Volvo Penta 280 crack in suspension fork-gctid817164

[sandt]

The closer I look at things, the more discouraged I get. I am getting ready to replace the water neck fitting (aka hose connector) on my Penta 280 outdrive, and I was just looking at one of the pictures I took and noticed a crack in the suspension fork. See the picture below. Looks like it's cracked all the way through, though I dont have the boat here to check the inside. I am wondering how bad this is to drive with it cracked like this.. Im also wondering if as soon as I pull out the bolts holding the water neck fitting, the suspension fork is going to give way and the entire outdrive is going to try to drop... Does anyone have any idea how much stress is actually on that part, and what the possibilities are if I leave it? I assume to change it I have to pull the whole outdrive, but I havent really looked...


Attached files

[2850Bounty]

"sandt" post=817164 wrote:
The closer I look at things, the more discouraged I get. I am getting ready to replace the water neck fitting (aka hose connector) on my Penta 280 out drive, and I was just looking at one of the pictures I took and noticed a crack in the suspension fork. See the picture below. Looks like it's cracked all the way through, though I dont have the boat here to check the inside. I am wondering how bad this is to drive with it cracked like this..

[color]blue wrote:
My advice would be to not operate this system until the suspension fork has been replaced.

If it was to further break while operating it....... the repair costs may triple!

Remove the transmission, remove the lower gear unit.

Next, use heat on the transom shield's suspension fork "hinge pin" bosses, and carefully remove the two "hinge pins".

NOTE: the hinge pins are soft, so be careful and drive them out using nothing harder than an Italian Bread Stick. A brass or bronze drift punch works well!

Once this section has been removed and is on the work bench........, gently press the "pivot tube" out the bottom! Again.... a brass or bronze tool works best.

Keep track of the 1 SS washer and 2 plastic washers.

[/color]

[attachment]39057 wrote:
Suspension fork hinge pin removal.jpg[/attachment]

Im also wondering if as soon as I pull out the bolts holding the water neck fitting, the suspension fork is going to give way and the entire outdrive is going to try to drop...

[color]blue wrote:
NO..... it will not![/color]

Does anyone have any idea how much stress is actually on that part,

[color]blue wrote:
Yes..... a tremendous amount of stress and torque.

All of the propeller thrust is transferred through the suspension fork to the transom shield.[/color]

and what the possibilities are if I leave it?

[color]blue wrote:
1..... the crack may cause a seawater suction breach........ which may cause engine over-heating.

2..... if it was to snap completely in two, the damage repair costs may triple.[/color]

I assume to change it I have to pull the whole out drive, but I haven't really looked..

[color]blue wrote:
Yes..... transmission first....... lower gear unit next...... suspension fork/Intermediate last.

If all goes well, you can have it all back together in several hours.

NOTE: both the top and bottom areas of the pivot tube have critical surfaces and profiles. the pivot tube material is rather soft..... so be careful and gentle as you remove it. [/color] .

[color]blue wrote:
DO NOT attempt to TIG weld it...... this is in an area where the stress/torque is too great.

Here is one on e-Bay right now.[/color]

http://www.ebay.com/itm/Volvo-Penta-270-275-280-Suspension-fork-new-bushing-839457-875365-876168-/302381698853?epid=658477642&hash=item46675a8f25:g:eusAAOSwWxNYsf2n&vxp=mtr

[color]blue wrote:
Also..... use caution when doing an e-Bay search..... not all sellers know what they have, and often make mistakes when identifying an item.

I saw several mistakes while doing a search just now.

Suspension fork candidates are: 270, 280, 285 and 275.

Although it will fit....., DO NOT use a 250 suspension fork.

And..... if you should replace the Intermediate housing/suspension fork with another unit........... please note that re-shimming the transmission and the lower gear unit to this new housing is mandatory![/color]

. .


Attached files

[sandt]

Rick, is there any way that I can call to ask a couple of questions?

1 - looking at the workshop manual, it actually looks like I can remove the entire outdrive, without separating upper from intermediate, and this will get me to the top of the fork free. In the exploded diagrams, I dont even see anything that appears to be attaching the bottom of the fork to the lower gear unit, and in pictures it's hard to tell. I assume the water has to get from the intake to the hose so they HAVE to be connected somehow. Is it possible (though heavy), to just remove the entire outdrive as one piece without separating the different housings, and pull the fork off to replace it?

2 - If i have to remove the lower gear unit, do you know what parts I need? is it just the O-ring at the top of the countershaft (48 O-ring 925256)? Does the countershaft and gears have to come out?

3 - you said "Next, use heat on the transom shield's suspension fork "hinge pin" bosses, and carefully remove the two "hinge pins"."... Are the hinge pin bosses the the things with the red arrows in your post?

4 - is the ""pivot tube" " you mention the vertical tube that runs from the bottom of water neck fitting to the bottom/center of the suspension fork?

5 - you said "if you should replace the Intermediate housing/suspension fork with another unit........... please note that re-shimming the transmission and the lower gear unit to this new housing is mandatory!" Did you mean if I replace BOTH the intermediate housing and the suspension fork, If I only replace the suspension fork, it looks like this doesnt affect the gears by itself, so no reshimming, right?