Jump to content

Neil's '41 Super Model 51


neil morse

Recommended Posts

Failure Mode

 

As has been explained earlier, it's pretty clear that the problem with my transmission was caused by a faulty installation that resulted in the throw-out bearing support snap ring getting caught up between the bell housing and the transmission where it proceeded to chew up the front bearing and get broken into three pieces.

 

Now that I've put the new support in place with the snap ring, a photo comparison shows more clearly than ever what happened.

 

Here's a pic of what it looks like now with everything seated properly.

 

spring_washer.thumb.jpg.7cc66b83b6c577d8f05667f121748d50.jpg

 

Compare this with what we found when we removed the transmission.  The impression in the RTV is like a fingerprint that shows that the snap ring was not seated correctly.  It was situated in the outer recess instead of the inner recess, and you can clearly see from the impression that the ring was not fully compressed.

 

engine_rear3.thumb.jpg.263bc4aedadbbe1825ab136c6e6ba37b.jpg

 

I love this -- kind of like a crime scene investigation!

  • Thanks 1
Link to comment
Share on other sites

2 hours ago, Ben Bruce aka First Born said:

When are you installing or is it done?  Finished assembling mine this evening. I finally determined the rear bearing was the culprit.

 

 

Hi Ben:

 

I'm glad to hear you found your problem.  We will be putting the transmission back in my car this coming Tuesday, the 25th. Watch this space.

  • Thanks 1
Link to comment
Share on other sites

I'm happy to report that we got the transmission back in the car this morning, and a shake-down cruise around the block revealed no problems.  I have yet to give it the "acid test" of coasting down a long downgrade in third gear, but I am pretty certain we took care of the problem of it popping out of gear.  I am extremely grateful to my friends Don, Konrad, and Tom for all the help and support!  What a great hobby!

 

Neil

  • Like 4
Link to comment
Share on other sites

Neil, I was surprissed at how fast we got her all assembled. Now that you have given her a shake down cruise, I think it might be a good idea to check the torque on the spring hold down plates. I suspect thing could settle (shift) as the springs find their new home. Remember lefty tighty!!!

 

Konrad

  • Like 1
Link to comment
Share on other sites

Thank you for that piece of advice, I will definitely check that.  And thanks for the reminder about the left-hand threads.  As I have said many times to my automotive mentors and teachers, don't ever hesitate to tell me something, even if it seems obvious! 😄

Link to comment
Share on other sites

It was you that told me about those pesky south paw threads. Even knowing that they were there, I had to be very cognizant of which way I needed to turn the fastener! I mention them as there was evidence that an earlier mechanic was not aware of these threads. 

 
Now that a few hours have past I’m a shamed to say I’m feeling the effect of the job. My arms are aching a bit. Not too surprising as the one issue we had, was that we failed to pull back the torque tube prior to stuffing the transmission into the transmission tunnel.  That left me hold up the transmission for a bit longer than I anticipated.:(
 
All in all it was an easy and safe repair. Heck, after cleaning up in a hot shower I found I didn’t even have any scraped knuckles.
  • Like 1
Link to comment
Share on other sites

Just to make this clear for anyone trying to follow along, the "southpaw" threads we are talking about are on the "keepers" that hold the coil springs onto the rear axle at the bottom of the coils.  The threads are left-handed on both sides (to compensate for the "twisting" movement of the springs when they contract).  On my car, we found that someone had apparently been unaware of this and had stripped out the threads on one side.  He had then drilled it out to a larger diameter and substituted a right-hand nut and bolt.  Don happened to have an extra "correct" left-hand keeper which he generously gave me, so my car is now back to the proper configuration.

 

With regard to Konrad's sore arms, I will soon be posting a wrap up on this job with an account of what we learned that may help other people in the future.  As I said at the beginning of the transmission job, I know that this may just be another day in the shop for many of you, but it never hurts to post what we've learned along the way that may be of some help to others.

  • Like 5
  • Thanks 1
Link to comment
Share on other sites

 Nice thread, and great instructions on overhauling these trannies.

Too bad I found out the hard way about those left hand threads when I took the rear springs off mine, when I took apart for the first time about 15 years ago.

Reading through this leads me to think my trans might need to come out again. I did replace the front bearing on mine, at the time, unless there is something else amiss. The popping out on mine isn't too bad, sometimes doesn't even happen, and its' the same as yours, a coast in third gear.

 However, being winter here in the Great White North, I'm having getting my fun by doing the Dynaflow on my son's '55 Special.

 Thank, Neil, and the rest for some great looking work. I also have to second Matt's comment a while ago, it is truly amazing that it suffered through all that abuse, poor lube or what caused the "coke" inside, without major parts being damaged, and is now ready to go again!

 Keith

  • Like 2
Link to comment
Share on other sites

Thank you, Keith.  I have a couple of thoughts.

 

First, with regard to your transmission, the main thing I learned from the experience of working on the transmission in my car is that the "pop out of third" problem can occur when the front bearing being free to move forward, even just a tiny bit.  It sounds like that could be what's happening in your car.  That front bearing is a slip fit, and unless everything is properly in place that holds the bearing in position, it can slide forward causing the inner dogs on the third gear (in the very front of the case) to slip out.  The bearing is normally held in place by the pressure from the throw-out bearing support pushing against it, with the large "snap ring" (really a spring washer) in between the throw-out bearing support and the front bearing.  As you know, on my car the snap ring had been destroyed and had damaged the ball carriage of the bearing and the oil slinger, so the bearing was free to move forward.  This was exacerbated  by the use of RTV instead of a gasket and the poor alignment between the transmission and the bell housing.   In a thread by @Nevadavic, Vic reports that the "pop out" problem on his '41 Roadmaster was caused by the fact that the snap ring was missing altogether.  So even though you replaced the front bearing, you may have a problem with what is supposed to be holding it in place.

 

Second, with regard to why my transmission parts survived so well despite the damaged bearing, what we actually found was that the bearing (although the ball carriage was damaged) was working fine.  I think the "poor lube" problem was pretty minor -- transmission oil was leaking out the front of the case and into the bell housing area because the oil slinger had been destroyed, but as long as the car wasn't driven very much and the oil was topped off periodically, I don't think it suffered too much.  And what Don originally thought was "coke" coating all the internal parts actually turned out to be more of a "varnish."  Although he had never seen that before, others have reported that it's not uncommon in old transmissions.  I don't know what causes it, but it may have to do with using the wrong kind of transmission oil.  So I don't think there was a significant overheating problem with my transmission.  So that's my little bit of "post-hoc" analysis now that we have completed the job.

 

Good luck with the Dynaflow -- that must be quite a job!

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

Neil, Tom and Konraad.

Congratulations.

 

I think you guys as sort of greenhorns did a great job of getting that job done.  I was especially impressed at how quickly you got it back together and on the road. (left handed threads aside).

 

Konrad, no bruises or scrapes?  My dad used to, tell me "if you didnt bleed on it, you didnt do a good job". I did my best to NOT follow that advise.

  • Like 1
  • Haha 3
Link to comment
Share on other sites

 NO JOB IS COMPLETE WITHOUT ITS POUND OF FLESH AND BLOOD. Or so I'm told.

 

I stopped by Neil's place just to make sure that there weren't any leaks or other disasters. Much to my horror I find Neil's feet sticking out from under the car (looking much like a scene from the Wizard of Oz, the one with the house on top of a Wicked Witch of the East). Well, he was just adjusting the hand brake. I can say there isn't a drop or even any signs of oil weeping from the gearbox. 

 

There was one issue I needed to take care of so that we wouldn't be accused of hot rodding or modifying the car. One of the cross member bolts had a USS threads when the other three were SAE threads. I took care of that oversight in 5 minutes. All 4 carriage bolts are now sporting SAE  threads. (looks much better)!

 

We took the car for a drive around the city. After getting her warmed up and running she is now running and shift like new. I'm always surprised that even with old well used machinery one needs to give things some time the break in ( find its new equilibrium). After all we have disturbed much and may have re-shimmed things. At the end of the drive Neil and the car had become one again.

  • Like 2
  • Haha 1
Link to comment
Share on other sites

Thanks for the report, Konrad!  I just logged into the forum to post this pic and my own report of the afternoon's events, but Konrad has summed it up so well I will just post the photo.  It looks like just another photo of my Buick in the driveway, but it's not.  It's a photo of my Buick in the driveway after a successful test drive during which I tried my best to get it to pop out of third gear and it just wouldn't do it! 😄 I'm a very happy camper and again want to thank my friends for all their help.

 

back_on_road.thumb.jpg.24d3fc4dacc27498c76f83983e5d6169.jpg

  • Like 7
Link to comment
Share on other sites

Since a Buick actually "pushes" the car via the torque tube, that mount and crossmember, the rod helps stabalize things by connecting the center od that crossmember directly to the frame.

I adjust it so, with the frame bolts just run up to contact, I take all the slack out of that rod and then tighten the crossmember.

  • Like 2
Link to comment
Share on other sites

Don, your procedure is consistent with the '41 manual which says "The rod running from frame X-member to support mounting should be adjusted so that no tension is placed on rod."   It also says (as the final step to adjusting all of the engine and transmission mounts), "Tighten rod in transmission support, being careful not to cause any 'push' or 'pull' tension in rod."

 

On my car, I took the rod off and cleaned up the threads once we had removed the cross-member so that it could be easily adjusted if we needed to.  When I put the rod back on the cross-member, I tried to put it right back where it had been.  Apparently, I was successful (and we didn't change things too much by installing the new front and rear transmission mounts) because when we put that cross-member support back in the car, the attachment hole at the rear of the rod lined up perfectly with the hole in the X-member and the rod could be reattached without putting any tension on it.  So I guess we didn't go exactly "by the book," but I think we ended up in the right place.

Link to comment
Share on other sites

5 hours ago, Konrad said:

Ref. the book Real Men Don't Eat Quiche. I think this came out in the 80's)

In the 1970s (I wuz dere) as a counterpoint to "Real Women Don't Pump Gas," from the days of the oil embargo, when serve-your-own-damself became the norm.  Ladies learned how to pump gas....

  • Like 1
  • Haha 1
Link to comment
Share on other sites

Plaid Tour

 

I attended a great local event today.  It was SUCH a pleasure to drive my car over 100 miles (including a lot of long downgrades) and not have to worry once about it popping out of third gear.  I am so used to anticipating it, that it's hard to believe that the problem has actually gone away!

 

My car was the only Buick in the crowd, but there were plenty of other nice cars there, to be sure.

 

Plaidtour2.thumb.jpg.b855c2a9cf2b9fcb30696f4ddb73ff0e.jpg

 

@Grimy (George) was there with his magnificent '34 Pierce Silver Arrow (not Grimy in the pic -- just a bystander).  I was fortunate enough to drive behind this car for a few miles and it looks even better in motion than it does standing still.  "Majestic" is the word that comes to mind.

 

Silverarrow3.thumb.jpg.63ec24a5336ceacf2b215562194764bf.jpg

 

Silverarrow_engine.thumb.jpg.a0920e3e3efec52f07a5d1862d2fa5d2.jpg

 

Silverarrow2.thumb.jpg.f7c1fd18c4e3fabd787db1bccae82aa8.jpg

 

Also present was this very nice '31 Plymouth PA sedan with great period "air conditioning."

 

31_Plymouth.jpg.82a8b9f27c59f2af1e1f99ef0b1cfee4.jpg

 

31_Plymouth2.thumb.jpg.eacb8befdb5d3e4862afe08542e15c69.jpg

  • Like 5
  • Thanks 2
Link to comment
Share on other sites

Here's another pic from today -- following George's Silver Arrow, with a wonderful Buick speedster in between.  (Okay, I was wrong when I said that my car was the only Buick at the event because I forgot about the "one-off" speedster made from a 1919 Buick chassis and engine.)

 

Plaidtour3.thumb.jpg.941b6ec02fcd2d25412cc8f2e03b7fef.jpg

  • Like 3
Link to comment
Share on other sites

22 minutes ago, Ben Bruce aka First Born said:

Sure is great when a repair does what it is meant to do.  Congratulations.  I understand the "anticipation" bit. I kept grimacing  when shifting into 3rd. But no grind!  And no bearing howl. Now have to listen to the FAN!

 

  Ben

 

Thank you, yes, it's great when things work out, isn't It?  So glad to hear that your repair worked out as well.

 

Neil

Edited by neil morse (see edit history)
Link to comment
Share on other sites

Thank you, Neil!  It was great to see you and your Buick again, and having a chance to admire the beautiful instrument cluster you worked so long and hard to achieve.

 

And it was a great relief for me, being ahead of you on downgrades, that your pop-out-of-3rd-gear issue has been successfully resolved!  🙂

  • Like 1
Link to comment
Share on other sites

  • 1 month later...

Oil Pan and Pump

 

With a shut in order in place, I was looking around for another project to take on so I decided to finally drop the oil pan on my car and take a look at the oil pump.  First, I had to seek advice on the technical forum because I couldn't figure out how to get to the front bolts on the pan.  I got immediate and welcome help, as I figured I would.

 

I followed Dave Stovall's step-by-step procedure, and got the pan off pretty easily.  The only difficulty was (as Dave warned me) the four bolts -- two on each side -- that are in between the front bolts and the remaining openly accessible ones.  These are hard to reach, but with a socket extension, a U-joint, and a lot of patience, I eventually got them out.  The only thing I would add to Dave's list is a tip I got from Don Micheletti.  I got two 2" bolts and put one on each side before I used a screwdriver and a hammer to finally pry the gasket loose.  This way the pan was caught by the two long bolts when it dropped.  Also, as indicated in the other thread, I actually had to remove the pump before I could wrestle the pan all the way out because the bottom of the pump was hanging up on the forward baffle in the pan.  Here's how it looked when I got the pan and pump out.

 

oil_pan.jpg.e273c19343e722301035f57a9b020300.jpg

 

oil_pump.jpg.ef0caa30df1ba98e8a79d2db8c819962.jpg

 

The pan has about 1/4" to 1/2" of sludge in the bottom, which I guess is pretty typical.  The pump looks fine, but the pick-up screen was pretty clogged up with the same kind of sludge.

 

oil_pump3.thumb.jpg.248ce22701461af32cbffe31a9ec858d.jpg

 

The plate at the bottom of the pump didn't look too bad, but I will go through the routine of sanding it smooth to see if it gives me a little more oil pressure.  (My car's pressure is okay, but not great.  It's about 45 lbs. on cold start, but goes down to 10 lbs. at idle when hot.  It maintains about 30 to 35 under load when warmed up.)

 

oil_pump2.thumb.jpg.2da94977f1cf23af68be1f1596a22450.jpg

 

So that's all for now.  I have the messy job of cleaning up the pan and then plan on giving it a new coat of Dante Red.  I also have to clean up the screen and then sand the plate and check the clearance with Plastigauge.  Standby for more reports.

 

 

 

 

  • Like 2
Link to comment
Share on other sites

One further photo: Here's what my crankshaft looks like.  The pistons look very new, which is good news.  (As I've said earlier in this thread, I don't have a good history on this car, and don't know what has been done to the engine -- although it runs very well.)

 

Crank.thumb.jpg.b8bcb58be18ff23046bf46e20c357c80.jpg

  • Like 1
Link to comment
Share on other sites

If it ain't broke, don't fix it! Please don't let anyone tell you to pull a main bearing cap or two and check the clearances, "just in case." Yes, maybe it's a good idea, but at the same time, it can lead you down a road of misery if things go sideways. Remember when someone told me to pull the bearing caps in my Limited rear end "just to have a look" and I dropped one and broke it? Yeah, don't let that be you. If it's running well, button it back up and go drive it!

 

Also remember to pack the oil pump with Vaseline before you put it back in so it can pull a prime when you fire it up.

Edited by Matt Harwood (see edit history)
  • Like 3
Link to comment
Share on other sites

Yes, thanks for that advice, Matt, although I had already come to the same conclusion.  Dealing with main bearings is way beyond my job description, at this point, and I agree that there is no indication that anything is wrong with them at present -- so that's the way I'm going to leave them!

Link to comment
Share on other sites

1 hour ago, neil morse said:

The plate at the bottom of the pump didn't look too bad, but I will go through the routine of sanding it smooth to see if it gives me a little more oil pressure.  (My car's pressure is okay, but not great.

 

If you sand it you run the risk of increasing the clearance between the plate and gears and losing more oil pressure.  The fix for a weak oil pump is usually to install a plate to take up the clearance caused by wear.  I do not know if a plate is made for your engine but suggest it probably is. 

  • Like 1
Link to comment
Share on other sites

2 hours ago, JohnD1956 said:

 

If you sand it you run the risk of increasing the clearance between the plate and gears and losing more oil pressure.  The fix for a weak oil pump is usually to install a plate to take up the clearance caused by wear.  I do not know if a plate is made for your engine but suggest it probably is. 

 

This is all new to me, of course, but I am just following the procedure that has been very frequently suggested on this forum as a fix for low oil pressure.  I'm also not understanding how sanding the plate could result in increasing the clearance.  As long as you make sure you're sanding it perfectly flat (by putting the sandpaper on a perfectly flat surface -- a piece of glass in my case), aren't you going to inevitably decrease the clearance?

Link to comment
Share on other sites

37 minutes ago, neil morse said:

 

This is all new to me, of course, but I am just following the procedure that has been very frequently suggested on this forum as a fix for low oil pressure.  I'm also not understanding how sanding the plate could result in increasing the clearance.  As long as you make sure you're sanding it perfectly flat (by putting the sandpaper on a perfectly flat surface -- a piece of glass in my case), aren't you going to inevitably decrease the clearance?

 

Think in terms of "sanding off" the old finish.  To get it flat you would be removing material from the high spots to get to the low spot.  The low spot however, is where there is already too much clearance. 

Link to comment
Share on other sites

I'm always ready to learn new things, but I'm afraid I really don't follow what you're saying.  In this situation, surely the low spots were only "low" in relation to the "high" spots.  They actually were indentations in the plate.  Once the plate is sanded perfectly smooth, they will no longer be low.  The whole plate will have a uniform clearance from the gears that is less than the previous "low" spots.  I don't think your "sanding off old finish" analogy makes sense in this context.  Anyhow, I don't want to argue with you -- we will just have to agree to disagree.

  • Like 1
Link to comment
Share on other sites

5 hours ago, old-tank said:

If that stuff on the pickup screen is hard carbon chunks you have either broken or severely worn piston rings.

 

The little chunks on the screen are not hard.  They crumble very easily in my fingers.  Also, my car does not smoke or burn oil, so I don't think it's got bad rings.

Edited by neil morse (see edit history)
  • Thanks 1
Link to comment
Share on other sites

2 hours ago, Ben Bruce aka First Born said:

Neil, I , too, am not sure what JD is thinking.  Your method is what I have always used.  Go for it! 

 

@neil morse And @Ben Bruce aka First Born.   I will defer to your experiences with engines of this vintage.  In the interest of discussion only, not arguing, my experience comes from the oil pumps on the Buick 350- 455.  These may be substantially different from yours.  At any rate,  in some cases these later V8's develop low oil pressure because the cavity of the oil pump gets scarred or gouged by the gears of the pump itself.  Since the oil pump requires a certain clearance between the gears and the cover, when a cavity gets scarred or gouged the clearance on one or both gears is increased, and the oil pressure goes down.  To fix that a plate is installed in the cavity with new gears and that returns the clearance to it's original spec.  I applied that theory to your engine.

 

In my application of that theory I thought that if there was scaring from one or both of your gears, and you sanded your plate flat, then to get it flat you would have to sand to the bottom of the deepest gouge.  By doing so I figured that would open up the gap between the gears and the top or bottom of the cavity and thus change your oil pressure to a lower value.  But I will acknowledge that I could be incorrect and thus my earlier post should be disregarded.

 

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

And now that i have thought about it more and looked at some rebuilding kits I realize that I was incorrect in my application of theory. Sanding the oil pump cover flat is right and the plate would be for the inside of the pump body where it would be much more difficult to get a flat surface. So with all these wasted digits I would say my earliest post on this topic is definitely incorrect.  My apologies. Moving on...

  • Like 1
  • Haha 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...