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roblock
07-11-2012, 09:07 PM
Ok Steve (aka. veteran VJB Panther guru) when I had the engine out and changed the front oil seal, there was no play in the shaft of the jet. No lateral movement and no end play. The exit housing was on at the time.

While trying figure out why my seal came out last week, I took the exit housing off to see if I could learn anything. I was thinking at the time that maybe the bearings were goin out, overheated to some degree and blew the seal. I had already eliminated the water seal possibility because there was no water in the oil and the vents were not plugged up. All ended well and we determined the seal just came out from being slightly smaller in diameter than the original and devised the same fix as you shared.

But one thing is nagging me... with the exit housing off, there was significant end play. I could push the shaft forward and back, look over the transom and see it moving in and out of the slip yoke. I would say about 1/8 to 3/16" of play.

Is that because the exit housing was off?
Does the exit housing diminish end play in the same way it obviously supports laterally?
OR... do I have a bearing issue?

If it helps, I started the season with totally fresh oil after changing the seal. I don't know the hours, but I've burned less than 100 gallons of fuel thus far and the oil has changed slightly to a greyish green with perceptible but not an unusual amount of tiny metal flake for any normal gearbox or rear end.

ps. I am counting on hearing what you know I want to hear buddy :biggrin:

"THE ADVOCATE"
07-11-2012, 09:18 PM
She is a vintage jet boat?

roblock
07-11-2012, 09:43 PM
She is a vintage jet boat?

:4_1_72:

No... what I want to hear is more of :rooster: and less of :41616-4:

I want to hear that my end play is well within specs with the exit housing removed :smile:

78_Tahiti
07-12-2012, 01:36 AM
Rob, as much as I would like to tell you, what you "want to hear" I'll tell you what is most likely! There are only 3 things that can cause the shaft to move forwards & backwards on a Panther. 1) the 4, 3/8" bolts that hold the bearing set in the housing, are very loose. This is at the front of the pump. 2) The locknut that holds the tapered bearings & spacer together, has come loose. 3) The tapered bearings have worn, as well as the races, and now have unacceptable play, which can come apart pretty quickly. My guess is the lock nut, that holds the bearing pack, has come loose. This would also explain, the front oil seal, popping out of the bearing retainer. This locknut uses a toothed washer, with a number of tabs, that are bent over the appropriate groove in the locknut to keep it from loosening. Much like the front wheel bearing on a 4X4 Does. All these things require the removal of the pump. Which is not very hard to do. I remove the 2 bolts from the rear engine support (remove the bottom half circle mount) then lift the rear of the engine about an inch. Slip a small piece of 2X4 under the flexplate. Then remove the pump.

roblock
07-12-2012, 05:28 AM
So as I expected, the bearing assy is what locates the shaft for and aft..

The bolts are tight, so that's not it... the bearings are 33 years old, so its possible they need replacing... but the nut was something I had already mentioned here: http://www.vintagejetboats.com/showthread.php?3253-1979-Sandollar&p=56754&viewfull=1#post56754

Hmm... think I'll jack the engine forward by removing the half circle mount and two of the four forward bolts. I should be able to remove the bearing cap, get a look a the situation, tighten the nut if that is all it is, and get by. But... how do I know when the nut is tight?

Also Steve, if the nut still has its washer tab in place and the washer tab in the shaft is also in place, do I neccessarily needs to replace the bearings? Or, can I just take up the slack from years of wear?

78_Tahiti
07-12-2012, 02:34 PM
if the tab is still in place, pry it up out of the groove in the nut, with a small punch, like a nail set, see if you can get it a little tighter. then bend a different tab into the nut!

roblock
07-12-2012, 08:23 PM
Yeah... I think I will try and make it through the season. Talked to Tom at JBP today and I may even opt to send him the pump this winter for a rebuild. Not sure I want to tackle the bearings with my very limited tools.

My idea to rock the engine forward is lame. Looking at it at home tonight I'll just pull the engine. And I removed the exit housing again and took this little video. The movement was much less than I reported above. Now I am worried that the next tab on the nut may be too tight :biggrin:

http://www.youtube.com/watch?v=Es1nCa0zGcA&feature=youtu.be

78_Tahiti
07-13-2012, 01:50 AM
Thats not to bad Rob! I think all I would do, is suck the oil out of the resevoir, and use 85/140 gear oil, instead of 80/90. That will offer you a little more bearing protection. There is a bearing spacer between the outer races & there is a spacer between the inner bearings. So its not very likely you'll gain any improvement, trying to tighten the shaft nut. check the oil before every outing (or daily) and keep an eye on the seal, and I think you'll be fine for quite a while!

freudian Slip
07-13-2012, 05:56 AM
Sound's like with the right sucking and lube, you can work out the endplay. :biggrin:

Although I do find it a little disturbing you can remove your exit housing. Are you sure your doing it right? :4_6_2v:

You know they say a boat is just compensation.... How long have you had this fixation on endplay? Hmmm, maybe you should have a seat, and tell me about your parents.

Freud

roblock
07-13-2012, 06:07 AM
Hmmm... I didn't realize it was so serious Freud... my Mom did used to sing 'Tiny Bubbles' to me. :4_1_72:

roblock
07-13-2012, 06:12 AM
Thats not to bad Rob! I think all I would do, is suck the oil out of the resevoir, and use 85/140 gear oil, instead of 80/90. That will offer you a little more bearing protection. There is a bearing spacer between the outer races & there is a spacer between the inner bearings. So its not very likely you'll gain any improvement, trying to tighten the shaft nut. check the oil before every outing (or daily) and keep an eye on the seal, and I think you'll be fine for quite a while!

Sounds good to me Steve... think I'll do as you say for the bearings and also order a water seal and spare bronze nut for the impeller (just in case) and finish the season.

I was thinking that maybe the retaining washer failed and that the bearing nut was much looser than it really is. Worry is an old pastime of mine...

roblock
07-14-2012, 04:32 PM
Pulled the engine today, removed the bearing cap, and tightened the bearings. Also got that seal seated all the way down where it belongs...
5837

I had forgotten how many tabs the washer has. Overtightening was not a concern... I was suprised just how much I had to turn the nut in order to snug up such a small amount of slack. I just kept tapping it and checking it. I stopped as soon as I could feel no detectable movment forward and back. There was a tab right there to bend into one of the spots in the nut. Worked out great...

I also picked up a feeler gauge so I would know exactly what the clearance is between the impeller and housing. In the video I am using .020... For sure, ts somewhere between .020 &.025 and that makes me very happy considering its 33 years old.
http://www.youtube.com/watch?v=Pod6MnrPzKM&feature=youtu.be

Steve, I know your clearance is .10 with the bronze sleeve, but what was it from the factory?

78_Tahiti
07-16-2012, 11:23 AM
Yours is just like factory Rob! Stock is .025" to .030" and by the look of yours, there is absolutely NO Wear in your pump housing! They will groove the housing where the impeller rides. With the Aluminum/Bronze Sleeve, like mine, the clearance spec. is .010" to .012". Your pump is in pristine condition!

roblock
07-16-2012, 09:50 PM
Well on that count... its hard to get better news than that!:smile:


I figured it must not be too bad or else my rpms would be higher. But I am somewhat suprised considering the bearing wear.

This evening I got out and checked the axial fit according to the manual at page 4-8. It is supposed to be .020 - .030... Mine is over .030. I need to check it again, but it looks like I can shim it out according to the manual. Is that correct?

I have not measured the radial fit. The impeller looks fine, no wear is noticeable, but the stator rings show wear. The aluminum definitely gives way before the stainless. I can feel the wear with my fingernail. Like you said about the housing... the housing has no groove, but the stator does. Its a prety good amount of wear, but I don't have the proper tools to measure it. Any thoughts? Want pics?

78_Tahiti
07-17-2012, 12:53 AM
first off, the shaft has to be in a jig (or a lathe) to accurately check run-out. The rear DU bushing is what supports the shaft. the aluminum stator rings are supposed to track on the impeller slightly. The easiest way to tell if they are way out of spec. take a look at the bottom of the exit housing. There are 5 or 6 small holes drill through, behind the stator rings. If the rings are worn, you will see a lot of water spraying from these holes while running on plane. Not sure who your going to get to look over the back of the boat, while blazing along at 30 or 40, but, hey, thats part of the thrill of owning a Panther Jet!