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A flywheel issue

I have not been able to find a factory made snap ring tool that will reach in to this deep area.
Also, a new non-Chinese bearing will run you about $15 only.
 
Rick: With some difficulty (someone replaced an inside snap ring that had a broken eyelet and yes I had to buy a super long pair of needle nose and modify with Dremel tool) I removed the seals and snap rings from both flywheel covers. For the old 318, the PDS (?) spindle fell out. Bearing appears to be good (it didn't come out but rotating it with finger it felt smooth and tight), spindle is not so good. Pitted. Removing the seal and snap rings from the 360 flywheel cover, neither the PDS spindle or bearing came loose. Are these pressed in? I presumed, probably incorrectly, if there were snap rings they were not pressed in. At this point it looks like pressing out the PDS spindle from 360 flywheel cover and putting it in the 318 flywheel cover. Am I correct? How does this come apart and go back together? Thanks so much. Looked for the search option you referred to but can't find where to get started. Nothing I could find in the banner menus.

Regular snap ring tool worked for spindle snap ring but I had to buy long needle nose and modify tips for the bearing snap ring.
 
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Rick: With some difficulty (someone replaced an inside snap ring that had a broken eyelet and yes I had to buy a super long pair of needle nose and modify with Dremel tool) I removed the seals and snap rings from both flywheel covers. For the old 318, the PDS (?) spindle fell out.
PDS = Primary Drive Shaft. (the "spindle" arm is the part that rotates the collar steering fork)

Bearing appears to be good (it didn't come out but rotating it with finger it felt smooth and tight), spindle is not so good. Pitted.
Do you mean that the PDS is not good?

Removing the seal and snap rings from the 360 flywheel cover, neither the PDS or bearing came loose. Are these pressed in?
The AFT PDS bearing will be a mild friction fit into the bore of the Flywheel Cover.
It should not require much force to remove it from the Flywheel Cover bore.
See *** below.


I presumed, probably incorrectly, if there were snap rings they were not pressed in.
The two larger snap rings expand and fit into a groove. One secures the bearing, and one stops the seal.

At this point it looks like pressing out the PDS spindle from 360 flywheel cover and putting it in the 318 flywheel cover. Am I correct? How does this come apart and go back together? Thanks so much. Looked for the search option you referred to but can't find where to get started. Nothing I could find in the banner menus.
You would need to search the Volvo Penta forum.

Regular snap ring tool worked for spindle snap ring but I had to buy long needle nose and modify tips for the bearing snap ring.
I think that you may be confused.
First you remove the AFT seal. Just punch a screwdriver into it and pry it out....... or run a sheet metal screw into it and pull on the screw head.
Next you will remove the two larger expansion snap rings.
***The PDS and the bearing will come out as an assembly. In other words, the PDS will be removed with the bearing still attached to it.
Once on the work bench, you will remove the small compression snap ring and then remove the bearing from the PDS.


Be sure to Pre-Fill the grease cavity prior to installing the AFT seal. Turn the PDS while adding grease.
We want the new grease to purge all air from the cavity, and we want to see that it made it's way through the ball cage.

By the way...... you won't know what size the FWD seal is until you get it out. It may also be a 35x62x7mm, but it may be smaller on the 62mm side.
 
Thanks. Sorry for the confusion. The snap rings came out okay (with difficulty). Once the snap rings were removed the PDS SHAFT fell out of the 318 flywheel cover. Apparently the play I noticed in that shaft when I did a comparative check of the two PDS seated in flywheel covers was not the 318 cover's PDS bearing but the shaft floating too freely inside it. That shaft is pitted and scored. Next step was removing the seal and snap rings for the 360 PDS. This was difficult because a broken head snap ring was replaced in it by somebody. I also noticed it has a sealed bearing even though the cover is fitted with a grease plug (318 PDS utilized an open bearing). Neither the PDS shaft nor its bearing will come out of the 360 housing. I have tapped on the end of both PDS shafts with hammer (+ block of wood to protect surface) in an attempt to shake the bearings loose. No luck. They are really stuck in there. The PDS shaft and bearing for 360 cover are both stuck in place. Given that this stuff is all supposed to be held in place with snap rings, I thought something was wrong. If I read you correctly I was right. Everything should have come out fairly easily. This morning I'll try heating the covers with propane torch and maybe I can get them expanded enough to release the bearings. If I can get everything out without damaging the bearings, I'll check the fit of 360 PDS shaft inside the 318 PDS bearing and if they mate up well, I'll use that bearing and that shaft inside the 318 flywheel cover. Given the amount of wear on the 318 PDS shaft I would be somewhat surprised if the bearing's shaft bearing face is not also worn. We'll see. If that bearing is not a glove-perfect fit to 360 PDS shaft, I'll buy another bearing. Even though the 360 sealed bearing is tight to 360 PDS, I won't use that bearing in 318 flywheel cover since it's obviously the wrong part for the job.

I wrote down the National # on the 318 seal before tossing it. That one was very stubborn but the seal for 360 almost fell out on its own. A very different looking seal. Dang it, the garbage was picked up today so they're gone. Once I have the bearing and shaft removed I can caliper those diameters and that should be enough to find a seal even if the National number can't be referenced.

I will definitely pack the cavity with grease when replacing the bearing and seal. I presume when doing maintenance through the grease nipple I'm supposed to remove the "out" plug on the opposite side of the flywheel cover so the seal isn't overly pressured? What type of grease? Regular wheel bearing grease would seem to be pretty stiff stuff to shove through a nipple. I always used regular chassis grease ... probably incorrectly.
 
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Thanks. Sorry for the confusion. The snap rings came out okay (with difficulty). Once the snap rings were removed the PDS SHAFT fell out of the 318 flywheel cover.
Again, PDS = Primary Drive SHAFT.
When we say "PDS", we are effectively saying Primary Drive Shaft! (I'm going to keep drilling you on these terms!) :D



Apparently the play I noticed in that shaft when I did a comparative check of the two PDS seated in flywheel covers was not the 318 cover's PDS bearing but the shaft floating too freely inside it. That shaft is pitted and scored. Next step was removing the seal and snap rings for the 360 PDS. This was difficult because a broken head snap ring was replaced in it by somebody. I also noticed it has a sealed bearing even though the cover is fitted with a grease plug (318 PDS utilized an open bearing).
Yes.... if the F/C offers a grease port/fitting, then you should use an Open bearing!
Otherwise, it becomes senseless to add any future grease to a sealed bearing.


Neither the PDS shaft nor its bearing will come out of the 360 housing. I have tapped on the end of both PDS shafts with hammer (+ block of wood to protect surface) in an attempt to shake the bearings loose. No luck. They are really stuck in there.
The PDS shaft and bearing for 360 cover are both stuck in place. Given that this stuff is all supposed to be held in place with snap rings, I thought something was wrong. If I read you correctly I was right. Everything should have come out fairly easily. This morning I'll try heating the covers with propane torch and maybe I can get them expanded enough to release the bearings. If I can get everything out without damaging the bearings, I'll check the fit of 360 PDS shaft inside the 318 PDS bearing and if they mate up well, I'll use that bearing and that shaft inside the 318 flywheel cover. Given the amount of wear on the 318 PDS shaft I would be somewhat surprised if the bearing's shaft bearing face is not also worn. We'll see. If that bearing is not a glove-perfect fit to 360 PDS shaft, I'll buy another bearing. Even though the 360 sealed bearing is tight to 360 PDS, I won't use that bearing in 318 flywheel cover since it's obviously the wrong part for the job.
Did you remove two (2) 62mm snap rings?
The deeper snap ring secures the bearing. (keep in mind that the bearing is already secured to the PDS via the small compression snap ring)
The outer snap ring simply provides a stop for the AFT seal to rest up against.

I wrote down the National # on the 318 seal before tossing it. That one was very stubborn but the seal for 360 almost fell out on its own. A very different looking seal. Dang it, the garbage was picked up today so they're gone. Once I have the bearing and shaft removed I can caliper those diameters and that should be enough to find a seal even if the National number can't be referenced.
Keep in mind that the AFT seal's ID will be 35mm. This seals against the universal drive shaft's female yoke...... not the PDS itself.
Some people get confused when they see that the seal is not touching the AFT end of the PDS. They see a large gap, and wonder what's wrong!


I will definitely pack the cavity with grease when replacing the bearing and seal.
No need to "pack" it... as in "packing bearings".
Let your grease gun fill it as you spin the PDS.


I presume when doing maintenance through the grease nipple I'm supposed to remove the "out" plug on the opposite side of the flywheel cover so the seal isn't overly pressured?
NO.... this is exactly why the AFT seal is to be installed in the Non-Conventional orientation.
Lip seals perform best when pressure is applied to the inner area of the lip. The more pressure, the greater the seal holds!
We DO NOT want this seal to perform in this way.
We WANT this seal to breach pressure!


What type of grease? Regular wheel bearing grease would seem to be pretty stiff stuff to shove through a nipple.
High pressure bearing grease works well. NOT the green Marine wheel bearing grease!

Also, remember to lube this bearing in the future (@ 40 or 50 hours), and do so with the engine at idle...... Dynamic -vs- Static lubrication!
With the cavity having been Pre-Filled, three or four pumps will do it.
 
Only two snap rings in each flywheel cover: one around the PDS and one compressed against side of housing ahead of bearing to hold it in place. No snap rings for seals. They apparently bottom against a groove in the housing. I understand about the gap in seal but good that you made sure of it anyway.

Bearings and PDS for both removed. PDS are different lengths so no swapping them. Anyway, it appears 318 PDS is fine. The slight pitting is not on the PDS to bearing surface but rather where the back seal on flywheel end is located. Not unexpected. Both bearing and PDS for 318 seem in excellent condition. Now I can't find any play in the fit. Wait ... let me go reverse the bearing and slip it over the PDF and see if that makes a difference ... not really. There is a very, very minuscule amount laterl play in the bearing itself and about as much in the shaft to bearing area. It's to be expected that the fit between shaft and bearing is not super tight (hence the snap rings instead of pressed on). I'll clean this bearing up and take it to parts house to compare to a new one. I suspect what I'm seeing is not anything to be concerned about. No grumbling in the bearing when I rotate it. Very smooth. I'm sure it's good. A lot of fuss for nothing it seems. Oh well. The tool place had a double pack of super long pliers (one straight tipped and one bent) for six bucks less than just the straight one alone so I got a good deal in the process.

Are the fiberglass exhaust elbows okay? If you approve, I'll order a couple 45 degree and fix up my old hose setup rather than the narrower Y-tube with exhaust relief plugged up that came with 360 engine. Go2Marine has those glass elbows on sale for a good price ($45 ea). I will keep the U risers on 360 even though the 318 didn't have them. Better safe than sorry.
 
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Exhaust elbows have been shipped and flywheel counterweight arrived yesterday. Now, another question. How much play is tolerable in the crankshaft bushing for PDS? There is about the same amount of play in both PDS ends when inserted into the crank. Not significantly sloppy but it's something. I'm guessing there is some allowance because the PDS does not rotate inside the bushing but rather rotates with it. Would appear to me that there's no way this bushing could have worn down from factory tolerances. The torque plate (or whatever it's called) that holds the PDS to the flywheel should provide most of the alignment to crankshaft anyway. The torque plate (?) from 360 is too wide for the smaller 318 flywheel I'll be using but it has extra bolt holes that will line up. A little bit of metal also needs to be turned out of centre of the 318 flywheel to allow the back side of 360 plate fit to it. Machine shop will fix both early next week. The 360 torque plate looks very good and clearly factory equipment matched to that engine (a Chrysler engine paint spot on both plate edge and flywheel to ensure realignment if/when removed) so I'll want to retain it.
 
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Only two snap rings in each flywheel cover: one around the PDS and one compressed against side of housing ahead of bearing to hold it in place.
There should be NO snap ring ahead of the AFT most PDS bearing. In other words, no snap ring in front of the rear PDS bearing.

A tip to help us communicate:
When discussing marine/boat parts, we should orient ourselves in terms of the hull.
If the bow is the front of the hull, then everything that faces towards the bow is forward or in front of.
For example: The PDS bearing will rest or stop against a shoulder within the flywheel cover's bore.
The snap ring will be AFT of the bearing (behind the bearing) so that it secures the bearing in the Flywheel Cover bore.
In other words, the snap ring is behind (or rear of) the bearing, not in front of it!



No snap rings for seals. They apparently bottom against a groove in the housing.
You mean that the AFT seal stops against a shoulder???
If so, this changes things. Either you will likely NOT have a 6206 bearing, or the AFT seal is of a larger OD.


I understand about the gap in seal but good that you made sure of it anyway.
Yes..... the seal will look as though it is not touching anything until the female yoke enters it.

Bearings and PDS for both removed. PDS are different lengths so no swapping them. Anyway, it appears 318 PDS is fine. The slight pitting is not on the PDS to bearing surface but rather where the back seal on flywheel end is located.
Did you mean the Front of the flywheel cover? (the end that faces towards the bow)

Not unexpected. Both bearing and PDS for 318 seem in excellent condition. Now I can't find any play in the fit. Wait ... let me go reverse the bearing and slip it over the PDF and see if that makes a difference ... not really. There is a very, very minuscule amount laterl play in the bearing itself and about as much in the shaft to bearing area. It's to be expected that the fit between shaft and bearing is not super tight (hence the snap rings instead of pressed on). I'll clean this bearing up and take it to parts house to compare to a new one.
Yes..... these are NOT expensive. Replace it with a good quality NON-Chinese bearing.

I suspect what I'm seeing is not anything to be concerned about. No grumbling in the bearing when I rotate it. Very smooth. I'm sure it's good. A lot of fuss for nothing it seems.
Again...... a bearing failure here can cause catastrophic damage. Please trust me on this.



Are the fiberglass exhaust elbows okay? If you approve, I'll order a couple 45 degree and fix up my old hose setup rather than the narrower Y-tube with exhaust relief plugged up that came with 360 engine. Go2Marine has those glass elbows on sale for a good price ($45 ea). I will keep the U risers on 360 even though the 318 didn't have them. Better safe than sorry.
I would not wish that old Chrysler exhaust system on anyone! The technology is far outdated.

Exhaust elbows have been shipped and flywheel counterweight arrived yesterday. Now, another question. How much play is tolerable in the crankshaft bushing for PDS?
Unlike a car/truck with a standard transmission, the PDS pilot nose does not rotate within this crankshaft bushing.
Still, it must be a good snug fit.



There is about the same amount of play in both PDS ends when inserted into the crank. Not significantly sloppy but it's something. I'm guessing there is some allowance because the PDS does not rotate inside the bushing but rather rotates with it.
Correct!

Would appear to me that there's no way this bushing could have worn down from factory tolerances. The torque plate (or whatever it's called)
That would be your Borg Warner drive coupler.
Borg Warner drive coupler .jpg


that holds the PDS to the flywheel should provide most of the alignment to crankshaft anyway.
No..... incorrect! The bushing is there to remove the centering load from the BW drive coupler.
In other words, we want the bushing to center the PDS pilot nose...... not the drive coupler!
If we relied on the drive coupler to center the pilot nose, any PDS oscillation would eventually destroy the center spring damping section!




The torque plate (?)
Borg Warner drive coupler!


from 360 is too wide for the smaller 318 flywheel I'll be using but it has extra bolt holes that will line up.
Yes.... the Borg Warner drive coupler offers a multiple bolt hole pattern for this reason.

A little bit of metal also needs to be turned out of centre of the 318 flywheel to allow the back side of 360 plate fit to it. Machine shop will fix both early next week.
The female bolt threads within the flywheel will be stepped and will be equipped with a shoulder alignment area.
You will be using ONLY Grade #8 shouldered bolts.
shouldered bolts.jpg
These shouldered bolts ensure proper
Borg Warner drive coupler alignment. (they do the same with an automotive clutch pressure plate)
You can space the drive coupler from the flywheel face by using SAE Grade #8 washers of the same thickness.
In other words, there may be no need to cut the flywheel if the SAE grade #8 washers
will hold it from the face enough!



.
 
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Thanks, Rick. I will use the same bolts that were on the 360 flywheel. I believe they have shoulders but I'll check to be sure. Yes, the seal does bottom against a shoulder. It's pressed in. The bearing will have to be pressed in too. Just too tight.

I'll see about getting a new bearing.

That's a good suggestion about maybe slipping washers behind the drive coupler. But the machinist will have to trim down the drive coupler edge anyway as the ears are too long (fits the larger 360 flywheel). He can lathe out a little metal in the flywheel centre easy enough to allow the drive coupler to fit flush against the flywheel. Won't hurt anything as there is lots of metal in that flywheel.
 
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Thanks, Rick. I will use the same bolts that were on the 360 flywheel.
As long as they are Grade #8 and have the non-threaded area (smooth shank) for alignment, you will be OK.

I believe they have shoulders but I'll check to be sure.
My apologies....... earlier I called these a shouldered bolt. They are actually an exposed shank bolt.

Yes, the seal does bottom against a shoulder. It's pressed in.

The bearing will have to be pressed in too. Just too tight.
Look to see if any corrosion is preventing it from sliding in with just mild force.
By the way...... you will be installing the PDS with the bearing already installed on it.
Alignment is rather critical. If not aligned, it may not slide in easily.

Volvo Penta PDS bearing install sequence.jpg

I'll see about getting a new bearing.
Since the AFT seal is stopped against an aluminum shoulder (as apposed to a snap ring), I'm going to guess that the bearing will not be a 6206.
The industry standard # will be on the original bearing.
None-the-less, I would certainly replace it with new.

That's a good suggestion about maybe slipping washers behind the drive coupler.
As long as they are equal in thickness.

But the machinist will have to trim down the drive coupler edge anyway as the ears are too long (fits the larger 360 flywheel).
I would be reluctant to remove any material from the Borg Warner drive coupler!
Please explain. Pictures would be helpful.



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No photos are necessary. The drive coupler on the 360 was designed for a "normal" size flywheel (134-160 tooth) but this 318 flywheel is only 122 tooth, an unusually small diameter, therefore the three ears on the "standard" 360 drive coupler extend into the tooth area of the 318 flywheel. Starter might not engage the teeth unless each of the three drive couplers' ears are trimmed. The machinist will do this on a lathe so the coupler remains relatively balanced. Trimming will not affect the bolt holes needed for 318 (although the coupler would never be useful again for an oversize 160 tooth flywheel as those bolt holes will be cut away).
 
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