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DP-D1 Shimming vertical shaft help

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mklarend

New member
Hi, folks
I'm new here and I have problem with vertical shaft shimming procedure according to OEM manual.
I recorded all shimms ticknesses and stampings at lower unit housing while disassembling.
For vertical shaft: 0.80mm shimms under vertical shaft bearing.
Pinion gear mark is +1 that is +0.01mm
H stamped is 99
According to OEM Manual:

H-nominally 277.00mm
H-stamped + 0.99mm

H=277.99mm

Pinion, nominally= 60.00mm
Pinion, stamped= +0.01mm
Pinion 60.01mm
Vertical shaft +217.75mm
277.76mm -this number must be larger than H and that is a reason why we must put shims under bearing, but in this(mine) case is not,
-277.99mm
-0.23mm minus value
But then, there were 0.80mm shims under vertical shaft. This was factory shimming.....
Only logical explanation is that nominally is 276.00 or 277.00. If I'm correct than OEM manuals from 285DP to DP-D are incorrect....
Please don't guess in your replays. In this thread we need Volvo Penta expert to give us answer.
Thanks
 
OK..... first off, I have quoted Bob from his similar thread...... as I have a few comments:

captbobs said:
Ricardo,

I do understand the relationship of the A - B dimension with regard to the vertical shaft. The preload pressure exerted by the shimming in the intermediate housing on the race of the tapered roller bearing prevents the drive gear from riding up,
Please understand that this is a "Negative" preload, of which can be confusing to some people.

but on the other hand, if the drive is in reverse, the gear would tend to pull the shaft down,
NOT so!
Regardless of force direction, Hypoid gears want to oppose one another when under load.

and the articulated ball bearing (this is an Angular Contact Bearing) is there to provide the opposing force in the pretensioning setup to prevent shaft movement in the downward direction. The pretensioning is created between these two bearings.
I may not be fully understanding Bob re; his above comment!


It is the shimming of that bearing that determines how far into the lower gear housing the drive gear extends, and consequently how much contact the gears make.
You would need to have Hypoid gear experience to understand the procedure!
However, it's my understanding that Bob's thread is inquiring about the lower-unit-to-Intermediate-housing shimming (as though changing one lower gear unit for another)..... yes/no?

So I go back to my original question? What do you do when the shop manual does not describe or even anticipate the possibility of a calculated negative value for those shims. That is why I said I see no other coarse but to put the original shims in and go through the end play, gear contact and pretensioning measurements listed in the manual.
First, make sure that you are using an OEM Volvo Penta work shop manual for your year/model stern drive, and NOT a Seloc or a Clymers!
Secondly, make sure that you are not becoming confused with lower unit gear set-up -vs- lower gear unit-to-Intermediate-housing shimming!

I do not have the factory tool. I considered buying it, but I have the intermediate housing which while it would be clumsy, it can be used in place of the factory tool to set the A - B shimming on the race to do the initial setup.
The factory tool (884348) is designed to hold the race down against the roller cage as to eliminate any up/down play while obtaining non-Intermediate housing shimming data. The A dimension becomes a factor re; the calculation as for above the bearing race shim value.

If I have to remove the race and change the shimming it can be done.
This race is typically removed for several reasons:
1...... so that the original lower unit race can be use with it's original roller cage....... or if a new race is being used.
2...... so that the above-the-race shim value can be changed!

Volvo Penta suggests a NEGATIVE pre-load of .002" (I have always shot for .001"), or a POSITIVE pre-load of NOT TO EXCEED .0008".


I have done those calculations with the intermediate housing, and B = 8.13mm and A = 7.72mm. This gives me 0.40mm after the 0.01mm for preload is deducted.

Capt Bob S
Click to expand...




mklarend said:
Hi, folks
I'm new here and I have problem with vertical shaft shimming procedure according to OEM manual.
Would you please clarify as to what you are attempting to accomplish?
............. are you attempting gear pattern set-up?
............. are you re-installing an original lower gear unit?
............. are you attempting to install a replacement lower gear unit onto an existing Intermediate housing?

I am reluctant to comment on your further questions until this is known.

I recorded all shimms ticknesses and stampings at lower unit housing while disassembling.
For vertical shaft: 0.80mm shimms under vertical shaft bearing.
Pinion gear mark is +1 that is +0.01mm
H stamped is 99
According to OEM Manual:

H-nominally 277.00mm
H-stamped + 0.99mm

H=277.99mm

Pinion, nominally= 60.00mm
Pinion, stamped= +0.01mm
Pinion 60.01mm
Vertical shaft +217.75mm
277.76mm -this number must be larger than H and that is a reason why we must put shims under bearing, but in this(mine) case is not,
-277.99mm
-0.23mm minus value
But then, there were 0.80mm shims under vertical shaft. This was factory shimming.....
Only logical explanation is that nominally is 276.00 or 277.00. If I'm correct than OEM manuals from 285DP to DP-D are incorrect....

The AQ series Duo Prop was introduced in 1983 as a 280 or 285 option.
Since then, the DP has undergone a few changes.
It would be very helpful if you were to post an exact year and drive model and perhaps a few photos.

Please don't guess in your replays. In this thread we need Volvo Penta expert to give us answer.
Mklarend, it would be foolish for any of us to offer you a "guess". A "guess" could cost you an expensive repair down the road!
For this reason, it is always best to use an OEM Work Shop manual, or to take your stern drive to a qualified and certified AQ series technician for this type of service work!


Thanks
Click to expand...
 
Just to be clear.......


If I have to remove the race and change the shimming it can be done.
This race is typically removed for several reasons:
1...... so that the original lower unit race can be use with it's original roller cage....... or if a new race is being used.
2...... so that the above-the-race shim value can be changed!

Volvo Penta suggests a NEGATIVE pre-load of .002" (I have always shot for .001"), or a POSITIVE pre-load of NOT TO EXCEED .0008".
This means .0008", or 8/10,000 of one inch!
Not 8/1,000 of one inch!

Click to expand...
 
Thanks for replay, Rick
I understand shimming between intermediate and lower gear, and only correct example and explanation of this shimming is older service manual with SP and DP drives in it 7731624-8 6/2003.
Max allowed clearance is 0.002''(0.05mm) and max allowed ''positive'' preload is 0.0008''(0.02mm)
Newer service manuals are incorrect about this shimming because in example bearing height above the lower unit parting plane “A'' have bigger value than ''B'' outer race hole depth in intermediate housing or tool in example.... In that case result is big positive preload, but they take that value as a clearance. They mixed up ''A'' and ''B'' value.
In service manual for DP-D, DP-D1, DP-D2 they want to achieve clearance of 0.0004''(0.01mm), for DP-G preload of 0.0008''(0.02mm)..... But I agree with you goal is to achieve minimum clearance of 0.001'' is just fine.
Pressure test of my drive give me a crack between oil and water inlet in a lower gear case. Outdrive was DP-C1. I get DP-D1 lower gear case, but full empty. All parts inside are the same. I check ALL internal part numbers in parts catalog for both outdrives lower gears.

First step was complete disassembly cracked, old DP-C1 lower gear with measuring shim ticknes under all bearing races of lover gear. This was for my training and to see factory shimming results. I take all gear markings and housing markings too G,H,F,C. Then I start to calculate shim thickness for this same DP-C1 cracked lower gear to compare my results with factory shimming. Factory pattern was perfect pattern.
DP-C1
''H'' marking is 99
I found 0.80mm under ball bearing of the vertical shaft
Pinion stamped +1
According to OEM manual:

H-nominally 277.00mm
H-stamped + 0.99mm
H=277.99mm

Pinion, nominally= 60.00mm
Pinion, stamped= +0.01mm
Pinion 60.01mm

Vertical shaft +217.75mm
277.76mm -this number must be larger than H and that is a reason why we must put shims under bearing, but in this(mine) case is not,
-277.99mm
-0.23mm negative value
This means that I don't need shims for vertical shaft and instead of shimming I must cut material under vertical shaft's ball bearing ??????????
This is my problem and Capt Bob S too.
So my question is: is there any possibility that H-nominally can be 276.00 in a case that H stamped is from 50 to 99 ?
In that case this calculation have sense and 0.80 mm shims too
Like G nominally (60.00 or 61.00) depends what value is G stamped when we calculating front bearing shims....

Thanks
 
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