Pressure test gearcase-how many pounds.

[daveydoodle]

Hello, Have a 1997 evinrude 2 cy. Very little water evidence when changed fluid at end season. Have the case off and would like info on lbs. settiing when I do a pressure and vacume test , had a guy said 3 lbs??? Need the expert opinions before I have all the seals replaced. Thanks, Dave== Happy veterans day and happy birthday USMC. Semper-Fi.

 

[lindy46]

Re: Pressure test gearcase-how many pounds.

I usually pressure test at 10psi for one hour.

 

[Mas]

Re: Pressure test gearcase-how many pounds.

I usually test at a lower pressure...such as 4-5 psi for several hours or overnight. It's best to do a dynamic test by turning the driveshaft too. Higher psi tests may allow the seals to close down on the shafts tightly giving the impression the case is sealed.
You should also do a vacuum test if double seals are used.

Mas

 

[Faztbullet]

Re: Pressure test gearcase-how many pounds.

I usually test at 10 psi pressure and 15 on the vacuum.

 

[ward cleaver]

Re: Pressure test gearcase-how many pounds.

Could you explain how you go about doing a pressure test...what tools you need?

 

[seahorse5]

Re: Pressure test gearcase-how many pounds.

If you follow the service manual, you test at 2 pressures, first at 5-6 psi then at 15-16psi. You should also vacuum check the gearcase to do a complete inspection for any leakage.

 

[Mas]

Re: Pressure test gearcase-how many pounds.

Alright...Question:

Anybody know the range of pressure/vacuum buildup during gearcase operation?

Mas

 

[Mi duckdown]

Re: Pressure test gearcase-how many pounds.

I'm thinking Zero vacuum. Pressure? Has got to be minute, if at all.

 

[daveydoodle]

Re: Pressure test gearcase-how many pounds.

To ans. question on what tools. After checking this forum on similar original questions I ran across several pieces of info. Simple to build one, a pressure guage, hose to attach to the fitting that screws in to the gear case at the filler hole. This may be simplified ans. but doesnt sound too difficult. My son has the tool for this that he made, but I would advise to check out the other entries I mentioned. Thanks to all for all the info I got onmy question.....

 

[Mas]

Re: Pressure test gearcase-how many pounds.

I'm thinking more...
During operation, the gears create friction...which creates heat (albeit not a lot) and thus pressure in a sealed case. Problems arise when the seals start to fail. As he case cools, a vacuum (due to pressure lost during operation) is created drawing in water past the seals.

Just wondering...
mas

 

[boobie]

Re: Pressure test gearcase-how many pounds.

When you're doing these tests don't forget to rotate the D/S , P/S and run the shift rod through the gears. Seahorse has the right specs for both pressue and vacuum.

 

[Faztbullet]

Re: Pressure test gearcase-how many pounds.

Anybody know the range of pressure/vacuum buildup during gearcase operation?

Run your motor for about 20 minutes,crack the oil screw and see if it has pressure (have a rag and soap handy)

 

[boobie]

Re: Pressure test gearcase-how many pounds.

If it has a bad bearing in it you may have to take good shower. LOL. But seen it happen.

 

[1946Zephyr]

Re: Pressure test gearcase-how many pounds.

You may have to take a good shower?.......or do you get to get a good shower? Hmmmmm pressure in a lower unit? A leaky seal? Lower unit under water? Looks like the good ingredients for a good shower fellas. LOL

 

[daveydoodle]

Re: Pressure test gearcase-how many pounds.

Fellas, I didnt add on to my question that I already pulled off the gear case from the motor, its on a pontoon boat on blocks for winter. I was trying to avoid a service call $$ . I guess now I am somewhat limited on my tests, I cannot start and run thru the gears as mentioned. Just wanted to be sure I do have a seal issue. Boat is kept on an all sports lake but gets alot of bass/pike fishing, althouth There was no line visible under the prop shaft. AmI ok withthis so far?? Guess I am now unsure how many lbs. to test at.

 

[Sprky]

Re: Pressure test gearcase-how many pounds.

Run your motor for about 20 minutes,crack the oil screw and see if it has pressure (have a rag and soap handy)

Don't be tellin tales FB. You know that these things never build any pressure.

Mas.... It's very important to get your face down close to the drain plug so that you can see the first few dribbles that come out....................

 

[boobie]

Re: Pressure test gearcase-how many pounds.

Davey, check post # 6.

 

[daveydoodle]

Re: Pressure test gearcase-how many pounds.

Thanks boobie ---service manual it is. Dave

 

[HighTrim]

Re: Pressure test gearcase-how many pounds.

I am going to throw my own spin at this.

If I have a leaky gearcase, I reseal it period. I just cant see going through the trouble of pulling the gearcase apart, swapping the propshaft seal since that is all you saw leak from a pressure test, yet leave the others. I just find it cheaper to buy the re seal kit (where applicable), than to purchase them individually year to year and service them one at a time. Do it all once and be done with it, forget about the tests. Unless it is either that or vaccuum the house with the wife, then by all means test away!

 

[daveydoodle]

Re: Pressure test gearcase-how many pounds.

High trim, Totally agree. I wanted the learning experience plus I can pass thisalong to the guy that I am going to have do it. I am a believer in doing it all the right way. Even doing the impeller and housing when its exposed. I think the leak is going to be fish line related tho. Another question: I heard ther is a devivice that goes on the prop shaft area that cuts the line before it wraps around?? Anyone have info on this??????Dave