yet another oil line cheak valve thread.

[jammin777]

hey guys after reading 68Ragtop's thread on this subject i've found i have the same issue with one of mine (787 rfi)
today messing with my engine, i decided to hook a hose to my check valves on the rotory cover, one of which i can easily blow air through it (by mouth) and the other the not at all but can with a little compressed air. the bad one tells me that oil can leak right on through while sitting. am i right on being concerned? also how much psi to be able to blow past the check valve? how much pressure does the oil pump produce to the little lines that go to the rotory cover? and finally, will the part numbers that 68ragtop posted work on my 787? 420956510
thanks 68ragtop for the tool idea as it looks like i'm going to have to make one myself.
PS. should i use a sealer if i replace? and what kind?

 

[68ragtop]

I looked in the on-line parts fiche and couldn't find the check valves for a 99 800 RFI.

is this the same as yours?
http://www.ebay.com/itm/Seadoo-GTX-..._Watercraft_Parts&hash=item46189c2299&vxp=mtr

Sure looks like the exact same part my DI uses. Out of the three my engine has, the only good one was the one in the air pump case. I didn't write it down, but I think it held between 1-2 lbs & let go around 2ish. My new valves will be in today, I will test them & let you know what new ones hold. My bad ones let go at less than 1 lb, & didn't hold pressure at all. Just leaked out.

 

[jammin777]

yep that is what mine looks like, one of mine doesn't hold pressure at all and i know it would just pour right through. the other i will have to pressure ck it. but if you would ck your new ones and let me know, that would be great to know what the new ones pop off at. i'm so glad you decided to ck yours out as your thread has info that explains another reason why the crankcase fills with oil other than the seals.
thanks for replying and taking he time.

btw i found one on ebay according to the part# you provided and looks just like mine.

 

[68ragtop]

Sorry for the delay.

I tested them & the new check valves release pressure around 3lbs. one was just over 3, the other two valves were just a fuzz under.
I then added injection oil to "wet test" them & had with the same result. they will hold 2.5 lbs for what would seem indefinite, & this was also true with vacuum. Bubble tested them, & no leaks whatsoever at 2.5lbs

So Then, I tested what was my only "good" original valve in the air pump portion of my engine & it released pressure at just under 1.75 lbs, & would only hold 1lb of pressure without leaking down. As you know the other two I already pulled released almost right away & leaked with any amount of pressure. they were shot.

So, while the last valve on my engine was working & not leaking, It was what I would call 50% strength of new.

I think its safe to say the valves do slowly wear out & should not be overlooked, But I suppose that makes sense as they are always exposed to crank case pressure & vacuum at the same rate as the RPM of the engine. I also think the 951DI has a disadvantage as the check valves are exposed directly in the case, where all the rest are behind the RV, or reed valves. But those are still are exposed to the pulses, just not as strong.

Guessing in most cases these leaking valves would go unnoticed as oil doesn't gravity feed through the pump at an alarming rate. But its still steady oil flow, & depending on how long the ski sits, who knows?

68RT

 

[jammin777]

68Ragtop, thanks for the very helpful info! the next question is do they fit? looks like i will replace both of mine, better now while the engine is out. i may be able to use a small punch and hammer mine out as mine are in the rotory intake. thanks again bro.

ps make me wonder why seadoo doesn't have a part #

 

[68ragtop]

Glad to help!

Yes, my replacement parts are identical. You might want to call your local seadoo parts guys.
I am pretty sure the dealerships see a little different fische than what is available to us.
I ran into that for some part i needed for my 4tec.

But, From the looks of the RFI valve i saw on ebay, it would appear to be exactly the same as what I have.

 

[jammin777]

i can confirm that the part no that 68Ragtop provided 42095610 is the exact same part no as a 99 rfi and probably the same for all!
here's where i found it. it's part no 27 on the microfiche.
http://fiche.seadoowarehouse.com/se...wc&a=207&b=2&c=0&d=-CRANKCASE-W/-ROTARY-VALVE

 

[68ragtop]

Just thought I would give a 4 week update.
I went out in the shop this morning, where I still have a pressure gauge on one of the replacement check valves. Still had nearly 1lb of pressure held on the gauge. Kinda forgot I even had it still on there & that slight pressure loss over 4 weeks probably came from my inline ball valve for testing. So, this would confirm that the check valves (when new at least), should not leak at all under low pressure. Obviously this resistance to pressure is what keeps oil from gravity bleeding into the engines during stored times. the pump itself has no ability to prevent gravity bleeding on this 951, & this is probably true on most injection pumps but I can't confirm that.....

 

[jammin777]

thanks for the update! may kinda sound weird but kinda glad you found yours was bad (sorry, double edge sword) which lead me to ck mine.
but not to say that i would doubt bottom end seals could cause a leak and fill the crank case, but my advise to those that are having internal oil leak issues is to check the oil line check valves first as it just may save from having to rebuild the bottom end.
the cheaper and easier process of elimination at the very least.