90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

[DamianJP]

Hey guys

I worked on a early 90's Evinrude 25HP, the model number is now where to be found.


Job went smooth and the telltale went from weak to pissing like a race horse and my friend was happy big time.Been about 3 weeks to a month and just got a call from him he said it started to get worse and now it has "NO" telltale.

So I went over there and pulled the water tube off of the water/exhaust jacket (the one on the side of the motor) and felt exhaust (warm air) coming from the barb fitting the telltale hose gets hooked to. Exhaust is getting into the cooling area somehow.

I first I was like "Oh crap" this is gonna be the first call I get were I somehow screwed a job up. But when I got there I turned the flywheel and heard the impeller move. When he turned the hose on water was gushing from the muffs, when we cranked the engine the water gushing from the sides of the muffs went almost all away leaving me to believe the water pump/impeller job I did is fine because it's sucking water fine into the intake.

I think its either of 3 things.

1) Powerhead gasket (Between head and adapter plate and such)

2) Cylinderhead gasket (Should show a drop in Compression though, will test)

3) Exhaust/water jacket gasket(s) , area on side of engine

I need help to plan my next move to start to figure out what to do so I just dont shotgun parts into an area that is fine.


Thanks guys,
DamianJP

 

[restornator]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

since the telltail nipple is on the exhaust manifold where the exhaust is cooled, it has to be a blown inner exhaust cover.

 

[DamianJP]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

Thank you Res

If the gaskets of any other area's I mentioned are blown out too, would it produce the same symptom too?

Do these blow out because of age or can something promote the failure? Stuck thermostat or something?

When we cranked the engine for alittle bit that area got warm very quick, the exhaust manifold area.

Thank god all the bolts (well the whole engine) was maintained good and all the bolts are not rusted at all. The lower unit bolt that I removed when I did the water pump job came out with ease.

Ill focus on those though for right now.


Thank you Res,
DamianJP

 

[jgriner]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

my telltale started doing that, one time. It would frizz for a few min, before it started spraying, I had blown head gasket. give away was water in spark plugs and lost of compression on one of the cylinder

but hay im no mechanic

 

[DamianJP]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

Naw jgriner your right.

My Dad's 1977 55HP Evinrude had the same problem. Blowing steam ,bad compression on top cylinder, and crystal clean plug. Bad cylinder head gasket. It's in pieces right now awaiting a total 30 over bore / rebuild.

Was it a cylinder head gasket for you or the power head gasket?

I hope its just the 2 exhaust gaskets on the manifold with this 25HP Evinrude but if its not I just pieced together all the gaskets and 1 water tube grommet, around $50 for powerhead , 2 exhausts , water jacket , cylinderhead. If its just the 2 exhausts it will be around $15.

Im gonna check the compression and look at the plug tomorrow and eliminate some stuff.

DamianJP

 

[DamianJP]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

Also I just noticed that this motor has water deflectors in the schematics.

Ive never dealt with these. What are they purpose and symptoms if they fall out of place or they fail?

 

[Cofe]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

As you have noticed DJP, that problem could be caused by many different things. I tend to agree with jgriner about the head gasket. If a head gasket is leaking into a water passage, the exhaust pressure will overcome the water pressure and you will have symptoms as you describe. When you have the head off, the water deflectors are different lengths, and water needs to flow behind them to drain out of the block. You will notice a raised "***" in the area that each defelector sits. The deflectors are slid into place up against those tits, and that is as far as they are supposed to go. Pay attention to the lower right water deflector. Behind it is a small water jacket area that allows water to drain out down into the leg. That area is where trash....old pieces of rubber from the impeller like to lodge. You will need a strong flash light, and a mirror to see what I mean once you get there. Here is a link that may help you also. http://forums.iboats.com/showthread.php?t=359255&highlight=25+evinrude+deflectors

 

[DamianJP]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

Thanks Cofe !

Gonna break the news to my friend today when he gets up.

He caught this in time when the boat wasn't under load, in the back of his house he decided to warm the engine up cause he didn't use it for a week. Noticed the telltale was funny and called me. Do you think I should just find the problem and fix it or do you think the other gaskets got stressed from it doing this abit?

How should I attack this?

I was thinking of doing a compression test and looking at the plugs to see if its the cylinder head gasket.

Then if it's that attack it , if not move on to the next area?

Thanks guys , ya'll are awesome !!
DamianJP

 

[Cofe]

Re: 90's Evinrude 25HP Water pump just done and worked, now no telltale just warm air

DamianJP, I think a compression check would help, and remember, if the head gasket is leaking between the cylinders, you will get a erroneous reading because the cylinders will equalize out from that type of leak. In this case the numbers may be equal, but low. If things check out with the head gasket, second guess is the water cooled exhaust covers. After time they get brittle and cause internal leaks.
On my first attempt with a motor such as that one, I removed the plugs, removed the lower unit, and hooked a water hose up to the copper water tube. Water poured out of the spark plug holes and in my instance, both head and exhaust gaskets were bad.

Here is a water tube hose connection that I made up for testing from a old copper toilet fill line. A water tube grommet is on one end, and a old garden hose connection soldered on the other end. A motor can be ran without the lower unit with this tool.