1992 Evin 90hp Water Pressure gauge Issue

[MuskyHunterDave]

Re: 1992 Evin 90hp Water Pressure gauge Issue

I am not sure exactly where you are saying to locate the new hole . . . . are you saying to go high on the block above the factory elbow, drill a new hole, insert a plastic <-yikes T, run the line from the factory lower elbow through the T and to the Pee fitting, then tap the T at the higher position for the pressure sensor . . . ??<br /><br />SO what you are saying is that this will vent the water jacket for air build up, but will give the same pressure readings i am currently seeing, as stated above. . . Right . . . This is addressing the water jacket air venting issue you say is a problem with this motor? Is it really an issue that has arose i.e. trapped air ?<br /><br />Is it not reasonable to say any air in the jacket would be pushed out the pee line as it is the point of least resistance, beit high or low on the block, even though high only makes sense and should have been the factory location.<br /><br />Dave

 

[MuskyHunterDave]

Re: 1992 Evin 90hp Water Pressure gauge Issue

I forgot to add, what kind of Plastic T are you using as well, and how is it permenantly affixed so as not to leak?<br /><br />also, could you go into a little more detail as to the issue of trapped air in the block, how previlent is the issue, what is the result on the engine of the air being trapped, and in what conditions of motor use is this most commonly found.<br /><br />I am intrigued with this new issue, and would like to fully understand it.<br /><br />Thanks again,in advance, for the advise

 

[Silvertip]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Take an empty bottle and try to fill it from the bottom up. The air in the bottle is trapped near the top and compresses so you can't possibly fill the bottle. However if you tap a hole in the top the air can escape and the bottle will fill. Same thing happens at the highest point the engine block. Remember, unlike a car, the cooling system on an outboard is open meaning you take water in, force it through the engine and expel it again. Any place that can trap an air bubble will run hot because no water can reach that spot. That's why the tell tale is placed at the highest point on the engine because that's where air is likely to be trapped unless an escape route is available. Your engine does not have this problem unless you plug the telltale.

 

[JC1933]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Thank<br />s verry mutch Dhadley for your time. <br /> .. Claude..

 

[JC1933]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Thank<br />s verry mutch Dhadley for your time. <br /> .. Claude..

 

[MuskyHunterDave]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Upinsmoke. . . .<br />The tell-tail line comes fromt he bottom of the block on my motor, not the top as you think . . . . . Thats the issue I was trying to discuss with dehadley

 

[Silvertip]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Sorry -- I'm thinking of the three cylinders that had the service bulletin regarding repositioning the tell tale. The same principle applies however. Plug the tell tale whereever its located and you can still trap air somewhere in the block. Leaving it open and T-ing into the line does not upset anything.

 

[Dhadley]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Yep, we use a plastic T (E/J #337594) which is just like the plastic elbow already in your motor. From that elbow the hose goes up & over the starboard side of the block then down to the fitting in the pan.<br /><br />We tap into the water jacket at the highest point of the block, right above #1 cylinder. On a crossflow theres a flat area thats easy to use. We go into the block -- not the head. The hose goes right over that area anyway. Once the T is there we just cut the hose, put one end on each side of the T and youre done.<br /><br />Because of the basic design of the water passages air can be trapped up there. The T gives the air a way to escape. You dont lose any water because the hose is only so big. The pressure remains the same. The only difference you'll see is that on initial start up the water may "spit" for a few seconds then become a steady stream. The "spitting" is the air coming out.

 

[Rudy Brown]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Dhadley. I'm sorry if this is getting repetative for you but I just want to be sure that I'm clear on this. My 1984 90hp has the "P" hose connected to a elbow thats mounted on the bottom rear starboard side of the exhaust cover(I assume like Daves). I'm supposed to leave that alone, and drill a hole(and tap) into the top of the block above the #1 cylinder(starboard) and install the "T" there. Then run the "P" hose from the original elbow to the "T" then to the fitting in the pan. What size drill bit do I use? And tap? And then place a regular "T" in the line to run to the pressure gauge? I guess that the "T" (E/J#337594) is threaded on the bottom to screw into the block I just tapped? Again I'm sorry to make you repeat yourself, I just dont want to go drilling and tapping holes in my motor until I'm sure what I'm doing. And thank you Dhadley, Upinsmoke, and Walleyehed for your patience with us noobs. Rudy.

 

[MuskyHunterDave]

Re: 1992 Evin 90hp Water Pressure gauge Issue

To: DHADLEY<br /><br />Well it sounds like an easy task, or is there some dismantleing required ? Is there any chance of a picture of the aplication installed, so as to alleviate any possibility of error? I am real capable honds on guy, but it is real nice to be certain when doing things like this.<br /><br />Also, how concerned should I be about this trapped air issue? Was this a Major problem with this motor, and what is the hisory of damage as I asked before??<br /><br />It is a new motor to me, but the last guy haas been running it that way for Years . . . I guess I will try and find the (E/J#337594) "T" then I will do it when it warms up more, but I sure would like to see a picture if at all possible.<br /><br />Also I am not sure you addressed my question as to the pressure readings I was getting when I last had the boat out . . . .<br />So is the 5 lb just above idle "guage starts at 5" & 14/15 lb pressure reading at WOT = high / low/ or normal ??<br /><br />Thanks Dehadley again in advance for your reply

 

[Dhadley]

Re: 1992 Evin 90hp Water Pressure gauge Issue

It's a relative easy deal to install the T. That BRP plastic T has the same threads as the plastic elbow that's in the water jacket cover. 1/8" pipe I believe but that may not be. Dont drill or tap until you have the parts.<br /><br />The first time you do it you may want to wait until you have the heads off to see into the actual water passage. It isn't very deep so be careful.<br /><br />It's not something that has to be done. There are tens of thousands of V4 crossflows running around without it done. <br /><br />Dave, the idle pressure is about 3-4 lbs and wot pressure is about 18-22 lbs on a crossflow with the standard pump. That should be fine. There are some non OMC / BRP gauges that read a bit lower. Just get your baseline with a new pump kit and you'll be good to go.

 

[Rudy Brown]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Thanks for the reply Dhadley. I didnt even think about pulling the head. I need to do that anyway to replace the rubber deflectors there. Thanks again, Rudy.

 

[MuskyHunterDave]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Thanks Dhadley<br /><br />I will wait for that when the needs arrises to remove the head.<br /><br />Thanks again for al the info !!!!!!

 

[Dhadley]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Anytime guys!! If you need anything, please let us know.

 

[JC1933]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Hi guys.<br /><br /> Well i installed my water pressure gauge, now i have to hook it up to the motor, I found an Allen head plug right at the bottom back of the motor would this be the plug you were referring to Dhadley? thanks for your time...Claude.

 

[JC1933]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Bump.

 

[Dhadley]

Re: 1992 Evin 90hp Water Pressure gauge Issue

If you have an older crossflow, that's it.

 

[JC1933]

Re: 1992 Evin 90hp Water Pressure gauge Issue

Dhadley<br /><br /> It is not a cross flow it is a 1995 130 Johnson looper.<br /><br /> the plug i mentioned is at the bottom back right side of motor.<br /> It is the only plug on that side of motor.<br /><br /> Thanks for your help..Claude.