46RH (A518) Conversion project

[Rickf1985]

And rushing to get it done for your trip. I can tell you about a couple good screwups due to that. Ever forget to tighten the lug nuts on a trailer wheel? Bad things happen. W% W%

[Sasquatch]

Too many nights working on it until midnight after a full day of work I guess.  I am not a young buck any more.  When I question if I am alive enough to drive, I shouldn't have been building a transmission.  D:oH!

[Froggy1936]

Opps,  Were the burned plates still flat ? or were they concaved  ? Got any pics ?  Frank

[Sasquatch]

Going back together.



The carnage.  Did not check flatness.  I doubt they were flat.

[Rickf1985]

So what did they think of your modified transmission? And how did the front pump bushing look?

[Sasquatch]

Not only were they impressed by the modified transmission, the coach as a whole has become quite popular.  Even other customers are asking to see the inside and talk to me about it.  They are astounded that it is 42 years old.  The other mechanics even come over and sneak in and give my girls love when I am off doing other things.





But they were really impressed with how the modified bellhousing worked.  They also blew off my disgrace for my failure in the transmission and said that it was really easy to make the mistake I did and that even pros do it on occasion.


Rick, the front pump busing showed no wear.  Everything is great.

[Rickf1985]

So there you go, alignment spot on, probably better than original and I figured those guys would be all over it. Yea, as a mechanic I never liked people hanging over me giving their "opinion" of what was wrong and how to fix it, since their "opinion" was 99% of the time miles off from correct or what was needed. But if they were a true mechanic there is a big difference, first off they usually sit off to the side and say nothing until asked or they offer up very concise descriptions of the problems they were having, and then they leave it to me to diagnose. At that point I know I am dealing with a real mechanic and I will usually involve them in the repair.

[Sasquatch]

I'm home, but the adventure is not quite over.  During the test drive Friday evening, we had no OD with the switch.  They swapped the OD solenoid with one out of a core transmission they had laying around and OD came back to life.  I left Saturday morning early and was happy as a clam until I left north out of Mesquite, NV heading for Salt lake.  After 30 or so miles pulling steep grades in 3rd it flattened out and I hit the OD switch, nothing happened.  The transmission felt great, just no OD.  Temps were cool, shifts nice and firm, good down shifts, etc.


I spent the night at a Walmart in Provo and I went through the wiring to the OD unit and everything still checked out ok.  I drove home Sunday, and quite frankly, the head winds were unbelievable.  I would have been in 3rd all day anyway.  I do not think anything is wrong with the core of the transmission.  It feels fantastic.  I think the issue lies in the solenoid/valve body or OD piston, all of which can be serviced without pulling the transmission, again. 


I am going to hook up my pressure test equipment and take it for a drive with the gauge plugged into the OD port and see what it does.  This will give me a good idea where the problem lies.  And another point, I am going to get really techie here, but there may be another cause.  I noticed a few electrical glitches with the coach while driving home, and at the same time the 440 was not running as smooth as it should.  This evening I checked some things out while it was idling roughly.  I grabbed a spray bottle with water in it and started spraying the distributor and spark plug wires and you should have seen the light show.  Cap was arcing through as well as all the wires.  The electrical noise in that engine compartment must have been intense.  The power wires to the solenoid ran right by the spark plug wires.  It is very possible that this level of intense noise, or a few stray electrical spikes could very well have damaged that solenoid or interfered with it's operation.  Sounds like a long shot, but not really out of the realm of realistic possibility.


I wanted to be able to really see a fuel mileage increase, but with the transmission failure, plus the seriously intense head winds both going and returning, and now with the bad ignition system, I am surprised I got the mileage I got. I averaged 7 mpg both going and coming for the entire trip.  Exactly what I got last year with no winds or problems.


The times I did have the OD functional, it was great.  While I hang my head in failure over no real fuel mileage increase, the added comfort it adds of being able to drive 70 in a much more relaxed manner is worth it.


So, I am still working on it, but she is getting close.  I have new ignition wires and components on the way, when they get in I will take it for another drive and see what the pressures are like of if the electrical noise affected the operation.  I'll keep you all posted.

[Rickf1985]

I seriously doubt that you would have enough inductive current to cause damage and generally that kind of noise does not affect mechanical solenoids. It is high voltage but low current. It will definitely affect your fuel injection system though! And it will affect the fuel mileage on the injection system. Are you still in touch with the Trans-go people?

[Froggy1936]

Very good to be back home where you can Diagnose one thing at a time with less pressure Good Luck  Frank

[Shawn62]

Glad to hear you made it home to your own shop.  Hope the OD problem is a simple fix.  I had a wiring problem with a solenoid once.  I checked the wires for continuity and voltage drop and they were ok.  I was about ready to order a new solenoid. I then remembered to check the resistance.  Turned out a wire was badly corroded inside the insulation.  Resistance was way high. PO had a habit of poking holes in wires with test light probe. I rewired it and was good to go.  Good luck.

[Sasquatch]

Rick, you are probably right, but I want to dot every I and cross every T so that I can narrow in on the real cause.  I am not going to drive it again until my new parts come in.


Shawn,  I also checked resistance as well as continuity through the wires and solenoid.  All is good.  In fact, the Solenoid even checks good as far as resistance, so in theory, it should work.  But theory is not always correct.  The ball could be stuck, debris in it (doubtful with how clean they got everything), or some other issue. 


I am betting, quite frankly, that when I burnt the transmission to the ground on my first attempt that somehow I warped the valve body so that the OD selector valve does not slide properly in the bore once pressures get up to running pressures.  If that valve is hanging up or dragging, it would cause the multiple things I have experienced with the OD since I got on the road.  So, that is where I am placing my money.  I did order a new solenoid, and will install it in any case, but I bet I will have to pull the valve body one last time and focus on that valve.


Teaching my youngest daughter how to drive the RV....





My traveling companions

[Froggy1936]

Don't you have a spare valve body ? Frank

[Sasquatch]

Frank, no, i dont.  I had a core 727, but that does not help me.

[Sasquatch]

Just swapped my spark plug wires, cap and rotor.... can I have a re-do on my vacation?  Old wires ohmed out at between 11K and 16k ohms with two of them dead.  New ones all between 700-900 ohms....  She runs so smooth now...

Next, transmission pressure test.

[Sasquatch]

Just got back from a drive.  In 3rd, zero pressure on OD piston.  Throw the switch and I get 10 psi to the OD piston.  Switch off, it goes back to zero.


So it seems like the solenoid is working, but I am not getting pressure build up in the OD piston.  Time to pull the valve body and figure out what is seized up.

[Rickf1985]

Before you do that you ought to call the Trans-Go guys and see what they suggest. They may want you to test a couple other things first.

[Sasquatch]

On my list for Monday morning Rick.  I am also going to check main line pressure.  Since 1-3 feel fantastic, I do not anticipate any pump issues, but I am going to do it any way just to put a check on that question.


I am betting that I have a shift valve hanging up in the bore.  We will see if I am right.


I still feel that nothing is wrong with the core of the transmission.  There is a ghost somewhere in the valve body that I need to find.

[Sasquatch]

Spoke with Transgo and he gave me my marching orders for the tear down.  First, pull the valve body but leave it intact.  Pressure check the OD piston from the VB port.  If that is ok, back pressure test the VB's OD circuit from the OD port backwards looking for leaks.  If that is all good, pull the VB down and look for stuck pistons.

[Rickf1985]

You are going to have to make up some round adapters to plug into square holes for those pressure tests. A buddy of mine had a whole pegboard covered with homemade adapters that would bolt to the trans and seal up all the ports and provide test fittings for all of those test. He had them for every transmission ever made. He probably still has them but they would be in boxes somewhere. He just does rebuilds in his garage anymore. You take it there and you pick it up.

[Sasquatch]

Well, nothing is needed.  It was quickly seen what the problem is as far as OD pressure.  Hunks of the lip seal for the OD piston were in the bottom of the pan.  Also a good slime of clutch material from the OD clutch.

I called Kermit who's shop built it and discussed it with him.  He told me that for some reason the VB was not dumping the pressure when the switch was turned off leaving the OD clutches trying to hang on.  He said that he can gaurantee the OD clutch plates are smoked again and when they smoked the OD piston over extended allowing the lip seal to flip out and tear into pieces.

He is building me a completely new VB assembly and will be shipping it to me.  He told me to go ahead and pull the OD section and replace the frictions and steels (at his cost).

I pulled the VB and found a couple of the OD pistons hanging up in the bore.  This may have been the ultimate cause of the pressure build up.  Hopefully the new VB will take care of the issues.

[Rickf1985]

Kermit is one hell of a guy!!!! He needs special mention on here in case anyone else has issues anywhere in that area.

[Sasquatch]

I agree.  If you are ever in or around Kingman Arizona and need any auto work, I highly recommend Kermit's transmission.  They are a full service shop.  Do not judge them by their looks, it is kind of a cluttered, dumpy shop, but Kermit is a stand up guy who takes care of his customers.

Kermit's Certified Transmissions
2425 Northern Ave.
Kingman, AZ 86409
928-757-1020

[Sasquatch]

Bloody 'ell, I think I found the smoking gun.


Upon first glance, other than seeing the carnage to the OD clutch, I could see nothing wrong in the OD unit.  But something has never sat right with me.  How can the OD clutch have drag on it but the OD direct clutch still be engaged?  They are both operated at the same time by the same piston.  As the piston moves, it disengages the OD direct clutch and engages the OD clutch right after.


So, back to the manuals, parts diagrams, and engineering papers on this system...  There are multiple configurations for clutch stack ups depending on the application.  Everything from a 2 friction OD clutch in a Jeep, to a 5 friction setup in the diesel, which I have.  Somehow, I made the mistake of putting the correct number of frictions in there but also installed a thick pressure plat on the outside of the pack where the application called for just a steel to act as the pressure plate.  Ding, we have a winner.  My clutch pack was too thick and dragging at all times.


The shop in AZ, just followed suit because the exploded diagrams showed a pressure plate in the diagrams.  You had to go deep in the paperwork to find where it specified diesel applications as having no pressure plate which would make it .25 thinner clutch pack.  So, this answers my concerns.  I think I am going to have it nailed this time.

[Rickf1985]

So now what are you going to tell Kermit and do with the valve body he is sending you?