4104 misc information

[pd-drag]

Hello, I posted last week looking for some information on a 4104 and realized I did a poor job of listing what information I was looking for.   I have also identified some repairs/parts needed and would appreciate help in finding or sourcing parts.
1) What type of governor would a 1960 model governor come from the factory with.  Mine currently has a SWVS .  if this is not the one originally supplied would I see any difference between this one and what was originally supplied. 

2)  On initial start my oil pressure is ~35 psi at idle, it drops to <10 psi at idle when at operating temperature.  Is this normal.

3)  Looking for a repair kit for the pressure switch located in the compartment under the driver's seat.  I believe it is the for the low pressure indicating light switch.

4)  The bus settles on the left side both front and rear.  Would this be related to the pressure switch I did an preliminary snoop test (soapy water) and could find no leaks at the leveling valves or air bags. 

5) Looking for the handle and assembly that controls the main entry door.   

Thanks in advance for your help and comments.

[eagle19952]

2)  On initial start my oil pressure is ~35 psi at idle, it drops to <10 psi at idle when at operating temperature.  Is this normal.

What oil is in it now ? what is the ambient temps ? Operating temperature ?
Until you absolutely know the question is unanswerable.
What is the oil psi at road speeds ?

[siberyd]

PD Drag,

What part of the country are you in. I know a coiple of folks parting out 04's.

What is your coach's serial number?

You can send your response to my email address.

PD 4104 tracker
Siberyd

[gus]

4) Not related.

The left rear leveling valve controls both front and rear left side tilt so that valve is probably leaking or the connecting link is loose, probably the link. Push up on the link while there is air pressure and see if the bus levels. Be careful, there is very little clearance. Even better to do it with the wheels up on ramps. You can reach it if you have long arms.

When you repair the link you can use a slice of good rubber hose to replace the worn out grommets. Also use washers larger than the link hole for the grommet so the link at least stays in the hole when the rubber wears out.

If it isn't a loose link or failed valve then a bag is probably leaking, maybe into the steel air chamber above the bag, they are bad to corrode.

[pd-drag]

A couple of updates.  On the question related to oil pressure I was reading off the gauge located on the drivers dash the increments are targeted for 20 plus psi below 20 it transitions to a red/yellow band as opposed to incremental numbers.  Related to the left side sag issue I realized that there was place for a local oil pressure gauge on the oil inlet to the air compressor.  I installed a gauge there and can see while the front gauge reads in the red/yellow band once it gets warmed up the local gauge stays at 20 psi. 

The news gets worse for the air system.  After reviewing the air diagram in the maintenance manual and looking underneath the bus I discovered that the rear air beams have been removed from service.  I can see what appears to be an attempt at weld repair on the drivers outboard air beam. The leveling valves are still in service but not sure how much function I'm getting from them.  I can see that all four air bags have been replaced and based on the fact the fittings on the air beam are open I can only assume I have a solid top plate isolating the air bags from the beam. 

I'll have to start thinking about a test/repair plan. 

Thanks again for the input
 

[gus]

If it is plated, as it appears to be, the air beams are no longer involved.

Detach the leveling valve link and with air pressure, move it up and down slowly to see if it works. It is a delay system so give it time to act.

Do not get under anything!!

If it is a bad valve they are generic and can be found at most auto supply stores that sells heavy truck parts.

These engines don't have much oil press at idle but should have 40-60 psi at operating rpm.

[pd-drag]

I spent some time crawing around the Bus yesterday and did confirm a few things.  The first is the rear air beams have been removed the front are still in service.  The rear leveling valves have been replaced it appears the left rear is only working in one direction although I'm trying to trigger with a stick to keep from underneath.

I did replace the leaking pressure switch with a 21st century version.  Your right I did figure out alot of these parts are available through our local NAPA store which is our heavy truck supplier.  I also see were you were talking about checking the bushing on the leveling links currently all of mine are missing. 

On oil pressure i am running 40 psi plus at speed my gauge is a sending unit style which I guess is typical.  The problem is it's a 0-100 psi range which doesn't give alot of clarity in the lower PSI range.  .

Thanks again for your help
my main focus now is figuring out the governor

[gus]

You can't really move the valves without disconnecting the linkage. I was able to reach mine through the wheel well.

40 psi is a bit low at cruise speed, 50-60 is better.

Put the engine on fast idle then check the oil pressure gages at both ends. The front usually reads a bit lower than the rear.

The rear is mechanical and the front is electric so the very long wires to the front gage get more resistant with old age and give incorrect readings.

You can do it at idle but it works better at fast idle.

[pd-drag]

interestingly thats exactly what I did, I came to the same conclusion in that I was losing voltage and therefore pressure indication. 

my arms aren't long enough to reach through the wheel well, so i have to go through the exercise of blocking up the Bus  so I can access from underneath. 

[zubzub]

re oil pressure make sure you have the correct (single weight) oil in there.  Also re air system, my 04 had the rear reservoir bypassed because it was rusted out.  I aired up fast though.....aired down even faster when on the brakes a bunch.

[gus]

re oil pressure make sure you have the correct (single weight) oil in there.  Also re air system, my 04 had the rear reservoir bypassed because it was rusted out.  I aired up fast though.....aired down even faster when on the brakes a bunch.

Good point, so many make the mistake of using the 15-40 in stock most places now.

Mine rear tank was bypassed also but I found one on ebay and replaced it. Funny thing was I couldn't tell any difference!