Broken Intermediate Suspension Fork-gctid398718

[Guest]

Returning from Deer Harbor in the San Juan's I hit a submerged rock ledge yesterday entering the wrong side of Blind Harbor(no pun intended) on Shaw Island. Only enter the bay from the left side channel keeping Blind Island on your Starboard side...the channel with a sign warning of dangerous rocks is the correct channel....the other channel on the west side of Blind Island with no warning sign or channel markers is the wrong one which I took.Other than a damaged prop I thought all was ok. I was moving about 2 kph when I hit the ledge. Only the drive and not the hull made contact. At 2,000 rpm the drive system was pretty smooth so we headed back towards Bellingham.

Just as I was halfway across Bellingham Bay the steering became noticeably stiffer and I couldn't keep the boat trimmed for straight direction for long without constant adjustment. The pics show why.

So my question is:

1) Will any 280 VP intermediate unit regardless of ratio/v8-4cyl fit my v8 ratioed drive?

BTW... don't enter an unfamiliar area near shore in the San Juans without your chartplotter or current chart in front of you showing what is in front of you lurking below the water.

Attached files [img]/media/kunena/attachments/vb/702406=29511-CIMG0035.JPG[/img] [img]/media/kunena/attachments/vb/702406=29510-CIMG0036.JPG[/img]

[Guest]

That sucks. I haven't been in Blind Bay, yet, but looking at the map you're saying only enter/exit east of Blind Island?

How deep was the water and how far were you from land?

[2850Bounty]

kalsobrook wrote:


So my question is:

1) Will any 280 VP intermediate unit regardless of ratio/v8-4cyl fit my v8 ratioed drive?

Short answer..... Yes! And this would include a 270, 275, 280 and 285.

If you swap out a complete Intermediate housing for another, and yet use your transmission and lower units, you MUST take the dimensions and re-shim.... no If's, And's or But's about it.

If all you broke was the suspension fork, why not install a good used suspension fork and reuse your existing Intermediate?

No re-shimming required! You've got to pull the transmission and lower unit anyway.

If you've not done this, or if you're not up for the task....., you're only a few hours north of me.

Wrap it up and ship it down here.

UPS is lightening fast between Portland and Seattle.

.

.

[Guest]

Good point Rick. I haven't looked at the Reverse Assy yet but am surprised it didn't release preventing this damage. I don't have a problem with the drive kicking up in reverse either.

[Guest]

On the off chance Rick does not have a fork for you, i have one for sale... and a boat with a hole in it.

[2850Bounty]

Some sellers call these yokes, forks, H-brackets, etc, and some will not know the difference between the 250 and later suspension forks.

http://www.ebay.com/itm/Volvo-Penta-270-280-suspension-fork-water-tube-/290738163932?hash=item43b15850dc&item=290738163932&pt=Boat_Parts_Accessories_Gear&vxp=mtr

http://www.ebay.com/itm/Volvo-Penta-Aq-280-suspension-fork-water-pipe-AQ270-275-280-/180920025036?hash=item2a1fac7fcc&item=180920025036&pt=Boat_Parts_Accessories_Gear&vxp=mtr

[Guest]

green650 wrote:
That sucks. I haven't been in Blind Bay, yet, but looking at the map you're saying only enter/exit east of Blind Island?

How deep was the water and how far were you from land?

Blind Island is a small Island you have to pass by to enter Blind Bay. It sits at the middle entry of the Bay. Always keep it on your Starboard side when entering. The water depth was around 30 feet just before I ran into the ledge. On the correct side the water level ia 30+ as long as you stay away from the warning signs for "dangerous rocks".

There are no entry markers on either side of the island to help with entering the Bay safely.

[2850Bounty]

Let's go her done and get you back on the water! Pick up a good used suspension fork, and I'll walk you through the process.

FYI: the 250 suspension fork will work, but these have brass threaded inserts in the vertical sections that may cause them to be not quite as strong as the 270 and later..... IMO that is!

Attached files [img]/media/kunena/attachments/vb/702633=29533-Suspension fork 250.jpg[/img]

[Guest]

Looking at the tweak in the uper part of the suspension fork the pivot tube might be damaged, and it's very important for the raw water circuit that this is in nice shape and seals good against the water neck gasket.

Those entrances look pretty sketchy on the chart, I would have a hard time picking which side to go on having the chart to work with, it would certainly be suicide without one.

You must have gotten the shoal that protrudes out from the main island in the west passage about 1 fathom deep in otherwise 4 fathoms of water, futher inward past blind island?

It's 1 fathom on the west side and there is a foul mark on the right side, pretty nasty there and a narrow channel to navigate if you were to cut east after passing blind island.

IMO, if I was traveling anywhere new out here and my chartplotter didn't work I'd put the boat back on the trailer and go home....if I hadn't researched my route ahead of time and didn't have a paper chart. There are some boating puget sound books that describe the nuances of most of the channels harbors and danger spots that are worth reading and even keeping on board.

[Guest]

Btw I live just out of Bellingham maybe 20 minutes and have the parts you'll need, whole drive or just the bracket and intermediate housing...I have 4 drives in various condition from a pile of parts to ready to go.

Will give you a good deal and you can touch and feel before you buy and no shipping

[Guest]

I now have a useable fork/intermediate unit to replace the broken fork and badly corroded intermediate housing on my existing 280 leg(didn't realize how corroded the bottom neck was on my existing housing until I got a close look at it).

I am just now going out to purchase some "bread sticks" to use as punches to drive out the bushing pins after I heat up the transom shield bosses. Hopefully they won't be too difficult to drive out. Trans is removed and the drive is ready to be pulled out except for the bushing pins.

I also found milky oil when removing the transmission so I need to figure out what needs resealed. Last season I put in new seals in the shift mechanism housing so water is probably not coming in from there.

I didn't change out the crosses when I installed new PDS seals and bearings so I want to do that now in addition to the fork replacement.

I know to be very careful and use heat to get the bearing box/clamping ring bolts loose and I guess I will need the 2 orings and a sealing ring to seal everything back up in the housing.

I did notice the reverse latching mechanism on the new intermediate housing is different than my existing one in that it only has one center spring versus 2 on the side. Will this be a problem or should I swap them. Since my reverse latch didn't seem to prevent the fork breaking after impact I am reluctant to want to use it again.

So...after doing this work will I need to recalc and reshim the intermediate housing/lower unit before reassembly?

Attached files [img]/media/kunena/attachments/vb/702780=29586-CIMG0037.JPG[/img]

[Guest]

rkcarguy wrote:
Looking at the tweak in the uper part of the suspension fork the pivot tube might be damaged, and it's very important for the raw water circuit that this is in nice shape and seals good against the water neck gasket.

Those entrances look pretty sketchy on the chart, I would have a hard time picking which side to go on having the chart to work with, it would certainly be suicide without one.

You must have gotten the shoal that protrudes out from the main island in the west passage about 1 fathom deep in otherwise 4 fathoms of water, futher inward past blind island?

It's 1 fathom on the west side and there is a foul mark on the right side, pretty nasty there and a narrow channel to navigate if you were to cut east after passing blind island.

IMO, if I was traveling anywhere new out here and my chartplotter didn't work I'd put the boat back on the trailer and go home....if I hadn't researched my route ahead of time and didn't have a paper chart. There are some boating puget sound books that describe the nuances of most of the channels harbors and danger spots that are worth reading and even keeping on board.

Ryan, thanks for the offer on parts/drives. I found a drive with a good fork and tube and housing so I am ok for now.

As for the navigation part my laptop/chartplotter had just shut down before I was near Shaw Island and I was using my Fishfinder GPS which doesn't have near enough detail to attempt what I unfortunately did. I really couldn't pack it up on the trailer then because we were about 25 miles or so from home. Good point though. The San Juans really require that you know exactly where you are are due to all the rocks and other hazards out there.I did get the laptop back up and functioning properly but as you advised....a good book perhaps or chart would have been prudent.

I sure love exploring out there though. A busted drive is a small price to pay for all the eye candy out there.

[Guest]

If you will use the new intermediate housing, you will have to recalc and reshim both sides.

IIRC, you want .0005 to .0015 clearance on the timken in the lower, and .001-.0025 compression(so it clamps the outter race) on the standard bearing in the upper case. Everything needs to be scraped clean of any sealer, corrosion, and be nice and smooth like a gasket surface.

Make sure you use the matching outer bearing race from whatever bearing you use in the lower unit. I.E, if you use the new intermediate, swap the outer bearing race from the old one into the new one and recalc shims. Take your time and measure about a dozen times, then assemble and see how it feels when you turn the vertical shaft. This one needs to be perfect!

I had a laptop nav setup to begin with and for anything but yachts they are no good. The chop bangs them around too much and makes them restart or crap out altogether.

[Guest]

Any advice on getting the last 2 longer of the top 3 screws out of the intermediate unit without distorting the cap heads? I have a heater blowing on the lower unit now but so far that hasn't helped. I can see the head on the screw starting to distort/round off and don't want that to happen.

[2850Bounty]

Ken, Ryan is correct. If you are using the new Intermediate housing, you cannot install your transmission or lower unit without going through the shimming procedure. That will lead to failure eventually.

The shims underneath the transmission need to offer a squeeze of approx .003".

IMO, .0005 to .0015 is not enough.

The pre-load or squeeze is to prevent the angular contact bearing from spinning in the case.

Easiest method, is to over-shim randomly, re-install the transmission minus O-rings, and fasten down just gently but firmly.

Take feeler gauge readings around the gap between the two cases.

Subtract a dimension from the "over-shimmed" pack that gives you this .003" when re-assembled and tight.

Re-calculate the shim pack, install shims, bolt the transmission in place with the O-rings this time.

Done.

For the lower unit, you'll need to see the Volvo Penta work shop manual for the A and B dimensions.

The instructions may be in metric, but you can use inches via decimal points.

The trick is in securing the race onto the roller cage while you take the A dimension. Without the Volvo Penta tool, you should take at least 6 to 8 readings before deciding upon one.

Gently tap the vertical shaft and the race downwards prior.

For the s/p lower, this is a negative pre-load for this bearing. The specs will be in this manual.

Yes.... use the race that was originally with the lower unit that will be re-used.

We don't mix races/roller cages.

When you remove the race from the old Intermediate, you'll find shims above it that you may be able to use.

Post photos of this reverse latch unit so that I can see what you are talking about.

All of these use a single center lift spring, and two outside over-centering springs, so I'm at a loss as to what you are refering to.

There is one additional coil spring, but this is for the lock brace!

Your latch unit should look like this one.

.

Attached files [img]/media/kunena/attachments/vb/703047=29616-Rev Latch unit.jpg[/img]