I'm putting an M41 in my '68 144 instead of the 1970 M410 I was planning on using to replace the BW35. Project has been delayed way too long. The M41 seems the better of the two. THe M41 is ready to install. I have the flywheel, clutch, and bellhousing mounted already. I changed all the O rings in the J mated it to the M41. I started thinking about the front M41 seal prior to installing. I think I want to change it now.

From a parts breakdown it seems to show a seal, gasket and O-rings for the three housing bolts. Is that correct? Do you just pull the bolts and replace the seal, gasket and O rings? Any chance the front shaft will fall out in the process? While I'm at it how hard is it to change the front bearing. It seems quiet. Just leave it be?

The Haynes manuals suggests to install the tranny with the bellhousing attached. It says the allen bolts that hold the tranny to the bellhousing are hard to get at if you install the bellhousing by itself first. I'm not seeing it that way. The allen bolts don't seem like they will be all that hard to get at compared to the bellhousing bolts with theh tranny attached?

Craig

Stand the box on it's end for a few hours & see if any oil runs out of it.

If you are just removing the box & not looking at the clutch, then you can go ahead & use the allen head capscrews. Cut a small length off an allen key & use a ring spanner on it to loosen or do the final tightening on the allen heads.

Well.. I, for one, have *always* installed the transmission/bell housing as a unit in all old Volvos, with exception of those pesky B16 designed 544s. Lift and guide the bellhousing with your knees while lifting with hands the back. Keep in mind that's the only way to do it if you go with the M410, which.. is also a good bit heavier than a M41. Wear your grease clothes. The rope through the shifter hole with assistant inside is a great help if you have a '72 or later car (remote shifter)

Have the top starter bolt through the bell housing before you offer it up to the engine.. whichever way you do it.



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-Matt I ♥ my ♂

I've done both, but I reckon its much easier to first put on the bell housing and then fit the gearbox. When I'm working on my back under the car I stick the gearbox at an angle with the input shaft resting on the opening in the bell housing, then just lift it up, being careful not to dislodge the release bearing.

You da man Matt !! I would rather crawl in a 20 ft python den and wrassle it out than try and lift that Bellhousing/M41 under the car. The rope trick works well with my swan neck shifter on my 71 142E.



Joel
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Antique Swedish Steel 71 142E color V#102

For the heck of it, I tried to replace the transmission with the bell housing attached. Way to heavy and bulky. I'd like to meet the person that can lift an M41,bell housing and OD as a unit to the motor.

I ended using hex bolts to attach the tranny to bell housing over the years. On my 142 I like em better.

I used to hoist the M41 unit into the bell housing by hand. Testosterone levels drop after 30 years. Now I rig a rope to the tranny through the shifter hole and have my wife pull up while I stab the throw out bearing.

Joel
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Antique Swedish Steel 71 142E color V#102

The bearing retainer can be removed easily and the gasket and orings replaced. Installing the seal is best done with a socket that fits just inside the steel outer shell, and pressing it in with a vice.
The front bearing might be removed if you have the specialized puller that draws the inner race between the balls. I doubt you'll have that. Installing a new bearing will be impossible. If you allow the input shaft to slide forward while changing the seal on the bearing retainer a synchronizer shift plate may become dislodged, and you'll be dismantling the entire trans to assemble that one again.
Throw away the socket head bolts, get some 7/16 capscrews of the same length, and install the bell housing first, then the trans. Just why Volvo used those socket head bolts is a continuing mystery, and they are not needed.

Those allen bolts are much easier to get at than a hex bolt providing you use the right tool, my tool of choice is a ball headed allen key with a long extension. Simply reach over the top of the gearbox and out it comes.

What kind of wrench do you use on the 7/16" cap screws?
Hex size would be 5/8" or 11/16" (like the headbolts).
I'm not sure a box wrench that big will fit into the dimple in the side of the tranny.
I may try it next week when I re-tranny the yellow peril, who has a clanking and jumping reverse.
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George Downs, Bartlesville, Heart of the USA!

I use a 5/8 universal joint socket, Hazet or Snap-On. Easy.

Hello,

Have you ever removed or installed the upper transmission bolts on a 544/444?

That is why they are socket heads.

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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502

"From a parts breakdown it seems to show a seal, gasket and O-rings for the three housing bolts. Is that correct?"

Yes.

"Do you just pull the bolts and replace the seal, gasket and O rings?"

Yes.

"Any chance the front shaft will fall out in the process?"

No, but still be careful anyway.

"While I'm at it how hard is it to change the front bearing. It seems quiet. Just leave it be?"

Technically, you can change it without disassembling the gearbox, but it would be super difficult. Much easier to change when you have the gearbox apart. My opinion is if it is quiet and you have no reason to think it's bad, leave it.

I have never had a problem installing the bell housing first and then the gearbox to the bell housing. Of course this is referring to a M4, M40, M41. Actually, I don't think I've ever done it any other way.

My tools of choice for the transmission bolts is a short length of 3/8 hex bar (cut from an allen wrench) along with a 3/8 drive 3/8" universal socket. The loose length of bar can be inserted into the bolt head with a good length box end wrench on it. Crack the bolts loose (watch your knuckles). Unscrew with the universal socket and extension. Use the box wrench again to tighten these bolts. -- Dave

My tools of choice for the transmission bolts is a short length of 3/8 hex bar (cut from an allen wrench) along with a 3/8 drive 3/8" universal socket. The loose length of bar can be inserted into the bolt head with a good length box end wrench on it. Crack the bolts loose (watch your knuckles). Unscrew with the universal socket and extension. Use the box wrench again to tighten these bolts. -- Dave

I agree. I use a short piece of 3/8" alum wrench in a 3/8" socket and a 3/8"
drive extension.
That gives enough flexibility (with the tranny hanging down) to tighten it up fairly well.
Sometimes I finish the job with a regular alum wrench and a piece of 3/8" pipe or other suitable tube
as a cheater.
Do you think your front tranny seal is bad? Usually they last pretty well.
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George Downs, Bartlesville, Heart of the USA!

I don't know history of M41. I just thought while it was out why not change seal. I pretty much have gone over everything else including rear seal.

M41 seems real quiet turning even without oil in it. Maybe just let bearing be and change seal only.

Craig

That is what I would do.
I note others have chimed in with a similar method to mine.
For a while I had misplaced my short piece of alum wrench and had to cut another.
Now I have 2 and a short-handled alum wrench.
I suspect a long-enough and strong-enough 3/8" box wrench might be hard to find...
(Mine has a kink in it near the 3/8" end. Guess why!)
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George Downs, Bartlesville, Heart of the USA!