Wednesday, November 18, 2009

Hot Springs Spa - I'm back in the saddle again!

Soon after my Labor Day party I decommissioned my inflatable Spa 2 Go hot tub in a fanfairless ceremony attended only by my dog and I. Actually the dog left half way through the events. However this was a blessing in disguise because it forced me to begin working on the abandoned hot tub that came with the house.

When we moved into the house, a none functioning hot tub made by Hot Springs Portable Spas sat in the yard. I am not sure about the "portable" part of the name, this thing is not going anywhere, easily. The only information we were given on its condition was that they thought it needed a new heater element. Opening up the access panel I found that the heater element housing was coated with a patch material that looked like plaster. With some help from my father in law, we poked around the electrical controls and concluded that everything was functional. I filled the tub and fired it up. The heater element was getting power and after several hours a noticeable increase in temperature was observed. However the heater element housing repair was not holding and was leaking. Thus the system was shut down and the tub drained so that additional sealant material could be applied to the housing. Once the system became water tight a tub of 102 degree water was produced. I was slightly troubled by this success, since the thermostat control was maxed out. I did not complain too much as I enjoy a beer in the tub after our first snow storm of the season. A weekend of hot tub soaking was all the spa would muster and soon the temperature dropped to 95 degrees.

Upon opening up the panel I was quickly able to identify the various components of the spa. I was greateful that the spa system was pretty simple. The experiance gained from the S2G was very handy.

1-Flow sensor

2-Jet pump

3-Heater

4-circulation pump

5-high limit sensor

6-temp control sensor

7-tub light

8-controller

Cracking the control box I was greeted with a slew of electronic components. Once again it was a relatively simple controller. Rather than have an all inclusive circuit board that does everything, this controller was old school; a bunch of relays, switches, potentiometer, and a few circuit boards made up the brains of the spa system.

1-sensor inputs

2-relays

3-thermostat controller

4-light switch

5-power in

6-power out to either circulation pump, heater or jet pump

7-power out to light

8-power out to either circulation pump, heater or jet pump

9-jet switch

10-jet on indicator light

My first inclination was to change out the heater element, since that is what the previous owners thought was wrong with the system. However based on some of the "johnny homeowner" repairs I found around the house, I was not so sure that PO thoughts were very reliable. At that time the voice of my old boss popped into my head. He use to say: do not use the "shot gun" approach to repairs. Shoot blindly and hope to hit something. Instead of just replacing parts and hoping that one of them solves the problem, you should figure out what is wrong with the system. I never thought the term "shotgun" approach was very appropriate, instead I think "machine gun" approach paints a more accurate image.
The first thing that I wanted to check was to make sure that the heater element was functioning properly. Messing with the temperature controller yielded clicks from the relay. A relay is a mechanical switch that turns power on and off. Signal voltage from a sensor is very low, and can not power the desired device, thus a relay is needed to handle the power demand of the device when a switched signal indicates it to do so. Tracing the wires back from the heater, I found the particular relay which powers it. This typical relay had six leads, or three pairs. In each pair a lead is for the positive terminal and one for the negative. One pair was for the signal voltage, one for power in and one for power out. I approached the system at a steady state with the thermostat set to max and temp of the tub at 95 degrees. I then took a volt meter and probed the leads. One set of leads showed 120 volts (the spa is a 120 volt system), and the other two showed nothing: the relay was off. Wiggling the temp setting switch around would result in a click. At this time two sets of leads showed 120 and one set show something like 12 volts: the relay was on. Setting the thermostat lower and allowing the system to reach steady state yield a 85 degree spa, turn the controller up would click on the relay. This meant that the heater was turning on and off and that most likely the heater could heat the tub past 95 degrees if the controller told it do so: the heater was good.
When my Spa 2 Go was not able to sustain temperature, the culprit was a failing temperature sensor. So I went to pull the two sensors. However this was a little more involved since I recently epoxied the sensors in place to stop the leaks. So now I had to remove the entire heater housing and bring it into the shop. Once inside I took a Dremel with a small cutter, and with the precision of a dentist went forth cut the the sensor free. With both sensor out I proceeded to test their resistances. Experience from the S2G told me that both sensors of a two sensor system do not fail at the same time and the same rate. The resistance of the sensors were the same at room temperature, a few hundredths of an ohm off, but that is nothing to worry about. Placing the sensors in a bucket of hot water yield an identical drop in resistance. The senors were most likely good. However I eventually found a graph of the sensors that plotted resistance vs. temperature. There was an off chance that the sensors were failing at the identical rate and was causing my problem. But based off the the graph my sensors appeared to be in great shape.
The next logical component that might be the source of my low resulting temperature was the thermostat controller. I however did not have a good test to identify if the current unit was functioning properly or not. All indications pointed that this was the culprit: consistent temperature (I was able to set it to a lower temp and have it stay at the lower temp), wiggling the switch would cause the relay to turn on. Though I was not 100% confident in my diagnosis, base on the process of elimination I was 90% sure. I found a replacement part on-line and speaking with the very helpful tech support, made me feel even better that the part in question was bad. All said and done a new thermostat controller was in the mail and my bank account was $80 leaner. I was taking a risk by not confirming the part was bad, since electronic parts are non refundable, however a house call from a spa repair person would typically incur a $200 bill for the first hour without the cost of parts. A few weeks had also elapsed and the need for the hot tub to be functional was beginning to become dire.
A few days later the part came. I finished epoxying the heater housing and reinstalled all the various components. In a day and a halve's time the tub was filled with 108 degree water.
Bang bang, mission accomplished.
I felt quite a sense of accomplishment and the punch line for old joke about the enigneer and the chalk came to to my mind. One dollar for the chalk, $499 to know where to put the "X".
Now to get the tub up onto my deck.

Monday, November 16, 2009

Moto Jack - a trail side work stand

Changing the tires of a motorcycle first requires the removal of the wheels. If your bike is equipped with a center stand this make the task a bit easier. If your bike did not come equipped with a center stand adding one could be difficult. I have always been told that a proper sized milk crate or a five gallon bucket is suitable to use as a work stand. I removed my wheels with the aide of a bucket. However what is one to do if you are out on the trail and suffer a flat. How would you support the bike while removing the wheels to change a flat. Five gallon buckets are difficult to ride with. Though I have seen many pictures of bikes propped up on log and rocks, there is a better option.



One clever member of ADVrider.com came up with a bucket substitute. When setting the bike onto a bucket one usually leans the bike onto its kickstand so that one of the wheels is off the ground, then inserts the bucket to rest upon. The side stand simply replaces the bucket and suspends one of the wheel off the ground. Which wheel off the ground is determined by the placement location of the the stand. Towards the back of the chassis or swing arm and the rear wheel is off the ground, toward the front and the front wheel lifts.




The addition of a strap depressing the front brake adds to the stability of the bike when the rear wheel is elevated. When the front wheel is in the air simple leave the bike in gear to lock the rear wheel.

The prototype stand was made of steel but now they are all made of Aluminum. So light and easy to store. At home however I will still use a real moto stand. Hopefully I will never have to use this product for its intended purpose, but for $20 and a pound or two of weight it is well worth owning.

http://www.advrider.com/forums/showthread.php?t=380877&highlight=stand

Friday, November 13, 2009

Road Trek - Lifting a 94 Dodge Van

A friend of mine recently purchased a Road Trek Class B motor home. It is built on a 1994 2wd one ton Dodge Van chassis. The coolest thing about this little camper is just that: it is little. It is the size of a full size van, yet it is completely self contained: hot water, shower, toilet, stove, furnace and fridge. Cool as it was he complained that it would bottom out on the smallest of bumps. What condition are your shocks in?: new. I was doubtful that it was actually "bottoming out". Worn out suspension components, such as ball joints will often cause a clunk which could feel like the suspension hitting the limits of its travel. However upon a visit to his place reviled that in fact his suspension could be BO.


The suspension appeared to have sagged, though the tell tale negative camber of lowered cars or those with sagging springs was not present. However the lower bumper stop (B) was less then 3/4 of an inch from resting on it's stop. Comparing the the available travel for compression (C) verses the allowable for rebound (R), shows that at the vans current ride height an estimated 25/75 ratio of compression/rebound existed (that is being generous, in fact it seems like it was closer to 10/90). 50/50 is more typical with some more aggressive sets ups at 75/25. In the picture to the right you can see both the rebound (UB) and compression bump stops. Notice the deformation of the lower bump stop from repeated bottoming out.

This last time my friend came to visit he drove his Road Trek out. Naturally I wanted to help him fix his BO issue. I figured a new set of OEM springs were the best solution. I wanted to install some lift springs to gain him some extra lift but was afraid that such a modification could lead to fitment problems, misalignment, or a harsh ride. Better leave it stock for this weekend job on someone else's rig.

I had spent some time looking for a reference on the spring replacement. None were found. I guess Dodge van owners just drive around sagging.
The front suspension is a double arm coil spring over shock set up. The coil spring sits in a bucket within the front cross member/frame. The lower control arm holds the lower half of the spring in place. The shock runs though the middle of the spring, attached to the frame on one end and through a pin bolted to the lower control arm on the other. Though the the shock run through the middle of the coil spring, these were not consider "coil overs" because they were not attached together, each attaches to the frame and the suspension via its own mounting location. The lower arm is a single pivot modified channel, with a compression rod.


My original intention was to disconnect the lower ball joint from the knuckle and drop the lower control arm. This was more difficult to do then I imagined. The lower ball joint sat tightly in its tapered fit and did not want to separate. I could not get a separator tool in there due to the tight fit. Though I started hammering a pickle fork into the cavity I soon stopped cause I did not want to ruin his ball joint or BJ boot. Instead I removed the upper control arm mounts. The UCA is a dual pivoting "A" on a cross pin. The pin is attached by two bolts to a brackets on the frame. Once removed I "flipped" the entire assembly down and freed the LCA, which still had the knuckle, brakes, and UCA attached to it. Once the LCA was free we were able to pull out the coil spring. The UCA cross pin bolts to slotted holes in the bracket, the positioning of the pin is responsible for camber and caster adjustments. Be sure to mark the location of the cross pin in relation to the frame/brackets prior to removal.

Comparing the new spring with the old springs was not very satisfying. They were the same height. I just hope that the break down of the spring was caused by metal fatigue and was not visible. The new coil was not exactly the same as the older one either. The windings of the coil were tighter.
The first side took us 3 hours to do. The second side 20 minutes. After we tightened the last bolt and lowered it to the ground I took an "afterwards" measurement. The van sat almost three inches higher. After settling, I figure we would have gained two inches of height. Test drives proved that the spring replacement was a success and the van no longer bottomed out!
Below is a step by step procedure for spring replacement:
-Jack up vehicle
-Set on jack stand
-remove wheels and set underneath the frame
-Mark upper control arm cross pin location
-remove two brake line brackets
-remove shock lower mount (two bolts on a small cross pin)
-remove bracket holding the lower bump stop, compression rod, and sway bar
-unbolt upper controller arm cross pin
-unbolt shock upper mount nut
-remove coil spring
Installation is the reverse of removal (ha ha, I hate it when I read this in repair manuals, but it basically is). The most difficult part is to reattach the UCA. The bolt and large nut on the cross pin in particular. You can reach behind and lift the nut in place, or attempt to shim the nut into position and fish for threads with a too short of bolt. A second set of eyes looking through the open hood is needed to align the cross pin back in position.
And there you have it one Dodge 1 Ton Van lifted two inches!!

Thursday, November 12, 2009

Hitchhikers Guide To Tahoe

Hitchhiking is one of those big No No's your mother warned you about. It is akin to eating Halloween candy with an open wrapper. Like Communism the idea is good, but a few bad apples spoils the whole damn bunch. I have to admit I have hitchhiked a few times in my life. The situation were usually rather dire, and the risk in hitchhiking were outweighed by the benefits. In ski resort towns however hitchhiking is much more accepted as a form of reliable transportation. I regularly give hitcher a lift as does the local population.

So why is it now ok to do so in this situation. My primary reason is pity. Ski resorts employ alot of foreigners to work for the seasons on a J-1 work visa. These J-1s are usually upper middle class colledge kids from South American countries (Brazil). Without cars they have to rely on public transportation, which if any of you have used... I'll stop there cause I doubt most that read this have never ridden a bus other than a school bus from your earlier years. So if I see someone standing on the side of t \he road wearing a ski resort jacket and I am heading in that direction, I will usually stop and pick them up. I do not pick up smelly homeless dudes, however ever skiers and boarders are a group of people that I will give rides to.

Seeing hitchhikers often, I can say that some of them do not know how to properly hitch, thus I wanted to write a few guidelines to make it easier and safer to do so.

For the Hitchhiker

-the most important thing is to stand in a spot that a potential ride giver can pull off the road. Do not stand on the side of the a busy highway with no shoulder, or simple walk with your thumb out.

-Know where you are going, and a good location that to be dropped off. Do not make your driver turn off the main road or deviate his course to make the drop off. Drop off locations should be always on the side of the street they are already traveling.

-If hitching at night stand under a street light.

-If the driver can not take you to your final destination, consider waiting for the next driver, or know of a good intermediate location where you might be able to pick up your next ride. Don't be dropped off in the middle of nowhere.

-Be safe. Try hitching in pairs, and it is ok to refuse rides from shady looking drivers in windowless vans.

-As a rider your job is to engage in lively conversation if the driver wishes to do so.


For the Drivers

- No need to go out of your way to give someone a ride. Be it a lack of space in your car, or if you know that you are not going to at least the next major point along the route.

-Do not stop in a dangerous location. Be sure that you are able to pull completely off the roadways when picking someone up.

-First thing to do when approaching a potential rider is to ask where they are going, and is it possible to give them a ride. If not simply move on. There will be someone else.

-Do not expect the rider to pay for gas.

-Be safe. A single woman should not pick up a group of scruffy looking guys!

Both hitchhiking and giving hitchers ride can be DANGEROUS. I can recall several true hitchhiking horror events that have made our local news. I am not trying to influence you to partake in this form of transportation. These are just some guideline if you already do so.

Tuesday, November 3, 2009

Mattracks - Snow tires no more

Winter is almost here. And like most who live in snow country, it is time to unearth the winter/snow tires, and transform our cars for the season. This year however I was think that I might do something different. I really want more snow performance. Thoughts?



The only company that I could find which manufatured these tracks is Matttracks.

http://www.mattracks.com/index.htm

I could not locate a company called "Trax"