dpsm outdrive holds pressure after seal repair but not vacuum.

[pae0332]

i have this drive from a 1998 v/p and the outer prop seals were leaking. i made the repair but it wont hold a vacuum of 15in, it drops to about 11 or 12. the book says to apply heavy oil to find the source.
has anyone done this that can walk me through it. i am not familiar with this process. .
thanks for any help

 

[alldodge]

15in of vacuum is a bunch, 5in is good enough

 

[Scott Danforth]

does it instantly drop? or slowly drop? what is it after an hour?

are you turning the shafts as you are testing?

if it slowly drops to the 11 or 12 overnight, thats fine. if it drops to zero, you sill have a seal leak.

 

[pae0332]

i pull the vacuum and turn the shaft bit in fwd , N & rev. then let is sit., it drops overnight,
right now i am testing it @ 10in. it has dropped 1in in 15 minutes,

 

[pae0332]

does it instantly drop? or slowly drop? what is it after an hour?

are you turning the shafts as you are testing?

if it slowly drops to the 11 or 12 overnight, thats fine. if it drops to zero, you sill have a seal leak.

any thoughts on this

 

[alldodge]

15in of vacuum is a bunch, 5in is good enough

i pull the vacuum and turn the shaft bit in fwd , N & rev. then let is sit., it drops overnight,
right now i am testing it @ 10in. it has dropped 1in in 15 minutes,

I would run it

 

[BRICH1260]

I would run it and check the oil again after a few outings. You may be ok.

 

[cyclops222]

Any seals that need to hold against ....Positive Pressure and Negative Pressure ( vacuum ). The seals MUST be placed in a certain way on the shaft.
I forgot the most important thing. The shaft bearings MUST NOT have any wear that allows shaft wiggle.

 

[pae0332]

question, when you install the prop shaft seals, do you typically grease the seal? i am thinking that the grease i put on the lips and inside the groove of the seal(were the spring rides) is causing the shaft to not get a good seal. and also , when i pul the vacuum, should i be rotating the shaft or let it be?

 

[alldodge]

I use gear lube but don't see an issue with grease

 

[cyclops222]

I always make sure the grease or oil is fully covering all the inside and outside of the seal surfaces. Same with the shaft surface. Wipe it all around any metal surfaces the the seal must slide on to get into the correct place.

 

[Scott Danforth]

, when i pul the vacuum, should i be rotating the shaft or let it be?

Manual states rotate the shaft

 

[Mc Tool]

I always put grease on a new seal , between the lips if it is either a double or triple lip seal.
Seals are like pump impellers in that it only takes a few seconds to wipe them out if they are run dry .

 

[pae0332]

well it has held a 6in vacuuum for 3 days now.

 

[Scott Danforth]

well it has held a 6in vacuuum for 3 days now.

install it and go boating

 

[cyclops222]

It could still not be LUBRICATED correctly. A 15 minutes of use and then a procedure ? Vacuum check is still required.

 

[2004 searay]

It could still not be LUBRICATED correctly. A 15 minutes of use and then a procedure ? Vacuum check is still required.

so your saying he should install the drive on the boat, fill it with fluid, run it for 15 minutes, drain it again and pull a vacuum?
did i correctly understand that?

 

[cyclops222]

Yes
Those seals do not normally give problems.