before it should. but thats just my opinion, i'm no engineer,

SHould I reduce length of my poppet springs?

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

When you replaced the waterpump kit, did you do it "by the book"? There is a tiny vent hole in the top of the plastic housing that can be plugged up if you're a little to generous with the sealant when installing the o-ring that sits between the plastic housing and the stainless cup. I chased that issue around on my 90hp for a few days before figuring it out. The vent allows the pump to maintain prime when the water pulls away from the stern at speed. Mine would pump all day long at no wake speeds, but get it above 3/4 throttle and it would start to steam up....
- Scott

Chine Walker - did you solve your overheating problem then - just by ensuring this little hole was clear?

Cam

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

if the grommet (that sits on thop of housing) was parched with cracks all around - would this greatly affect it's performance and reduce flow ?

Where exactly is this hole in housing? I see a little 2mm hole on side - is this it?

Cam

 

[Chinewalker]

Re: 1989 Johnson 110HP - teething issues

Hi Cam,
It's not so much a hole as it is a slot. It is on the underside of the top of the plastic part of the housing. Maybe 1/4-inch long and running on the radial from the center edge of the top outwards. It acts as a vent and is actually mentioned and pictured in the OEM shop manual as something to do properly. I had redone hundreds of pumps over the years and had long ago stopped using manuals for the procedure. Goes to show that even those of us who do a lot of these can still learn something new! I had been a bit too liberal with the sealant when installing the o-ring that goes between the SST cup and the plastic housing, plugging up the vent in the process. And yes, cleaning that out got rid of my overheat! This was after I had taken the thermostat housing apart twice, removed both heads and head covers, etc. It was a head scratcher... My local Johnrude tech suggested the vent, showed me the step in the manual where it was mentioned, and that turned out to be it...

- Scott

 

[tashasdaddy]

Re: 1989 Johnson 110HP - teething issues

you have a PM.

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

SHould I reduce length of my poppet springs?

if the grommet (that sits on thop of housing) was parched with cracks all around - would this greatly affect it's performance and reduce flow ?

What steps do I take to check my carbies and ensure it does nto run too rich?

Cameron

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

THe IR temp gun reads 44 dec C on right hand thermostat cover but 38 deg C on the left t-stat cover. THis is interesting and woudl liek your thoughts..

I also measured the head temps - both same at 47 degC. I know I have to measure on full load - that's tomorrow.

 

[apaulos]

Re: 1989 Johnson 110HP - teething issues

I had an earlier overheat post and ended up shortening my poppet valve springs. It was either that or pull the thermostats for testing. I live in Florida and the water here is 90F+ typically. I think your probably also close to the equator. Are you down-under?

Anyways... In my case, I believe I have a motor that is running a wee-bit hot and the local water temps put it over the top.

Here's something to try... go down to your local hardware store and buy some hose to run off your heads and out over the engine cowling. Idea is to bypass the thermostats, the poppet valves, stat housing, block and leg. Then take the boat for a ride at WOT with loads of water being pumped out the temp. hoses. Your heads and block should run super cold. If not, place a couple of clamps on the hoses to restrict the outflowing water a bit to give the water time to pick up heat from head and the block. This test will prove that there isn't a problem with water flow into the block and heads. At least not when
there isn't much back pressure.

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

Just back from a boating event and the results are in! ALL BAD NEWS :-((

Took it very close to WOT (after genle crusing around for 5 mins) and BANG - overheat alarm is triggered.

40 secs later I have the IR Temp GUn on each head - whilst at idle.

Head 1 - 84 degC.
Head 2 - 75 degC.

This means that the sensors are working as they should and I DO have a real overheating issue.

Thoights?

 

[tashasdaddy]

Re: 1989 Johnson 110HP - teething issues

yes it does, that converts to 183F 167F. should be 140-145F either the impeller is failing, tstat not opening, or poppet need to be replaced. flush the complete motor, are you running in salt water. where are you?

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

Thansk Daddy for your reply.

I live in Australia (very northern tip). 100% use in salt water. Regualr flusing of complete motor performed 1/week.

I removed both heads and t-stat assy today. Obervations - salt build up on top of t-stats, bit ugly inside t-stat manifold with salt/crud build up on inner walls of manifold. The water jacket was also ugly with salt build up in the cooling galeries but I do not think enough to warrant restriction of flow.

I tested these stats and both began to pop open at 61 degC. Both stats/poppets and springs are new and were replaced in Feb this year with probably 5 hours use - MAX.

Water pump (including impellor) is also new.

THoughts as to why this donk may be overheating now - wiht regards to this post and lasat post???

Cameron

 

[CH1968]

Re: 1989 Johnson 110HP - teething issues

I had an earlier overheat post and ended up shortening my poppet valve springs. It was either that or pull the thermostats for testing. I live in Florida and the water here is 90F+ typically. I think your probably also close to the equator. Are you down-under?

Anyways... In my case, I believe I have a motor that is running a wee-bit hot and the local water temps put it over the top.

Here's something to try... go down to your local hardware store and buy some hose to run off your heads and out over the engine cowling. Idea is to bypass the thermostats, the poppet valves, stat housing, block and leg. Then take the boat for a ride at WOT with loads of water being pumped out the temp. hoses. Your heads and block should run super cold. If not, place a couple of clamps on the hoses to restrict the outflowing water a bit to give the water time to pick up heat from head and the block. This test will prove that there isn't a problem with water flow into the block and heads. At least not when
there isn't much back pressure.

Thanks Apalous.

I need clarification on this post. How do I run hose off my heads? Exactly what do I remove or open up on the heads to do this?

Cam

 

[Solittle]

Re: 1989 Johnson 110HP - teething issues

While you have the heads off it would be a good idea to replace the deflectors. They look like 1/4" fuel lines and are in the water passages in the block.